U.S. patent application number 11/927680 was filed with the patent office on 2008-05-08 for electrochemically fabricated hermetically sealed microstructures and methods of and apparatus for producing such structures.
This patent application is currently assigned to Microfabrica Inc.. Invention is credited to Vacit Arat, Christopher A. Bang, Adam L. Cohen, John C. Dixon, Michael S. Lockard, Dennis R. Smalley.
Application Number | 20080105558 11/927680 |
Document ID | / |
Family ID | 46325502 |
Filed Date | 2008-05-08 |
United States Patent
Application |
20080105558 |
Kind Code |
A1 |
Cohen; Adam L. ; et
al. |
May 8, 2008 |
Electrochemically Fabricated Hermetically Sealed Microstructures
and Methods of and Apparatus for Producing Such Structures
Abstract
In some embodiments, multilayer structures are electrochemically
fabricated from at least one structural material (e.g. nickel), at
least one sacrificial material (e.g. copper), and at least one
sealing material (e.g. solder). In some embodiments, the layered
structure is made to have a desired configuration which is at least
partially and immediately surrounded by sacrificial material which
is in turn surrounded almost entirely by structural material. The
surrounding structural material includes openings in the surface
through which etchant can attack and remove trapped sacrificial
material found within. Sealing material is located near the
openings. After removal of the sacrificial material, the box is
evacuated or filled with a desired gas or liquid. Thereafter, the
sealing material is made to flow, seal the openings, and
resolidify. In other embodiments, a post-layer formation lid or
other enclosure completing structure is added.
Inventors: |
Cohen; Adam L.; (Van Nuys,
CA) ; Lockard; Michael S.; (Lake Elizabeth, CA)
; Smalley; Dennis R.; (Newhall, CA) ; Arat;
Vacit; (La Canada Flintridge, CA) ; Bang; Christopher
A.; (San Diego, CA) ; Dixon; John C.; (Van
Nuys, CA) |
Correspondence
Address: |
MICROFABRICA INC.;ATT: DENNIS R. SMALLEY
7911 HASKELL AVENUE
VAN NUYS
CA
91406
US
|
Assignee: |
Microfabrica Inc.
|
Family ID: |
46325502 |
Appl. No.: |
11/927680 |
Filed: |
October 30, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11435809 |
May 16, 2006 |
|
|
|
11927680 |
Oct 30, 2007 |
|
|
|
10434103 |
May 7, 2003 |
7160429 |
|
|
11435809 |
May 16, 2006 |
|
|
|
60379182 |
May 7, 2002 |
|
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60430809 |
Dec 3, 2002 |
|
|
|
60681788 |
May 16, 2005 |
|
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Current U.S.
Class: |
205/170 |
Current CPC
Class: |
B81C 1/00293 20130101;
H01P 3/06 20130101; H01P 5/183 20130101; H01P 11/005 20130101; H05K
3/4647 20130101; B81C 2201/0197 20130101; G01P 15/0802 20130101;
B81C 1/00333 20130101; H01P 11/00 20130101; H01P 1/202 20130101;
B81C 2203/0145 20130101; B81B 2201/042 20130101; G01P 15/125
20130101; C25D 1/003 20130101 |
Class at
Publication: |
205/170 |
International
Class: |
C25D 5/10 20060101
C25D005/10 |
Claims
1. An electrochemical fabrication process for producing a
three-dimensional structure from a plurality of adhered layers, the
process comprising: (A) depositing at least a portion of a layer
onto the substrate, wherein the substrate may comprise previously
deposited material; and (B) forming a plurality of layers such that
each successive layer is formed adjacent to and adhered to a
previously deposited layer; wherein the layers comprise at least
three different materials and wherein the layers contain patterns
of material comprising: (1) a desired structural component that is
to be protected and that is formed from at least one structural
material; (2) a protective enclosure that is formed at least in
part from a structural material, wherein at least one portion of
the enclosure at least partially surrounds the desired structural
component, and wherein the enclosure is limited by at least one
opening therein; (3) a sealing material located near the at least
one opening; and (4) a sacrificial material located at least
partially between the desired structural component to be protected
and at least a portion of the enclosure; wherein after formation of
the layers at least portion of the sacrificial material located
between the desired structural component and at least a portion of
the enclosure is removed; and wherein after the removal of the
sacrificial material, the sealing material is made to temporarily
flow and seal at least one opening to block or significantly limit
a passage of material from an outside of the enclosure to an inside
of the enclosure via the at least one sealed opening, and wherein
the enclosure includes an electrical feed through;
2. The process of claim 1 wherein the enclosure includes a lid that
includes the electrical feed through.
3. The process of claim 2 wherein an electrical connection is made
from the electrical feed through to at least a portion of the
desired structural component.
4. The process of claim 3 wherein the electrical connection
includes a compliant element for making a pressure connection.
5. The process of claim 1 wherein the enclosure includes a portion
that has a thickness no greater than a thickness of a single layer
from which the enclosure is formed and wherein the portion is
formed from at least two deposited layers of material.
6. The process of claim 5 wherein a planarization operation is used
in forming each of at least two of the deposited layers that form
the portion.
7. The process of claim 1 wherein the removal of the sacrificial
material comprises etching.
8. The process of claim 1 wherein after removal and prior to
sealing, a reducing agent is provided at least one location within
or near the at least one opening to reduce the presence of any
oxides at the at least one location.
9. The process of claim 1 wherein after removal and prior to
sealing, a desired fill gas is made to fill an interior cavity of
the enclosure in which the desired structural component is at least
partially located.
10. The process of claim 1 wherein after removal and prior to
sealing, an interior cavity of the enclosure in which the desired
structural component is at least partially located is at least
partially evacuated.
11. The process of claim 1 wherein at least one opening and the
sealing material are so located that the sealing material need not
flow over any structural material when flowing to seal the
opening.
12. The process of claim 1 wherein at least one opening is sealed
at least in part by the surface tension of the flowable sealing
material causing the sealing material to bulge and bridge the
opening.
13. The process of claim 1 wherein at least one opening has sloped
walls that give the opening a non-fixed cross-sectional dimension
through the enclosure, the sealing material, or a combination of
the sealing material and the enclosure.
14. The process of claim 1 wherein at least one opening has a
restriction around which sealing material will flow when sealing
the opening.
15. An electrochemical fabrication process for producing a
three-dimensional structure from a plurality of adhered layers, the
process comprising: (A) depositing at least a portion of a layer
onto a substrate, wherein the substrate may comprise previously
deposited material; and (B) forming a plurality of layers such that
each successive layer is formed adjacent to and adhered to a
previously deposited layer wherein the layers comprise at least two
different materials and wherein the layers contain patterns of
material comprising: (1) a desired structural component that is to
be protected and that is formed from at least one structural
material; (2) a protective enclosure that is formed at least in
part from a structural material, wherein at least one portion of
the enclosure at least partially surrounds the desired structural
component, and wherein the enclosure is limited by at least one
opening therein; (3) a sacrificial material located at least
partially between the desired structural component to be protected
and at least a portion of the enclosure; wherein after formation of
the layers at least portion of the sacrificial material located
between the desired structural component and at least a portion of
the enclosure is removed, wherein after the removal of the
sacrificial material, a seal is formed between the protective
enclosure and a sealing structure wherein at least one of the
protective enclosure or sealing structure comprises a sealing
material that may be used in establishing a sealing of the at least
one opening to block or significantly limit a passage of material
from an outside of the enclosure to an inside of the enclosure via
the at least one sealed opening, and wherein the enclosure includes
an electrical feed through.
16. The process of claim 15 wherein the enclosure includes a lid
that includes the electrical feed through.
17. The process of claim 16 wherein an electrical connection is
made from the electrical feed through to at least a portion of the
desired structural component.
18. The process of claim 17 wherein the electrical connection
includes a compliant element for making a pressure connection.
19. The process of claim 15 wherein the enclosure includes a
portion that has a thickness no greater than a thickness of a
single layer from which the enclosure is formed and wherein the
portion is formed from at least two deposited layers of
material.
20. The process of claim 19 wherein a planarization operation is
used in forming each of at least two of the deposited layers that
form the portion.
Description
RELATED APPLICATIONS
[0001] This application claims benefit of 60/681,788, filed May 16,
2005 and is a continuation of U.S. patent application Ser. No.
11/435,809 which is a continuation in part of U.S. patent
application Ser. No. 10/434,103, filed on May 7, 2003 which in turn
claims benefit of U.S. Provisional Patent Application Nos.
60/379,182, filed on May 7, 2002, and 60/430,809, filed Dec. 2,
2002. Each of the above noted priority applications is hereby
incorporated herein by reference as if set forth in full.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of
electrochemical fabrication and the associated formation of
three-dimensional structures via a layer-by-layer build up of
deposited materials. In particular, it relates to the formation of
microstructures and the concurrent formation of packaging for such
structures, such that for example, sacrificial material(s) are
removed from internal cavities of the package and critical portions
of the structure are sealed within the cavities.
BACKGROUND OF THE INVENTION
[0003] A technique for forming three-dimensional structures (e.g.
parts, components, devices, and the like) from a plurality of
adhered layers was invented by Adam L. Cohen and is known as
Electrochemical Fabrication. It is being commercially pursued by
Microfabrica Inc. (formerly MEMGen.RTM. Corporation) of Burbank,
Calif. under the name EFAB.TM.. This technique was described in
U.S. Pat. No. 6,027,630, issued on Feb. 22, 2000. This
electrochemical deposition technique allows the selective
deposition of a material using a unique masking technique that
involves the use of a mask that includes patterned conformable
material on a support structure that is independent of the
substrate onto which plating will occur. When desiring to perform
an electrodeposition using the mask, the conformable portion of the
mask is brought into contact with a substrate while in the presence
of a plating solution such that the contact of the conformable
portion of the mask to the substrate inhibits deposition at
selected locations. For convenience, these masks might be
generically called conformable contact masks; the masking technique
may be generically called a conformable contact mask plating
process. More specifically, in the terminology of Microfabrica Inc.
(formerly MEMGen.RTM. Corporation) of Burbank, Calif. such masks
have come to be known as INSTANT MASKS.TM. and the process known as
INSTANT MASKING.TM. or INSTANT MASK.TM. plating. Selective
depositions using conformable contact mask plating may be used to
form single layers of material or may be used to form multi-layer
structures. The teachings of the '630 patent are hereby
incorporated herein by reference as if set forth in full herein.
Since the filing of the patent application that led to the above
noted patent, various papers about conformable contact mask plating
(i.e. INSTANT MASKING) and electrochemical fabrication have been
published: [0004] (1) A. Cohen, G. Zhang, F. Tseng, F. Mansfeld, U.
