U.S. patent application number 15/355554 was filed with the patent office on 2017-03-09 for patterned thin foil.
This patent application is currently assigned to SunPower Corporation. The applicant listed for this patent is SunPower Corporation. Invention is credited to Gabriel HARLEY, David F. J. KAVULAK, Taeseok KIM, Thomas PASS, Richard SEWELL, Xiuwen TU.
Application Number | 20170069777 15/355554 |
Document ID | / |
Family ID | 52114414 |
Filed Date | 2017-03-09 |
United States Patent
Application |
20170069777 |
Kind Code |
A1 |
PASS; Thomas ; et
al. |
March 9, 2017 |
PATTERNED THIN FOIL
Abstract
An adhesive may be applied to a surface of a reusable carrier.
Metal foil may be attached to the adhesive to couple the metal foil
to the surface of the reusable carrier. The metal foil may be
patterned without damaging the reusable carrier. A semiconductor
structure (e.g., a solar cell) may be attached to the patterned
metal foil. The reusable carrier may then be removed. In some
embodiments, the semiconductor structure may be encapsulated using
an encapsulant, with the adhesive being compatible with the
encapsulant.
Inventors: |
PASS; Thomas; (San Jose,
CA) ; SEWELL; Richard; (Los Altos, CA) ; KIM;
Taeseok; (Pleasanton, CA) ; HARLEY; Gabriel;
(Mountain View, CA) ; KAVULAK; David F. J.;
(Fremont, CA) ; TU; Xiuwen; (San Jose,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SunPower Corporation |
San Jose |
CA |
US |
|
|
Assignee: |
SunPower Corporation
San Jose
CA
|
Family ID: |
52114414 |
Appl. No.: |
15/355554 |
Filed: |
November 18, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13931538 |
Jun 28, 2013 |
9502596 |
|
|
15355554 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 31/048 20130101;
H01L 31/0512 20130101; H01L 31/0516 20130101; Y02E 10/50 20130101;
H01L 31/0488 20130101; H01L 31/1876 20130101; H01L 31/049 20141201;
Y02P 70/521 20151101; Y02E 10/547 20130101; Y02P 70/50
20151101 |
International
Class: |
H01L 31/05 20060101
H01L031/05; H01L 31/048 20060101 H01L031/048; H01L 31/049 20060101
H01L031/049 |
Claims
1. A solar module comprising: a first solar cell and a second solar
cell; a metal foil comprising a first surface and an opposing
second surface, the first and second solar cells being electrically
connected to the first surface of the metal foil; and an adhesive
layer on the second surface of the metal foil.
2. The solar module of claim 1, further comprising an encapsulant
that encapsulates at least the first solar cell, the second solar
cell, the metal foil, and the adhesive layer.
3. The solar module of claim 2, further comprising: a cover layer
on a surface of the encapsulant on front sides of the first and
second solar cells; and a backsheet on a surface of the encapsulant
on backsides of the first and second solar cells.
4. The solar module of claim 3, wherein the cover layer comprises
glass.
5. The solar module of claim 3, wherein the cover layer comprises
colored glass.
6. The solar module of claim 3, wherein the cover layer has
different colors on different areas of the cover layer.
7. The solar module of claim 2, wherein the layer of adhesive is
optically transparent to an attachment laser.
8. The solar module of claim 2, wherein the adhesive layer is
opaque to a patterning laser.
9. The solar module of claim 1, wherein the metal foil includes
regions not covered by any solar cell in the solar module.
10. A solar module comprising: a plurality of solar cells; a metal
foil that interconnects the plurality of solar cells; an adhesive
layer on a side of the metal foil that is away from the plurality
of solar cells; an encapsulant that encapsulates the plurality of
solar cells, the metal foil, and the adhesive layer; and a cover
layer on front sides of the plurality of solar cells.
11. The solar module of claim 10, wherein the cover layer is
colored.
12. The solar module of claim 10, wherein the cover layer has
different colors on different areas of the cover layer.
