U.S. patent application number 13/408899 was filed with the patent office on 2012-10-11 for system and method for electrochemical processing of non-flat samples.
This patent application is currently assigned to Katholieke Universiteit Leuven. Invention is credited to Frederic Dross, Alex Masolin.
Application Number | 20120255869 13/408899 |
Document ID | / |
Family ID | 42945976 |
Filed Date | 2012-10-11 |
United States Patent
Application |
20120255869 |
Kind Code |
A1 |
Masolin; Alex ; et
al. |
October 11, 2012 |
SYSTEM AND METHOD FOR ELECTROCHEMICAL PROCESSING OF NON-FLAT
SAMPLES
Abstract
A system and method for electrochemically processing non-flat
samples and/or samples that can change shape during the
electrochemical processing is disclosed. In one aspect, a system
includes a sample holder for providing an electrical contact to the
sample during electrochemical processing. The sample holder has a
carrying element and a fixing element for clamping of the sample in
between the fixing element and the carrying element, thus providing
electrical contact to the sample while allowing the sample to
change shape without interrupting the electrical contact.
Inventors: |
Masolin; Alex; (Udine,
IT) ; Dross; Frederic; (Schaarbeek, BE) |
Assignee: |
Katholieke Universiteit
Leuven
Leuven
BE
IMEC
Leuven
BE
|
Family ID: |
42945976 |
Appl. No.: |
13/408899 |
Filed: |
February 29, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/EP2010/060965 |
Jul 28, 2010 |
|
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13408899 |
|
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61238993 |
Sep 1, 2009 |
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Current U.S.
Class: |
205/661 ;
204/297.01; 204/297.1; 205/640 |
Current CPC
Class: |
C25D 17/08 20130101;
C25D 7/00 20130101; H01L 21/67086 20130101; C25F 7/00 20130101;
C25D 17/005 20130101 |
Class at
Publication: |
205/661 ;
204/297.01; 204/297.1; 205/640 |
International
Class: |
C25F 7/00 20060101
C25F007/00 |
Claims
1. A system for electrochemically processing non-flat samples
and/or samples that can change shape during the electrochemical
processing, the system comprising: a sample holder configured to
provide an electrical contact to the sample during electrochemical
processing, wherein the sample holder comprises a grid-shaped
carrying element and a fixing element for clamping the sample in
between the fixing element and the carrying element, thus providing
electrical contact to the sample while allowing the sample to
change shape without interrupting the electrical contact.
2. The system according to claim 1, wherein the carrying element is
bent in at least a first direction.
3. The system according to claim 2, further comprising a pre-formed
platform for, in use, reversing the bending of the carrying
element.
4. The system according to claim 1, wherein the carrying element is
a flexible carrying element clamped in a frame of smaller
dimensions than the dimensions of the carrying element such that
the carrying element can take on either of two stable positions,
each stable position corresponding to a different bending direction
of the carrying element.
5. The system according to claim 4, further comprising a pre-formed
platform for, in use, reversing the bending of the carrying
element.
6. The system according to claim 1, wherein the fixing element is a
linear fixing element.
7. The system according to claim 1, wherein the fixing element
provides a contact area between the fixing element and a sample in
the form of a point or an area with limited dimensions less than
about 10% of the corresponding dimensions of the sample.
8. The system according to claim 7, wherein the contact area
between the fixing element and the sample is a substantially
circular contact area.
9. The system according to claim 1, wherein at least one of the
fixing element and the carrying element is electrically
conductive.
10. The system according to claim 1, further comprising a handler
for handling the sample holder.
11. A method of electrochemically processing non-flat samples
and/or samples that can change shape during processing, the method
comprising: clamping a sample between a grid-shaped carrying
element and a fixing element at at least one point, thus providing
an electrical contact to the sample; and electrochemically
processing the clamped sample, while allowing the electrochemically
processed sample to change shape without interrupting the
electrical contact.
