U.S. patent application number 13/923565 was filed with the patent office on 2013-10-31 for opto-electronic modules and methods of manufacturing the same and appliances and devices comprising the same.
The applicant listed for this patent is Heptagon Micro Optics Pte. Ltd.. Invention is credited to Markus Rossi, Hartmut Rudmann.
Application Number | 20130284906 13/923565 |
Document ID | / |
Family ID | 46614263 |
Filed Date | 2013-10-31 |
United States Patent
Application |
20130284906 |
Kind Code |
A1 |
Rudmann; Hartmut ; et
al. |
October 31, 2013 |
OPTO-ELECTRONIC MODULES AND METHODS OF MANUFACTURING THE SAME AND
APPLIANCES AND DEVICES COMPRISING THE SAME
Abstract
Manufacturing opto-electronic modules (1) includes providing a
substrate wafer (PW) on which detecting members (D) are arranged;
providing a spacer wafer (SW); providing an optics wafer (OW), the
optics wafer comprising transparent portions (t) transparent for
light generally detectable by the detecting members and at least
one blocking portion (b) for substantially attenuating or blocking
incident light generally detectable by the detecting members; and
preparing a wafer stack (2) in which the spacer wafer (SW) is
arranged between the substrate wafer (PW) and the optics wafer (OW)
such that the detecting members (D) are arranged between the
substrate wafer and the optics wafer. Emission members (E) for
emitting light generally detectable by the detecting members (D)
can be arranged on the substrate wafer (PW). Single modules (1) can
be obtained by separating the wafer stack (2) into separate
modules.
Inventors: |
Rudmann; Hartmut; (Jona,
CH) ; Rossi; Markus; (Jona, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Heptagon Micro Optics Pte. Ltd. |
Singapore |
|
SG |
|
|
Family ID: |
46614263 |
Appl. No.: |
13/923565 |
Filed: |
June 21, 2013 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
13553290 |
Jul 19, 2012 |
|
|
|
13923565 |
|
|
|
|
61509346 |
Jul 19, 2011 |
|
|
|
Current U.S.
Class: |
250/216 |
Current CPC
Class: |
B29D 11/00298 20130101;
B29D 11/00307 20130101; H01L 25/167 20130101; H01L 31/16 20130101;
G01J 1/0271 20130101; G01J 1/06 20130101; G01J 5/0265 20130101;
G01J 2001/061 20130101; G01J 5/045 20130101; H01L 27/14687
20130101; G02B 3/0056 20130101; G02B 13/0085 20130101; H01L 31/167
20130101; G01J 5/00 20130101; G01J 5/022 20130101; H01L 27/14618
20130101; G01J 1/0233 20130101; G01J 5/024 20130101; G01J 5/0806
20130101; H01L 27/14625 20130101; Y10T 29/49002 20150115; G01J
1/0209 20130101; G01J 1/42 20130101; G02B 3/0031 20130101; G01J
5/0235 20130101; H01L 2924/0002 20130101; H01L 31/02325 20130101;
G01J 1/0411 20130101; H01L 27/14627 20130101; G01J 5/20 20130101;
H01L 2924/0002 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
250/216 |
International
Class: |
H01L 31/16 20060101
H01L031/16 |
Claims
1. (canceled)
2. A proximity sensor module comprising: a substrate on which are
mounted a light emitter and a light detector; an optics member
disposed over the substrate and substantially parallel to the
substrate; a plurality of passive optical components disposed over
the light emitter on opposite sides of the optics member from one
another; a plurality of passive optical components disposed over
the light detector on opposite sides of the optics member from one
another; a baffle member over the optics member; an interior wall
at least partially separating an area of the module into which the
light emitter emits light from an area of the module from which the
light detector detects light, wherein the interior wall is composed
of a material that is substantially non-transparent to light
detectable by the light detector; and outside walls of the module,
wherein at least part of the outside walls are composed of a
material that is substantially non-transparent to light detectable
by the light detector.
3. The proximity sensor module of claim 2 wherein each of the
plurality of passive optical components over the light emitter and
the plurality of passive optical components over the light detector
comprises a lens.
4. The proximity sensor module of claim 2 including a spacer
between the substrate and the optics member.
5. The proximity sensor module of claim 4 wherein the spacer
encircles the light emitter and the light detector.
6. The proximity sensor module of claim 5 wherein the substrate and
the optics member are fixed to one another via the spacer.
7. The proximity sensor module of claim 4 wherein the spacer has a
plurality of openings, wherein the light emitter is arranged in one
of the openings and the light detector is arranged in another one
of the openings.
8. The proximity sensor module of claim 2 wherein the interior wall
includes a polymer material.
9. The proximity sensor module of claim 8 wherein at least parts of
the outside walls of the module include the same polymer material
as the interior wall.
10. The proximity sensor module of claim 9 wherein the baffle
member is composed of an epoxy material.
11. The proximity sensor module of claim 2 wherein at least parts
of the outside walls of the module include a polymer material.
12. The proximity sensor module of claim 2 wherein the baffle
member is composed of an epoxy material.
13. The proximity sensor module of claim 2 wherein the light
emitter is a light emitting diode and the light detector is a
photodiode.
14. The proximity sensor module of claim 13 wherein the light
emitting diode is disposed on the substrate so as to emit light in
a direction generally perpendicular to the substrate.
15. The proximity sensor module of claim 2 wherein the passive
optical components over the light emitter and the passive optical
components over the light detector are composed of a resin
material.
16. An opto-electronic sensor module comprising: a substrate on
which are mounted a light emitting diode and a photodiode, the
light emitting diode disposed to emit light in a direction
substantially perpendicular to a surface of the substrate on which
the light emitting diode is mounted; an optics member disposed over
the substrate and substantially parallel to the substrate; a
plurality of lenses disposed over the light emitting diode on
opposite sides of the optics member from one another; a plurality
of lenses disposed over the photodiode on opposite sides of the
optics member from one another; a baffle member over the optics
member and having openings over the lenses; an interior wall at
least partially separating an area of the module into which the
light emitting diode emits light from an area of the module from
which the photodiode detects light, wherein the interior wall is
composed of a material that is substantially non-transparent to
light detectable by the photodiode; and respective electrical
contacts for the light emitting diode and the photodiode are
connected to contacts on an outside surface of the module.
17. The opto-electronic sensor module of claim 16 including outside
walls of the module, wherein at least part of the outside walls are
composed of a material that is substantially non-transparent to
light detectable by the photodiode.
18. The opto-electronic sensor module of claim 17 wherein at least
parts of the outside walls of the module include a polymer
material, wherein the interior wall includes a polymer material,
wherein the baffle member is composed of an epoxy material, and
wherein the lenses over the light emitter and the lenses over the
light detector are composed of a resin material.
19. The opto-electronic sensor module of claim 18 wherein at least
portions of the optics member on which the lenses are disposed are
composed of a material substantially transparent to light emitted
by the light emitting diode and detectable by the photodiode.
20. The opto-electronic sensor module of claim 16 wherein the
contacts on the outside surface of the module are on an outside
surface of the substrate.
21. The opto-electronic sensor module of claim 20 wherein the
contacts are contact pads.
22. The opto-electronic sensor module of claim 16 including a
separation member between the substrate and the optics member.