13. The solar module of claim 10, wherein the cover layer comprises
glass.
14. The solar module of claim 10, wherein the adhesive layer is
opaque to a patterning laser.
15. The solar module of claim 10, wherein the adhesive layer is
optically transparent to an attachment laser.
16. A solar module comprising: a cover layer; a backsheet; and an
encapsulant between the cover layer and the backsheet, the
encapsulant encapsulating a plurality of solar cells, a metal foil,
and an adhesive layer that is on surface of the metal foil.
17. The solar module of claim 16, wherein the cover layer is
colored.
18. The solar module of claim 16, wherein the cover layer has
different colors on different areas of the cover layer.
19. The solar module of claim 16, wherein the metal foil is
optically transparent to a laser.
20. The solar module of claim 16, wherein the metal foil has
regions that are not covered by any solar cell in the solar cell
module.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 13/931,538, filed on Jun. 28, 2013, which is incorporated
herein by reference in its entirety.
BACKGROUND
[0002] Semiconductors are widely used in most of electronic devices
today. Some examples of semiconductor structures include diodes,
light emitting diodes, and solar cells. Solar cells are well known
devices for converting solar radiation to electrical energy. They
can be fabricated on a semiconductor wafer using semiconductor
processing technology. A solar cell includes P-type and N-type
diffusion regions. Solar radiation impinging on the solar cell
creates electrons and holes that migrate to the diffusion regions,
thereby creating voltage differentials between the diffusion
regions. In a backside contact solar cell, both the diffusion
regions and the metal contact fingers coupled to them are on the
backside of the solar cell. The contact regions and contact fingers
allow an external electrical circuit to be coupled to and be
powered by the solar cell.
[0003] In some instances, the electrical circuit for solar modules
may be divided between the solar cell components and the solar
module components. For example, a portion of the electrical circuit
may reside at the solar cell component level. That portion may be
referred to as the M1 layer. Another portion of the electrical
circuit may reside at the module component level and may be
referred to as the M2 layer. However, implementation of an M2 layer
can be cost prohibitive.
BRIEF SUMMARY
[0004] This disclosure describes techniques and structures for
using patterned thin foil as a metal layer in semiconductors. In
one embodiment, an adhesive may be applied to a surface of a
reusable carrier. Metal foil may be attached to the adhesive to
couple the metal foil to the surface of the reusable carrier. The
metal foil may be patterned without damaging the reusable carrier.
A semiconductor (e.g., a solar cell) may be attached to the
patterned metal foil. The reusable carrier may then be removed. In
some embodiments, the solar cell may be encapsulated with an
encapsulant. The adhesive may be compatible with the
encapsulant.
[0005] In one embodiment, a metal layer may be coupled to a surface
of a carrier via an adhesive layer that is compatible with an
encapsulant of a solar module. First and second portions of the
metal layer may be patterned and first and second solar cells may
be coupled to the first and second patterned portions,
respectively. In various embodiments, the carrier may then be
removed.
[0006] In one embodiment, an encapsulant-compliant adhesive may be
applied to a reusable carrier. A metal foil may then be attached to
the encapsulant-compliant adhesive. The metal foil may be
patterned. A wafer may be attached to the patterned metal foil and
the reusable carrier may be removed. In one embodiment, at least
some of the encapsulant-compliant adhesive may remain on the
patterned metal foil after removing the reusable carrier.
[0007] This summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the detailed description. This summary is not intended to identify
key features or essential features of the claimed subject matter,
nor is it intended to be used as an aid in determining the scope of
the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] A more complete understanding of the subject matter may be
derived by referring to the detailed description and claims when
considered in conjunction with the following figures, wherein like
reference numbers refer to similar elements throughout the
figures.
[0009] FIG. 1 is a flow chart illustrating a method for using
patterned thin foil as a metal layer in semiconductor structures,
according to some embodiments.
[0010] FIG. 2 is a cross-sectional representation of a solar cell
attached to patterned metal foil, according to various
embodiments.