12. The method according to claim 11, wherein allowing the
electrochemically processed sample to change shape comprises
reversing a bending direction of the carrying element carrying the
sample.
13. The method according to claim 11, wherein the carrying element
is bent in at least a first direction.
14. The method according to claim 11, wherein the carrying element
is a flexible carrying element clamped in a frame of smaller
dimensions than the dimensions of the carrying element such that
the carrying element can take on either of two stable positions,
each stable position corresponding to a different bending direction
of the carrying element.
15. The method according to claim 11, wherein the fixing element is
a linear fixing element.
16. The method according to claim 11, wherein the sample is clamped
such that the fixing element provides a contact area between the
fixing element and the sample in the form of a point or an area
with limited dimensions less than about 10% of the corresponding
dimensions of the sample.
17. The method according to claim 16, wherein the contact area
between the fixing element and the sample is a substantially
circular contact area.
18. The method according to claim 11, wherein at least one of the
fixing element and the carrying element is electrically conductive.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of PCT Application No.
PCT/EP2010/060965, filed Jul. 28, 2010, which claims priority under
35 U.S.C. .sctn.119(e) to U.S. provisional patent application
61/238,993 filed on Sep. 1, 2009. Each of the above applications is
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The disclosed technology relates to methods and systems for
electrochemical processing of non-flat samples and/or samples that
may change shape during electrochemical processing, and more in
particular, to methods and systems for holding such samples and for
maintaining a good electrical contact to such samples during
electrochemical processing, e.g. electrochemical etching, plating
or cleaning.
[0004] 2. Description of the Related Technology
[0005] Nowadays' production of photovoltaic cells mainly relies on
silicon. The price of silicon photovoltaic modules is to a large
extent driven by the cost of the silicon material. Furthermore,
with currently industrially achievable surface recombination
velocities, the optimum thickness for achieving the highest
efficiency of a crystalline silicon photovoltaic cell is in the
range of 50 micrometer. For a thickness below a few tens of
micrometer, silicon becomes flexible. Encapsulated in a suitable
and flexible material, it can provide a building block for
applications requiring lightweight, flexible, high efficiency
photovoltaic modules.
[0006] When forming thin silicon wafers by wire sawing from an
ingot, kerf losses consume half of the ingot and the achievable
wafer thickness is limited to 100 micrometer or more. Therefore,
other methods for forming thin silicon wafers for the photovoltaic
industry are needed.
[0007] In US 2007/0249140 a wafering technique is described that
enables the production of very thin (e.g. thinner than 100
micrometer) crystalline silicon wafers. This process is also known
as the SLIM-Cut (stress-induced lift-off method) process. In an
embodiment described in US 2007/0249140, on a thick mother
substrate (e.g. silicon substrate) a layer (e.g. a metallic layer)
with mismatched thermal expansion coefficient with respect to the
mother substrate is provided, e.g. screen printed. The thermal
coefficient of expansion of the metallic layer is much higher, e.g.
more than a factor of 10 higher, than the thermal coefficient of
expansion of silicon. Good bonding between the metallic layer and
the silicon mother substrate can for example be achieved by a
treatment at high temperature in a belt furnace. Upon cooling to
room temperature, the metallic layer and the silicon substrate
undergo a thermal contraction, and the mismatch in coefficient of
thermal expansion between the metallic layer and the silicon
induces a large stress field in the mother substrate. Since the
bonding between the metallic layer and the silicon is sufficiently
strong to withstand this stress load, the stress builds up inside
the silicon material during cooling down. When the stress reaches a
threshold value, the system tends to relax by the initiation and
the propagation of a crack parallel to the main surface of the
mother substrate. After the crack has completely propagated through
the mother substrate, a film is detached and the mother substrate
can be reused. The film detached is composed of the metallic layer
and a thin silicon substrate lifted-off from the mother substrate.
The film is still under stress and exhibits therefore some bending.
