U.S. patent application number 14/193725 was filed with the patent office on 2014-06-26 for debris removal in high aspect structures.
The applicant listed for this patent is Rave, LLC. Invention is credited to Bernabe J. Arruza, Tod Evan Robinson, Kenneth Gilbert Roessler.
Application Number | 20140176922 14/193725 |
Document ID | / |
Family ID | 40453164 |
Filed Date | 2014-06-26 |
United States Patent
Application |
20140176922 |
Kind Code |
A1 |
Robinson; Tod Evan ; et
al. |
June 26, 2014 |
Debris Removal in High Aspect Structures
Abstract
A system for removing debris from a surface of a
photolithographic mask is provided. The system includes an atomic
force microscope with a tip supported by a cantilever. The tip
includes a surface and a nanometer-scaled coating disposed thereon.
The coating has a surface energy lower than the surface energy of
the photolithographic mask.
Inventors: |
Robinson; Tod Evan; (Boynton
Beach, FL) ; Arruza; Bernabe J.; (Boca Raton, FL)
; Roessler; Kenneth Gilbert; (Boca Raton, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rave, LLC |
Delray Beach |
FL |
US |
|
|
Family ID: |
40453164 |
Appl. No.: |
14/193725 |
Filed: |
February 28, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13652114 |
Oct 15, 2012 |
8696818 |
|
|
14193725 |
|
|
|
|
11898836 |
Sep 17, 2007 |
8287653 |
|
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13652114 |
|
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Current U.S.
Class: |
355/30 |
Current CPC
Class: |
G03F 1/72 20130101; B03C
7/006 20130101; B08B 7/0028 20130101; G03F 7/70925 20130101; G03F
1/82 20130101; B08B 1/00 20130101 |
Class at
Publication: |
355/30 |
International
Class: |
G03F 7/20 20060101
G03F007/20 |
Claims
1. A system for removing debris from a surface of a
photolithographic mask, comprising: an atomic force microscope,
including: a cantilever, and a tip supported by the cantilever, the
tip including a surface and a nanometer-scaled coating disposed
thereon, the nanometer-scaled coating having a surface energy lower
than a surface energy of the photolithographic mask.
2. The system of claim 1, further comprising a pallet attached to a
stage that supports the photolithographic mask, and a material
disposed on the pallet, wherein the material is softer than the
tip.
3. The system of claim 1, wherein the nanometer-scaled coating is
polytetrafluoroethylene.
4. The system of claim 1, wherein the tip further includes at least
one fibril extending therefrom.
5. The system of claim 4, wherein the at least one fibril consists
of a plurality of fibrils.
6. The system of claim 4, wherein the at least one fibril is
configured to coil around a particle.
7. The system of claim 4, wherein the at least one fibril is
attached to a distal end of the tip.
8. The system of claim 2, wherein the tip includes a metallic
material disposed between the surface and the nanometer-scaled
coating.
9. The system of claim 2, wherein the tip includes an oxide
material disposed between the surface and the nanometer-scaled
coating.
10. The system of claim 2, wherein the tip includes a metal oxide
material disposed between the surface and the nanometer-scaled
coating.
11. A system for removing debris from a surface of a substrate,
comprising: an atomic force microscope, including: a cantilever,
and a tip supported by the cantilever, the tip including a surface
and a nanometer-scaled coating disposed thereon, the
nanometer-scaled coating having a surface energy lower than a
surface energy of the substrate.
12. The system of claim 11, further comprising a patch attached to
a stage that supports the substrate, and a material disposed on the
patch, wherein the material is softer than the tip.
13. The system of claim 11, wherein the nanometer-scaled coating is
polytetrafluoroethylene.
14. The system of claim 11, wherein the tip further includes at
least one fibril extending therefrom.
15. The system of claim 14, wherein the at least one fibril
consists of a plurality of fibrils.
16. The system of claim 14, wherein the at least one fibril is
configured to coil around a particle.
17. The system of claim 14, wherein the at least one fibril is
attached to a distal end of the tip.
18. The system of claim 12, wherein the tip includes a metallic
material disposed between the surface and the nanometer-scaled
coating.
19. The system of claim 12, wherein the tip includes an oxide
material disposed between the surface and the nanometer-scaled
coating.
20. The system of claim 12, wherein the tip includes a metal oxide
material disposed between the surface and the nanometer-scaled
coating.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/652,114 filed on Oct. 15, 2012, which is a continuation
of U.S. patent application Ser. No. 11/898,836 filed on Sep. 17,
2007 both of which are incorporated by reference in their entirety
for all purposes as if fully set forth herein.