[0011] FIG. 3 is a top view representation of attaching a solar
cell to patterned metal foil, according to various embodiments.
[0012] FIG. 4 is a cross-sectional representation of a solar cell
attached to patterned metal foil, according to various
embodiments.
[0013] FIG. 5 is a cross-sectional representation of a solar module
that includes solar cells attached to patterned thin foil.
DETAILED DESCRIPTION
[0014] The following detailed description is merely illustrative in
nature and is not intended to limit the embodiments of the subject
matter or the application and uses of such embodiments. As used
herein, the word "exemplary" means "serving as an example,
instance, or illustration." Any implementation described herein as
exemplary is not necessarily to be construed as preferred or
advantageous over other implementations. Furthermore, there is no
intention to be bound by any expressed or implied theory presented
in the preceding technical field, background, brief summary or the
following detailed description.
[0015] This specification includes references to "one embodiment"
or "an embodiment." The appearances of the phrases "in one
embodiment" or "in an embodiment" do not necessarily refer to the
same embodiment. Particular features, structures, or
characteristics may be combined in any suitable manner consistent
with this disclosure.
[0016] Terminology. The following paragraphs provide definitions
and/or context for terms found in this disclosure (including the
appended claims):
[0017] "Comprising." This term is open-ended. As used in the
appended claims, this term does not foreclose additional structure
or steps.
[0018] "Configured To." Various units or components may be
described or claimed as "configured to" perform a task or tasks. In
such contexts, "configured to" is used to connote structure by
indicating that the units/components include structure that
performs those task or tasks during operation. As such, the
unit/component can be said to be configured to perform the task
even when the specified unit/component is not currently operational
(e.g., is not on/active). Reciting that a unit/circuit/component is
"configured to" perform one or more tasks is expressly intended not
to invoke 35 U.S.C. .sctn.112, sixth paragraph, for that
unit/component.
[0019] "First," "Second," etc. As used herein, these terms are used
as labels for nouns that they precede, and do not imply any type of
ordering (e.g., spatial, temporal, logical, etc.). For example,
reference to a "first" solar cell does not necessarily imply that
this solar cell is the first solar cell in a sequence; instead the
term "first" is used to differentiate this solar cell from another
solar cell (e.g., a "second" solar cell).
[0020] "Based On." As used herein, this term is used to describe
one or more factors that affect a determination. This term does not
foreclose additional factors that may affect a determination. That
is, a determination may be solely based on those factors or based,
at least in part, on those factors. Consider the phrase "determine
A based on B." While B may be a factor that affects the
determination of A, such a phrase does not foreclose the
determination of A from also being based on C. In other instances,
A may be determined based solely on B.
[0021] "Coupled"--The following description refers to elements or
nodes or features being "coupled" together. As used herein, unless
expressly stated otherwise, "coupled" means that one
element/node/feature is directly or indirectly joined to (or
directly or indirectly communicates with) another
element/node/feature, and not necessarily mechanically.
[0022] In addition, certain terminology may also be used in the
following description for the purpose of reference only, and thus
are not intended to be limiting. For example, terms such as
"upper", "lower", "above", and "below" refer to directions in the
drawings to which reference is made. Terms such as "front", "back",
"rear", "side", "outboard", and "inboard" describe the orientation
and/or location of portions of the component within a consistent
but arbitrary frame of reference which is made clear by reference
to the text and the associated drawings describing the component
under discussion. Such terminology may include the words
specifically mentioned above, derivatives thereof, and words of
similar import.
[0023] Although much of the disclosure is described in terms of
solar cells, strings of solar cells, and solar modules that include
solar cells for ease of understanding, the disclosed techniques and
structures apply equally to other semiconductor structures (e.g.,
silicon wafers generally).