In a next step the metal can (at least partially) be removed,
resulting in a (flat) thin silicon film on which e.g. a
photovoltaic cell process can be applied.
[0008] The film detached from the mother substrate may be a
rolled-up stack comprising the thin silicon substrate and at least
one layer of stress inducing material, e.g. metallic layer. As
described in US 2007/0249140, the at least one layer of stress
inducing material may be removed e.g. by chemical etching. By
removing the at least one layer of stress inducing material the
stress is relieved from the thin substrate and the thin substrate
can then become flat and stress-free. For example, in case a stress
inducing stack comprising a layer of Ag paste and a layer of Al
paste is used, removing the Ag/Al layers after release of a film
from the mother substrate may comprise dipping the detached film in
a warm HCl solution and in a mixture of HCl and HNO.sub.3. However,
when using such a chemical etching process, Ag cannot be recovered
easily.
SUMMARY OF CERTAIN INVENTIVE ASPECTS
[0009] Certain inventive aspects relate to a method and a system
for electrochemical processing of non-flat samples and/or samples
that can change shape during processing. The system comprises a
sample holder that provides an electrical contact to the sample
during electrochemical processing, wherein the holder allows the
sample to change shape during electrochemical processing without
interrupting the electrical contact. The system can be used for
processing fragile samples with a low risk of breakage.
[0010] It is an advantage of electrochemical etching that it allows
a better control of the etch rate and has the potential of higher
etch rates as compared to chemical etching, which may lead to
faster processing. In addition, etching solutions may be used that
are less aggressive than in case of chemical etching. In case of
electrochemical etching, metals such as Ag can be recovered more
easily than in case of chemical etching.
[0011] One inventive aspect relates to a system comprising a sample
holder, the sample holder comprising a carrying element and a
fixing element adapted for being pressed against each other,
thereby allowing clamping of a sample, e.g., a substantially
non-flat sample, in between the fixing element and the carrying
element. At least one of the carrying element and the fixing
element is electrically conductive and maintains an electrical
contact to the sample, enabling electrochemical processing.
[0012] The carrying element may be a grid-shaped element. It is an
advantage of a grid-shaped carrying element that during
electrochemical processing it permits a good flow of electrolyte
towards the sample and it allows the release of bubbles that may be
formed during electrochemical processing.
[0013] In case the sample is bent in one direction, the fixing
element may be a linear element, such that the contact area between
the fixing element and the sample is a linear area. It is an
advantage of using a linear fixing element that it allows fixing a
sample bent in one direction on the carrying element and that it
allows the sample to change shape while being fixed on the carrying
element. In case of a sample that is bent in more than one
direction, the fixing element may be such that the contact area
between the fixing element and the sample is a point or a very
small area, e.g., a substantially circular area, wherein the
dimensions in one direction of the contact area are less than about
10% of the dimensions in that direction of the sample.
[0014] The carrying element (e.g. grid) may be such that it can be
bent in a first direction and in a second direction different from
the first direction, wherein bending of the carrying element
towards the second direction causes the carrying element to be
pushed towards the fixing element. The fixing element can be
attached to the carrying element or it can be a separate
element.
[0015] A system according to one inventive aspect can
advantageously be used for holding a sample, e.g. a substantially
non-flat sample or a sample that can change shape during
electrochemical processing, e.g. electrochemical etching, cleaning
or plating.
[0016] Certain inventive aspects are set out in the accompanying
independent and dependent claims. Features from the dependent
claims may be combined with features of the independent claims and
with features of other dependent claims as appropriate and not
merely as explicitly set out in the claims.
[0017] Certain objects and advantages of certain inventive aspects
have been described herein above. Of course, it is to be understood
that not necessarily all such objects or advantages may be achieved
in accordance with any particular embodiment of the invention.