23. The opto-electronic sensor module of claim 22 wherein the
separation member encircles the light emitting diode and the
photodiode.
24. The opto-electronic sensor module of claim 23 wherein the
substrate and the baffle member are fixed to one another via the
separation member.
25. The opto-electronic sensor module of claim 22 wherein the
separation member has a plurality of openings, wherein the light
emitting diode is arranged in one of the openings and the
photodiode is arranged in another one of the openings.
26. The opto-electronic sensor module of claim 16 wherein at least
either the interior wall or at least part of the outside walls of
the module are composed of a polymer material.
27. The opto-electronic sensor module 16 wherein the baffle member
is composed of an epoxy material.
28. A hand-held communication device comprising: a printed circuit
board; and a proximity sensor module mounted on the printed circuit
board, the proximity sensor module including: a substrate on which
are mounted a light emitter and a light detector; an optics member
disposed over the substrate and substantially parallel to the
substrate; a plurality of passive optical components disposed over
the light emitter on opposite sides of the optics member from one
another; a plurality of passive optical components disposed over
the light detector on opposite sides of the optics member from one
another; a baffle member over the optics member; and an interior
wall at least partially separating an area of the module into which
the light emitter emits light from an area of the module from which
the light detector detects light, wherein the interior wall is
composed of a material that is substantially non-transparent to
light detectable by the light detector.
29. The hand-held communication device of claim 28 wherein each of
the plurality of passive optical components over the light emitter
and the plurality of passive optical components over the light
detector comprises a lens.
30. The hand-held communication device of claim 28 wherein the
proximity sensor module includes a spacer between the substrate and
the optics member, wherein the spacer encircles the light emitter
and the light detector, and wherein the substrate and the baffle
member are fixed to one another via the spacer.
31. The hand-held communication device of claim 28 the proximity
sensor includes outer walls, at least parts of which are composed
of a material that is substantially non-transparent to light
detectable by the light detector, and wherein the passive optical
components over the light emitter and the passive optical
components over the light detector are composed of a resin
material.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a continuation of U.S. application Ser.
No. 13/553,290, filed Jul. 19, 2012, which claims priority to U.S.
Provisional Patent Application No. 61/509,346, filed on Jul. 19,
2011, the contents of which are incorporated herein by
reference.
TECHNICAL FIELD
[0002] This disclosure relates to the field of opto-electronics and
more specifically to the packaging and manufacturing of
opto-electronic components. More particularly, it relates to
opto-electronic modules and to methods of manufacturing the same
and to appliances and to electronic devices comprising such
modules, in particular wherein the modules comprise at least one
light detector. The
BACKGROUND
[0003] From US 2010/0327164 A1, an opto-electronic module, more
specifically a proximity sensor is known, during the manufacture of
which light emitter dice and light detector dice are overmolded
using transfer molding techniques so as to form lenses on these
dice.
[0004] In U.S. Pat. No. 5,912,872, an integrated optical apparatus
is presented. In the manufacture thereof, a support wafer having a
plurality of active elements thereon is aligned with a transparent
wafer having a corresponding plurality of optical elements. Such a
support-transparent wafer pair may then be diced apart.
[0005] In US 2011/0050979 A1, an optical module for an
electro-optical device with a functional element is disclosed. The
optical module includes a lens substrate portion with at least one
lens element, and a spacer. The spacer serves to keep the lens
substrate at a well-defined axial distance from a base substrate
portion of the fully assembled electro-optical device. In order to
ensure an improved performance of the functional element, an EMC
shield is provided. The spacer is at least in parts electrically
conductive and thus forms the EMC shield or a part thereof. A
method of manufacturing a plurality of such modules on a wafer
scale is also disclosed in US 2011/0050979 A1.
DEFINITION OF TERMS
[0006] "Active optical component": A light sensing or a light
emitting component. E.g., a photodiode, an image sensor, an LED, an
OLED, a laser chip.
[0007] "Passive optical component": An optical component
redirecting light by refraction and/or diffraction and/or
reflection such as a lens, a prism, a mirror, or an optical system,
wherein an optical system is a collection of such optical
components possibly also comprising mechanical elements such as
aperture stops, image screens, holders.
[0008] "Opto-electronic module": A component in which at least one
active and at least one passive optical component is comprised.
[0009] "Replication": A technique by means of which a given
structure or a negative thereof is reproduced. E.g., etching,
embossing, molding.
[0010] "Wafer": A substantially disk- or plate-like shaped item,
its extension in one direction (z-direction or vertical direction)
is small with respect to its extension in the other two directions
(x- and y-directions or lateral directions). For example, on a
(non-blank) wafer, a plurality of like structures or items are
arranged or provided therein, e.g., on a rectangular grid. A wafer
may have opening or holes, and a wafer may even be free of material
in a predominant portion of its lateral area. Although in many
contexts, a wafer is understood to be prevailingly made of a
semiconductor material, in the present patent application, this is
explicitely not a limitation. Accordingly, a wafer may prevailingly
be made of, e.g., a semiconductor material, a polymer material, a
composite material comprising metals and polymers or polymers and
glass materials. In particular, hardenable materials such as
thermally or UV-curable polymers are interesting wafer materials in
conjunction with the presented invention.
[0011] "Lateral": cf. "Wafer"
[0012] "Vertical": cf. "Wafer"
[0013] "Light": Most generally electromagnetic radiation; more
particularly electromagnetic radiation of the infrared, visible or
ultraviolet portion of the electromagnetic spectrum.
SUMMARY
[0014] Some implementations provide one or more of the following
advantages. For example, some implementations create an alternative
way of manufacturing opto-electronic modules. More particularly, a
particularly fast way of manufacturing opto-electronic modules
and/or a particularly simple way of manufacturing opto-electronic
modules can be provided. In addition, the respective
opto-electronic module, an electronic device comprising such an
opto-electronic module and an appliance comprising a multitude of
such opto-electronic modules can be provided.
[0015] Also, some implementations provide opto-electronic modules
having a particularly accurate alignment and a corresponding
manufacturing method.
[0016] Further, some implementations provide opto-electronic
modules of particularly small dimensions.
[0017] Some implmentations provide opto-electronic modules
comprising at least an active and possibly also a passive optical
component which are well protected against stray light and/or
cross-talk.
[0018] Also, some implementations provide particularly small
electronic devices comprising at least one opto-electronic
module.
[0019] According to one aspect, for example, a method for
manufacturing opto-electronic modules comprises:
[0020] a) providing a substrate wafer on which a multitude of
detecting members are arranged;
[0021] b) providing a spacer wafer;
[0022] c) providing an optics wafer, the optics wafer comprising a
multitude of transparent portions transparent for light generally
detectable by the detecting members and at least one blocking
portion for substantially attenuating or blocking incident light
generally detectable by the detecting members;
[0023] d) preparing a wafer stack in which the spacer wafer is
arranged between the substrate wafer and the optics wafer such that
the detecting members are arranged between the substrate wafer and
the optics wafer.
[0024] This may allow manufacturing of opto-electronic modules in a
particularly efficient way, and may allow manufacturing of
particularly small opto-electronic modules. Furthermore, light
incident on such a detecting member may be restricted to desired
light, and undesired light, i.e. light which should not reach the
detecting member, may be kept from reaching the detecting member,
as it may be absorbed by and/or reflected by the blocking portion.