Frodis and P. Will, "EFAB: Batch production of functional,
fully-dense metal parts with micro-scale features", Proc. 9th Solid
Freeform Fabrication, The University of Texas at Austin, p 161,
August 1998. [0005] (2) A. Cohen, G. Zhang, F. Tseng, F. Mansfeld,
U. Frodis and P. Will, "EFAB: Rapid, Low-Cost Desktop
Micromachining of High Aspect Ratio True 3-D MEMS", Proc. 12th IEEE
Micro Electro Mechanical Systems Workshop, IEEE, p 244, January
1999. [0006] (3) A. Cohen, "3-D Micromachining by Electrochemical
Fabrication", Micromachine Devices, March 1999. [0007] (4) G.
Zhang, A. Cohen, U. Frodis, F. Tseng, F. Mansfeld, and P. Will,
"EFAB: Rapid Desktop Manufacturing of True 3-D Microstructures",
Proc. 2nd International Conference on Integrated
MicroNanotechnology for Space Applications, The Aerospace Co.,
April 1999. [0008] (5) F. Tseng, U. Frodis, G. Zhang, A. Cohen, F.
Mansfeld, and P. Will, "EFAB: High Aspect Ratio, Arbitrary 3-D
Metal Microstructures using a Low-Cost Automated Batch Process",
3rd International Workshop on High Aspect Ratio MicroStructure
Technology (HARMST'99), June 1999. [0009] (6) A. Cohen, U. Frodis,
F. Tseng, G. Zhang, F. Mansfeld, and P. Will, "EFAB: Low-Cost,
Automated Electrochemical Batch Fabrication of Arbitrary 3-D
Microstructures", Micromachining and Microfabrication Process
Technology, SPIE 1999 Symposium on Micromachining and
Microfabrication, September 1999. [0010] (7) F. Tseng, G. Zhang, U.
Frodis, A. Cohen, F. Mansfeld, and P. Will, "EFAB: High Aspect
Ratio, Arbitrary 3-D Metal Microstructures using a Low-Cost
Automated Batch Process", MEMS Symposium, ASME 1999 International
Mechanical Engineering Congress and Exposition, November, 1999.
[0011] (8) A. Cohen, "Electrochemical Fabrication (EFAB.TM.)",
Chapter 19 of The MEMS Handbook, edited by Mohamed Gad-EI-Hak, CRC
Press, 2002. [0012] (9) Microfabrication--Rapid Prototyping's
Killer Application", pages 1-5 of the Rapid Prototyping Report,
CAD/CAM Publishing, Inc., June 1999.
[0013] The disclosures of these nine publications are hereby
incorporated herein by reference as if set forth in full
herein.
[0014] The electrochemical deposition process may be carried out in
a number of different ways as set forth in the above patent and
publications. In one form, this process involves the execution of
three separate operations during the formation of each layer of the
structure that is to be formed: [0015] 1. Selectively depositing at
least one material by electrodeposition upon one or more desired
regions of a substrate. [0016] 2. Then, blanket depositing at least
one additional material by electrodeposition so that the additional
deposit covers both the regions that were previously selectively
deposited onto, and the regions of the substrate that did not
receive any previously applied selective depositions. [0017] 3.
Finally, planarizing the materials deposited during the first and
second operations to produce a smoothed surface of a first layer of
desired thickness having at least one region containing the at
least one material and at least one region containing at least the
one additional material.
[0018] After formation of the first layer, one or more additional
layers may be formed adjacent to the immediately preceding layer
and adhered to the smoothed surface of that preceding layer. These
additional layers are formed by repeating the first through third
operations one or more times wherein the formation of each
subsequent layer treats the previously formed layers and the
initial substrate as a new and thickening substrate.
[0019] Once the formation of all layers has been completed, at
least a portion of at least one of the materials deposited is
generally removed by an etching process to expose or release the
three-dimensional structure that was intended to be formed.
[0020] The preferred method of performing the selective
electrodeposition involved in the first operation is by conformable
contact mask plating. In this type of plating, one or more
conformable contact (CC) masks are first formed. The CC masks
include a support structure onto which a patterned conformable
dielectric material is adhered or formed. The conformable material
for each mask is shaped in accordance with a particular
cross-section of material to be plated. At least one CC mask is
needed for each unique cross-sectional pattern that is to be
plated.
[0021] The support for a CC mask is typically a plate-like
structure formed of a metal that is to be selectively electroplated
and from which material to be plated will be dissolved. In this
typical approach, the support will act as an anode in an
electroplating process. In an alternative approach, the support may
instead be a porous or otherwise perforated material through which
deposition material will pass during an electroplating operation on
its way from a distal anode to a deposition surface. In either
approach, it is possible for CC masks to share a common support,
i.e. the patterns of conformable dielectric material for plating
multiple layers of material may be located in different areas of a
single support structure. When a single support structure contains
multiple plating patterns, the entire structure is referred to as
the CC mask while the individual plating masks may be referred to
as "submasks". In the present application such a distinction will
be made only when relevant to a specific point being made.
[0022] In preparation for performing the selective deposition of
the first operation, the conformable portion of the CC mask is
placed in registration with and pressed against a selected portion
of the substrate (or onto a previously formed layer or onto a
previously deposited portion of a layer) on which deposition is to
occur. The pressing together of the CC mask and substrate occur in
such a way that all openings, in the conformable portions of the CC
mask contain plating solution. The conformable material of the CC
mask that contacts the substrate acts as a barrier to
electrodeposition while the openings in the CC mask that are filled
with electroplating solution act as pathways for transferring
material from an anode (e.g. the CC mask support) to the
non-contacted portions of the substrate (which act as a cathode
during the plating operation) when an appropriate potential and/or
current are supplied.
[0023] An example of a CC mask and CC mask plating are shown in
FIGS. 1A-1C. FIG. 1A shows a side view of a CC mask 8 consisting of
a conformable or deformable (e.g. elastomeric) insulator 10
patterned on an anode 12. The anode has two functions. FIG. 1A also
depicts a substrate 6 separated from mask 8. One is as a supporting
material for the patterned insulator 10 to maintain its integrity
and alignment since the pattern may be topologically complex (e.g.,
involving isolated "islands" of insulator material). The other
function is as an anode for the electroplating operation. CC mask
plating selectively deposits material 22 onto a substrate 6 by
simply pressing the insulator against the substrate then
electrodepositing material through apertures 26a and 26b in the
insulator as shown in FIG. 1B. After deposition, the CC mask is
separated, preferably non-destructively, from the substrate 6 as
shown in FIG. 1C. The CC mask plating process is distinct from a
"through-mask" plating process in that in a through-mask plating
process the separation of the masking material from the substrate
would occur destructively. As with through-mask plating, CC mask
plating deposits material selectively and simultaneously over the
entire layer. The plated region may consist of one or more isolated
plating regions where these isolated plating regions may belong to
a single structure that is being formed or may belong to multiple
structures that are being formed simultaneously. In CC mask plating
as individual masks are not intentionally destroyed in the removal
process, they may be usable in multiple plating operations.
[0024] Another example of a CC mask and CC mask plating is shown in
FIGS. 1D-1F. FIG. 1D shows an anode 12' separated from a mask 8'
that includes a patterned conformable material 10' and a support
structure 20. FIG. 1D also depicts substrate 6 separated from the
mask 8'. FIG. 1E illustrates the mask 8' being brought into contact
with the substrate 6. FIG. 1F illustrates the deposit 22' that
results from conducting a current from the anode 12' to the
substrate 6. FIG. 1G illustrates the deposit 22' on substrate 6
after separation from mask 8'. In this example, an appropriate
electrolyte is located between the substrate 6 and the anode 12'
and a current of ions coming from one or both of the solution and
the anode are conducted through the opening in the mask to the
substrate where material is deposited. This type of mask may be
referred to as an anodeless INSTANT MASK.TM. (AIM) or as an
anodeless conformable contact (ACC) mask.
[0025] Unlike through-mask plating, CC mask plating allows CC masks
to be formed completely separate from the fabrication of the
substrate on which plating is to occur (e.g. separate from a
three-dimensional (3D) structure that is being formed). CC masks
may be formed in a variety of ways, for example, a
photolithographic process may be used. All masks can be generated
simultaneously, prior to structure fabrication rather than during
it. This separation makes possible a simple, low-cost, automated,
self-contained, and internally-clean "desktop factory" that can be
installed almost anywhere to fabricate 3D structures, leaving any
required clean room processes, such as photolithography to be
performed by service bureaus or the like.
[0026] An example of the electrochemical fabrication process
discussed above is illustrated in FIGS. 2A-2F. These figures show
that the process involves deposition of a first material 2 which is
a sacrificial material and a second material 4 which is a
structural material. The CC mask 8, in this example, includes a
patterned conformable material (e.g. an elastomeric dielectric
material) 10 and a support 12 which is made from deposition
material 2. The conformal portion of the CC mask is pressed against
substrate 6 with a plating solution 14 located within the openings
16 in the conformable material 10. An electric current, from power
supply 18, is then passed through the plating solution 14 via (a)
support 12 which doubles as an anode and (b) substrate 6 which
doubles as a cathode. FIG. 2A illustrates that the passing of
current causes material 2 within the plating solution and material
2 from the anode 12 to be selectively transferred to and plated on
the cathode 6. After electroplating the first deposition material 2
onto the substrate 6 using CC mask 8, the CC mask 8 is removed as
shown in FIG. 2B. FIG. 2C depicts the second deposition material 4
as having been blanket-deposited (i.e. non-selectively deposited)
over the previously deposited first deposition material 2 as well
as over the other portions of the substrate 6. The blanket
deposition occurs by electroplating from an anode (not shown),
composed of the second material, through an appropriate plating
solution (not shown), and to the cathode/substrate 6. The entire
two-material layer is then planarized to achieve precise thickness
and flatness as shown in FIG. 2D. After repetition of this process
for all layers, the multi-layer structure 20 formed of the second
material 4 (i.e. structural material) is embedded in first material
2 (i.e. sacrificial material) as shown in FIG. 2E. The embedded
structure is etched to yield the desired device, i.e. structure 20,
as shown in FIG. 2F.
[0027] Various components of an exemplary manual electrochemical
fabrication system 32 are shown in FIGS. 3A-3C. The system 32
consists of several subsystems 34, 36, 38, and 40. The substrate
holding subsystem 34 is depicted in the upper portions of each of
FIGS. 3A-3C and includes several components: (1) a carrier 48, (2)
a metal substrate 6 onto which the layers are deposited, and (3) a
linear slide 42 capable of moving the substrate 6 up and down
relative to the carrier 48 in response to drive force from actuator
44. Subsystem 34 also includes an indicator 46 for measuring
differences in vertical position of the substrate which may be used
in setting or determining layer thicknesses and/or deposition
thicknesses. The subsystem 34 further includes feet 68 for carrier
48 which can be precisely mounted on subsystem 36.