Thus, for example, those skilled in the art will recognize that the
invention may be embodied or carried out in a manner that achieves
or optimizes one advantage or group of advantages as taught herein
without necessarily achieving other objects or advantages as may be
taught or suggested herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a schematic drawing of a system according to an
embodiment of the present invention showing a holder and a sample
during introduction into an electrochemical bath. FIG. 1(a) shows a
cross-section along the y-direction; FIG. 1(b) shows a
cross-section along the x-direction.
[0019] FIG. 2 is a schematic drawing of a system according to an
embodiment of the present invention showing a holder and a sample
during electrochemical processing. FIG. 2(a) shows a cross-section
along the y-direction; FIG. 2(b) shows a cross-section along the
x-direction.
[0020] FIG. 3 is a schematic drawing of a system according to an
embodiment of the present invention showing a holder and a sample
after electrochemical etching. A cross section along the
x-direction is shown.
[0021] FIG. 4 is a schematic drawing of a `vertical` system
according to an alternative embodiment of the present invention
showing a holder and a sample during electrochemical
processing.
[0022] FIG. 5 shows a cross section of a grid with two stable
positions (FIG. 5(a): first position; FIG. 5(b): second position)
that can be used for carrying a sample in embodiments of the
present invention.
[0023] FIG. 6 shows a flowchart of one embodiment of a method of
electrochemically processing non-flat samples and/or samples that
can change shape during processing.
DETAILED DESCRIPTION OF CERTAIN ILLUSTRATIVE EMBODIMENTS
[0024] The present invention will be described with respect to
particular embodiments and with reference to certain drawings but
the invention is not limited thereto. The drawings described are
only schematic and are non-limiting. In the drawings, the size of
some of the elements may be exaggerated and not drawn on scale for
illustrative purposes. The dimensions and the relative dimensions
do not correspond to actual reductions to practice of the
invention. In the different drawings, the same reference signs
refer to the same or analogous elements. Any reference signs in the
claims shall not be construed as limiting the scope.
[0025] Furthermore, the terms first, second, third and the like in
the description, are used for distinguishing between similar
elements and not necessarily for describing a sequence, either
temporally, spatially, in ranking or in any other manner. It is to
be understood that the terms so used are interchangeable under
appropriate circumstances and that the embodiments of the invention
described herein are capable of operation in other sequences than
described or illustrated herein.
[0026] Moreover, the terms top, bottom, over, under and the like in
the description are used for descriptive purposes and not
necessarily for describing relative positions. It is to be
understood that the terms so used are interchangeable under
appropriate circumstances and that the embodiments of the invention
described herein are capable of operation in other orientations
than described or illustrated herein.
[0027] It is to be noticed that the term "comprising" should not be
interpreted as being restricted to the means listed thereafter; it
does not exclude other elements or steps. It is thus to be
interpreted as specifying the presence of the stated features,
integers, steps or components as referred to, but does not preclude
the presence or addition of one or more other features, integers,
steps or components, or groups thereof. Thus, the scope of the
expression "a device comprising means A and B" should not be
limited to devices consisting only of components A and B. It means
that with respect to the present invention, the only relevant
components of the device are A and B.
[0028] Reference throughout this specification to "one embodiment"
or "an embodiment" means that a particular feature, structure or
characteristic described in connection with the embodiment is
included in at least one embodiment of the present invention. Thus,
appearances of the phrases "in one embodiment" or "in an
embodiment" in various places throughout this specification are not
necessarily all referring to the same embodiment, but may.
Furthermore, the particular features, structures or characteristics
may be combined in any suitable manner, as would be apparent to one
of ordinary skill in the art from this disclosure, in one or more
embodiments.
[0029] Furthermore, while some embodiments described herein include
some but not other features included in other embodiments,
combinations of features of different embodiments are meant to be
within the scope of the invention, and form different embodiments,
as would be understood by those in the art.
[0030] In the description provided herein, numerous specific
details are set forth. However, it is understood that embodiments
of the invention may be practiced without these specific details.
