U.S. patent application number 15/380677 was filed with the patent office on 2017-04-06 for solar cell apparatus and method of fabricating the same.
The applicant listed for this patent is LG INNOTEK CO., LTD.. Invention is credited to Chin Woo Lim.
Application Number | 20170098721 15/380677 |
Document ID | / |
Family ID | 48141107 |
Filed Date | 2017-04-06 |
United States Patent
Application |
20170098721 |
Kind Code |
A1 |
Lim; Chin Woo |
April 6, 2017 |
Solar Cell Apparatus and Method of Fabricating the Same
Abstract
According to the embodiment, there is provided a solar cell
apparatus. The solar cell apparatus includes a back electrode layer
on a substrate, a light absorbing layer on the back electrode
layer, a buffer layer on the light absorbing layer, a front
electrode layer on the buffer layer, and a connection part making
contact with the front electrode layer, passing through the light
absorbing layer, and making contact with the back electrode layer.
The connection part includes a material different from a material
constituting the front electrode layer.
Inventors: |
Lim; Chin Woo; (Seoul,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG INNOTEK CO., LTD. |
Seoul |
|
KR |
|
|
Family ID: |
48141107 |
Appl. No.: |
15/380677 |
Filed: |
December 15, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14352802 |
Apr 18, 2014 |
9559223 |
|
|
PCT/KR2012/008447 |
Oct 16, 2012 |
|
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15380677 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y02E 10/541 20130101;
Y02E 10/50 20130101; H01L 31/0749 20130101; H01L 31/0463 20141201;
H01L 31/02245 20130101; H01L 31/0465 20141201 |
International
Class: |
H01L 31/0224 20060101
H01L031/0224; H01L 31/0749 20060101 H01L031/0749; H01L 31/0463
20060101 H01L031/0463 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 18, 2011 |
KR |
10-2011-0106373 |
Claims
1. A solar cell apparatus comprising: a back electrode layer on a
substrate; a light absorbing layer on the back electrode layer; a
buffer layer on the light absorbing layer; a front electrode layer
on the buffer layer; a connection part making contact with the
front electrode layer, passing through the light absorbing layer,
and making contact with the back electrode layer; a first hole
passing through the back electrode layer, the light absorbing
layer, the buffer layer, and the front electrode layer; and a
second hole formed adjacent to the first hole while passing through
the light absorbing layer, the buffer layer, and the front
electrode layer, wherein the connection part includes a material
different from a material constituting the front electrode layer;
wherein a top surface of the connection part is higher than a top
surface of the front electrode layer; wherein the connection part
is disposed in the second hole, and spaced apart from the back
electrode layer on the first hole.
2. The solar cell apparatus of claim 1, wherein the connection part
includes metal.
3. The solar cell apparatus of claim 2, wherein the connection part
includes aluminum (Al), nickel (Ni), or silver (Ag).
4. The solar cell apparatus of claim 1, further comprising a third
hole formed beside the second hole while passing through the light
absorbing layer, the buffer layer, and the front electrode
layer.
5. The solar cell apparatus of claim 4, wherein the second hole is
overlapped with a third hole.
6. The solar cell apparatus of claim 1, a width of the first hole
and a width of the second hole are different.
7. The solar cell apparatus of claim 1, further comprising an
insulating part in the first hole.
8. The solar cell apparatus of claim 7, wherein the insulating part
includes a polymer or a ceramic material.
9. A solar cell apparatus comprising: a back electrode layer on a
substrate; a light absorbing layer on the back electrode layer; a
buffer layer on the light absorbing layer; a front electrode layer
on the buffer layer; a connection part making contact with the
front electrode layer, passing through the light absorbing layer,
and making contact with the back electrode layer; a first hole
passing through the back electrode layer, the light absorbing
layer, the buffer layer, and the front electrode layer; and a
second hole formed adjacent to the first hole while passing through
the light absorbing layer, the buffer layer, and the front
electrode layer wherein the connection part includes a material
different from a material constituting the front electrode layer;
wherein a top surface of the connection part is higher than a top
surface of the front electrode layer; wherein the connection part
includes a first portion overlapping with the first hole at a top
surface of the front electrode layer; and a second portion
overlapping with the second hole at a top surface of the front
electrode layer, wherein the first portion is spaced apart from the
back electrode layer, wherein the second portion makes contact with
the back electrode layer.