[0028] The CC mask subsystem 36 shown in the lower portion of FIG.
3A includes several components: (1) a CC mask 8 that is actually
made up of a number of CC masks (i.e. submasks) that share a common
support/anode 12, (2) precision X-stage 54, (3) precision Y-stage
56, (4) frame 72 on which the feet 68 of subsystem 34 can mount,
and (5) a tank 58 for containing the electrolyte 16. Subsystems 34
and 36 also include appropriate electrical connections (not shown)
for connecting to an appropriate power source for driving the CC
masking process.
[0029] The blanket deposition subsystem 38 is shown in the lower
portion of FIG. 3B and includes several components: (1) an anode
62, (2) an electrolyte tank 64 for holding plating solution 66, and
(3) frame 74 on which the feet 68 of subsystem 34 may sit.
Subsystem 38 also includes appropriate electrical connections (not
shown) for connecting the anode to an appropriate power supply for
driving the blanket deposition process.
[0030] The planarization subsystem 40 is shown in the lower portion
of FIG. 3C and includes a lapping plate 52 and associated motion
and control systems (not shown) for planarizing the
depositions.
[0031] Another method for forming microstructures from
electroplated metals (i.e. using electrochemical fabrication
techniques) is taught in U.S. Pat. No. 5,190,637 to Henry Guckel,
entitled "Formation of Microstructures by Multiple Level Deep X-ray
Lithography with Sacrificial Metal layers". This patent teaches the
formation of metal structure utilizing mask exposures. A first
layer of a primary metal is electroplated onto an exposed plating
base to fill a void in a photoresist, the photoresist is then
removed and a secondary metal is electroplated over the first layer
and over the plating base. The exposed surface of the secondary
metal is then machined down to a height which exposes the first
metal to produce a flat uniform surface extending across the both
the primary and secondary metals. Formation of a second layer may
then begin by applying a photoresist layer over the first layer and
then repeating the process used to produce the first layer. The
process is then repeated until the entire structure is formed and
the secondary metal is removed by etching. The photoresist is
formed over the plating base or previous layer by casting and the
voids in the photoresist are formed by exposure of the photoresist
through a patterned mask via X-rays or UV radiation.
[0032] Electrochemical Fabrication can be used to form structures
of complex shape using electrodepositable materials but a need
exists for reliable, cost effective, and improved ways of packaging
such objects.
SUMMARY OF THE INVENTION
[0033] An object of various aspects of the invention is to provide
improved packaging methods for critical structures.
[0034] Another object of various aspects of the invention is to
provide methods for concurrently fabricating structures and their
packaging.
[0035] Another object of various aspects of the invention is to
provide hermetically sealed structures.
[0036] Other objects and advantages of various aspects of the
invention will be apparent to those of skill in the art upon review
of the teachings herein. The various aspects of the invention, set
forth explicitly herein or otherwise ascertained from the teachings
herein, may address any one of the above objects alone or in
combination, or alternatively may not address any of the objects
set forth above but instead address some other object ascertained
from the teachings herein. It is not intended that all of these
objects be addressed by any single aspect of the invention even
though that may be the case with regard to some aspects.
[0037] In a first aspect of the invention an electrochemical
fabrication process for producing a three-dimensional structure
from a plurality of adhered layers includes: (A) depositing at
least a portion of a layer onto the substrate, wherein the
substrate may comprise previously deposited material; and (B)
forming a plurality of layers such that each successive layer is
formed adjacent to and adhered to a previously deposited layer;
wherein the layers comprise at least three different materials and
wherein the layers contain patterns of material comprising: (1) a
desired structural component that is to be protected and that is
formed from at least one structural material; (2) a protective
enclosure that is formed at least in part from a structural
material, wherein at least one portion of the enclosure at least
partially surrounds the desired structural component, and wherein
the enclosure is limited by at least one opening therein; (3) a
sealing material located near the at least one opening; and (4) a
sacrificial material located at least partially between the desired
structural component to be protected and at least a portion of the
enclosure; wherein after formation of the layers at least portion
of the sacrificial material located between the desired structural
component and at least a portion of the enclosure is removed; and
wherein after the removal of the sacrificial material, the sealing
material is made to temporarily flow and seal at least one opening
to block or significantly limit a passage of material from an
outside of the enclosure to an inside of the enclosure via the at
least one sealed opening.
[0038] In a second aspect of the invention an electrochemical
fabrication process for producing a three-dimensional structure
from a plurality of adhered layers, includes: (A) depositing at
least a portion of a layer onto a substrate, wherein the substrate
may comprise previously deposited material; and (B) forming a
plurality of layers such that each successive layer is formed
adjacent to and adhered to a previously deposited layer; wherein
the layers comprise at least two different materials and wherein
the layers contain patterns of material comprising: (1) a desired
structural component that is to be protected and that is formed
from at least one structural material; (2) a protective enclosure
that is formed at least in part from a structural material, wherein
at least one portion of the enclosure at least partially surrounds
the desired structural component, and wherein the enclosure is
limited by at least one opening therein; (3) a sacrificial material
located at least partially between the desired structural component
to be protected and at least a portion of the enclosure; wherein
after formation of the layers at least portion of the sacrificial
material located between the desired structural component and at
least a portion of the enclosure is removed; and wherein after the
removal of the sacrificial material, a seal is formed between the
protective enclosure and a sealing structure wherein at least one
of the protective enclosure or sealing structure comprises a
sealing material that may be used in establishing a sealing of the
at least one opening to block or significantly limit a passage of
material from an outside of the enclosure to an inside of the
enclosure via the at least one sealed opening.
[0039] In a third aspect of the invention an electrochemical
fabrication process for producing a three-dimensional structure
from a plurality of adhered layers includes: (A) depositing at
least a portion of a layer onto a substrate, wherein the substrate
may comprise previously deposited material; and (B) forming a
plurality of layers such that each successive layer is formed
adjacent to and adhered to a previously deposited layer; wherein
the layers comprise at least two different materials and wherein
the layers contain patterns of material comprising: (1) a desired
structural component that is to be protected and that is formed
from at least one structural material; (2) a protective enclosure
that is formed at least in part from a structural material, wherein
at least one portion of the enclosure at least partially surrounds
the desired structural component, and wherein the enclosure is
limited by at least one opening therein; (3) at least one blocking
structure located along a line of sight that includes the at least
one opening but spaced from the protective enclosure; and (4) a
sacrificial material located at least partially between the desired
structural component to be protected and at least a portion of the
enclosure; (5) wherein after formation of the layers at least
portion of the sacrificial material located between the desired
structural component and at least a portion of the enclosure is
removed; and (6) wherein after the removal of the sacrificial
material, a sealing material is deposited such that it strikes said
blocking material which inhibits the sealing material from entering
the enclosure in bulk, where by continued build up of the sealing
material seals the at least one opening to block or significantly
limit a passage of material from an outside of the enclosure to an
inside of the enclosure via the at least one sealed opening.
[0040] In a fourth aspect of the invention, an electrochemical
fabrication process for producing a three-dimensional structure
from a plurality of adhered layers includes (A) depositing at least
a portion of a layer onto a substrate, wherein the substrate may
comprise previously deposited material; and (B) forming a plurality
of layers such that each successive layer is formed adjacent to and
adhered to a previously deposited layer; wherein the layers
comprise at least two different materials and wherein the layers
contain patterns of material comprising: (1) a desired structural
component that is to be protected and that is formed from at least
one structural material; (2) a protective enclosure that is formed
at least in part from a structural material, wherein at least one
portion of the enclosure at least partially surrounds the desired
structural component, and wherein the enclosure is limited by at
least one opening therein; and (3) a sacrificial material located
at least partially between the desired structural component to be
protected and at least a portion of the enclosure.
[0041] Further aspects of the invention will be understood by those
of skill in the art upon reviewing the teachings herein. Other
aspects of the invention may involve combinations of the above
noted aspects of the invention and/or addition of various features
of one or more embodiments. Other aspects of the invention may
involve apparatus that can be used in implementing one or more of
the above method aspects of the invention. These other aspects of
the invention may provide various combinations of the aspects
presented above as well as provide other configurations,
structures, functional relationships, and processes that have not
been specifically set forth above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIGS. 1A-1C schematically depict side views of various
stages of a CC mask plating process, while FIGS. 1D-G schematically
depict a side views of various stages of a CC mask plating process
using a different type of CC mask.
[0043] FIGS. 2A-2F schematically depict side views of various
stages of an electrochemical fabrication process as applied to the
formation of a particular structure where a sacrificial material is
selectively deposited while a structural material is blanket
deposited.
[0044] FIGS. 3A-3C schematically depict side views of various
example subassemblies that may be used in manually implementing the
electrochemical fabrication method depicted in FIGS. 2A-2F.
[0045] FIGS. 4A-4F schematically depict the formation of a first
layer of a structure using adhered mask plating where the blanket
deposition of a second material overlays both the openings between
deposition locations of a first material and the first material
itself
[0046] FIG. 4G depicts the completion of formation of the first
layer resulting from planarizing the deposited materials to a
desired level.
[0047] FIGS. 4H and 4I respectively depict the state of the process
after formation of the multiple layers of the structure and after
release of the structure from the sacrificial material.
[0048] FIG. 5A depicts a block diagram of the basic steps of a
first group of embodiments.
[0049] FIG. 5B presents the basic steps of a second group of
embodiments in the form of a block diagram.
[0050] FIGS. 6A-6C depict a side view of various stages in the
production of a structure according to a preferred embodiment of
the invention.
[0051] FIG. 6D depicts a top view of the upper two layers of the
structure of FIG. 6B separated and then overlaid.
[0052] FIGS. 7A and 7B depict to alternative configurations of the
sealing layer of FIG. 6B
[0053] FIG. 8A depicts a side view of an alternative configuration
for the final two layers of FIG. 6B while 8B depicts a top view of
the upper two layers of the alternative structure first separated
one from the other and then overlaid.
[0054] FIGS. 9A-9D depict side views and top views illustrating
features of an alternative opening and sealing configuration for an
enclosing wall.
[0055] FIGS. 10A-10H depict various alternative opening and sealing
configurations.
[0056] FIGS. 11A-11C depict various alternative opening and sealing
configurations.
[0057] FIGS. 12A-12C depict various alternative opening and sealing
configurations.