[0024] Turning now to FIG. 1, a flow chart illustrating a method
for using patterned thin foil as a metal layer in solar cells is
shown, according to some embodiments. In various embodiments, the
method of FIG. 1 may include additional (or fewer) blocks than
illustrated. For example, in one embodiment, the metal foil may be
pre-patterned, as described below. In such an embodiment, block 106
may not be necessary (or may supplement the pre-patterning).
[0025] As shown at 102, an adhesive, which may also be referred to
as an adhesive layer, may be applied to a surface of a reusable
carrier. In various embodiments, the adhesive may be compatible
with an encapsulant (e.g., XUR, EVA, etc.) used to encapsulate
solar cells. The term compatible or compliant with the encapsulant
is used herein to mean that the adhesive has electrical,
mechanical, and/or chemical, etc. properties that are similar to
and/or do not adversely affect the properties of the encapsulant.
For example, the encapsulant-compliant adhesive and the encapsulant
may have similar curing properties. In one embodiment, the adhesive
may even have properties that synergistically enhance or improve
the properties of the encapsulant.
[0026] In one embodiment, the adhesive may be a liquid or solid
adhesive that is usable to create a thin uniform layer of the
adhesive that adheres to the surface of the reusable carrier. The
adhesive layer may be a thin material that is less than the
thickness of the encapsulant. Examples of an encapsulant-compliant
adhesive include hot melt adhesive (HMA), liquid silicon, etc. In
various embodiments, the adhesive may include other properties as
well, such as being optically transparent to an attachment laser
(e.g., a laser performing attachment of the solar cell to the foil)
and/or optically opaque to the patterning laser (e.g., laser
performing the patterning of the foil).
[0027] At 104, a metal foil may be attached to the adhesive to
couple the metal foil to the surface of the reusable carrier.
Attaching the metal foil may include rolling a thin metal foil
layer onto the adhesive resulting in the metal foil having a
smooth, uniform, and planar surface. In some embodiments, the metal
foil may be a single continuous piece of metal foil. The attachment
of the metal foil to the adhesive may be referred to a loose
attachment/adhering such that the metal foil may be removed from
the reusable carrier without significant effort (e.g., by peeling
and not requiring a large amount of force) yet may be adhered
enough to hold the foil in place for patterning the foil and
attaching the cell to the foil.
[0028] As illustrated at 106, the metal foil may be patterned. The
resulting patterned metal foil may be an M2 layer that is usable
with an M1 layer of the solar cells. In one embodiment, patterning
the metal foil may include ablating the metal foil with a laser in
a subtractive patterning process. The patterning laser may be
positioned above (offset or directly above) the foil and lase into
the foil. Alternatively, the patterning laser may be positioned to
the side of the foil and carrier. In one embodiment, the adherent
may be opaque to the patterning laser to effectively prevent the
patterning laser from damaging the reusable carrier such that the
carrier may be reused. In one embodiment, patterning the metal foil
may include absorbing metal removed during the patterning process
into the adhesive, which may minimize debris collection by removing
the absorbed metal when the carrier is removed at block 110, as
described below.
[0029] In one embodiment, patterning may be custom based on the
individual solar cell to account for minor variations from cell to
cell. For example, a solar cell may be imaged (e.g., by a high
resolution camera or other imaging device) such that its
dimensions, finger locations, etc. are precisely and uniquely
measured/determined. Patterning of the foil may then be based on
the imaged solar cell (e.g., based on the information regarding
precise locations/layout of the particular solar cell) such that
the patterned foil matches the imaged solar cell to improve
alignment from solar cell to patterned foil and minimize
distortion.
[0030] In one embodiment, custom patterning may be performed for
each solar cell. In another embodiment, custom patterning may be
performed for a particular solar cell of a batch of solar cells and
the metal foil may be patterned for the remainder of the solar
cells of the batch according to the custom pattern for that
particular solar cell. Other variations for custom patterning may
also exist. For instance, the solar cells may be imaged as part of
the registering or aligning the solar cells to the patterned foil.