10. The solar cell apparatus of claim 9, wherein the second portion
is disposed in the second hole.
11. The solar cell apparatus claim 9, wherein the connection part
includes metal.
12. The solar cell apparatus of claim 11, wherein the connection
part includes aluminum (A nickel (Ni), or silver (Ag).
13. The solar cell apparatus of claim 9, further comprising a third
hole formed beside the second hole while passing through the light
absorbing layer, the buffer layer, and the front electrode
layer.
14. The solar cell apparatus of claim 13, wherein the second hole
is overlapped with a third hole.
15. The solar cell apparatus of claim 9, a width of the first hole
and a width of the second hole are different,
16. The solar cell apparatus of claim 9, further comprising an
insulating part in the first hole.
17. The solar cell apparatus of claim 16, wherein the insulating
part includes a polymer or a ceramic material.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is the continuation of U.S. application
Ser. No. 14/352,802, filed Apr. 18, 2014, which is the U.S.
national stage application of International Patent Application No.
PCT/KR2012/008447, filed Oct. 16, 2012, which claims priority to
Korean Application No. 10-2011-0106373, filed Oct. 18, 2011, the
disclosures of each of which are incorporated herein by reference
in their entirety.
TECHNICAL FIELD
[0002] The embodiment relates to a solar cell apparatus and a
method of fabricating the same.
BACKGROUND ART
[0003] A method of fabricating a solar cell for solar light power
generation is as follows. First, after preparing a substrate, a
back electrode layer is formed on the substrate and patterned by a
laser, thereby forming a plurality of back electrodes.
[0004] Thereafter, a light absorbing layer, a buffer layer, and a
high resistance buffer layer are sequentially formed on the back
electrodes. Various schemes, such as a scheme of forming a
Cu(In,Ga)Se2 (CIGS) based-light absorbing layer by simultaneously
or separately evaporating Cu, In, Ga, and Se and a scheme of
performing a selenization process after a metallic precursor film
has been formed, have been extensively used in order to form the
light absorbing layer. The energy band gap of the light absorbing
layer is in the range of about 1 eV to about 1.8 eV.
[0005] Then, a buffer layer including cadmium sulfide (CdS) is
formed on the light absorbing layer through a sputtering process.
The energy bandgap of the buffer layer may be in the range of about
2.2 eV to about 2.4 eV. After that, a high resistance buffer layer
including zinc oxide (ZnO) is formed on the buffer layer through
the sputtering process. The energy bandgap of the high resistance
buffer layer is in the range of about 3.1 eV to about 3.3 eV.
[0006] Thereafter, a groove pattern may be formed in the light
absorbing layer, the buffer layer, and the high resistance buffer
layer.
[0007] After that, a transparent conductive material is laminated
on the high resistance buffer layer, and is filled in the groove
pattern. Therefore, a transparent electrode layer is formed on the
high resistance buffer layer, and connection wires are formed in
the groove pattern. A material constituting the transparent
electrode layer and the connection wireless may include aluminum
doped zinc oxide (AZO). The energy bandgap of the transparent
electrode layer may be in the range of about 3.1 eV to about 3.3
eV.
[0008] Then, the groove pattern is formed in the transparent
electrode layer, so that a plurality of solar cells may be formed.
The transparent electrodes and the high resistance buffers
correspond to the cells, respectively. The transparent electrodes
and the high resistance buffers may be provided in the form of a
stripe or a matrix.
[0009] The transparent electrodes and the back electrodes are
misaligned from each other and electrically connected with each
other through the connection wires. Accordingly, the solar cells
may be electrically connected to each other in series.