[0058] FIGS. 13A and 13B depict an alternative opening and sealing
technique.
[0059] FIGS. 14A and 14B depict an alternative technique for
sealing openings.
[0060] FIGS. 15A-15F depict side views of various states of an
alternative embodiment for packaging a structure.
[0061] FIGS. 16A-16E depict side views of various states of another
embodiment for packaging a structure.
[0062] FIGS. 17A and 17B depict side views associated with an
alternative configuration for removing sacrificial material and for
sealing a package.
[0063] FIGS. 18A-18B depict side views for an alternative
configuration for removing sacrificial material and for sealing a
package.
[0064] FIG. 18C depicts a side top view corresponding the enclosure
and lid of FIG. 18A
[0065] FIG. 18D depicts a side view for an alternative
configuration for removing sacrificial material and for sealing a
package.
[0066] FIGS. 19A-19B depict two examples of alternative techniques
for forming conductive elements that extend through a hermetic
sealing enclosure.
DETAILED DESCRIPTION
[0067] FIGS. 1A-1G, 2A-2F, and 3A-3C illustrate various features of
one form of electrochemical fabrication. Other electrochemical
fabrication techniques are set forth in the '630 patent referenced
above, in the various previously incorporated publications, in
various other patents and patent applications incorporated herein
by reference. Still others may be derived from combinations of
various approaches described in these publications, patents, and
applications, or are otherwise known or ascertainable by those of
skill in the art from the teachings set forth herein. All of these
techniques may be combined with those of the various embodiments of
various aspects of the invention to yield enhanced embodiments.
Still other embodiments may be derived from combinations of the
various embodiments explicitly set forth herein.
[0068] FIGS. 4A-4I illustrate various stages in the formation of a
single layer of a multi-layer fabrication process where a second
metal is deposited on a first metal as well as in openings in the
first metal so that the first and second metal form part of the
layer. In FIG. 4A a side view of a substrate 82 is shown, onto
which patternable photoresist 84 is cast as shown in FIG. 4B. In
FIG. 4C, a pattern of resist is shown that results from the curing,
exposing, and developing of the resist. The patterning of the
photoresist 84 results in openings or apertures 92(a)-92(c)
extending from a surface 86 of the photoresist through the
thickness of the photoresist to surface 88 of the substrate 82. In
FIG. 4D a metal 94 (e.g. nickel) is shown as having been
electroplated into the openings 92(a)-92(c). In FIG. 4E the
photoresist has been removed (i.e. chemically stripped) from the
substrate to expose regions of the substrate 82 which are not
covered with the first metal 94. In FIG. 4F a second metal 96 (e.g.
silver) is shown as having been blanket electroplated over the
entire exposed portions of the substrate 82 (which is conductive)
and over the first metal 94 (which is also conductive). FIG. 4G
depicts the completed first layer of the structure which has
resulted from the planarization of the first and second metals down
to a height that exposes the first metal and sets a thickness for
the first layer. In FIG. 4H the result of repeating the process
steps shown in FIGS. 4B-4G several times to form a multi-layer
structure are shown where each layer consists of two materials. For
most applications, one of these materials is removed as shown in
FIG. 4I to yield a desired 3-D structure 98 (e.g. component or
device).
[0069] The various embodiments, alternatives, and techniques
disclosed herein may be used in combination with electrochemical
fabrication techniques that use different types of patterning masks
and masking techniques or even techniques that perform direct
selective depositions without the need for masking. For example,
conformable contact masks and masking operations may be used,
proximity masks and masking operations (i.e. operations that use
masks that at least partially selectively shield a substrate by
their proximity to the substrate even if contact is not made) may
be used, non-conformable masks and masking operations (i.e. masks
and operations based on masks whose contact surfaces are not
significantly conformable) may be used, and adhered masks and
masking operations (masks and operations that use masks that are
adhered to a substrate onto which selective deposition or etching
is to occur as opposed to only being contacted to it) may be
used.
[0070] FIG. 5A presents the basic steps of a first group of
embodiments of the invention in the form of a block diagram. Block
102 calls for the formation of a group of electrochemically
fabricated layers that include: (1) structural component(s) that
are to be protected; (2) a protective enclosure formed from a
structural material but having at least one opening therein; (3) a
sealing material located near the at least one opening; and (4) a
sacrificial material located at least partially between the
structure to be protected and the protecting enclosure. The
electrochemical fabrication process used may be similar to the one
illustrated in FIGS. 1A-1C and 2A-2F or it may be another process
set forth in the '630 patent, a process set forth in one of the
other previously incorporated publications, a process described in
one of the patents or applications that is included in the listing
of incorporated patents and applications set forth hereafter, or
the process may be a combination of various approaches described in
these publications, patents, and applications, or otherwise known
or ascertainable by those of skill in the art.
[0071] After the layers are formed the process proceeds to block
104 which calls for the removal of the sacrificial material.
[0072] Next, at block 106, the process calls for the optional
evacuation of the region(s) between the enclosure and the structure
to be protected. The process may also include the back filling of
the regions with a desired fill gas. The fill gas, for example, may
be inert (e.g. N2, Ar, or the like) or it may be chemically active
such as providing a reducing environment (e.g. H2) The process may
also include some special processing that is useful for preparing
the structure/enclosure combination for the next operation.
[0073] Finally, at block 108, the sealing material is temporarily
made to flow and to close the at least one opening.
[0074] FIGS. 6A-6C present side views of various stages of the
process flow of FIG. 5A as applied to a specific structure. FIG. 6A
depicts the group of layers 112 electrochemically fabricated and
attached to a substrate 114. The group of layers includes (1) a
structural component 122 that is to be protected and formed from a
structural material; (2) a protective enclosure 124 formed from a
structural material but having multiple openings 126 therein; (3) a
sealing material 128 located near the openings; and (4) a
sacrificial material 132 that fills the interior 134 (i.e. cavity)
of the enclosure 124.
[0075] FIG. 6B depicts the substrate 114, the enclosure 124, the
structural component 122, and the sealing material 128 after
removal of the sacrificial material but before flowing, sealing,
and resolidification of the sealing material. The sacrificial
material is preferably removed by etching with the etchant entering
the cavity through the opening in the enclosure.
[0076] FIG. 6C depicts the substrate 114, the enclosure 124, the
structural component 122, and the sealing material 128 after
flowing, sealing, and resolidification of the sealing material. In
this embodiment, the structural component becomes protected within
the package defined by the enclosure and the substrate. In the
present embodiment the sealing material is preferably a low melting
temperature electroplatable metal or solder-like material such as
Indium (In) or Tin (Sn)/Lead (Pb). The sacrificial material may be
copper and the structural material may be nickel, though of course
other appropriate materials would be acceptable. The requirement
being that the etching of the sacrificial material should not
damage the structural component 122 or significant damage the
sealing material 128.
[0077] FIG. 6D depicts a top view of the upper most layers of FIG.
6B. The left most component 142 is the second to last layer which
is the lid of enclosure 124 and which is made from the structural
material and which includes openings 126. Component 144 is the last
layer of the structure and is made from a sealing material 128. It
also includes openings 126. Component 144 is surrounded by a dashed
boundary line 148 which illustrates the outer boundary of component
142 when the two components are aligned. Component 146 shows a top
view of the two components 142 and 144 overlaid with the openings
124 aligned.
[0078] FIGS. 7A and 7B depict to alternative configurations of the
sealing layer of FIG. 6B. In FIG. 7A the sealing material include a
single cross-bar 152 that bridges the openings as it is believed
that such a bridge might aid in closing the opening when the
sealing material is made to flow (e.g. by heating sufficiently).
FIG. 7B is similar to FIG. 7A with the exception that two crossed
bridging elements 154 and 156 are depicted.
[0079] FIG. 8A depicts a side view of an alternative configuration
for the final two layers of FIG. 6B while 8B depicts a top view of
the last two layers including the alternative sealing layer. The
second to last layer 142 has not changed its configuration from
that which was depicted in FIG. 6D whereas the final layer 144' has
been modified. Instead of the last layer being configured as a
rectangular plate with holes in it as was the case in FIGS. 6A-6D,
in FIGS. 8A and 8B the sealing material around each opening is in
the form a ring as can be best seen in FIG. 8B and more
particularly the rings have smaller inner diameter than do the
holes 126 in layer 142. It is believed that the partial overlap of
the sealing material with the holes 126 in layer 142 will aid in
causing the material to fill in and seal the openings when the
sealing material is made to flow.
[0080] FIG. 9A depicts a side view of an enclosure that is formed
from a structural material with the exception of the third to last
layer from the top which is a sealing material layer 162. The
sealing material layer is shown from a top view in FIG. 9B where a
plurality of openings 126' through the sealing layer can be seen.
Upon flowing of the sealing material it is believe that the
material will spread and collapse to bridge the openings and seal
them. The collapse of the sealing layer can be seen in the side
view of FIG. 9C. The spreading of the sealing material and the
closing of the openings can be seen in the top view of FIG. 9D
wherein the dashed structures represent the original configuration
of sealing material layer 162 and the spread out material 166 the
new configuration after flowing. In alternative embodiments, the
collapse of the sealing layer and the spread of sealing material
may be aided by application of a pressure or force to the upper
portion of the structure.
[0081] FIG. 10A depicts a thickness (e.g. 1 or more layers) of an
enclosure 172 made from a structural material and having an opening
174 therein with sloped faces 176. A sealing material layer 178 is
shown above the layer of structural material. The sloped faces 176
are shown with stair steps though in some embodiments they may be
more truly of a sloped configuration. It is believed that the
sloping (or small stair steps) may help the flowable sealing
material wet the surface of the opening 174 when the sealing
material is made to flow and thus will aid in the closure of the
opening. FIG. 10B shows the resulting closure of the opening of
FIG. 10A after the sealing material is made to flow and allowed to
resolidify.
[0082] FIG. 10C shows the a top view of an opening of FIG. 10A when
the opening is circular in nature and the stair steps are circles
of progressively varying inner diameter. FIG. 10D depicts another
alternative to the openings of FIG. 10A where the openings are
indicated to be substantially circular but with radial openings cut
through which increase the size of the opening for improved entry
of etchant and removal of sacrificial material but still not
forming such a large opening that the sealing material would have a
difficult time bridging the gaps. FIG. 10E is analogous to FIGS.
10C and 10D but for rectangular holes as opposed to circular holes.
Though the openings in FIG. 10E are shown almost as square in
shape, in actual practice they may be elongated with slopes on each
side of the elongated openings. If elongated the slots through the
stair steps may be increased in number.