If various landmarks of a solar cell fall outside a tolerance
limit, custom patterning of the foil may be performed. Otherwise,
if the various landmarks fall within the tolerance limit, a generic
patterning or previous custom patterning (as based on another
particular solar cell) may be performed. Accordingly, custom
patterning may be performed periodically (e.g., for a particular
ratio of solar cells), for each solar cell, or based on the
individual solar cell.
[0031] Note that, in some embodiments, the metal foil may be
pre-patterned. In such embodiments, block 106 of the method of FIG.
1 may be omitted. Or, in one embodiment, the pre-patterning may not
be complete such that additional patterning may be performed at
block 106 to complete the patterning of the metal foil. Various
examples are discussed below.
[0032] As shown at 108, a solar cell (or multiple solar cells) may
be attached to the patterned metal foil. For example, the solar
cell(s) may be attached to the patterned metal foil through thermal
welding, laser welding, soldering, and/or other attachment
techniques. In an embodiment in which the foil is a single
continuous piece of metal foil, the multiple solar cells may be
attached to the single continuous piece of metal foil. As described
herein, coupling of the solar cell to the patterned foil may
complete the circuit from the M1 layer of the cell to the M2 layer
of the patterned foil.
[0033] In one embodiment, the laser that is used for attaching the
solar cells to the metal foil may lase through the carrier and
through the adherent such that the bond from M1 to M2 may be
performed. Thus, in one embodiment, the adherent (and the reusable
carrier) may be transparent to the attachment laser (note again,
that the adherent may be opaque to the patterning laser). The laser
used for attachment may be chosen and/or configured (e.g.,
wavelength, etc.) such that the reusable carrier is not damaged and
may be reused.
[0034] In various embodiments, the solar cell may be aligned to the
stationary (during alignment) patterned metal foil prior to
attaching, whereas in other embodiments, the metal foil may be
aligned to the stationary (during alignment) solar cell. Aligning
the solar cell may include picking up the cell, chucking the cell,
using an imaging device (e.g., camera, laser, etc.) to determine
various landmarks in the solar cell to be aligned precisely to the
metal foil. Collectively, the picking up, chucking, imaging,
aligning, and placing the cell may be performed by a precision
movement system. Note that in the custom patterning embodiments
described above, some portions of the precision movement system may
take place prior to patterning. For example, imaging the solar cell
may take place before patterning and may not need to be repeated at
block 108.
[0035] In various embodiments in which multiple solar cells/wafers
are attached to the metal foil, the solar cells/wafers may be
electrically coupled to one another. As a simple illustrative
example using two solar cells, attaching the first and second solar
cells to the metal foil may also include electrically coupling the
first solar cell to the second solar cell. Accordingly, attaching
the solar cells together may result in a string of solar cells. In
one embodiment, the patterning of the foil may include additional
M2 layer patterning that completes the electrical connection
between the first and second solar cells. In another embodiment,
the electrical coupling of the first and second solar cells may not
take place in the patterning of the foil.
[0036] Patterning the foil for multiple solar cells may be
performed before attaching those solar cells. Consider a simple
example using four solar cells to illustrate such patterning and
attaching. The metal foil may be patterned for all four solar cells
and then the four solar cells may be attached to the pattern metal
foil. In another embodiment, patterning and attaching may alternate
such that a first portion of the foil may be patterned for the
first solar cell, the first solar cell may be attached to the
patterned first portion, a second portion of the foil may be
patterned for the second solar cell, the second solar cell may be
attached to the patterned second portion, and so on. As noted
above, the different portions of patterned metal foil may be
patterned differently such that the first portion is patterned
differently than the second portion (e.g., for custom
patterning).
[0037] At 110, after the metal foil has been patterned and after
the solar cell(s) have been attached to the patterned foil, the
reusable carrier may be removed from the solar cell/patterned foil
assembly. In various embodiments, the reusable carrier may be
manually removed (e.g., peeled), thermally delaminated, among other
techniques.