[0010] As described above, in order to convert the solar light into
electrical energy, various solar cell apparatuses have been
fabricated and used. One of the solar cell apparatuses is disclosed
in Korean Unexamined Patent Publication No. 10-2008-0088744.
DISCLOSURE
Technical Problem
[0011] The embodiment provides a solar cell apparatus, capable of
preventing a short phenomenon with improved performance, and a
method of fabricating the same.
Technical Solution
[0012] According to the embodiment, there is provided a solar cell
apparatus. The solar cell apparatus includes a back electrode layer
on a substrate, a light absorbing layer on the back electrode
layer, a buffer layer on the light absorbing layer, a front
electrode layer on the buffer layer, and a connection part making
contact with the front electrode layer, passing through the light
absorbing layer, and making contact with the back electrode layer,
The connection part includes a material different from a material
constituting the front electrode layer.
[0013] According to the embodiment, there is provided a method of
fabricating the solar cell. The method includes forming a back
electrode layer on a substrate, forming a light absorbing layer on
the back electrode layer, forming a buffer layer on the light
absorbing layer, forming a front electrode layer on the buffer
layer, forming a second through hole passing through the light
absorbing layer, the buffer layer, and the front electrode layer
after forming the front electrode layer, and forming a connection
part in the second through hole. The connection part includes a
material different from a material constituting the front electrode
layer.
ADVANTAGEOUS EFFECTS
[0014] According to the present embodiment, a dead zone may be
reduced by the second and third through holes TH2 and TH3.
Accordingly, the density of short current can be improved, so that
the photo-electric conversion efficiency can be improved.
[0015] In addition, after a thin film deposition process has been
finished, the first to third through holes are formed at once, so
that the process time and the cost can be reduced. In addition,
since the first to third through holes are formed after the thin
film deposition process has been finished, the oxidation of the
back electrode layer and the front electrode layer can be
minimized. According, the contact resistance and the serial
resistance can be reduced, and the fill factor can be
increased.
[0016] Meanwhile, the insulating part is provided in the first
through holes. Accordingly, the leakage current can be reduced, and
the fill factor can be increased.
[0017] According to the method of fabricating the solar cell
apparatus of the embodiment, after the thin film deposition process
has been finished, since the first to third through holes are
patterned after the support substrate has been completely
heat-distorted, the application of the offset value is not
required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a plan view showing the panel of a solar cell
apparatus according to he first embodiment,
[0019] FIG. 2 is a sectional view taken along line A-A' of FIG.
1;
[0020] FIG. 3 is a sectional view showing the panel of a solar cell
apparatus according to the second embodiment;
[0021] FIGS. 4 to 8 are sectional views showing the fabricating
process of the panel of the solar cell apparatus according to the
first embodiment; and
[0022] FIGS. 9 to 11 are sectional views showing the fabricating
process of the panel of the solar cell apparatus according to the
second embodiment.
DETAILED DESCRIPTION
[0023] In the description of the embodiments, it will be understood
that, when a layer (film), a region, a pattern, or a structure, is
referred to as being e first to third through holes are patterned
after the support substrate haother pad, or another pattern, it can
be "directly" or "indirectly" on the other substrate, the other
layer (film), the other region, the other pad, or the other
pattern, one or more intervening layers may also be present. Such a
position of each layer has been described with reference to the
drawings.
[0024] The thickness and size of each layer (film), each region,
each pattern, or each structure shown in the drawings may be
exaggerated, omitted or schematically drawn for the purpose of
convenience or clarity. In addition, the size of each layer (film),
each region, each pattern, or each structure does not utterly
reflect an actual size.
[0025] Hereinafter, the embodiment of the disclosure will be
described in detail with reference to accompanying drawings.
[0026] First, hereinafter, the solar cell apparatus according to
the first embodiment will be described in detail. FIG. 1 is a plan
view showing the panel of a solar cell apparatus according to the
first embodiment, and FIG. 2 is a sectional view taken along line
A-A' of FIG. 1.