FIELD OF THE INVENTION
[0002] The present invention relates generally to nanomachining
processes. More particularly, the present invention relates to
debris removal during and/or pursuant to nanomachining
processes.
BACKGROUND OF THE INVENTION
[0003] Nanomachining, by definition, involves mechanically removing
nanometer-scaled volumes of material from, for example, a
photolithography mask, a semiconductor substrate/wafer, or some
other monolith. For the purposes of this discussion, "substrate"
will refer to any object upon which nanomachining may be
performed.
[0004] Typically, nanomachining is performed by applying forces to
a surface of a substrate with a tip (e.g., a diamond cutting bit)
that is positioned on a cantilever arm of an atomic force
microscope (AFM). More specifically, the tip is typically first
inserted into the surface of the substrate. Then, the tip is
dragged through the substrate in a plane that is parallel to the
surface (i.e., the xy-plane). This results in displacement and/or
removal of material from the substrate as the tip is dragged
along.
[0005] As a result of this nanomachining, debris is generated on
the substrate. More specifically, small particles may form during
the nanomachining process as material is removed. These particles,
in some instances, remain on the substrate once the nanomachining
process is over. Such particles are often found, for example, in
trenches and/or cavities present on the substrate.
[0006] In order to remove such debris, particularly in high-aspect
photolithography mask structures and electronic circuitry, wet
cleaning techniques are often used. More specifically, the use of
chemicals in a liquid state and/or agitation of the overall mask or
circuitry is typically employed. However, both chemical methods and
agitation methods such as, for example, megasonic agitation, can
destroy both high-aspect ratio structures and mask optical
proximity correction features (i.e., features that are generally so
small that these features do not image, but rather form diffraction
patterns that are used beneficially by mask designers to form
patterns).
[0007] In order to better understand why high-aspect shapes and
structures are particularly susceptible to being destroyed by
chemicals and agitation, one has to recall that such shapes and
structures, by definition, include large amounts of surface area
and are therefore very thermodynamically unstable. As such, these
shapes and structures are highly susceptible to delamination and/or
other forms of destruction when chemical and/or mechanical energy
is applied.
[0008] In view of the above, other currently available methods for
removing debris from a substrate make use of cryogenic cleaning
systems and techniques. When employing such systems and techniques,
the substrate containing the high aspect shapes and/or structures
is effectively "sandblasted" using carbon dioxide particles instead
of sand.
[0009] Unfortunately, even cryogenic cleaning systems and processes
are also known to destroy high aspect features. In addition,
cryogenic cleaning processes affect a relatively large area of a
substrate (e.g., areas that may be approximately 10 millimeters
across or more). Naturally, this means that areas of the substrate
that may not need to have debris removed therefrom are nonetheless
exposed to the cleaning process and to the potential
structure-destroying energies associated therewith.
SUMMARY
[0010] At least in view of the above, what is needed are novel
debris-removal methods and devices that are capable of cleaning
substrates with high aspect structures, mask optical proximity
correction features, etc., without destroying such structures
and/or features.
[0011] According to one aspect of the present disclosure, a method
for removing debris from a trench formed on a photolithographic
mask is provided. The method includes positioning a tip within the
trench, moving the tip within the trench to physically adhere
debris to the tip, moving the tip with the adhered debris away from
the trench, and removing the adhered debris from the tip. The tip
includes a surface and a nanometer-scaled coating disposed thereon,
and the coating has a surface energy lower than the surface energy
of the photolithographic mask.
[0012] According to another aspect of the present disclosure, a
system for removing debris from a surface of a photolithographic
mask is provided. The system includes a pallet of soft material
attached to a stage that supports the photolithographic mask, and
an atomic force microscope including a tip, supported by a
cantilever, to indent the soft material. The tip includes a surface
and a nanometer-scaled coating disposed thereon, and the coating
has a surface energy lower than the surface energy of the
photolithographic mask.
[0013] According to another aspect of the present disclosure, a
system for removing debris from a surface of a photolithographic
mask is provided. The system includes an atomic force microscope
including a tip supported by a cantilever. The tip includes a
surface and a nanometer-scaled coating disposed thereon, and the
coating has a surface energy lower than the surface energy of the
photolithographic mask.