[0083] FIG. 10F shows an alternative configuration for the sealing
material 178 in relation to an opening 174 in the enclosure
structure 172. The sealing materials extend symmetrically beyond
the edges of each side of the upper portion of the opening in
enclosure 172. It is believed that such a configuration will aid in
the closure of the hole once the material is made to flow. FIG. 10G
depicts an alternative configuration to that of FIG. 10F in that a
portion of the overhanging sealing material is made to extend
substantially beyond the midpoint of opening and preferably
substantially over the lower portion of the structure bounding the
opposite side of the opening such that when the flowable material
is heated it may flow and collapse on the far side of the opening
and thereby sealing it. FIG. 10H is a further alternative to the
configuration of 10F in that the structural material is formed in
such away that that the opening through the structural material is
non-symmetric and as with FIG. 10G is not centered with the opening
in the sealing material 178. FIG. 10I depicts a further alternative
where the overhanging portion includes a bulge 180 of sealing
material attached thereto. It is believed that this bulge of
material will be useful in aiding the closure of the opening once
the sealing material is made to flow. In other alternatives, the
bulge of material may be extended to largely cover the entire right
side of the sloped surface
[0084] FIG. 11A depicts five layers of structural material 181-185
forming a portion of an enclosure and having an opening 186
therein. The structural layers are configured to have a protrusion
188 jutting into the opening. Above the protrusion is a quantity of
sealing material 192. Once the sealing material is made flowable it
is believed that the protrusion 188 will help force the sealing
material to bridge the gap in this narrowed region and will help
hold the sealing material in place once contact between the sides
is made. In this embodiment as well as in others, it may be
particularly useful to treat the enclosure with a reducing gas or
other activation process after removing the sacrificial material
but before the sealing material is made to flow. The activation of
the surface may help in causing the flowable sealing material to
wet the surface of the structural material. In particular, if the
structural material is subjected to activation, and the activation
is initiated from one side of the opening, it may be desirable to
have the sealing material toward the opposite side of the opening
as it may be anticipated that side nearest the initiation will be
more highly activated and thus the flowing material will have a
tendency to move in that direction as it wets the surface of the
structural material. As such, if the sealing material is toward the
inside of the enclosure, and activation is initiated from outside
the enclosure, the higher level of activation may be toward the
outer extends of the opening and the flowing of the material will
be encourage to move in the right direction for sealing the
opening.
[0085] FIG. 11B depicts an alternative configuration for the
sealing material. This alternative configuration may keep the
sealing material from having to flow across any unwetted structural
material surfaces in that the sealing material is deposited over
the protrusions and thus need only internally bulge due to surface
tension forces. In embodiments of this type, it may not be
necessary or desirable to activate the surfaces of the structural
material. FIG. 11C depicts another alternative where a bulge of
sealing material is provided within a pocket 194 adjacent to the
opening. It is believed that such a pocket of material adjacent to
thinner regions 196 of sealing material might tend to draw material
from those thinner regions as surface tension drives the sealing
material to minimize its surface area thus increasing the bulging
of the pocket to help seal the opening.
[0086] FIGS. 12A-12C depict before and after versions of deposited
and flowed sealing material for different potential opening
configurations. In these configurations the structural material is
given reference numeral 202 and the deposited sealing material is
given reference numeral 204 and the flowed sealing material is
given reference numeral 204'.
[0087] FIG. 5B presents the basic steps of a second group of
embodiments of the invention in the form of a block diagram. In
this Figure like elements to those in FIG. 5A are given like
reference numerals. Block 102', calls for the formation of a group
of electrochemically fabricated layers that include: (1) structural
component(s) that are to be protected; (2) a protective enclosure
formed from a structural material but having at least one opening
therein; and (3) a sacrificial material located at least partially
between the structure to be protected and the protecting enclosure.
Block 102' also indicates that the formed layers may also include a
sealing material located near the at least one opening.
[0088] After the layers are formed the process proceeds to block
104 which calls for the removal of the sacrificial material. This
may be performed in any manner that allows selective removal of the
sacrificial material without damaging the structural material (e.g.
by selective chemical etching or melting).
[0089] Next, at block 106, the process calls for the optional
evacuation of the region(s) between the enclosure and the structure
to be protected. The process may also include the back filling of
the regions with a desired fill gas. The fill gas, for example, may
be inert (e.g. N2, Ar, or the like) or it may be chemically active
such as providing a reducing environment (e.g. H2) The process may
also include some special processing that is useful for preparing
the structure/enclosure combination for the next operation.
[0090] Next, the process moves forward to block 110 which calls for
moving a sealing structure into position relative to the rest of
the enclosure. The sealing structure may include a sealing
material. Typically at least one of the layers formed or the
structure will include a sealing material. One of the enclosure or
the sealing structure may also or alternatively include an
adhesive. The movement of the sealing structure may be by
translation, rotation, or some combination thereof. The movement
may occur, for example, by pushing with a structure, by air
pressure, by collapse as the sacrificial material is removed, by
movement induced by stresses built in during layer-by-layer
formation, by causing a phase change or the like to occur that
causes a relative motion to result, or the like.
[0091] Finally, at block 108', the sealing material is temporarily
made to flow while the enclosure and sealing structure are brought
or held together.
[0092] FIGS. 13A and 13B depict an example according to one of the
embodiments of the group outlined in FIG. 5B. FIG. 13A depicts a
lid 212 located above the walls 214. The walls are topped with
sealing material 216. After removal of any sacrificial material
(not shown) the lid is brought down into position and the sealing
material 216 is made to flow (e.g. by the lid being heated). The
sealing material is compressed and forms seals between the lid and
the walls. The lid 212 may be made by an electrochemical
fabrication process or be made in some other manner. The lid may be
of a different material than the rest of the enclosure. The lid may
be a dielectric or even a transparent material.
[0093] In some embodiments, like that shown in FIGS. 13A and 13B
the walls of the enclosure are co-fabricated with the structure but
the lid is not. The walls may or may not have etching holes in
them. The last layer of the structure formed may have a sealant
applied (e.g. some type of solder) which may or may not be
planarized. After etching to release the structure in the box, the
separately fabricated lid (e.g. a metal sheet of some kind) is
placed over the build. This may be done at the wafer scale or on
individual devices. The solder (or other material) is made to flow
and the device is sealed. This approach offers several advantages:
(1) the devices or structures can be easily, visually examined
prior to sealing; (2) additional processing (e.g., metallization,
passivation, testing, etc.) may be performed prior to sealing; (3)
release etching will be less problematic; (4) problems with the
application or planarization of the flowable material may be
minimized; (5) it may be cheaper since one or more EFAB produced
layers can be eliminated by use of an essentially unpatterned
sheet, (6) the lid may be made of a material that is not easily
electrodeposited; and (7) wetting of the wall surfaces and lid
surface by the solder become less critical as a result of being
able to press the lid and the wall surfaces together.
[0094] In some alternative embodiments, the solder (or other
flowable sealing material) may be deposited onto the lid as opposed
to on the walls.
[0095] Many alternatives to the above noted embodiments are
possible and many additional embodiments will be apparent to those
of skill in the art. Multiple structural materials may be used.
Multiple types of flowable materials may be used. Structural
component(s) and enclosures may be formed from different materials
or even multiple materials. One or more of the flowable materials
may be used for sealing while others may be used for causing
displacement of structures relative to one another and thus may aid
in the automatic sealing of structures after removal of any
sacrificial materials. Interconnects may be fed through the
enclosures or the substrate so that electric connection to the
structure inside the enclosure can be established. Lid structures
or substrates may have openings covered by transparent windows such
that optical components may be embedded inside the enclosures and
optical signals transmitted into and out of the enclosures. The
substrate may include a conductively coated transparent structure
(e.g. glass) where the coating may be removed in conjunction with
the removal of the sacrificial material or be removed subsequent to
the removal of the sacrificial material. Alternatively, a
sufficiently conductive and optically transmitive coating may be
applied to a transparent substrate such as glass, quartz, and the
like.
[0096] In still other embodiments of the invention electrical
connects may be made through a lid or last layer of structural
material forming the enclosure. Examples of such electrical
connections are illustrated in FIGS. 19A and 19B. FIG. 19A
illustrates an embodiment where electrical connections to region
outside enclosure 606 are made via isolated conductive regions 622
in lid 612. Regions 622 are isolated from other conductive elements
of the lid (assuming the lid is formed from primarily a conductive
material) by dielectric rings 624. In other alternative embodiments
entire lid may be conductive with the exception of conductive
element 622. When lid 612 is bonded to enclosure 606 via sealing
material 616, compliant contacts 626 are pressed against regions
622 to make electric contact therewith. Contacts 626 are connected
via conductive columns 628 and horizontal leads 630 to selected
portions of structure 602. As such signals from structure 602 may
be carried outside enclosure 606/622 or signals may be carried to
structure 602 from external devices. In some alternative
embodiments, for example, columns 628 may be mounted on lid 612 and
compliant contacts 626 ma be located at the bottom of the columns
and be made to contact pads located on the floor of enclosure 606
or directly onto desired portions of structure 602. In still other
embodiments, the compliant contact elements may take on other
structural configurations as opposed to being simple cantilever
elements.
[0097] FIG. 19B depicts a configuration similar to that of FIG. 19A
with the exception that instead of using compliant contacts 626 for
making pressure connections, connections to conductive elements 622
are made via bonding material 642 that is made to bond elements 622
and columns 628. Alternatives similar to those noted above with
regard to FIG. 19A may form alternatives to this example
embodiment.
[0098] In still other embodiments, for example, capacitive or
inductive connections may be made between inside and outside
portions of the enclosure. In still other embodiments, radiative
transfer may be used to transfer signals and/or power to or from
the enclosed structure 602
[0099] Various techniques may be used to improve and supplement the
processes described above.
[0100] In some alternative embodiments, hermetic enclosures may be
made as discussed herein above where the hermeticity of
electrodeposited material, or material deposited in another manner,
may be enhanced. Such enhancement in hermeticity may result in
modified structures that are formed via modified processes. For
example, in some embodiments, instead of forming a lid or other
sealing structure or other portion of an enclosure from a single
layer of electrodeposited material, the lid or structure may be
formed from two or more electrodeposited layers with each having a
fraction of the layer thickness of the single layer and having a
total thickness similar to that of the single layer (e.g. the
portion of the enclosure may have an overall thickness that is not
greater than a maximum thickness of any layer from which the
structure is formed and yet it may be formed as multiple layers
instead of as a single layer. The creation of a desired thickness
from a plurality of adhered layers instead of from a single layer
may result in better hermeticity by reducing likelihood of
significant imperfections overlying one another. In some
alternative embodiments each of the plurality of overlying layers
may be planarized resulting in a smearing and sealing of any minor
imperfections. In still other embodiments, a single layer may be
converted into multiple layers where one or more of the layers is
formed via a different deposition process than the other layers
(e.g. one layer may be formed via sputtering while the other layers
may be formed via electrodeposition operations). The alternatively
deposited material may be applied to a previously planarized layer
or to an unplanarized layer. The alternatively deposited material
may be formed of a different material than the other deposited
materials.