[0027] Referring to FIGS. 1 and 2, the solar cell apparatus
includes a support substrate 100, a back electrode layer 200, a
light absorbing layer 300, a buffer layer 400, a high resistance
buffer layer 500, a front electrode layer 600, an insulating part
700, and a plurality of connection parts 800.
[0028] The support substrate 100 has a plate shape and supports the
back electrode layer 200, the light absorbing layer 300, the buffer
layer 400, the high resistance buffer layer 500, the front
electrode layer 600, and the connection part 800.
[0029] The support substrate 100 may be an insulator. The support
substrate 100 may be a glass substrate, aplastic substrate or a
metal substrate. In detail, the support substrate 100 may be a soda
lime glass substrate. The support substrate 100 may be transparent.
The support substrate 100 may be rigid or flexible.
[0030] The back electrode layer 200 is provided on the support
substrate 100. The back electrode layer 200 is a conductive layer,
For example, a material constituting the back electrode layer 200
may include metal such as molybdenum (Mo).
[0031] The back electrode layer 200 may include two or more layers
In this case, the layers may be formed by the same metal or
different metals.
[0032] The back electrode layer 200 is provided therein with first
through holes TH1. The first through holes TH1 pass through the
back electrode layer 200, the light absorbing layer 300, the buffer
layer 400, and the front electrode layer 600. The first through
holes TH1 are open regions to expose the top surface of the support
substrate 100, When viewed in a plan view, first through holes TH1
may have a shape extending in one direction.
[0033] The first through holes TH1 may have a width in the range of
about 80 .mu.m to about 200 .mu.m.
[0034] The back electrode layer 200 is divided into a plurality of
back electrodes by the first through holes TH1. In other words, the
back electrodes are defined by the first through holes TH1.
[0035] The back electrodes are spaced apart from each other by the
first through holes TH1. The back electrodes are arranged in the
form of a stripe.
[0036] In addition, the back electrodes may be arranged in the form
of a matrix. In this case, when viewed in a plan view, the first
through holes TH1 may be provided in the form of a lattice.
[0037] Meanwhile, the insulating part 700 is provided in the first
through holes TH1. In addition, a portion of the connection part
800 may be provided in the first through holes TH1. In detail, the
connection part 800 may be provided on the insulating part 700.
Accordingly, leakage current can be reduced, and a fill factor can
be increased.
[0038] A top surface 710 of the insulating part 700 is higher than
a top surface 210 of the back electrode layer. Accordingly, the
back electrode layer 200 may be insulated from the connection part
800. The insulating part 700 may include polymer or a ceramic
material.
[0039] The light absorbing layer 300 is provided on the back
electrode layer 200.
[0040] The light absorbing layer 300 includes a group I-III-VI
compound. For example, the light absorbing layer 300 may have the
CIGSS (Cu(IN,Ga)(Se,S)2) crystal structure, the CISS
(Cu(IN)(Se,S)2) crystal structure or the CGSS (Cu(Ga)(Se,S)2)
crystal structure.
[0041] The energy bandgap of the light absorbing layer 300 may be
in the range of about 1 eV to about 1.8 eV.
[0042] The buffer layer 400 is provided on the light absorbing
layer 300. The buffer layer 400 includes cadmium sulfide (CdS). The
energy bandgap of the buffer layer 400 may be in the range of about
2.2 eV to about 2.4 eV.
[0043] The high resistance buffer layer 500 is provided on the
buffer layer 400. The high resistance buffer layer 500 includes
i-ZnO which is not doped with impurities. The energy bandgap of the
high resistance buffer layer 500 may be in the range of about 3.1
eV to about 3.3 eV.