[0014] There has thus been outlined, rather broadly, certain
embodiments of the invention in order that the detailed description
thereof herein may be better understood, and in order that the
present contribution to the art may be better appreciated. There
are, of course, additional embodiments of the invention that will
be described below and which will form the subject matter of the
claims appended hereto.
[0015] In this respect, before explaining at least one embodiment
of the invention in detail, it is to be understood that the
invention is not limited in its application to the details of
construction and to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
invention is capable of embodiments in addition to those described
and of being practiced and carried out in various ways. Also, it is
to be understood that the phraseology and terminology employed
herein, as well as the abstract, are for the purpose of description
and should not be regarded as limiting.
[0016] As such, those skilled in the art will appreciate that the
conception upon which this disclosure is based may readily be
utilized as a basis for the designing of other structures, methods
and systems for carrying out the several purposes of the present
invention. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 illustrates a cross-sectional view of a portion of a
debris removal device according to an embodiment of the present
invention.
[0018] FIG. 2 illustrates a cross-sectional view of another portion
of the debris removal device illustrated in FIG. 1.
[0019] FIG. 3 illustrates a cross-sectional view of the portion of
the debris removal device illustrated in FIG. 1, wherein particles
are being imbedded in the patch.
[0020] FIG. 4 illustrates a cross-sectional view of the portion of
the debris removal device illustrated in FIG. 3, wherein the tip is
no longer in contact with the patch.
[0021] FIG. 5 illustrates a cross-sectional view of a tip according
to the present invention.
DETAILED DESCRIPTION
[0022] The invention will now be described with reference to the
drawing figures, in which like reference numerals refer to like
parts throughout. FIG. 1 illustrates a cross-sectional view of a
portion of a debris removal device 10 according to an embodiment of
the present invention. The device 10 includes a nanometer-scaled
tip 12 positioned adjacent to a patch 14 of low surface energy
material.
[0023] Formed on the tip 12 is a coating 16. Before forming the
coating 16, tip 12 may be pre-coated or otherwise surface treated
to modify the surface energy of the tip 12 (e.g., to modify the
capillary, wetting, and/or surface tension effects). When properly
selected, the coating 16 allows the tip 12 to remain sharper for a
longer period of time than an uncoated tip. For example, a
PTFE-coated diamond tip can have a longer operating life than an
uncoated diamond tip.
[0024] According to certain embodiments of the present invention,
the coating 16 includes the same low surface energy material found
in the patch 14. Also, according to certain embodiments of the
present invention, the tip 12 may be in direct contact with the
patch 14 and the coating 16 may be formed (or replenished) on the
surface of tip 12 by rubbing tip 12 against the patch 14.
Typically, rubbing tip 12 against the patch and/or scratching the
pad 14 also causes enhanced surface diffusion of the low surface
energy material over the surface of tip 12.
[0025] According to certain embodiments of the present invention,
the coating 16 and the patch 14 are both made from, or at least may
include, polytetrafluoroethylene (PTFE) or some other similar
material. According to other embodiments of the present invention,
a metallic material, oxide, metal oxide, or some other high surface
energy material may be disposed between the surface of tip 12 and
the low-surface energy material coating 16. Alternatively, the
surface of tip 12 may be roughened or doped. The high surface
energy material or tip treatment typically acts to bind the
low-surface energy material coating 16 to tip 12 more strongly.
[0026] A high-surface energy pre-treatment is used without a
low-surface energy coating 16 according to certain embodiments of
the present invention. In such embodiments, the particles 20
discussed below may be embedded in some other soft targets (e.g.,
Au, Al) using similar methods to those discussed herein, or the tip
may be a consumable. Also, other physical and/or environmental
parameters may be modified (e.g., temperature, pressure, chemistry,
humidity) to enhance tip treatment and/or particle
pick-up/drop-off
[0027] According to certain embodiments of the present invention,
all of the components illustrated in FIGS. 1 and 2 are included in
an AFM. In some such configurations, the patch 14 is substantially
flat and is attached to a stage that supports the substrate 18.
Also, according to certain embodiments of the present invention,
the patch 14 is removable from the stage and may easily be
replaced. For example, the patch 14 may be affixed to the AFM with
an easily releasable clamp (not illustrated).