For this purpose, the at least one blocking portion may be at least
substantially non-transparent for light detectable by the detecting
members.
[0025] The feature that the detecting members are arranged
"between" the substrate wafer and the optics wafer is to be
understood to comprise and to more precisely mean, respectively,
the case that the detecting members are comprised in the substrate
wafer and that there exists at least another portion of the
substrate wafer such that the detecting members are arranged
between that other portion of the substrate wafer and the optics
wafer.
[0026] In case the detection members are comprised in the substrate
wafer, one could rather and more clearly say that the wafer stack
(cf. step d)) is prepared such that the detection members are
arranged "on a side of the substrate facing the optics member",
instead of arranged "between the substrate wafer and the optics
wafer".
[0027] Nevertheless, the detection members may be comprised in the
substrate wafer or be not comprised in the substrated wafer.
[0028] It is to be noted that the transparency of the transparent
portions for light generally detectable by the detecting members
does not necessarily mean that the transparent portions have to be
transparent for any light generally detectable by the detecting
members. In some implementations, a transparency for a portion of
the light generally detectable by the detecting members is
sufficient.
[0029] Particularly, the substrate wafer is a wafer referred to as
substrate wafer, and the spacer wafer is a wafer referred to as
spacer wafer, and the optics wafer is a wafer referred to as optics
wafer.
[0030] The detecting member is a detector for detecting light, in
particular infrared light, more particularly near-infrared
light.
[0031] In some implementations, each of the wafers has a generally
plate-like shape and comprises a two-dimensional periodic
arrangement of structures or items.
[0032] In some embodiments, the detecting member is or comprises a
photodiode.
[0033] In some embodiments, which may be combined with the
before-addressed embodiment, step d) comprises fixing the substrate
wafer to the spacer wafer and fixing the spacer wafer to the optics
wafer. The fixing may in one or both cases be accomplished by
gluing.
[0034] In some embodiments, which may be combined with one or both
before-addressed embodiments, step d) comprises aligning the
substrate wafer and the optics wafer such that each of the
multitude of detecting members is aligned with respect to at least
one of the transparent portions, in particular wherein each of the
detecting members is aligned in the same way to one of the
transparent portions each.
[0035] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, step a) comprises the step
of
[0036] a1) placing the detecting members on the substrate wafer by
pick-and-place.
[0037] Carrying out such a pick-and-place operation on wafer-level
allows to achieve a high placing accuracy and a high manufacturing
speed.
[0038] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, step a) comprises the step
of
[0039] a2) electrically connecting each of the detection members to
the substrate wafer.
[0040] This can be accomplished, e.g., by die-bonding or by
soldering by reflowing.
[0041] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, each of the multitude of
transparent portions comprises at least one passive optical
component.
[0042] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises providing
a wafer which is a combination of the spacer wafer and the optics
wafer. Such a wafer can be referred to as "combined optics
wafer".
[0043] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises the step
of manufacturing the blocking portion and the spacer wafer as a
unitary part. This may, for example, be accomplished using
replication.
[0044] Combining wafers (and, correspondingly, the respective
members) can be accomplished with relatively few manufacturing
steps and, in particular, with relatively few alignment steps. This
may simplify manufacture and/or result in modules of higher
precision.
[0045] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, each of the multitude of
transparent portions comprises at least one passive optical
component such as a lens member (as an example for a passive
optical component), in particular wherein each of the passive
optical components comprises at least one optical structure, or
more particularly, wherein each of the lens members comprises at
least one lens element. Such a lens member is or comprises at least
one (optical) lens; and such a lens element is a lens which
possibly is a portion of a composed lens composed of at least two
transparent parts. The lens elements are provided for redirecting
light by diffraction or by refraction. More generally, the passive
optical component are provided for redirecting light by diffraction
and/or by refraction and/or by reflection.
[0046] In some embodiments, referring to the before-addressed
embodiment comprising lens elements, the lens elements are or at
least each of a portion of the lens elements is of generally convex
shape. Also, partially or generally concave shapes or other shapes,
e.g., combining concave and convex regions, are possible.
[0047] In some embodiments, referring to one or more of the
before-addressed embodiments comprising passive optical components,
each of the passive optical components or each of a portion of the
passive optical components is associated with at least one of the
detecting members each.
[0048] In some embodiments referring to one or more of the
before-addressed embodiments comprising lens members, each of the
lens members or each of a portion of the lens members is associated
with at least one of the detecting members each.
[0049] In some embodiments, referring to one or more of the
before-addressed embodiments comprising passive optical components
(such as lens members), the method comprises the step of
[0050] c1) manufacturing the passive optical components by means of
replication.
[0051] Replication can be a very efficient way of producing a
multitude of, e.g., lenses and lens elements, respectively. It may
be possible to save many alignment steps and/or a lot of
manufacturing time this way.
[0052] In some embodiments, referring to the before-addressed
embodiment, step c1) comprises replicating a surface in a liquid,
viscous or plastically deformable material and subsequently
hardening, in particular curing, the material. Suitable materials
can be, e.g., polymers such as epoxy resins.
[0053] In some embodiments, referring to the before-addressed
embodiment, replicating the surface comprises embossing the surface
into the material.
[0054] In some embodiments, referring to one or both of the two
last-addressed embodiments, hardening the material is accomplished
by at least one of heating and irradiating with light, in
particular with ultraviolet light. In particular, the hardening can
be curing.
[0055] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the spacer wafer is made of a
material which substantially attenuates or blocks light generally
detectable by the detecting members. Using for the spacer wafer a
material which is substantially non-transparent for light
detectable by the detecting members can make it possible to shield
the detecting members from undesired light such as stray light from
outside the module or, if emission members are provided (see
below), to prevent cross-talk from the emission members to the
detecting members.
[0056] In some embodiments, referring to the before-addressed
embodiment, a multitude of emission members for emitting light
generally detectable by the detecting members is arranged on the
substrate wafer, in particular, wherein the emission members are
arranged such that a multitude of neighboring emission members and
detecting members are present on the substrate wafer. In some
cases, each of the emission members is associated with one of the
detecting members.
[0057] With respect to the emission members and their emitted light
spectrum, it is to be noted that the emission of light generally
detectable by the detecting members does not mean that the emitted
light necessarily has to cover the full wavelength range of light
generally detectable by the detecting members, or that an
(additional) emission of light not generally detectable by the
detecting members would be excluded. For example, a transparency
for a portion of the light generally detectable by the detecting
members is sufficient. In some cases, an emission of light a
portion of which falls into the wavelength range generally
detectable by the detecting members is sufficient.
[0058] In some embodiments, referring to one or both of the two
last-addressed embodiments, the emission members are placed on the
substrate wafer for emitting the light in a direction generally
perpendicular to the extension of the substrate. This way,
vertically propagating light is emitted which may, for example, run
through one of the transparent portions.
[0059] In some embodiments, referring to one or more of the
embodiments comprising the emission members, each of the passive
optical components or each of a portion of the passive optical
components is associated with one of the emission members each.
[0060] In some embodiments, referring to one or more of the
embodiments comprising the emission members and lens members, each
of the lens members or each of a portion of the lens members is
associated with one of the emission members each.