[0044] The light absorbing layer 300, the buffer layer 400, the
high resistance buffer layer 500, and the front electrode layer 600
are formed therein with second through holes TH2. The second
through holes TH2 pass through the light absorbing layer 300, the
buffer layer 400, the high resistance buffer layer 500, and the
front electrode layer 600. In addition, the second through holes
TH2 are open regions to expose the top surface of the back
electrode layer 200.
[0045] The second through holes TH2 are adjacent to the first
through holes TH1. In other words, when viewed in a plan view,
portions of the second through holes TH2 are formed beside the
first through holes TH1. The second through holes TH2 have a shape
extending in a first direction.
[0046] Each second through hole TH2 may have a width in the range
of about 80 .mu.m to about 200 .mu.m.
[0047] A plurality of light absorbing parts 310, 320, 0 l and N are
defined in the light absorbing layer 300 by second through holes
TH2. In other words, the light absorbing layer 300 is divided into
the light absorbing parts 310, 320, 0 N by the second through holes
TH2.
[0048] A plurality of buffers are defined in the buffer layer 400
by the second through holes TH2. In other words, the buffer layer
400 is divided into a plurality of buffers by the second through
holes TH2.
[0049] A plurality of high resistance buffers are defined in the
high resistance buffer layer 500 by the second through holes TH2.
In other words, the high resistance buffer layer 500 is divided
into the high resistance buffers by the second through holes
TH2.
[0050] The front electrode layer 600 is provided on the high
resistance buffer layer 500. The front electrode layer 600 is
transparent, and includes a conductive layer. In addition, the
front electrode layer 600 has resistance greater than that of the
back electrode layer 200.
[0051] The front electrode layer 600 includes an oxide. For
example, the front electrode layer 600 may include an Al doped zinc
oxide (AZO), or a Ga doped zinc oxide (GZO).
[0052] The front electrode layer 600 has a thickness in the range
of about 0.5 .mu.m to about 1.5 .mu.m. The front electrode layer
600 is divided into a plurality of front electrodes by the second
through holes TH2. That is, the front electrodes are defined by the
second through holes TH2. Third through holes TH3 are formed beside
the second through holes TH2. The third through holes TH3 expose
the top surface 210 of the back electrode layer 200 and passes
through the light absorbing layer 300.
[0053] The front electrodes have a shape corresponding to that of
the back electrodes. In other words, the front electrodes are
disposed in the form of a stripe. Alternatively, the front
electrodes may be disposed in the form of a matrix.
[0054] In addition, a plurality of cells C1, C2, a and Cn are
defined by the second through holes TH2. In more detail, the solar
cell apparatus according to the embodiment is divided into the
cells C1, C2, In and Cn by the second through holes TH2. In
addition, the cells C1, C2, In and Cn are connected to each other
in a second direction crossing a first direction. In other words,
current may flow in the second direction through the cells C1, C2,
re and Cn.
[0055] The connection parts 800 are provided at the inside of the
second through holes TH2. In addition, a portion of the connection
part 800 may be provided in the first through holes TH1. In other
words, the portion of the connection part 800 may be provided on
the insulating part 700.
[0056] Each connection part 8700 extends downward from the front
electrode layer 600 and is connected to the back electrode layer
200. In detail, the connection parts 800 make contact with the
front electrode layer 600. The connection parts 800 pass through
the light absorbing layer 300 while being connected to the back
electrode layer 200. For example, each connection part 800 extends
from a front electrode of the first cell C1 and is connected to a
back electrode of the second cell C2.
[0057] Thus, the connection parts 800 connect adjacent cells to
each other. In more detail, the connection parts 800 connect front
electrodes and back electrodes included in adjacent C1, C2, on and
Cn to each other.
[0058] The connection part 800 includes a material different from
that of the front electrode layer 600. In detail, the connection
part 800 may include metal. For example, the connection part 800
may include aluminum (Al), nickel (Ni), or silver (Ag).
[0059] According to the present embodiment, a dead zone may be
reduced by the second and third through holes TH2 and TH3.
Accordingly, the density of short current can be improved, so that
the photo-electric conversion efficiency can be improved.