In other instances, well-known methods, structures and techniques
have not been shown in detail in order not to obscure an
understanding of this description.
[0031] The invention will now be described by a detailed
description of several embodiments of the invention. It is clear
that other embodiments of the invention can be configured according
to the knowledge of persons skilled in the art without departing
from the true spirit or technical teaching of the invention, the
invention only being limited by the appended claims.
[0032] Certain embodiments of the present invention relate to a
method and a system for holding non-flat samples during
electrochemical processing (e.g. electrochemical etching,
electrochemical plating or electrochemical cleaning), wherein the
samples can be substantially non-flat and/or wherein the samples
can change shape (e.g. become more flat) during the electrochemical
process. In one embodiment, the system allows holding the non-flat
samples with a low risk of breakage and it allows providing and
maintaining an electrical contact to the samples during the whole
electrochemical process. For example, if the sample is initially
rolled up, it can unroll during the electrochemical process, e.g.
etching process, without losing the electrical contact. In one
embodiment, the system allows electrochemical etching or cleaning
of fragile samples with a low risk of breakage, for example of
samples, for example semiconductor material samples such as silicon
samples, with a thickness below 100 .mu.m.
[0033] A system according to one embodiment of the present
invention comprises a sample holder comprising a carrying element
such as e.g. a grid for carrying and mechanically supporting the
(substantially) non-flat sample, and a fixing element such as e.g.
a wire or a rod to fix the sample on the carrying element e.g.
during an electrochemical process, thereby allowing clamping the
sample in between the fixing element and the carrying element. At
least one of the carrying element and the fixing element is
electrically conductive and provides an electrical contact to the
sample during electrochemical processing. During electrochemical
processing the sample, e.g. non-flat sample, is located and fixed
in between the carrying element and the fixing element.
[0034] The system is further described for a particular embodiment
wherein the carrying element is an electrically conductive element,
e.g. a metallic grid, carrying the (substantially) non-flat sample
and providing an electrical contact to the sample during
electrochemical processing, and wherein the fixing element is
electrically non-conductive. However, the invention is not limited
thereto.
[0035] The invention is further described for the exemplary
embodiment wherein the system is used for holding a sample
comprising a thin silicon layer (e.g. a silicon layer with a
thickness lower than 100 micrometer, e.g. lower than 80 micrometer,
e.g. lower than 60 micrometer) and at least one metallic layer, the
sample being bent in one direction, and for electrochemically
etching the at least one metallic layer from the silicon layer.
Such a sample comprising a thin silicon layer and at least one
metallic layer may for example result from a SLIM-cut process (as
described in US 2007/0249140, which is incorporated herein by
reference in its entirety). Before further processing of such a
sample after release from a mother substrate, e.g. for making a
photovoltaic cell in the thin silicon layer, the at least one
metallic layer needs to be removed at least partially. Certain
embodiments of the present invention relate to methods and systems
for removing the at least one metallic layer by electrochemical
etching. Due to stress in the silicon/metal sample, the sample is
initially curled or rolled up, e.g. in a cylindrical shape. During
the etching process the stress is released and the sample may
change its shape, e.g. from a cylindrical shape to a substantially
flat or flat shape or to a cylindrical shape with a larger radius.
In one embodiment, a sample holder allows uncurling of the sample
during the electrochemical process, e.g. electrochemical etching
process. During the electrochemical process an electrical contact
to the sample is provided, and it is maintained even when the
sample is changing shape, e.g. when it is uncurling.
[0036] US Patent Application 2007/0249140 is incorporated herein by
reference in its entirety. To the extent this patent application
contradicts the disclosure contained in this specification, this
specification is intended to supersede and/or take precedence over
any such contradictory material.