[0028] FIG. 2 illustrates a cross-sectional view of another portion
of the debris removal device 10 illustrated in FIG. 1. Illustrated
in FIG. 2 is a substrate 18 that is typically positioned adjacent
to the patch 14 illustrated in FIG. 1. Also illustrated in FIG. 2
is a plurality of particles 20 that are present in a trench 22 that
is formed on the surface of the substrate 18. The particles 20 are
typically attached to the surface via Van der Waals short-range
forces. In FIG. 2, the tip 12 is positioned adjacent to the
substrate 18. In order to reach the bottom of the trench 22, the
tip 12 in the embodiment of the present invention illustrated in
FIGS. 1 and 2 is a high aspect ratio tip. Although a trench 22 is
illustrated in FIG. 2, the particles 20 may be included in other
structures.
[0029] FIG. 3 illustrates a cross-sectional view of the portion of
the debris removal device 10 illustrated in FIG. 1, wherein
particles 20 are being imbedded in the patch 14. Then, FIG. 4
illustrates a cross-sectional view of the portion of the debris
removal device 10 illustrated in FIG. 3, wherein the tip 12 is no
longer in contact with the patch 14.
[0030] According to certain embodiments of the present invention,
the device 10 illustrated in FIGS. 1-4 is utilized to implement a
method of debris removal. It should be noted that certain
embodiments of the present invention may be used in conjunction
with other particle cleaning processes, either prior or pursuant to
the method discussed herein. It should also be noted that, although
only one tip 12 is discussed herebelow, a plurality of tips may be
used to implement certain embodiments of the present invention. For
example, a plurality of tips could perform embodiments of the
methods discussed herein in parallel and at the same time.
[0031] The debris method mentioned above includes positioning the
tip 12 adjacent to one or more of the particles 20 (i.e., the
pieces of debris) illustrated as being on the substrate 18 in FIG.
2. Then, the method includes physically adhering (as opposed to
electrostatically adhering) the particles 20 to the tip 12 as also
illustrated in FIG. 2 as well as some possible repetitive motion of
the tip when in contact with the particle(s) and surrounding
surfaces. Pursuant to the physical adherence of the particles 20 to
the tip 12, the method includes removing the particles 20 from the
substrate 18 by moving the tip 12 away from the substrate 18, and
moving the particles 20 to the patch 14, as illustrated in FIG.
3.
[0032] According to certain embodiments of the present invention,
the method also includes forming the coating 16 on a portion of the
tip 12. According to some of these embodiments, the coating 16
includes a coating material that has a lower surface energy than
the substrate 18.
[0033] In addition to the above, some embodiments of the method
also include moving the tip 12 relative to the substrate 18 such
that the tip 12 is adjacent to other pieces of debris (not
illustrated). Then, these adhered other pieces of debris are
removed from the substrate 18 by moving the tip 12 away from the
substrate 18 in a manner analogous to what is shown in FIG. 3.
[0034] Once debris (e.g., the particles 20 discussed above, have
been removed from the substrate 18, some methods according to the
present invention include the step of depositing the piece of
debris in a piece of material positioned away from the substrate
(e.g., the above-discussed patch 14).
[0035] Because the tip 12 may be used repeatedly to remove large
amounts of debris, according to certain embodiments of the present
invention, the method includes replenishing the coating 16 by
plunging the tip 12 in the patch 14. In these embodiments, low
surface energy material from the patch would coat any holes or gaps
that may have developed in the coating 16 over time. This
replenishing may involve moving the tip 12 laterally within the
patch 14 pursuant to plunging the tip 12 in the patch, rubbing the
surface, or changing some other physical parameter (e.g.,
temperature).
[0036] It should be noted that certain methods according to the
present invention include exposing a small area around a defect or
particle to a low surface energy material before a repair in order
to reduce the likelihood that the removed material will lump
together and strongly adhere again to the substrate after the
repair is completed. For example, a defect/particle and a
approximately 1-2 micron area around the defect is pre-coated with
PTFE according to certain embodiments of the present invention. In
such instances, a tip 12 coated or constructed from a low surface
energy material (e.g., a PTFE tip) can be used to apply a very
generous amount of the low surface energy material to a repair area
even when other repair tools (laser, e-beam) are being
utilized.
[0037] According to certain embodiments of the present invention,
the method includes using the patch 14 to push the particles away
from the apex of the tip 12 and toward an AFM cantilever (not
illustrated) that is supporting the tip 12. Such pushing up of the
particles 20 would free up space near the apex of the tip 12
physically adhere more particles 20.