[0060] In addition, as described above, the first to third through
holes TH1, TH2, and TH3 are formed after performing a deposition
process up to the front electrode layer 600. In other words, after
a thin film deposition process has been finished, the first to
third through holes TH1 to TH3 are formed at once, so that the
process time and the cost can be reduced. In addition, since the
first to third through holes TH1 to TH3 are formed after the thin
film deposition process has been finished, the oxidation of the
back electrode layer 200 and the front electrode layer 600 can be
minimized. According, the contact resistance and the serial
resistance can be reduced, and the fill factor can be increased. In
other words, according to the related art, the first through holes
TH1 are formed during the deposition process, and the stand-by time
for a process is increased, so that the contact resistance is
increased due to the oxidation of the back electrode layer 200 and
the front electrode layer 600.
[0061] Hereinafter, a solar cell apparatus according to the second
embodiment will be described with reference to FIG. 3. For the
clear and brief explanation, the detail of the components the same
as or similar to those of the first embodiment will be omitted in
order to avoid redundancy.
[0062] FIG. 3 is a sectional view showing the panel of a solar cell
apparatus according to the second embodiment.
[0063] Referring to FIG. 3, the second through holes (reference
numeral TH2 of FIG. 2) and the third through holes (reference
numeral TH3 of FIG. 2) according to the first embodiment are
overlapped with each other to form second through holes th2. The
connection part 800 may be provided in a portion of the second
through holes th2.
[0064] Hereinafter, a method of fabricating the solar cell
apparatus according to the first embodiment will be described with
reference to FIGS. 4 to 8. FIGS. 4 to 8 are sectional views showing
the fabricating process of the panel of the solar cell apparatus
according to the first embodiment.
[0065] First, referring to FIG. 4, the back electrode layer 200 is
formed on the support substrate 100. The back electrode layer 200
may include molybdenum (Mo). The back electrode layer 200 may be
formed with at least two layers through processes different from
each other.
[0066] A step of forming the light absorbing layer 300 on the back
electrode layer 200 is performed. The light absorbing layer 300 may
be formed through a sputtering process or an evaporation
scheme.
[0067] For example, in order to form the light absorbing layer 300,
various schemes such as a scheme of forming a Cu(In,Ga)Se2 (CIGS)
based-light absorbing layer 300 by simultaneously or separately
evaporating Cu, In, Ga, and Se and a scheme of performing a
selenization process after forming a metallic precursor film have
been extensively performed.
[0068] Regarding the details of the selenization process after
forming the metallic precursor layer, the metallic precursor layer
is formed on the back contact electrode 200 through a sputtering
process employing a Cu target, an In target, or a Ga target.
[0069] Thereafter, the metallic precursor layer is subject to the
selenization process so that the Cu(In,Ga)Se2 (CIGS) based-light
absorbing layer 300 is formed.
[0070] In addition, the sputtering process employing the Cu target,
the In target, and the Ga target and the selenization process may
be simultaneously performed.
[0071] In addition, a CIS or a CIG light absorbing layer 300 may be
formed through a sputtering process employing only Cu and In
targets or only Cu and Ga targets and the selenization process.
[0072] Thereafter, the buffer layer 400 may be formed after
depositing CdS through a sputtering process or a CBD (chemical bath
deposition) scheme.
[0073] Thereafter, the high resistance buffer layer 500 is formed
by depositing zinc oxide on the buffer layer 400 through a
sputtering process.
[0074] The buffer layer 400 and the high resistance buffer layer
500 are deposited at a low thickness. For example, the thicknesses
of the buffer layer 400 and the high resistance buffer layer 500
may be in the range of about 1 nm to about 80 nm.
[0075] A step of forming the front electrode layer 600 on the high
resistance buffer layer 500 is performed. The front electrode layer
600 may be formed by depositing a transparent conductive material
such as Al doped zinc oxide (AZO) on the high resistance buffer
layer 500 through a sputtering process.