[0037] FIG. 1 and FIG. 2 show schematic drawings illustrating a
system according to an embodiment of the present invention, wherein
a curled sample 1 comprising a thin silicon layer and at least one
metal layer can be etched, i.e. wherein the at least one metal
layer can be removed from the sample. FIGS. 1(a) and 2(a) show a
cross section of the system along the y-direction, the y-direction
being a direction in which the sample is not bent or curled. FIGS.
1(b) and 2(b) show a cross section of the system along the
x-direction, the x-direction being a direction in which the sample
is bent or curled and being substantially orthogonal to the
y-direction. An electrochemical etching solution 2, such as e.g. a
salt/acid aqueous solution, also called electrolyte, is provided in
a container 8, e.g. a beaker made of a material or coated with a
material that is not damaged by the electrochemical etching
solution, such as for example glass or plastic. In the example
shown, at the bottom of the container 8 a platform 3 is provided.
This platform 3 can for example have a square shape in a plane
parallel to the container bottom and it can for example be bent in
one direction. In the embodiment illustrated in FIG. 1 and FIG. 2,
the platform 3 is bent along the x-direction and not along the
y-direction. However, other shapes of the platform 3 can be
used.
[0038] As further illustrated, the platform 3 is used to reverse
the bending direction of a carrying element, e.g. grid 4, carrying
the sample 1 to be etched. This leads to good fixing of the sample
between the grid 4 and a fixing element, e.g wire 5, and thus to
good electrical contact to the clamped sample 1. Therefore, the
shape of the platform 3 may be compatible with the shape of the
grid 4.
[0039] However, in certain embodiments of the present invention
methods other than the use of a platform 3 can be used to reverse
the bending direction of a carrying element 4, e.g. grid. For
example, as illustrated in FIG. 5, a flexible carrying element 4,
e.g. grid, can be clamped in a frame 10 of smaller dimensions than
the carrying element 4 such that the carrying element 4 can be in
two different stable positions, each stable position corresponding
to a different bending direction of the carrying element. The
carrying element 4 can be bent in a first direction, e.g. as
illustrated for example in FIG. 5(b), when introducing the sample 1
in the electrochemical processing solution or when removing the
sample from the electrochemical processing solution. The carrying
element 4 can be bent in a second, different, direction during
electrochemical processing, as illustrated for example in FIG.
5(a). In such an embodiment there is no need for providing a
platform 3 in the container 8. The switching from bending
direction, e.g. from the first direction towards the second
direction, may be triggered by the carrying element 4 touching the
bottom of the container 8. In certain embodiments of the present
invention a substantially flat carrying element 4 can be used, such
that there is no need for reversing a bending direction.
[0040] FIG. 1 shows a system according to an embodiment of the
present invention during introduction of the sample 1 into the
container 8 comprising the etching solution 2. FIG. 1(a) shows a
cross-section along the y-direction; FIG. 1(b) shows a
cross-section along the x-direction. In the example shown, the
sample is introduced in such a way that the direction in which it
is bent is aligned with the direction in which the platform 3 is
bent (in the example illustrated the x-direction). The sample 1, in
the example shown a cylindrically curled sample 1, is placed on a
holder comprising an electrically conductive bendable carrying
element, such as a grid 4, e.g. an electrically conductive grid
such as a metallic grid 4. Other electrically conductive materials
may be used for forming the grid 4. In particular embodiments, the
curvature of the cylindrical sample has a smaller diameter than the
curvature of the carrying element 4. Instead of a grid 4, any
flexible and electrically conductive substrate may be used.
However, a grid 4 is advantageous as it may improve liquid flows
and release of bubbles. The sample 1 is kept in place on the grid 4
by means of a fixing element 5, for example a linear fixing element
e.g. a wire 5. Instead of a wire 5, other fixing elements can be
used, such as for example a rod or two small fixing elements, one
at or close to two opposite extremities of the sample. The fixing
element can be a rigid element or a flexible element or can be made
of a material that allows some degree of deformation (such as e.g.
rubber or foam). The fixing element can be attached to the grid or
it can be a separate element. As illustrated in FIG. 1(b), the
sample 1 is bent in one direction and the wire 5 is oriented in a
direction that is substantially equal to a direction in which the
sample 1 is not bent. A handler 7 can be attached to the holder, to
enable easy handling of the holder comprising the carrying element
4 and the fixing element 5.