[0101] Improved hermeticity of relative narrow features extending
multiple layers (e.g. walls) may be improved by using layer
interlacing techniques as set forth in U.S. patent application Ser.
No. 10/434,519, which is hereby incorporated herein by reference
where the interlaced regions may be formed as elongated elements
that extend around the length of a wall (e.g. an inner perimeter,
and outer perimeter, or along a line that lies internal to the
length of the wall.
[0102] IR reflow may be used to make heating more uniform and to
minimize the heating of the structures to be protected (e.g.
devices) and the substrate. In this process an IR source larger
than the substrate is placed parallel to the solder layer and at a
fixed distance. The substrate can be relatively translated in
perpendicular to the plane of the layers (i.e. along the z-axis) to
bring it into proximity with the IR source or it can be moved on a
conveyor past the source or it can be fixed in place before heat is
applied.
[0103] An alternative heating approach involves the use of a hot
plate. In this approach, the solder layer or lid of structural
material contacting the solder is brought into actual contact with
a hot plate. The plate could be treated to improve the wetting of
the solder. The plate may be brought into contact by translation
along the z-axis, and may be removed by lateral translation. In a
more extreme case, the plate could carry the solder and the
packaging layer would not have to be plated with solder. In an
alternative to the use of the hot plate it may be possible to bring
the layer with openings into contact with molten sealing material
(e.g. solder that has been made molten) which will wet and cling to
the surface when it is moved away and will seal the opening(s).
[0104] Various surface treatments may be used to improve the
wetting of the sealing material (e.g. solder) to the structural
material. Chemical treatments may be used such as fluxes, resins,
surface activators. It is also possible for Electro-chemical and
plasma treatments to be used. It may be possible to add surface
treatment chemicals to the etchant that is used to remove the
sacrificial material.
[0105] Reduction processes may be used to reduce oxide layers that
can impede the flow of the sealing material and thus improve
wetting. As an implementation example, before sealing material is
made to flow, a reducing atmosphere (e.g., hydrogen) is provided.
The sealing material is held below its melting point until oxide
layers are fully reduced. The reducing atmosphere may then be
replaced with an inert gas (e.g. N2). The inert gas may then be
evacuated to create an evacuated space or it may be retained. While
the enclosure remains evacuated or filled with a desired gas, the
temperature may be increased to the reflow temperature or to
desired temperature above the reflow temperature such that flowing
of the sealing material results in sealing after which the
temperature may be reduced to allow solidification of the molten
sealing material.
[0106] In some embodiments wicking structures may be used to aid in
the flow of sealing material. Ideally, openings should be sized and
located to give the maximum area for etchant flow, but provide the
minimum challenge for wetting with sealing material. Circular
openings may not be optimal and long narrow openings (slots) or
star shapes may be better, but still other alternatives may exist.
Circular opening can be made more likely to occlude (i.e. seal) by
adding wetting structures. A simple wetting structure is a line
that bisects the opening as was illustrate in FIG. 7A. The line may
be in either of the structural material or the sealing material or
in both (e.g. adjacent to one another). The line may arch out of
the planes of the layers or otherwise be of a non-linear shape
(e.g. curved or of varying dimension). A more complex wetting
structure may have one or more concentric rings connected by one or
more sets of lines (e.g. two sets of bisecting lines).
[0107] In still other embodiments, it may be possible to perform a
deposition to fill the holes, particularly if such a deposition is
essentially a straight line deposition process and if underneath
the holes a structural element is located that can act as a
deposition stop and build up point from which the deposit can build
up to seal the openings. This is illustrated with the aid of FIGS.
14A and 14B. FIG. 14A depicts a wall or lid of a packaging
structure 302 below which a component to be sealed exists (not
shown). The wall or lid contains openings 304 below which blocking
elements 306 exist. Any sacrificial material located below the wall
or lid 302 is removed, at least in part, via openings 304. After
removal, the package may be filled with a desired gas or other
material or it may remain evacuated. A substantially or at least
largely straight line deposition process (e.g. via PVD) may be used
to deposit sufficient material into the holes such the holes become
sealed. Such sealing is illustrated in FIG. 14B via the deposition
of material 308. In FIG. 14B the deposition of material 308 is
indicated as being selectively applied. In other alternatives, the
material may be deposited in a blanket fashion.
[0108] In other embodiments, to enhance the hermetic sealing of a
solder-type sealer, it may be possible to perform a PVD or other
deposition operation over the sealed openings to deposit a material
tends to be more hermetic in its properties (e.g. metal or glass).
In still other embodiments it may be possible to perform an
electrodeposition operation over the solder sealed openings to
enhance the sealing. In other embodiments, a sealed package may
include a getter material.
[0109] Another embodiment is explained the aid of FIGS. 15A-15F. In
FIG. 15A, a device 424 (e.g., a capacitor as shown here) has been
fabricated, top layer first, on a metallic release layer 408 (e.g.,
low-melting point solder) applied to a temporary substrate 402. In
FIG. 15B, prior to attachment of the final substrate, the
sacrificial material 420 has been partly etched. As much etching is
done as is possible at this time, though preferably not so much as
to completely release the device inside the package, since the
device as a whole and its individual components may then shift from
their intended positions. To allow for prolonged etching, each
independent element of the device may be provided with an anchoring
segment (not shown or required in this example) which extends
upwards so that it is embedded within the sacrificial material
during this initial etch, if the element otherwise (e.g., due to
its relatively short height) would become unanchored. In
embodiments where structures are otherwise joined to the side walls
complete etching may be acceptable.
[0110] In FIG. 15C, the structure has been adhered to a final
substrate 432 that is coated with an adhesive layer 438 (unless the
substrate is made from a thermoplastic or other material which can
itself adhere to the structural material). The adhesive is
preferably of a type that allows for a hermetic or near-hermetic
seal to be achieved, and preferably has good adhesion to the
structural material.
[0111] In FIG. 15D, the release layer is shown as having been
removed (e.g., by melting if a solder) and the temporary substrate
has been removed (if necessary, any residue of the release layer
can be removed by etching, lapping, polishing, etc.). In FIG. 15E,
the remaining sacrificial material has been etched through the
holes in the package. In FIG. 15F, the solder (typically with a
higher melting point than the solder used for the release layer) is
melted to seal the device (this step is normally performed within a
heated chamber filled with the desired gas or within a vacuum
chamber).
[0112] Another embodiment is illustrated in FIG. 16A-16E. In this
embodiment, individual isolated elements of the structure
(component, device, etc.) are anchored to other elements and the
inside surfaces of the package so as to allow complete etching of
the sacrificial material while isolated element retain their
positions. Only a single small hole 446 is required to be sealed by
solder 450 (in some alternatives multiple holes may be supplied),
and this hole, along with the adjacent solder, is not required if
the interior of the package can be air at atmospheric pressure (vs.
an inert gas or a vacuum, for example), or if the operation of
attaching the structure 424 and enclosure 462 to the final
substrate 480 can be accomplished while in an environment of a
desired gas or a vacuum. The only remaining purpose for the hole
and solder is to allow the internal atmosphere of the package to be
created after `substrate swapping` is completed. In FIG. 16A, a
device 424 has been fabricated, top layer first, on a metallic
release layer 474 (e.g., low-melting point solder) applied to a
temporary substrate 444. High-aspect ratio `pillars` 456 of
high-melting point solder (in fact, a low-melting point solder can
also be used, in which case the pillars will detach during step
leading to the state depicted in FIG. 16D, vs. during a separation
operation depicted as being completed in FIG. 16E) have been
provided to anchor the individual elements of the device during the
subsequent etch. In FIG. 16B, prior to attachment of the final
substrate 480, the sacrificial material 468 has been completely
etched. In FIG. 16C, the structure has been adhered to a final
substrate that is coated with an adhesive layer 486. In FIG. 16D,
the release layer 474 is shown as being removed or otherwise being
made to release its grip on temporary substrate 444 and the
temporary substrate is shown as being removed. In FIG. 16E, the
higher-melting point solder 456 is melted to seal the device and to
cause the pillars to `ball up` since they become unstable when
melted due to their high aspect ratio (length/diameter).
[0113] Another group of embodiments provide enclosure with moveable
attached sealing structures (e.g. lids). In these embodiments the
sealing structure is initially located to allow etching and is then
moved or dropped into sealing position. The attachment of the
sealing structure to the enclosure allows the lid to remain
attached to the enclosure during etching and possibly to thereafter
be positioned with enhanced alignment. In some embodiments, the
attachment elements may be supplemented by one or more alignment
elements. In some of these embodiments one or more attachment
elements and/or alignment elements may be used. In some
embodiments, these attachment and/or alignment elements may be
located on the perimeter of the enclosure and/or sealing structure.
In some alternative embodiments, they may be located to the
interior of the perimeter of the enclosure or sealing
structure.
[0114] In some embodiments, movement of the sealing structure
relative to the enclosure may cause alignment or attachment
elements to progress further into the interior of the enclosure
thereby necessitating existence of sufficient clearance between the
elements and the structure (device) to be packaged. In some
alternatives the alignment and/or attachment elements may be
mounted on the enclosure itself and thereby not cause a shrinking
of the interior space of the enclosure as sealing occurs.
[0115] An example of a structure configured and packaged according
to this group of embodiments is depicted in FIGS. 17A and 17B which
schematically depict side views of a package and structure in a
pre-sealed state and a sealed state. FIG. 17A depicts a sealing
structure or lid element 508 having an attachment element 510. The
lid element 508 is spaced from an enclosure 506 which is mounted to
a substrate 502 which together define an interior region 514 in
which a structure 504 is located. The attachment element 510
protrudes through an opening in a retainment structure which forms
part of enclosure 506. Lid 508 and/or enclosure 506 (both as
depicted) include a sealing material 512 (e.g. solder or a sealable
adhesive). FIG. 17B depicts the enclosure and lid after they have
been mated. The sealing material may then be melted or otherwise
made to seal the enclosure.
[0116] In the depicted example, the flow passages for etching the
structure are located along the perimeter of the enclosure. This
may be acceptable in some embodiments, but if the enclosure is
relatively wide excess of etchant only from the edges or perimeter
of the structure may cause problems (e.g. slow etching time, damage
to the perimeter of the structure as a result of exposure to
etchant, and the like). In other embodiments other passage and
sealing configurations are possible (e.g. in which passages are
supplied throughout the interior portions of the lid).