[0061] In some embodiments, referring to one or more of the
embodiments comprising the emission members, the multitude of
passive optical components comprises one plurality of passive
optical components associated with one of the emission members each
and another plurality of passive optical components associated with
one of the detecting members each. This way, modules comprising an
emission member arranged below an associated passive optical
component (e.g., lens member) and a detecting member arranged below
an associated passive optical component (e.g., lens member; these
lens members being not identical with the before-mentioned ones)
can be manufactured.
[0062] In this disclosure, "below" refers to a generally vertical
direction (with respect to the wafer extension).
[0063] In some embodiments, referring to one or more of the
embodiments comprising the emission members, the spacer wafer is
structured and arranged such that it reduces optical cross-talk
between the emission members and the detecting members. This can
allow reducetion of optical cross-talk in the sense of reducing or
nullifying the amount of light emitted by the emission member and
detected by the detecting member which has reached the detecting
member via an undesired optical path, e.g., having been scattered
(in an undesired way) within the opto-electronic module or having
reached the detecting member without having left the
opto-electronic module. It can allow substantial attenuatation or
blocking of light emitted by the emission member which did not pass
(two times) through the optics wafer.
[0064] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises the step
of
[0065] h) obtaining the spacer wafer by means of a replication
process.
[0066] This can make the manufacture of the modules particularly
efficient. For example, the replication process can comprises an
embossing step. As a material for the spacer wafer, a polymer-based
material such as an epoxy resin, for example, a curable material,
can be a suitable choice.
[0067] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the material of which the
optics wafer is substantially made in the blocking portion is a
hardened hardenable material (in particular a cured curable
material), e.g., a polymer-based material such as an epoxy
resin.
[0068] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the portion of the optics
wafer in the blocking portion is obtained using a replication
process.
[0069] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the opto-electronic modules
are proximity sensors.
[0070] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises the step
of
[0071] e) providing the substrate wafer with solder balls on that
side of the substrate sensor which is opposed to that side of the
substrate member on which the detecting members are arranged.
[0072] It is also possible to provide a substrate wafer having
contact pads not provided with solder balls.
[0073] This way, the manufactured modules can be readily used in
the manufacture of electronic devices, e.g., it can be used as a
surface mount device.
[0074] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises the step
of
[0075] f) separating the wafer stack into a multitude of separate
modules each comprising [0076] a portion of the substrate wafer;
[0077] at least one of the detecting members; [0078] a portion of
the spacer wafer; [0079] at least one of the transparent portions;
and [0080] a portion of the blocking portion.
[0081] This way, separate opto-electronic modules are obtained in a
very efficient way. The separating (e.g., dicing) can be
accomplished by, e.g., by means of a mechanical tool such as a
wafer saw or a punch cutter, or by means of a laser.
[0082] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the method comprises the step
of
[0083] g) providing a baffle wafer arranged next to the optics
wafer on that side of the optics wafer which is opposed to that
side of the optics wafer on which the spacer wafer is arranged, the
baffle wafer comprising a multitude of transparent regions;
wherein step d) is replaced by the step of
[0084] d') preparing a wafer stack in which the spacer wafer is
arranged between the substrate wafer and the optics wafer such that
the detecting members are arranged between the substrate wafer and
the optics wafer, and wherein the optics wafer is arranged between
the baffle wafer and the spacer wafer.
[0085] By means of the baffle wafer, it is possible to limit an
angular range within which light incident on the baffle layer can
enter the modules and/or reach at least a portion of the multitude
of detection members.
[0086] More particularly, the baffle wafer is a wafer referred to
as baffle wafer.
[0087] In some cases, each of the transparent regions or each of a
portion of the transparent regions is associated with at least one
of the detecting members; and/or, if the emission members are
provided, each of the transparent regions or each of a portion of
the transparent regions is associated with at least one of the
emission members.
[0088] The transparent regions can, e.g., be formed by holes
through the baffle wafer and/or by material transparent for light
generally detectable by the detecting members.
[0089] In some embodiments, referring to the last-addressed
embodiment, the baffle wafer is partially or even substantially
made of a resilient or of an elastically or plastically deformable
material. E.g., a foam or a foam-like material can be used.
[0090] In some embodiments, which may be combined with one or both
last-addressed embodiments, the material of which the baffle wafer
is substantially made is a hardened hardenable material (in
particular a cured curable material), e.g., a polymer-based
material such as an epoxy resin. Note that it is possible to
provide that in the hardened or cured state, the material is
resilient.
[0091] In some embodiments, which may be combined with one or more
of the three last-addressed embodiments, the baffle wafer is
obtained using a replication process.
[0092] In some embodiments, which may be combined with one or more
of the four last-addressed embodiments, the method comprises
providing a wafer which is a combination of the baffle wafer and
the optics wafer. Such a wafer can be referred to as "combined
optics wafer".
[0093] In some embodiments, which may be combined with one or more
of the five last-addressed embodiments, the method comprises the
step of manufacturing the blocking portion and the baffle wafer as
a unitary part. This may, for example, be accomplished using
replication.
[0094] Combining wafers (and, correspondingly, the respective
members) can be accomplished with relatively few manufacturing
steps and, in particular, with relatively few alignment steps. This
may simplify manufacture and/or result in modules of higher
precision.
[0095] In some embodiments, which may be combined with one or more
of the before-addressed embodiments, the substrate wafer
substantially is a printed circuit board assembly, for example, a
printed circuit board on which at least one active optical
component is mounted. This way, the well-known techniques of
printed circuit board fabrication can be used for the manufacture
of the substrate wafer. A printed circuit board arrangement (PCBA)
comprises a printed circuit board (PCB). It can be a printed
circuit board or a printed circuit board with one or more
electrical or electronic components mounted thereon, wherein the
one or more components may be, for example, active optical
components such as the detecting members and/or the emission
members.
[0096] Contact areas for electrically contacting the detecting
members and, if provided, the emission members, and contact areas
electrically contacting the modules from the outside and electrical
connections (vertically) across the substrate wafer can thus be
readily provided.
[0097] According to another (second) aspect of the invention, an
opto-electronic module comprises: [0098] a substrate; [0099] an
optics member arranged generally parallel to the substrate; [0100]
a detecting member arranged between the substrate and the optics
member, mounted on the substrate, for detecting light having passed
through the optics member; [0101] a separation member arranged
between the substrate and the optics member; wherein the optics
member comprises at least one transparent portion transparent for
light generally detectable by the detecting member and at least one
blocking portion for substantially attenuating or blocking incident
light generally detectable by the detecting member.
[0102] Such a module can provide a particularly good
manufacturability and a particularly accurate and/or simple
alignment of constituents, and it can be designed to be very
small.
[0103] The detection member may, generally, be comprised in the
substrate or be not comprised in the substrate. In case the
detection member is comprised in the substrate, one could rather
and more clearly say that the detection member is arranged "on a
side of the substrate facing the optics member," instead of
arranged "between the substrate and the optics member."
[0104] In some implementations, opto-electronic modules have
features of the corresponding methods, and likewise, methods have
features of the corresponding opto-electronic modules. Some
specific examples of the modules are described below.
[0105] The advantages of the modules basically correspond to the
advantages of corresponding methods and vice-versa.
[0106] In some embodiments of the module, the separation member is
arranged beside the detecting member.
[0107] In some embodiments of the module, which may be combined
with the before-addressed embodiment, the at least one blocking
portion is made of a material which substantially attenuates or
blocks light generally detectable by the detecting member. For
example, the material can be a thermally cured material.