[0038] According to certain embodiments of the present invention,
the tip 12 is used to remove nanomachining debris from high aspect
ratio structures such as, for example, trench 22, by alternately,
"dipping" (or indenting) the tip 12 in a pallet of soft (i.e.,
"doughy") material, typically found in the patch 14. This soft
material generally has greater adherence to the tip 12 and debris
material (e.g., in the particles 20) than to itself. The soft
material may also be selected to have polar properties to
electrostatically attract the nanomachining debris particles 20 to
the tip 12. For example, a mobile surfactant may be used.
[0039] In addition to the above, according to certain embodiments
of the present invention, the tip 12 may include one or more
dielectric surfaces (i.e., electrically insulated surfaces). These
surfaces may be rubbed on a similarly dielectric surface in certain
environmental conditions (e.g., low humidity) to facilitate
particle pick-up due to electrostatic surface charging. Also,
according to certain embodiments of the present invention, the
coating 16 attracts particles by some other short-range mechanism
(e.g., hydrogen bonding, chemical reaction, enhanced surface
diffusion).
[0040] Any tip that is strong and stiff enough to penetrate (i.e.,
indent) the soft pallet material may be used. Hence, very high
aspect tip geometries are within the scope of the present
invention. Once the tip is stiff enough to penetrate the soft
(possibly adhesive) material, high aspect ratio tips that are
strong and flexible are generally selected over tips that are
weaker and/or less flexible. This allows for the boundaries of the
cleaning vector box to be larger than the repair. Hence, according
to certain embodiments of the present invention, the tip can be
rubbed into the sides and corners of the repair trench 22. A rough
macro-scale analogy of this operation is a stiff bristle being
moved inside a deep inner diameter. It should also be noted that,
according to certain embodiments of the present invention, the tip
12 may be selected to be more "bristle-like" by including a
plurality of rigid nanofibrils (e.g., carbon nanotubes, metal
whiskers, etc.). The tip 12 may alternatively be selected to be
more "mop-like" by including a plurality of flexible/limp
nanofibrils (e.g., polymers, etc.).
[0041] According to certain embodiments of the present invention,
the detection of whether or not one or more particles have been
picked up involves performing a noncontact AFM scan of the region
of interest (ROI) to detect particles. The tip 12 is then retracted
from the substrate without rescanning until after treatment at the
target. However, overall mass of debris material picked up by the
tip may also be monitored by relative shifts in the tip's resonant
frequency. In addition, other dynamics are used for the same
function.
[0042] Instead of indenting in a soft material to remove particles
20 as discussed above and as illustrated in FIG. 4, the tip 12 may
also be vectored into the patch 14 to remove the particles 20. As
such, if the tip inadvertently picks up a particle 20, the particle
20 can be removed by doing another repair. Particularly when a
different material is used for depositing the particles 20 by
vectoring, then a soft metal such as a gold foil may be used.
[0043] In addition to the above, an ultra-violet (UV)-light-curable
material, or similarly some other material susceptible to a
chemically nonreversible reaction, may be used to coat the tip 12
and to form the coating 16. Before the UV cure, the material picks
up particles 20 from the substrate 18. Once the tip 12 is removed
from the substrate 18, the tip 12 is exposed to a UV source where
the material's properties would be changed to make it less adherent
to the tip 12 and more adherent to the material in the patch 14,
where the. This, or some other, nonreversible process further
enhances, or enables, the selectivity of particle pick up and
removal.
[0044] Certain embodiments of the present invention provide a
variety of advantages. For example, certain embodiments of the
present invention allow for active removal of debris from high
aspect trench structures using very high aspect AFM tip geometries.
Also, certain embodiments of the present invention may be
implemented relatively easily by attaching a low surface energy or
soft material pallet to an AFM, along with using a very high aspect
tip and making relatively minor adjustments to the software repair
sequences currently used by AFM operators. In addition, according
to certain embodiments of the present invention, a novel
nanomachining tool may be implemented that could be used (like
nano-tweezers) to selectively remove particles from the surface of
a mask which could not be cleaned by any other method. This may be
combined with a more traditional repair where the debris would
first be dislodged from the surface with an uncoated tip, then
picked up with a coated tip.
[0045] Generally, it should be noted that, although a low surface
energy material is used in the local clean methods discussed above,
other possible variations are also within the scope of the present
invention. Typically, these variations create a surface energy
gradient (i.e., a Gibbs free energy gradient) that attracts the
particle 20 to the tip 12 and that is subsequently reversed by some
other treatment to release the particles 20 from the tip 12.