[0117] The structure and enclosure or preferable upside down during
etching of the sacrificial material (e.g. copper) or are otherwise
subjected to different orientations. When all the sacrificial
material is etched, the lid is free to move and the structure and
enclosure are dried and may be laid right side up so the lid
"falls" into a seated position on top of a thin plated solder layer
as shown in FIG. 17B. Next the package is heated to form a solder
weld between lid and enclosure to complete the packaging. As
depicted both the lid and the enclosure could have perimeters of
solder plating so wetting of structural material is not
necessary.
[0118] FIGS. 18A-18D depict other alternative configurations that
may have utility in sealing enclosures. As noted above etching
holes located within the interior of a lid or enclosure can be
useful in decreasing time to etch and in some configurations such
holes need not be tied to a size that can be sealed by a filling
solder. FIG. 18A depicts an enclosure 522 having sealing material
524 located near openings that extend through holes 526. Moveably
attached to the enclosure is lid element 528 that is formed in
lower position and can be moved higher once etching has been
completed and it is desired to seal the structure. The lid element
includes openings 536 that extend through it and are offset
slightly from the openings 526. FIG. 18B depicts the enclosure and
lid when relatively positioned to yield a closed state at which
point sealing can occur. FIG. 18C shows a top view of the structure
of FIG. 18A wherein lid element 528 can be seen through the holes
506 that extend through enclosure 522. The holes 516 in lid 528 are
shown with dashed lines.
[0119] FIG. 18D shows an alternative configuration where the
attachment structures are located on the perimeter of the enclosure
538 and where enclosure portions 540 (forming a groove with a lip
to catch the lid 546), may include openings 544 that can aid in
providing excess to etchant.
[0120] In some alternative embodiments the packaging techniques
disclosed herein may be implemented without necessarily
hermetically sealing the structure within the enclosure.
[0121] In some alternative embodiments solder may be deposited or
formed in ways that minimum or even eliminate the need for it to be
planarized (e.g. possibly by selective deposition to heights lower
than the next planarization level or deposition in voids, etc.
[0122] In other alternative embodiments, the lids need not be
planar or feature less, the lids (i.e. the other half of the
enclosure may contain structural components that have been
electrochemically fabricated or that have been produced in some
other manner.
[0123] In other alternative embodiments, a lid may be placed over
an enclosure after etching away the sacrificial material and the
lid may be covered (particularly in the bridging region from the
lid to the enclosure) with an epoxy or other material to complete
the sealing operation. In other embodiments, the lid may be matted
to the enclosure via a tapered surface. In still other embodiments
the solder, other meltable materials, adhesive, and the like may be
used in establishing a preliminary bond or seal between the
enclosure and the lid while an over coating with an epoxy, or other
material (e.g. electrodeposited, sputtered, or other applied metal)
may be used to enhance the integrity of the packaging.
[0124] The patent applications and patents set forth below are
hereby incorporated by reference herein as if set forth in full.
The gist of each patent application or patent is included in the
table to aid the reader in finding specific types of teachings. It
is not intended that the incorporation of subject matter be limited
to those topics specifically indicated, but instead the
incorporation is to include all subject matter found in these
applications. The teachings in these incorporated applications can
be combined with the teachings of the instant application in many
ways: For example, enhanced methods of producing structures may be
derived from the combination of teachings, enhanced structures may
be obtainable, enhanced apparatus may be derived, and the like.
[0125] U.S. patent application Ser. No. 09/488,142, filed Jan. 20,
2000, and entitled "An Apparatus for Electrochemical Fabrication
Comprising a Conformable Mask" is a divisional of the application
that led to the above noted '630 patent. This application describes
the basics of conformable contact mask plating and electrochemical
fabrication including various alternative methods and apparatus for
practicing EFAB as well as various methods and apparatus for
constructing conformable contact masks.
[0126] U.S. Patent Application No. 60/415,374, filed on Oct. 1, and
2002, and entitled "Monolithic Structures Including Alignment
and/or Retention Fixtures for Accepting Components" is generally
directed to a permanent or temporary alignment and/or retention
structures for receiving multiple components are provided. The
structures are preferably formed monolithically via a plurality of
deposition operations (e.g. electrodeposition operations). The
structures typically include two or more positioning fixtures that
control or aid in the positioning of components relative to one
another, such features may include (1) positioning guides or stops
that fix or at least partially limit the positioning of components
in one or more orientations or directions, (2) retention elements
that hold positioned components in desired orientations or
locations, and (3) positioning and/or retention elements that
receive and hold adjustment modules into which components can be
fixed and which in turn can be used for fine adjustments of
position and/or orientation of the components.
[0127] U.S. Patent Application No. 60/464,504, filed on Apr. 21,
2003, and entitled "Methods of Reducing Discontinuities Between
Layers of Electrochemically Fabricated Structures" is generally
directed to various embodiments providing electrochemical
fabrication methods and apparatus for the production of
three-dimensional structures from a plurality of adhered layers of
material including operations or structures for reducing
discontinuities in the transitions between adjacent layers. Some
embodiments improve the conformance between a size of produced
structures (especially in the transition regions associated with
layers having offset edges) and the intended size of the structure
as derived from original data representing the three-dimensional
structures. Some embodiments make use of selective and/or blanket
chemical and/or electrochemical deposition processes, selective and
or blanket chemical and/or electrochemical etching process, or
combinations thereof. Some embodiments make use of multi-step
deposition or etching operations during the formation of single
layers.
[0128] U.S. Patent Application No. 60/468,979, filed on May 7,
2003, and entitled "EFAB With Selective Transfer Via Instant Mask"
is generally directed to three-dimensional structures that are
electrochemically fabricated by depositing a first material onto
previously deposited material through voids in a patterned mask
where the patterned mask is at least temporarily adhered to a
substrate or previously formed layer of material and is formed and
patterned onto the substrate via a transfer tool patterned to
enable transfer of a desired pattern of precursor masking material.
In some embodiments the precursor material is transformed into
masking material after transfer to the substrate while in other
embodiments the precursor is transformed during or before transfer.
In some embodiments layers are formed one on top of another to
build up multi-layer structures. In some embodiments the mask
material acts as a build material while in other embodiments the
mask material is replaced each layer by a different material which
may, for example, be conductive or dielectric.
[0129] U.S. Patent Application No. 60/469,053, filed on May 7,
2003, and entitled "Three-Dimensional Object Formation Via
Selective Inkjet Printing & Electrodeposition" is generally
directed to three-dimensional structures that are electrochemically
fabricated by depositing a first material onto previously deposited
material through voids in a patterned mask where the patterned mask
is at least temporarily adhered to previously deposited material
and is formed and patterned directly from material selectively
dispensed from a computer controlled dispensing device (e.g. an ink
jet nozzle or array or an extrusion device). In some embodiments
layers are formed one on top of another to build up multi-layer
structures. In some embodiments the mask material acts as a build
material while in other embodiments the mask material is replaced
each layer by a different material which may, for example, be
conductive or dielectric.
[0130] U.S. patent application Ser. No. 10/271,574, filed on Oct.
15, 2002, and entitled "Methods of and Apparatus for Making High
Aspect Ratio Microelectromechanical Structures" is generally
directed to various embodiments of the invention presenting
techniques for forming structures (e.g. HARMS-type structures) via
an electrochemical extrusion (ELEX.TM.) process. Preferred
embodiments perform the extrusion processes via depositions through
anodeless conformable contact masks that are initially pressed
against substrates that are then progressively pulled away or
separated as the depositions thicken. A pattern of deposition may
vary over the course of deposition by including more complex
relative motion between the mask and the substrate elements. Such
complex motion may include rotational components or translational
motions having components that are not parallel to an axis of
separation. More complex structures may be formed by combining the
ELEX.TM. process with the selective deposition, blanket deposition,
planarization, etching, and multi-layer operations of EFAB.TM..
[0131] U.S. Patent Application No. 60/435,324, filed on Dec. 20,
2002, and entitled "EFAB Methods and Apparatus Including Spray
Metal or Powder Coating Processes", is generally directed to
various embodiments of the invention presenting techniques for
forming structures via a combined electrochemical fabrication
process and a thermal spraying process. In a first set of
embodiments, selective deposition occurs via conformable contact
masking processes and thermal spraying is used in blanket
deposition processes to fill in voids left by selective deposition
processes. In a second set of embodiments, selective deposition via
a conformable contact masking is used to lay down a first material
in a pattern that is similar to a net pattern that is to be
occupied by a sprayed metal. In these other embodiments a second
material is blanket deposited to fill in the voids left in the
first pattern, the two depositions are planarized to a common level
that may be somewhat greater than a desired layer thickness, the
first material is removed (e.g. by etching), and a third material
is sprayed into the voids left by the etching operation. The
resulting depositions in both the first and second sets of
embodiments are planarized to a desired layer thickness in
preparation for adding additional layers to form three-dimensional
structures from a plurality of adhered layers. In other
embodiments, additional materials may be used and different
processes may be used.
[0132] U.S. Patent Application No. 60/429,483, filed on Nov. 26,
2002, and entitled "Multi-cell Masks and Methods and Apparatus for
Using Such Masks to Form Three-Dimensional Structures" is generally
directed to multilayer structures that are electrochemically
fabricated via depositions of one or more materials in a plurality
of overlaying and adhered layers. Selectivity of deposition is
obtained via a multi-cell controllable mask. Alternatively, net
selective deposition is obtained via a blanket deposition and a
selective removal of material via a multi-cell mask. Individual
cells of the mask may contain electrodes comprising depositable
material or electrodes capable of receiving etched material from a
substrate. Alternatively, individual cells may include passages
that allow or inhibit ion flow between a substrate and an external
electrode and that include electrodes or other control elements
that can be used to selectively allow or inhibit ion flow and thus
inhibit significant deposition or etching.
[0133] U.S. Patent Application No. 60/429,484, filed on Nov. 26,
2002, and entitled "Non-Conformable Masks and Methods and Apparatus
for Forming Three-Dimensional Structures" is generally directed to
electrochemical fabrication used to form multilayer structures
(e.g. devices) from a plurality of overlaying and adhered layers.
Masks, that are independent of a substrate to be operated on, are
generally used to achieve selective patterning. These masks may
allow selective deposition of material onto the substrate or they
may allow selective etching of a substrate where after the created
voids may be filled with a selected material that may be planarized
to yield in effect a selective deposition of the selected material.