[0108] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate is a generally planar substrate.
[0109] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate is a generally plate-like substrate.
[0110] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
optics member is a generally planar optics member (at least when
disregarding possibly existing protruding lens member portions or
protruding portions of other passive optical components).
[0111] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
optics member is a generally plate-like optics member.
[0112] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member is a generally planar separation member.
[0113] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member is a generally plate-like separation member.
[0114] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member has one or more openings. For example, the
detecting member can be arranged in one of these openings.
[0115] In some embodiments of the module which may be combined with
one or more of the before-addressed module embodiments, the optics
member and the separation member are combined in one member. In
particular, the at least one blocking portion and the separation
member are manufactured as a unitary part, e.g., using
replication.
[0116] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
detecting member is a packaged electrical component, e.g., an SMT
device.
[0117] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, except
for the last-addressed embodiment, the detecting member is an
unpackaged electrical component, e.g., a flip chip or a chip
attached to the substrate by wire-bonding.
[0118] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
transparent portion comprising at least one passive optical
component, or, more particularly, at least one lens member.
[0119] In some embodiments, referring to the before-addressed
embodiment, the at least one passive optical component (or the at
least one lens member) comprises at least one optical structure (or
at least one lens element), wherein the at least one optical
structur (or the at least one lens element) is at least one of made
of a hardened hardenable material and obtained using a replication
process. For exampe, the hardened hardenable material can be
hardened by at least one of heating and irradiating with light, in
particular ultraviolet light. More particularly, the hardening can
be a curing. The replication process may comprise an embossing
step.
[0120] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate and the optics member are fixed to each other via the
separation member.
[0121] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member extends substantially from the substrate to the
optics member.
[0122] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member is glued to the optics member and to the
substrate, e.g., by means of a thermally curing glue, e.g., a
suitable epoxy resin.
[0123] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate, the optics member and the separating member are of
generally block- or plate-like shape, at least the separating
member having at least one hole, in particular wherein the hole
extends through the separating member. This way, it is possible
that a particularly good manufacturability is achieved.
[0124] In some embodiments of the module, referring to the
before-addressed embodiment, the detecting member is arranged
within the hole.
[0125] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments,
wherein the substrate, the optics member and the separating member
have rectangularly arranged outer surfaces.
[0126] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments,
lateral dimensions of [0127] the substrate; [0128] the optics
member; and [0129] the separation member; are substantially
identical, in particular wherein the lateral dimensions of the
module are substantially identical therewith.
[0130] The term lateral dimensions refers to dimensions measured
substantially perpendicular to the direction in which the substrate
and the separation member and the optics member are subsequently
arranged. With the lateral outer dimensions of substrate, optics
member and separation member being substantially identical, the
manufacturability of the module is greatly enhanced.
[0131] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
module comprises an emission member for emitting light generally
detectable by the detecting member.
[0132] In some embodiments, referring to the before-addressed
embodiment, at least a portion of the separation member is arranged
between the emission member and the detecting member for reducing
optical cross-talk between the emission member and the detecting
member.
[0133] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
detecting member is encircled by the separating member.
[0134] In some embodiments, referring to one or more of the
before-addressed module embodiments comprising an emission member,
the emission member is encircled by the separating member.
[0135] For example, a portion of side walls (circumferential side
walls) of the module can be formed by the separation member.
[0136] In some embodiments, referring to one or more of the
before-addressed embodiments comprising an emission member, the
optics member comprises at least a first and a second lens members
comprising at least one lens element each. In particular, it can be
provided that the first and second lens members form a first and a
second transparent portion, respectively, of the optics member, and
more particularly, wherein the first and second lens members are
surrounded by the blocking portion.
[0137] In some embodiments, referring to the last-addressed
embodiment, viewed in a direction generally perpendicular to the
substrate (vertical direction), the emission member and the first
lens member are arranged one after the other, and the detecting
member and the second lens member are arranged one after the other.
Such a module can be very small and highly functional.
[0138] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
emission member is a packaged electrical component, e.g., an SMT
device.
[0139] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments
comprising an emission member, except for the last-addressed
embodiment, the emission member is an unpackaged electrical
component, e.g., a flip chip or a chip attached to the substrate by
wire-bonding.
[0140] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments
comprising an emission member, the emission member, the optics
member and the detecting member are structured and arranged such,
that when light emitted from the emission member having passed the
at least one transparent portion and having been reflected by a
surface located outside the module and having passed the at least
one transparent portion again is detected by the detecting member,
an amount of the so-detected light depends on a distance of the
surface to the optics member.
[0141] Therein, the surface located outside the module can be
located near the optics member, e.g., in some applications, in a
distance below 1 m, more particularly below 20 cm or even below 8
cm.
[0142] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member is made of a material which substantially
attenuates or blocks light generally detectable by the detecting
member. This can be particularly helpful when the separation member
is provided for substantially attenuating or blocking light
generally detectable by the detecting member, but incident from a
side of the separation member opposed to a side of the separation
member facing the detecting member, from being detected by the
detecting member.
[0143] In some cases, the separation member is not a portion of the
substrate and not a portion of the optics member. The separation
member can be a unitary part
[0144] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
separation member is at least one of made of a hardened hardenable
material and obtained using a replication process. More
particularly, the hardening can be a curing. In particular, the
hardened hardenable material (or cured curable) can be hardened
(cured) by application of heat.
[0145] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the at
least one transparent portion is substantially made of a
polymer-based material, e.g., of an epoxy resin, or in particular
of a cured curable material.
[0146] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the at
least one blocking portion is substantially made of a polymer-based
material, e.g., of an epoxy resin.
[0147] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate provides at least one electrical connection from the
detection member across the substrate. This is an elegant way to
electrically contact (from the outside) active optical components
located within the module.
[0148] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
substrate is a printed circuit board assembly. Since this printed
circuit board assembly is a constituent of a package, namely of the
module, it can also be referred to as an interposer with at least
one active optical component mounted thereon. The printed circuit
board (PCB) material may, e.g., be a rigid or a flexible PCB
material, a fiber-reinforced or not fiber-reinforced material, it
may be epoxy-based such as FR4 or polyimide. Active optical
components may be mounted on the PCB, e.g., by means of wire
bonding or soldering. The same applies also to the PCB of the PCB
assembly possibly constituting the substrate wafer.
[0149] In some implementations, at least one of the detecting
member and the emission member is electrically connected to the
substrate member, wherein this can be accomplished, e.g., by
soldering, by surface mount technology (SMT) or by flip-chip
technology or by wire-bonding.
[0150] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments, the
module comprises a baffle member arranged next to the optics member
on that side of the optics member which is opposed to that side of
the optics member on which the separation member is arranged. The
baffle member can be structured and arranged for protection from
undesired light, in particular for protection of the detecting
member from undesired light, and/or for functioning as an
aperture.
[0151] In some embodiments of the module, referring to the
last-addressed module embodiment, the baffle member is partially or
even substantially made of a resilient or of an elastically or
plastically deformable material. This can be helpful, e.g., when
mounting the module. For example, when a module is arranged within
a housing in mechanical contact to a window of the housing,
mounting tolerances can be absorbed by a resilient baffle member,
e.g., making the distance of a printed circuit board on which the
module is mounted to the window less critical, the resilient baffle
member accounting for variations in that distance by readily
deforming and adjusting itself.