[0041] FIG. 2 shows the system during electrochemical etching. FIG.
2(a) shows a cross-section along the y-direction; FIG. 2(b) shows a
cross-section along the x-direction. The carrying element 4, e.g.
bendable grid 4, is pushed to the platform 3 at the bottom of the
container 8, such that it follows the shape of the platform 3. In
particular embodiments the carrying element, e.g. grid 4, is
electrically conductive and provides an electrical contact to the
sample 1 to enable electrochemical processing. During
electrochemical processing, e.g. etching, the conductive carrying
element, e.g. grid 4, and the wire 5 are pushed towards one
another, thereby clamping the sample 1 and ensuring good electrical
contact to the sample. In the etching solution 2 an electrode, e.g.
negative electrode 6, is provided. The negative electrode 6 can for
example be in the form of a plate or a grid and is made of an
electrically conductive material, such as for example stainless
steel or any other electrically conductive material that is
resistant to the electrochemical process. When the electrode 6 is
in the form of a grid, bubbles or gases resulting from the etching
process can easily escape.
[0042] FIG. 3 shows the system with the holder and the sample after
electrochemical etching. A cross section along the x-direction is
shown, i.e. along the direction in which the sample was initially
bent. In this particular example, after removing the metallic layer
from the sample, the sample is substantially uncurled. It can be
removed from the etching bath by means of the holder comprising the
carrying element 4 and the handler 7. After electrochemical
etching, the etched sample can be fragile, for example it can be a
thin silicon layer (e.g. a few tens of micrometers thick).
[0043] In certain embodiments of the present invention the shape of
the platform 3 and the carrying element 4 may for example be
rectangular, wherein the platform is bent in one direction.
However, other shapes are possible, such as a circular shape, en
elliptical shape, a polygon shape, etc.
[0044] Although in FIGS. 1 to 3 a horizontal implementation of a
system according to one embodiment of the present invention is
shown, other implementations are possible. For example, to easily
remove compounds, e.g. salts, that may be formed during
electrochemical processing, a vertical implementation can be used
allowing these compounds to fall on the bottom of the beaker e.g.
by gravity. In this case a platform 3 would not be provided at the
bottom of the container 8 but it could be clamped to the grid
holder, as illustrated in FIG. 4.
[0045] FIG. 6 shows a flowchart of one embodiment of a method of
electrochemically processing non-flat samples and/or samples that
can change shape during processing. The method 100 includes, at a
block 110, clamping a sample between a grid-shaped carrying element
and a fixing element at at least one point, thus providing an
electrical contact to the sample. Moving to a block 120, the method
may further include electrochemically processing the clamped
sample, while allowing the electrochemically processed sample to
change shape without interrupting the electrical contact.
[0046] The foregoing description details certain embodiments of the
invention. It will be appreciated, however, that no matter how
detailed the foregoing appears in text, the invention may be
practiced in many ways. It should be noted that the use of
particular terminology when describing certain features or aspects
of the invention should not be taken to imply that the terminology
is being re-defined herein to be restricted to including any
specific characteristics of the features or aspects of the
invention with which that terminology is associated.
[0047] While the above detailed description has shown, described,
and pointed out novel features of the invention as applied to
various embodiments, it will be understood that various omissions,
substitutions, and changes in the form and details of the device or
process illustrated may be made by those skilled in the technology
without departing from the spirit of the invention. The scope of
the invention is indicated by the appended claims rather than by
the foregoing description. All changes which come within the
meaning and range of equivalency of the claims are to be embraced
within their scope.
* * * * *