The mask may be used in a contact mode or in a proximity mode. In
the contact mode the mask and substrate physically mate to form
substantially independent process pockets. In the proximity mode,
the mask and substrate are positioned sufficiently close to allow
formation of reasonably independent process pockets. In some
embodiments, masks may have conformable contact surfaces (i.e.
surfaces with sufficient deformability that they can substantially
conform to surface of the substrate to form a seal with it) or they
may have semi-rigid or even rigid surfaces. Post deposition etching
operations may be performed to remove flash deposits (thin
undesired deposits).
[0134] U.S. patent application Ser. No. 10/309,521, filed on Dec.
3, 2002, and entitled "Miniature RF and Microwave Components and
Methods for Fabricating Such Components" is generally directed to
RF and microwave radiation directing or controlling components
provided that may be monolithic, that may be formed from a
plurality of electrodeposition operations and/or from a plurality
of deposited layers of material, that may include switches,
inductors, antennae, transmission lines, filters, and/or other
active or passive components. Components may include
non-radiation-entry and non-radiation-exit channels that are useful
in separating sacrificial materials from structural materials.
Preferred formation processes use electrochemical fabrication
techniques (e.g. including selective depositions, bulk depositions,
etching operations and planarization operations) and
post-deposition processes (e.g. selective etching operations and/or
back filling operations).
[0135] U.S. Patent Application No. 60/468,977, filed on May 7,
2003, and entitled "Method for Fabricating Three-Dimensional
Structures Including Surface Treatment of a First Material in
Preparation for Deposition of a Second Material" is generally
directed to a method of fabricating three-dimensional structures
from a plurality of adhered layers of at least a first and a second
material wherein the first material is a conductive material and
wherein each of a plurality of layers includes treating a surface
of a first material prior to deposition of the second material. The
treatment of the surface of the first material either (1) decreases
the susceptibility of deposition of the second material onto the
surface of the first material or (2) eases or quickens the removal
of any second material deposited on the treated surface of the
first material. In some embodiments the treatment of the first
surface includes forming a dielectric coating over the surface
while the deposition of the second material occurs by an
electrodeposition process (e.g. an electroplating or
electrophoretic process).
[0136] U.S. patent application Ser. No. 10/387,958, filed on Mar.
13, 2003, and entitled "Electrochemical Fabrication Method and
Apparatus for Producing Three-Dimensional Structures Having
Improved Surface Finish" is generally directed to an
electrochemical fabrication process that produces three-dimensional
structures (e.g. components or devices) from a plurality of layers
of deposited materials wherein the formation of at least some
portions of some layers are produced by operations that remove
material or condition selected surfaces of a deposited material. In
some embodiments, removal or conditioning operations are varied
between layers or between different portions of a layer such that
different surface qualities are obtained. In other embodiments
varying surface quality may be obtained without varying removal or
conditioning operations but instead by relying on differential
interaction between removal or conditioning operations and
different materials encountered by these operations.
[0137] U.S. patent application Ser. No. 10/434,289, filed on May 7,
2003, and entitled "Conformable Contact Masking Methods and
Apparatus Utilizing In Situ Cathodic Activation of a Substrate" is
generally directed to a electroplating processes (e.g. conformable
contact mask plating and electrochemical fabrication processes)
that includes in situ activation of a surface onto which a deposit
will be made are described. At least one material to be deposited
has an effective deposition voltage that is higher than an open
circuit voltage, and wherein a deposition control parameter is
capable of being set to such a value that a voltage can be
controlled to a value between the effective deposition voltage and
the open circuit voltage such that no significant deposition occurs
but such that surface activation of at least a portion of the
substrate can occur. After making electrical contact between an
anode, that comprises the at least one material, and the substrate
via a plating solution, applying a voltage or current to activate
the surface without any significant deposition occurring, and
thereafter without breaking the electrical contact, causing
deposition to occur.
[0138] U.S. patent application Ser. No. 10/434,294, filed on May 7,
2003, and entitled "Electrochemical Fabrication Methods With
Enhanced Post Deposition Processing" is generally directed to a
electrochemical fabrication process for producing three-dimensional
structures from a plurality of adhered layers is provided where
each layer comprises at least one structural material (e.g. nickel)
and at least one sacrificial material (e.g. copper) that will be
etched away from the structural material after the formation of all
layers have been completed. A copper etchant containing chlorite
(e.g. Enthone C-38) is combined with a corrosion inhibitor (e.g.
sodium nitrate) to prevent pitting of the structural material
during removal of the sacrificial material. A simple process for
drying the etched structure without the drying process causing
surfaces to stick together includes immersion of the structure in
water after etching and then immersion in alcohol and then placing
the structure in an oven for drying.
[0139] U.S. patent application Ser. No. 10/434,295, filed on May 7,
2003, and entitled "Method of and Apparatus for Forming
Three-Dimensional Structures Integral With Semiconductor Based
Circuitry" is generally directed to an enhanced electrochemical
fabrication processes that can form three-dimensional multi-layer
structures using semiconductor based circuitry as a substrate.
Electrically functional portions of the structure are formed from
structural material (e.g. nickel) that adheres to contact pads of
the circuit. Aluminum contact pads and silicon structures are
protected from copper diffusion damage by application of
appropriate barrier layers. In some embodiments, nickel is applied
to the aluminum contact pads via solder bump formation techniques
using electroless nickel plating. In other embodiments, selective
electroless copper plating or direct metallization is used to plate
sacrificial material directly onto dielectric passivation layers.
In still other embodiments, structural material deposition
locations are shielded, then sacrificial material is deposited, the
shielding is removed, and then structural material is
deposited.
[0140] U.S. patent application Ser. No. 10/434,315, filed on May 7,
2003, and entitled "Methods of and Apparatus for Molding Structures
Using Sacrificial Metal Patterns" is generally directed to molded
structures, methods of and apparatus for producing the molded
structures. At least a portion of the surface features for the
molds are formed from multilayer electrochemically fabricated
structures (e.g. fabricated by the EFAB.TM. formation process), and
typically contain features having resolutions within the 1 to 100
.mu.m range. The layered structure is combined with other mold
components, as necessary, and a molding material is injected into
the mold and hardened. The layered structure is removed (e.g. by
etching) along with any other mold components to yield the molded
article. In some embodiments portions of the layered structure
remain in the molded article and in other embodiments an additional
molding material is added after a partial or complete removal of
the layered structure.
[0141] U.S. patent application Ser. No. 10/434,493, filed on May 7,
2003, and entitled "Electrochemically Fabricated Structures Having
Dielectric or Active Bases and Methods of and Apparatus for
Producing Such Structures" is generally directed to multilayer
structures that are electrochemically fabricated on a temporary
(e.g. conductive) substrate and are thereafter bonded to a
permanent (e.g. dielectric, patterned, multi-material, or otherwise
functional) substrate and removed from the temporary substrate. In
some embodiments, the structures are formed from top layer to
bottom layer, such that the bottom layer of the structure becomes
adhered to the permanent substrate, while in other embodiments the
structures are form from bottom layer to top layer and then a
double substrate swap occurs. The permanent substrate may be a
solid that is bonded (e.g. by an adhesive) to the layered structure
or it may start out as a flowable material that is solidified
adjacent to or partially surrounding a portion of the structure
with bonding occurs during solidification. The multilayer structure
may be released from a sacrificial material prior to attaching the
permanent substrate or it may be released after attachment.
[0142] U.S. patent application Ser. No. 10/434,497, filed on May 7,
2003, and entitled "Multistep Release Method for Electrochemically
Fabricated Structures" is generally directed to multilayer
structures that are electrochemically fabricated from at least one
structural material (e.g. nickel), that is configured to define a
desired structure and which may be attached to a substrate, and
from at least one sacrificial material (e.g. copper) that surrounds
the desired structure. After structure formation, the sacrificial
material is removed by a multi-stage etching operation. In some
embodiments sacrificial material to be removed may be located
within passages or the like on a substrate or within an add-on
component. The multi-stage etching operations may be separated by
intermediate post processing activities, they may be separated by
cleaning operations, or barrier material removal operations, or the
like. Barriers may be fixed in position by contact with structural
material or with a substrate or they may be solely fixed in
position by sacrificial material and are thus free to be removed
after all retaining sacrificial material is etched.
[0143] U.S. patent application Ser. No. 10/434,519, filed on May 7,
2003, and entitled "Methods of and Apparatus for Electrochemically
Fabricating Structures Via Interlaced Layers or Via Selective
Etching and Filling of Voids" is generally directed to multi-layer
structures that are electrochemically fabricated by depositing a
first material, selectively etching the first material (e.g. via a
mask), depositing a second material to fill in the voids created by
the etching, and then planarizing the depositions so as to bound
the layer being created and thereafter adding additional layers to
previously formed layers. The first and second depositions may be
of the blanket or selective type. The repetition of the formation
process for forming successive layers may be repeated with or
without variations (e.g. variations in: patterns; numbers or
existence of or parameters associated with depositions, etchings,
and or planarization operations; the order of operations, or the
materials deposited). Other embodiments form multi-layer structures
using operations that interlace material deposited in association
with some layers with material deposited in association with other
layers.
[0144] Various other embodiments of the present invention exist.
Some of these embodiments may be based on a combination of the
teachings herein with various teachings incorporated herein by
reference. Some embodiments may not use any blanket deposition
process and/or they may not use a planarization process. Some
embodiments may involve the selective deposition of a plurality of
different materials on a single layer or on different layers. Some
embodiments may use blanket depositions processes that are not
electrodeposition processes. Some embodiments may use selective
deposition processes that are not contact masking processes and are
not even electrodeposition processes. Some embodiments may use
nickel as a structural material while other embodiments may use
different materials such as gold, silver, or any other
electrodepositable materials that can be separated from the copper
and/or some other sacrificial material. Some embodiments may use
copper as the structural material with or without a sacrificial
material. Some embodiments may remove a sacrificial material while
other embodiments may not. In some embodiments the anode may be
different from a contact mask support and the support may be a
porous structure or other perforated structure. Some embodiments
may use multiple conformable contact masks with different patterns
so as to deposit different selective patterns of material on
different layers and/or on different portions of a single layer. In
some embodiments, the depth of deposition will be enhanced by
pulling the conformable contact mask away from the substrate as
deposition is occurring in a manner that allows the seal between
the conformable portion of the CC mask and the substrate to shift
from the face of the conformal material to the inside edges of the
conformable material.
[0145] In view of the teachings herein, many further embodiments,
alternatives in design and uses of the invention will be apparent
to those of skill in the art. As such, it is not intended that the
invention be limited to the particular illustrative embodiments,
alternatives, and uses described above but instead that it be
solely limited by the claims presented hereafter.
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