[0152] In some embodiments of the module, to be combined with one
or both of the last-addressed module embodiments, the baffle member
and the optics member are combined in one member; in particular,
the at least one blocking portion and the spacer member are
manufactured as a unitary part, e.g., using replication.
[0153] In some embodiments of the module, which may be combined
with one or more of the before-addressed module embodiments,
wherein the module is a proximity sensor.
[0154] An appliance can comprise a multitude of the modules. For
example, the appliance can comprise a substrate wafer, an optics
wafer, a spacer wafer, wherein the multitude of substrates is
comprised in the substrate wafer, the multitude of optics members
is comprised in the optics wafer, the multitude of separation
members is comprised in the spacer wafer. The appliance can be
considered a wafer stack. All the wafers can be generally planar
and generally disk- or plate-shaped (in case of the optics wafer,
at least when disregarding possibly existing protruding lens member
portions (or more generally protruding portions of passive optical
components)).
[0155] An electronic device can comprise a printed circuit board
and a module mounted on the printed circuit board. For example, the
device can be a hand-held communication device. The device could
also can be a photographic device, such as a photo camera.
[0156] In another aspect (second aspect), of the invention, a
method for manufacturing opto-electronic modules comprises:
[0157] a') providing a substrate wafer on which a multitude of
detecting members are arranged;
[0158] b') providing a spacer wafer;
[0159] c') providing an optics wafer; and
[0160] d') preparing a wafer stack in which the spacer wafer is
arranged between the substrate wafer and the optics wafer such that
the detecting members are arranged between the substrate wafer and
the optics wafer,
wherein the substrate wafer substantially is a printed circuit
board assembly.
[0161] Particular embodiments of this method are readily
conceivable when combining this method with the methods described
above, including or excluding the feature that the optics wafer
comprises a multitude of transparent portions and at least one
blocking portion.
[0162] Similarly, in this aspect of the invention, the following
opto-electronic modules, appliances and electronic devices are
comprised:
[0163] An opto-electronic module comprising [0164] a substrate
substantially being a printed circuit board assembly; [0165] an
optics member arranged generally parallel to the substrate; [0166]
a detecting member arranged between the substrate and the optics
member, mounted on the substrate, for detecting light having passed
through the optics member; and [0167] a separation member arranged
between the substrate and the optics member.
[0168] An appliance comprising a multitude of modules according to
the foregoing aspect.
[0169] An electronic device comprising a printed circuit board and
a module according to the foregoing aspect mounted on the printed
circuit board.
[0170] Particular embodiments of these opto-electronic modules and
appliances and electronic devices, respectively, according to the
foregoing aspect are readily conceivable when combining these with
the opto-electronic modules and appliances and electronic devices,
respectively, described above, including or excluding the feature
that the optics member comprises at least one transparent portion
and at least one blocking portion.
[0171] It is to be noted that it is possible that a wafer
("combined optics wafer") is provided which is a combination of the
described optics wafer and the described spacer wafer. Accordingly,
then, the spacer wafer is optional, its properties and functions
are fulfilled by an optics wafer which is structured and configured
accordingly. This can be accomplished, e.g., by manufacturing as a
unitary part: what is described above as spacer wafer and what is
described above as at least one blocking portion. Analogously, a
"combined optics wafer" can be provided which can be understood as
a combination of the described optics wafer and the described
baffle wafer. And, it is also possible to provide that the
"combined optics wafer" can be understood as a combination of the
described optics wafer and the described spacer wafer and the
described baffle wafer.
[0172] Correspondingly, it is possible that a member is provided
which is a combination of the described optics member and the
described separation member. Accordingly, then, the separation
member is optional, its properties and functions are fulfilled by
an optics member which is structured and configured accordingly.
This can be accomplished, e.g., by manufacturing as a unitary part:
what is described above as separation member and what is described
above as at least one blocking portion. An alternative or
additional combination with the baffle member is, of course, also
possible.
[0173] In other words, it applies to any of the disclosed
embodiments that the spacer wafer and/or the baffle wafer (if at
all present) may be comprised in the optics wafer or may be
separated therefrom; and that the separation member and/or the
baffle member (if at all present) may be comprised in the optics
member or may be separated therefrom.
[0174] In accordance with another aspect, a method for
manufacturing opto-electronic modules, the method comprises:
[0175] A) providing a substrate wafer on which a multitude of
detecting members are arranged;
[0176] C) providing an optics wafer, the optics wafer comprising a
multitude of transparent portions transparent for light generally
detectable by the detecting members and at least one blocking
portion for substantially attenuating or blocking incident light
generally detectable by the detecting members; and
[0177] D) preparing a wafer stack comprising the substrate wafer
and the optics wafer.
[0178] Likewise, an opto-electronic module can comprise: [0179] a
substrate; [0180] an optics member arranged generally parallel to
the substrate; and [0181] a detecting member arranged between the
substrate and the optics member, mounted on the substrate, for
detecting light having passed through the optics member; wherein
the optics member comprises at least one transparent portion
transparent for light generally detectable by the detecting member
and at least one blocking portion for substantially attenuating or
blocking incident light generally detectable by the detecting
member.
[0182] Additional aspects, features and advantages of the invention
will be readily apparent from the detailed description, the
accompanying drawings and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0183] Below, examples of the invention are described in more
detail with reference to the drawings. The figures show
schematically:
[0184] FIG. 1 a cross-sectional view of an opto-electronic
module;
[0185] FIG. 2 various cross-sectional views of constituents of the
module of FIG. 1;
[0186] FIG. 3 a cross-sectional view of wafers for forming a wafer
stack for manufacturing a multitude of modules of FIG. 1;
[0187] FIG. 4 a cross-sectional view of a wafer stack for
manufacturing a multitude of modules of FIG. 1;
[0188] FIG. 5 a cross-sectional view of a semi-finished part having
a structured surface;
[0189] FIG. 6 a cross-sectional view of an opto-electronic module
comprising a combined optics member comprising a separation member
and a baffle member.
[0190] The reference symbols used in the figures and their meaning
are summarized in the list of reference symbols. The described
embodiments are intended as examples.
DETAILED DESCRIPTION
[0191] FIG. 1 shows a schematic cross-sectional view of an
opto-electronic module 1. The illustrated cross-section is a
vertical cross-section. FIG. 2 shows various lateral schematic
cross-sectional views of constituents of the module of FIG. 1,
wherein the approximate positions of these lateral cross-sections
are indicated in FIG. 1 by s1 to s5 and dashed lines. For s4 and
s5, the direction of view is indicated by arrows.
[0192] Module 1 comprises several constituents (P, S, O, B) stacked
upon each other in a direction through which the term "vertical" is
defined; it corresponds to the z direction (cf. FIG. 1). Directions
in the x-y plane (cf. FIG. 2) perpendicular to the vertical (z)
direction are referred to as "lateral".
[0193] Module 1 comprises a substrate P, a separation member S, an
optics member O and a baffle member B stacked upon each other.