[0076] Thereafter, referring to FIG. 5, a step of forming the first
through holes TH1 passing through the back electrode layer 200, the
light absorbing layer 300, the buffer layer 400, and the front
electrode layer 600 is performed. The first through holes TH1 may
be formed by a mechanical device such a tip. In other words, the
back electrode layer 200, the light absorbing layer 300, the buffer
layer 400, and the front electrode layer 600 may be mechanically
patterned by a tip. The width of the tip may be in the range of
about 40 .mu.m to about 180 .mu.m.
[0077] Subsequently, referring to FIG. 6, a step of forming the
second through holes TH2 passing through the light absorbing layer
300, the buffer layer 400, and the front electrode layer 600 is
performed after the forming the front electrode layer 600. The
second through holes TH2 may be formed adjacent to the first
through holes TH1. The second through holes TH2 may be patterned by
a laser.
[0078] Thereafter, referring to FIG. 7, the third through holes TH3
may be formed beside the second through holes TH2 to expose the top
surface 210 for the back electrode layer 200 while passing through
the light absorbing layer 300. The third through holes TH3 may be
patterned by a laser.
[0079] Thereafter, referring to FIG. 8, the insulating part 700 may
be formed in the first through holes TH1. The top surface 710 of
the insulating part 700 may be formed higher than the top surface
210 of the back electrode layer 200. The insulating part 700 may be
formed by inserting an insulating material including polymer or a
ceramic material into the first through holes TH1 through a screen
printing scheme or a dispenser. Thereafter, a binder may be removed
from the insulating material by curing the insulating material.
[0080] Thereafter, referring to FIG. 2, the connection part 800 may
be formed on the top surface of the insulating part 700 and formed
in the second through holes TH2. In the step of forming the
connection part 800, metallic paste formed by mixing metal and an
organic binder may be inserted into the second through holes TH2.
The metallic paste may be inserted through a screen printing scheme
or a dispenser.
[0081] Thereafter, a step of curing the metallic paste is
performed. The step of curing the metallic paste may be performed
at the temperature of 250.degree. C. or less. In addition, the step
of curing the metallic paste may be performed for 30 minutes or
less. Through the step of curing the metallic paste, the binder may
be removed from the metallic paste.
[0082] The dead zone can be reduced through the second and third
through holes TH2 and TH3. Accordingly, the density of short
current can be improved, so that the photo-electric conversion
efficiency can be improved.
[0083] In addition, after the thin film deposition process has been
finished, since the first to third through holes TH1 to TH3 are
patterned after the support substrate 100 has been completely
heat-distorted, the application of the offset value is not
required.
[0084] Hereinafter, the method of fabricating the solar cell
apparatus according to the second embodiment will be described with
reference to FIGS. 9 to 11.
[0085] FIGS. 9 to 11 are sectional views showing the fabricating
process of the panel of the solar cell apparatus according to the
second embodiment.
[0086] Referring to FIG. 9, a step of forming the first through
holes th1 passing through the back electrode layer 200, the light
absorbing layer 300, the buffer layer 400, and the front electrode
layer 600 is performed.
[0087] Thereafter, referring to FIG. 10, a step of forming the
second through holes th2 beside the first through holes till is
performed. The second through holes th2 may pass through the light
absorbing layer 300, the buffer layer 400, and the front electrode
layer 600.
[0088] Then, referring to FIG. 11, the insulating part 700 may be
formed in the first through holes th1. Subsequently, referring to
FIG. 3, the connection part 800 may be formed on the top surface
710 of the insulating part 700 and formed in a portion of the
second through holes th2.
[0089] Any reference in this specification to through holes th2.art
through holes 1 of the solar cell app., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the
invention. The appearances of such phrases in various places in the
specification are not necessarily all referring to the same
embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with any embodiment, it
is submitted that it is within the purview of one skilled in the
art to effect such feature, structure, or characteristic in
connection with other ones of the embodiments.
[0090] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
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