[0038] In one embodiment, removing the reusable carrier may result
in at least a portion of the adhesive remaining on the metal foil
and another portion remaining on the reusable carrier. As described
herein, because the adherent is compliant with the encapsulant used
to encapsulate the solar cells, the adherent that remains on the
metal foil may not negatively affect operation of the cell or
module. The reusable carrier may be cleaned (e.g., chemically,
mechanically, etc.) of its remaining adherent and it may then be
reused.
[0039] As illustrated at 112, the solar cell(s) may be encapsulated
with an encapsulant. As described herein, the adhesive may be
compatible/compliant with the encapsulant. Because the adhesive is
compliant with the encapsulant and because there is not a permanent
carrier as part of the final module assembly, the encapsulant may
completely or substantially fill the area between the external
components of the module (e.g., cover and back layer as shown in
FIG. 5) and the solar cell resulting in no or only minor voids in
the final module assembly.
[0040] In an alternative embodiment, a non-reusable carrier may be
used and still result in a module with minor or no voids. For
example, a flexible carrier, such as a polyester (PET) carrier, may
be used. The patterning laser may perforate the flexible carrier
thereby permitting encapsulant to substantially fill the voids in
the final module.
[0041] In yet another embodiment, no carrier may be used at all.
Instead, the foil may be rolled out directly on to a stringing
chuck (an example stringing chuck is depicted in FIG. 2) or other
surface, where the foil may be patterned (if not pre-patterned or,
in some cases, even if pre-patterned), and then connected to the
solar cell as described herein. In such an embodiment, the
stringing chuck may need to be cleaned periodically (e.g., after
each string of solar cells is coupled to the foil) to remove any
adhesive. Note that if no carrier is used, however, adhesive may
not be used in some embodiments. Instead, the foil may be held to
the stringing chuck by vacuum or comparable technique.
[0042] In another embodiment in which no carrier and no adhesive
are used, the solar cell may be placed directly on the stringing
chuck or other processing surface followed by the foil being placed
on the solar cell. The foil may then be brought into intimate
(e.g., substantially complete, substantially uniform) contact with
the wafer. Bringing the foil into contact with the wafer may
performed by mechanical force that is sufficient to achieve
intimate contact between the foil and wafer. Examples of mechanical
force may include air (forced air or vacuum), pressing (e.g., the
wafer chuck or similar device pressing the foil and wafer against
the processing surface), etc. Bringing the foil into contact with
the wafer may be performed from above the foil or from below the
wafer. While the foil is held in intimate contact with the solar
cell, a laser may lase through the wafer chuck, which may be
optically transparent to the laser, to couple the foil to the
wafer. The foil may then be patterned. In one embodiment, the wafer
chuck may be removed before patterning. Note that, as described
herein, the foil may also be pre-patterned (e.g., dimpled,
embossed, weakened, perforated, etc.).
[0043] Note that in embodiments in which a laser lases through a
stringing chuck, the stringing chuck may likewise be optically
transparent to the laser.
[0044] The disclosed techniques may allow for metal foil to be used
as an M2 layer without the need for a permanent supporting base
material, yet provide for precise alignment of the solar cells to
the patterned foil with minimal distortion. Because the adherent is
compatible with the encapsulant, the portion of the adherent that
remains on the metal foil may not adversely affect operation of the
solar cell or module. Moreover, using a reusable carrier may lower
cost and because the carrier is not part of the module, the
possibility of voids in the final solar module may be eliminated or
greatly reduced.
[0045] FIG. 2 is a cross-sectional representation of a
semiconductor structure attached to patterned metal foil, according
to various embodiments. As shown, reusable carrier 212 may be
placed on stringing chuck 210. Reusable carrier 212 may be held in
place on stringing chuck 210 in a variety of manners, such as
vacuum, adhesive, clamped, mechanical force (e.g., from wafer chuck
220), etc. Adhesive 214 may be applied to reusable carrier 212 to
attach metal foil 216 to reusable carrier. As described herein,
metal foil 216 may be pre-patterned, or may be patterned after
being attached to the reusable carrier according to the techniques
described herein. As shown, wafer chuck 220, as part of a precision
movement system may position solar cells 218A, 218B, and 218C for
attachment to metal foil 216. Not shown in FIG. 2, a laser or other
device may be used to pattern metal foil 216 prior to attaching the
solar cells. Also not shown in FIG. 2, a laser, welder, or other
device may be used to attach the solar cells to metal foil 216.