Substrate P is, e.g., a printed circuit board assembly. The printed
circuit board (PCB) of this PCB assembly can more specifically also
be referred to as an interposer. On the PCB, an emission member E
for emitting light, in particular infrared light (more particularly
near-infrared light), can be mounted, e.g., a light-emitting diode;
and a detecting member D can be mounted thereon, for detecting
light, in particular infrared light (more particularly
near-infrared light, e.g., a photo diode. Electrical contacts of
emission member E and detecting member D are electrically connected
to the outside of module 1, where solder balls 7 are attached.
Instead of providing solder balls 7, it would also be possible to
provide contact pads on the PCB which are not (or at a later time)
provided with solder balls.
[0194] This way, module 1 can be mounted on a printed circuit board
9, e.g., in surface mount technology (SMT), next to other
electronic components (not shown). Printed circuit board 9 may be a
constituent of an electronic device 10 such as a hand-held
communication device. In particular, device 10 can be a smart
phone. Module 1 is particularly suitable for such an application
because it can be manufactured having a particularly small
size.
[0195] Separation member S has two openings 4, emission member E
arranged in one of them and detecting member D being arranged in
the other. This way, emission member E and detecting member D are
laterally encircled by separating member S.
[0196] Separation member S may fulfill several tasks. It can ensure
a well-defined distance between substrate P and optics member O
(through its vertical extension) which helps to achieve
well-defined light paths from emitting member E through optics
member O and from the outside of module 1 through optics member O
onto detecting member D. Separation member S can also provide
protection of detecting member D from light that is not supposed to
be detected by detection member D, by being substantially
non-transparent to light generally detectable by detecting member D
and by forming a portion of the outside walls of module 1. And,
separation member S can also provide protection of detecting member
D from light emitted by emitting member E which should not reach
detecting member D, so as to reduce optical cross-talk between
emission member E and detecting member E, by being substantially
non-transparent to light generally detectable by detecting member D
and by forming a wall between emission member E and detecting
member D. Light reflected inside module 1 and stray light
originating from emission member E can be kept from reaching
detecting member D this way. Separating member S can be made of a
polymer material, in particular of a hardenable or more
specifically curable polymer material, e.g., of an epoxy resin.
[0197] Optics member O comprises a blocking portion b and two
transparent portions t, one for allowing light emitted by emission
member E to leave module 1, and another one for allowing light to
enter module 1 from the outside of module 1 and reach detecting
member D.
[0198] Blocking portion b is substantially non-transparent for
light generally detectable by detecting member D, e.g., by being
made of a suitable (polymer) material. Transparent portions t
comprise a passive optical component L or, more particularly and as
an example, a lens member L each, for light guidance. Lens members
L may, e.g., comprise, as shown in FIG. 1, two lens elements 5 in
close contact to a transparent element 6. Transparent elements 6
can have the same vertical dimension as optics member O where it
forms blocking portion b, such that optics member O where it forms
blocking portion b together with transparent elements 6 describes a
(close-to-perfect) solid plate shape. Lens elements 5 redirect
light by refraction (cf. FIG. 1) and/or by diffraction. E.g., they
may all be of generally convex shape (as shown in FIG. 1), but one
or more of lens elements 5 may be differently shaped, e.g.,
generally or partially concave.
[0199] Baffle member B allows to shield undesired light, in
particular light leaving module 1 or incident to module 1 in an
desired angle. For example, baffle member B can have two separate
transparent regions 3 which may be embodied as openings or by means
of transparent material. Baffle member B can, outside the
transparent regions 3, be made of a material substantially
attenuating or blocking light generally detectable by the detecting
members, or it could be provided with a coating having such a
property, wherein the latter can be more complex to manufacture.
The shape of baffle member B or more precisely of the transparent
regions 3, can be different from what is shown in FIGS. 1 and 2,
e.g., describe cone-like shapes or describe a truncated
pyramid.
[0200] The lateral shape not only of the transparent regions 3, but
also of the transparent portions t and of the openings 4 do not
have to be circular, but may have other appearances, e.g.,
polygonal or rectangular with rounded corners.
[0201] Module 1 is an opto-electronic component, more precisely a
packaged opto-electronic component. The vertical side walls of
module 1 are formed by items P, S, O and B. A bottom wall is formed
by substrate P, and a top wall by baffle member B or by baffle
member B together with optics member O.
[0202] As is well visible in FIG. 2, the four items P, S, O, B,
which can for the reasons above also be referred to as housing
components, all have substantially the same lateral shape and
lateral dimensions. This is related to a possible and very
efficient way of manufacturing such modules 1 which is described in
more detail below referring to FIGS. 3 and 4. These housing
components P, S, O, and B are all of generally block- or plate-like
shape or more generally of generally rectangular parallelepiped
shape, possibly having holes or openings (such as baffle member B
and separation member S do) or projections (such as optics member O
does).
[0203] The module 1 shown in FIG. 1 can be a proximity sensor. Such
a module 1 would allow to detect whether or not an object is
located within a predefined distance to the module, e.g., as judged
from a photocurrent outputted by detecting member D, while emission
member E would be emitting light, possibly in form of light pulses.
For example, emission member E, optics member O and detecting
member D could be arranged such, that a surface capable of
reflecting light located within a predefined distance or distance
range of optics member O could enable a detection by detecting
member D of a sufficiently high intensity of light emitted by
emission member E and reflected by the surface, whereas light
emitted by emission member E and reflected by such a surface
located farther away from optics member O and outside the
predefined distance, respectively, would not cause a detection of
high-enough light intensity by detecting member D.
[0204] It would also be possible to create a module which comprises
(as electronic components) only a detecting member D and no
emission member E. In that case, the module could be embodied
substantially as the right half of the module 1 shown in FIGS. 1
and 2.
[0205] Furthermore, it is possible to provide modules which are
designed according to the same principles as discussed above, but
comprising, in addition to detecting member D, one or more
additional electronic components such as additional light
detectors, or one or more integrated circuits, or two or more light
sources.
[0206] The active electronic components comprised in a module (such
as emission member E and detecting member D in the example of FIG.
1) can be packaged or unpackaged electronic components. For
contacting substrate P, technologies such as wire-bonding or flip
chip technology or any other known surface mount technologies may
be used, or even conventional through-hole technology.
[0207] FIG. 3 shows a schematical cross-sectional view of wafers
for forming a wafer stack for manufacturing a multitude of modules
as shown in FIG. 1. It is possible to manufacture such modules 1
(practically) completely on wafer-scale, of course with a
subsequent separation step. Although FIGS. 3 and 4 only show
provisions for three modules 1, there can be in one wafer stack
provisions for at least 10, rather at least 30 or even more than 50
modules in each lateral direction. Example dimensions of each of
the wafers are: laterally at least 5 cm or 10 cm, and up to 30 cm
or 40 cm or even 50 cm; and vertically (measured with no components
arranged on substrate wafer PW) at least 0.2 mm or 0.4 mm or even 1
mm, and up to 6 mm or 10 mm or even 20 mm.
[0208] Four wafers are sufficient for manufacturing a multitude of
modules as shown in FIG. 1: A substrate wafer PW, a spacer wafer
SW, an optics wafer OW and a baffle wafer BW. Each wafer comprises
a multitude of the corresponding members comprised in the
corresponding module 1 (cf. FIGS. 1 and 2), arranged, for example,
on a rectangular lattice, e.g., with a little distance from each
other for a wafer separation step.