[0046] For example, one variation that may be used includes using a
high surface energy tip coating. Another variation includes
pretreating the particles with a low surface energy material to
debond the particles and then contacting the particles with a high
surface energy tip coating (sometimes on a different tip). Still
another variation includes making use of a chemical energy gradient
that corresponds to a chemical reaction occurring between a tip
surface coating and the particle surface to bond the two. This is
either performed until a tip is exhausted or reversed with some
other treatment.
[0047] According to still other embodiments of the present
invention, adhesives or sticky coatings are used in combination
with one or more of the above-listed factors. Also, the surface
roughness or small scale (e.g., nanometer-scale) texture can be
engineered to maximize particle clean process efficiency.
[0048] In addition to the above, mechanical bonding may be used,
typically when the tip 12 includes fibrils that, analogously to a
mop, are capable of mechanically entangling the particles 20. The
mechanical entanglement, according to certain embodiments of the
present invention, is driven by and/or enhanced by surface energy
or chemical changes with contact or environment.
[0049] According to still other embodiments of the present
invention, the tip 12 may be coated with molecular tweezers (i.e.,
molecular clips). These tweezers are noncyclic compounds with open
cavities capable of binding guests (e.g., the above-discussed
particles 20). The open cavity of the tweezers typically binds
guests using non-covalent bonding including hydrogen bonding, metal
coordination, hydrophobic forces, van der Waals forces, .pi.-.pi.
interactions, and/or electrostatic effects. These tweezers are
sometimes analogous to macrocyclic molecular receptors except that
the two arms that bind the guest molecules are typically only
connected at one end.
[0050] In addition to the above, the particles 20 may be removed by
the tip using diffusion bonding or Casimir effects. Also, as in the
embodiments of the present illustrated in FIG. 5, bristles or
fibrils 30 can be attached to the end of the tip 12. Whether
strategically or randomly placed, these bristles or fibrils 30 can
enhance local clean in several ways. For example, an associated
increase in surface area may be used for surface (short range)
bonding to the particles.
[0051] According to some of embodiments of the present invention,
fibrils 30 are engineered to be molecules that selectively (e.g.,
by either surface or environment) coil around and entangle a
particle 20, thus maximizing surface contact. Also, dislodging of
the particles 20 occurs according to certain embodiments of the
present invention, typically when stiff bristles 30 are attached to
the tip 12. However, fibrils 30 may also entangle a particle 20 and
dislodge the particle 20 mechanically by pulling on the particle
20. In contrast, relatively rigid bristles 30 typically allow the
tip 12 to extend into hard-to-reach crevices. Then, by impact
deformation stress of the bristles 30, by surface-modification of
the tip 12 to repel particles 20, or by some combination, the
particle 20 is dislodged. In addition, certain embodiments of the
present invention mechanically bond the particles 20 to the tip 12.
When fibrils are on the tip 12, entanglement of one or more of
either the whole or frayed fibrils may occur. When bristles are on
the tip 12, the particle 20 may be wedged between (elastically)
stressed bristles.
[0052] According to still other embodiments of the present
invention, methods of debris removal include changing the
environment to facilitate local clean. For example, gas or liquid
media may be introduced or the chemistry and/or physical properties
(e.g., pressure, temperature, humidity) may be changed.
[0053] In addition to the components discussed above, certain
embodiments of the present invention include an image recognition
system that identifies debris to be removed. As such, an automatic
debris-removal device is also within the scope of the present
invention.
[0054] According to certain embodiments of the present invention, a
relatively soft cleaning tip is used to avoid unwanted damage to
inside contours, walls, and/or bottom of a complex shape. When
appropriate, a stronger force is used to bring the relatively soft
tip into much stronger contact with the surface while also
increasing the scan speed.
[0055] It should also be noted that a tip exposed to and/or coated
with a low surface energy material can be used for other purposes
besides removing debris (cleaning) of nanometer level structures.
For example, such tips can also be used, according to certain
embodiments of the present invention, to periodically lubricate
micron level or smaller devices (like MEMS/NEMS) to contain
chemical reactions.
[0056] The many features and advantages of the invention are
apparent from the detailed specification, and thus, it is intended
by the appended claims to cover all such features and advantages of
the invention which fall within the true spirit and scope of the
invention. Further, since numerous modifications and variations
will readily occur to those skilled in the art, it is not desired
to limit the invention to the exact construction and operation
illustrated and described, and accordingly, all suitable
modifications and equivalents may be resorted to, falling within
the scope of the invention.
* * * * *