[0046] FIG. 3 is a top view representation of attaching a
semiconductor wafer to patterned metal foil, according to various
embodiments. As shown from left to right, solar cell 218A (left
most portion of FIG. 3) is attached to patterned metal foil 216
(middle portion of FIG. 3) resulting in the string of solar cells
attached to the metal foil and one another, as shown in the right
most portion of FIG. 3. In the example of FIG. 3, patterned metal
foil 216 illustrates patterned P regions 310 and patterned N
regions 312 in a pattern that permits wafers to be flipped for
faster patterning. In another embodiment, a more traditional P/N
offset patterning may be used.
[0047] As shown in the right most image of FIG. 3, metal foil 216
may include diamond regions in which the solar cells to do not
completely cover the metal foil. In various embodiments, those
diamond regions of foil may be removed (e.g., by laser ablation)
after attaching the solar cells, or the foil may be partially
pre-patterned and not include those diamond portions of foil.
[0048] FIG. 4 is a cross-sectional representation of a
semiconductor attached to patterned metal foil, according to
various embodiments. As shown, the representation of stringed solar
cells in FIG. 4 is similar to that of FIG. 2 except that the
reusable carrier has been removed in FIG. 4. As shown, four solar
cells, solar cells 218A, 218B, 218C, and 218D are attached to metal
foil 216 and to each other. Also as shown, at least a portion of
adhesive 214 remains on the bottom of metal foil 216 after the
reusable carrier has been removed.
[0049] FIG. 5 is a cross-sectional representation of a solar module
that includes the stringed solar cells of FIG. 4. As shown in FIG.
5, the stringed solar cells have been encapsulated with encapsulant
514. As described herein, adhesive 214 is compatible with
encapsulant 514. Also in FIG. 5, a back layer 512 is shown. In one
embodiment, back layer 512 may be a backsheet. The backsheet may be
any suitable type of backsheet that is capable of providing
environmental protection, mechanical stiffness, and/or electrical
insulation, etc.
[0050] Also shown in FIG. 5, cover layer 510 (e.g., glass) has been
added to the encapsulated solar cells to create a solar module. In
various embodiments, cover layer 510 may constructed of a clear, or
translucent, material, such as glass or a plastic. Various colors
of glass or plastic may be used for cover layer 510. In one
embodiment, different colors (e.g., white, black, etc.) may be used
in cover layer 510 (e.g., one color for the area corresponding to
solar cell locations and another color for the area corresponding
to the regions between solar cells). In various embodiments, cover
layer 510 may be treated and/or formulated with an anti-reflective
material or coating to inhibit loss of photons at the surface or,
or through, cover layer 510.
[0051] Although specific embodiments have been described above,
these embodiments are not intended to limit the scope of the
present disclosure, even where only a single embodiment is
described with respect to a particular feature. Examples of
features provided in the disclosure are intended to be illustrative
rather than restrictive unless stated otherwise. The above
description is intended to cover such alternatives, modifications,
and equivalents as would be apparent to a person skilled in the art
having the benefit of this disclosure.
[0052] The scope of the present disclosure includes any feature or
combination of features disclosed herein (either explicitly or
implicitly), or any generalization thereof, whether or not it
mitigates any or all of the problems addressed herein. Accordingly,
new claims may be formulated during prosecution of this application
(or an application claiming priority thereto) to any such
combination of features. In particular, with reference to the
appended claims, features from dependent claims may be combined
with those of the independent claims and features from respective
independent claims may be combined in any appropriate manner and
not merely in the specific combinations enumerated in the appended
claims.
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