[0209] Substrate wafer PW can be a PCB assembly comprising a PCB of
standard PCB materials, provided with solder balls 7 on the one
side and with active optical components (E and D) soldered to the
other side. The latter can be placed on substrate wafer PW by
pick-and-place using standard pick-and-place machines.
[0210] In order to provide maximum protection from detecting
undesired light, all wafers PW, SW, OW, BW can substantially be
made of a material substantially non-transparent for light
detectable by detecting members D, of course except for transparent
areas such as transparent portions t and transparent regions 3.
[0211] Wafers SW and BW and possibly also all or a portion of wafer
OW can be produced by replication. In an exemplary replication
process, a structured surface is embossed into a liquid, viscous or
plastically deformable material, then the material is hardened,
e.g., by curing using ultraviolet radiation or heating, and then
the structured surface is removed. Thus, a replica (which in this
case is an negative replica) of the structured surface is obtained.
Suitable materials for replication are, e.g., hardenable (more
particularly curable) polymer materials or other replication
materials, i.e. materials which are transformable in a hardening
step (more particularly in a curing step) from a liquid, viscous or
plastically deformable state into a solid state. Replication is a
known technique, cf., e.g., WO 2005/083789 A2 for more details
about this.
[0212] In case of optics wafer OW, replication or molding may be
used for obtaining the non-transparent portions (blocking portions
b). It would also be possible to provide holes, where transparent
portions t are supposed to be, by drilling or by etching.
[0213] Subsequently, a so-obtained precursor wafer is provided with
lens members L, so as to yield optics wafer OW. This may be
accomplished by means of replication, e.g., forming lens members L
as a unitary parts, e.g., as described in US 2011/0043923 A1. The
lens members L can, however, also be manufactured starting from a
semi-finished part being a wafer comprising transparent elements 6
within holes by which transparent portions t are defined. This can
be particularly useful when the lens members L each describe at
least one apex, and those apices are located outside a vertical
cross-section of the optics wafer OW. Such a semi-finished part can
be (as in the example shown in the figures) a flat disk-like wafer
having no holes penetrating the wafer in the transparent portions t
and having virtually no or only shallow surface corrugations, such
surface corrugations being, for example, concave, i.e. not
extending beyond the wafer surface as described by the blocking
portions b.
[0214] A semi-finished part like that can be obtained starting from
a flat precursor wafer (made, for example, of one material) having
holes or openings where the transparent portions are supposed to be
and then filling the holes with transparent material, e.g., using a
dispensing process, and either filling the holes in the precursor
wafer one-by-one, e.g., using a dispenser such as used for
underfilling processes in flip-chip technology or the like, or by
filling several holes at once, e.g., using a squeegee process (e.g.
as known from screen printing) or a dispenser with several hollow
needles outputting material. During the dispensing, the wafer can
be placed on a flat support plate, e.g., made of a silicone. Care
has to be taken order to prevent the formation of air bubbles or
cavities in the dispensed material, since this would degrade the
optical properties of the lens members L to be produced. E.g., one
can carry out the dispensing in such a way that wetting of the
wafer material starts at an edge formed by the wafer and an
underlying support plate (or in a place close to such an edge),
e.g., by suitably guiding a hollow needle outputting the material
close to such an edge. Subsequently, the dispensed material is
cured, e.g., by heat or UV radiation, so as to obtain hardened
transparent material.
[0215] Convex meniscuses possibly formed this way can be flattened
by polishing, so as to obtain a transparent element 6 having
parallel surfaces adjusted to the wafer thickness. Then, by means
of replication, lens elements 5 are applied, for example, to both
sides (top and button side) of wafer OW. In case of concave
meniscuses of the transparent elements, the replication can take
place on these, wherein the amount of applied replication material
might have to be adjusted accordingly.
[0216] As has already been mentioned, it is generally possible to
provide that the spacer wafer SW and/or the baffle wafer BW are
obsolete in the sense that a particular kind of optics wafer is
provided. Namely an optics wafer ("combined optics wafer") which
incorporates the features and functionalities of the spacer wafer
SW and/or the baffle wafer BW. Producing such a "combined optics
wafer" may be accomplished using a particular precursor wafer and,
manufactured based thereon, a particular semi-finished part. Such a
precursor wafer and semi-finished part, respectively, has at least
one structured surface, having, for example, protrusions extending
vertically beyond at least one of the two surfaces of transparent
elements to be provided in precursor wafer and present in the
semi-finished part, respectively.
[0217] In FIG. 5, an example of a semi-finished part ow' with one
structured surface is schematically illustrated. This example for a
semi-finished part ow' can be used for manufacturing an optics
wafer ("combined optics wafer") and can be understood as a
combination of an optics wafer OW and a spacer wafer SW.
[0218] It is readily deduced from FIG. 5, what a semi-finished part
could look like when it would be used for manufacturing a module
shown in FIG. 1. Looking upon wafers OW and SW (or wafers OW and
BW, or wafers OW and SW and BW) in FIG. 4 as one single part it can
be readily visualized what a corresponding optics wafer ("combined
optics wafer") for manufacturing a module according to FIG. 1 and
also a corresponding semi-finished part would look like. FIG. 6
schematically illustrates, a cross-sectional view of an
opto-electronic module comprising a combined optics member. This
opto-electronic module corresponds to the one of FIG. 1, only
neither separation member S nor baffle member B are separate from
optics member O. They are both comprised in optics member O.
Separation member S and baffle member B can both be manufactured
together, in a single process, with blocking portion b of optics
member O.
[0219] In order to form a wafer stack 2, the wafers are aligned and
bonded together, e.g., by gluing, e.g., using a heat-curable epoxy
resin. Each active optical component (such as detecting members D
and emission members E on the substrate wafer PW) should be
sufficiently accurately allocated with a corresponding passive
optical component (such as lens members L of the optics wafer
OW).
[0220] FIG. 4 shows a cross-sectional view of a so-obtained wafer
stack 2 for manufacturing a multitude of modules 1 as shown in FIG.
1. The thin dashed rectangles indicate where separation takes
place, e.g., by means of using a dicing saw.
[0221] The fact that most alignment steps are carried out on wafer
level makes it possible to achieve a good alignment (in particular
of members D and E with respect to members L) in a rather simple
and very fast way. The overall manufacturing process is very fast
and precise. Due to the wafer-scale manufacturing, only a very
small number of production steps is required for manufacturing a
multitude of modules 1.
[0222] Other implementations are within the scope of the
claims.
LIST OF REFERENCE SYMBOLS
[0223] 1 opto-electronic module, proximity sensor
[0224] 2 wafer stack
[0225] 3 transparent region
[0226] 4 opening
[0227] 5 optical structure, lens element
[0228] 6 transparent element
[0229] 7 solder ball
[0230] 9 printed circuit board
[0231] 10 electronic device, smart phone
[0232] b blocking portion, non-transparent portion
[0233] B baffle member
[0234] BW baffle wafer
[0235] D detecting member, detector, photo diode
[0236] E emission member, light emitter, light-emitting diode
[0237] L passive optical component, lens member
[0238] O optics member
[0239] ow' semi-finished part
[0240] OW optics wafer
[0241] P substrate
[0242] PW substrate wafer
[0243] s1,s2, . . . refers to a sectional view
[0244] S separation member
[0245] SW spacer wafer
[0246] t transparent portion
* * * * *