U.S. patent application number 14/077041 was filed with the patent office on 2014-03-06 for gas injection device and solar cell manufacturing method using the same.
This patent application is currently assigned to Samsung Display Co., Ltd.. The applicant listed for this patent is Samsung Display Co., Ltd., Samsung SDI Co., Ltd.. Invention is credited to Seong-Ryong Hwang, In-Ki Kim, Woo-Su Lee, Jung-Gyu Nam, Sang-Cheol Park, Seoung-Jin Seo.
Application Number | 20140061338 14/077041 |
Document ID | / |
Family ID | 45934491 |
Filed Date | 2014-03-06 |
United States Patent
Application |
20140061338 |
Kind Code |
A1 |
Seo; Seoung-Jin ; et
al. |
March 6, 2014 |
GAS INJECTION DEVICE AND SOLAR CELL MANUFACTURING METHOD USING THE
SAME
Abstract
A solar cell manufacturing method includes forming a first
electrode on a substrate, forming a mixed metal layer on the first
electrode, forming a light absorbing layer by injecting hydrogen
selenide on the entire surface of the mixed metal layer using a gas
injection device, and forming a second electrode on the light
absorbing layer. Further, the gas injection device includes a gas
pipeline, an inner gas pipe positioned in the gas pipeline and
having an opening, and a plurality of injection nozzles disposed
below the gas pipeline.
Inventors: |
Seo; Seoung-Jin; (Yongin-si,
KR) ; Nam; Jung-Gyu; (Yongin-si, KR) ; Park;
Sang-Cheol; (Yongin-si, KR) ; Lee; Woo-Su;
(Yongin-si, KR) ; Hwang; Seong-Ryong; (Yongin-si,
KR) ; Kim; In-Ki; (Yongin-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Display Co., Ltd.
Samsung SDI Co., Ltd. |
Yongin-si
Yongin-si |
|
KR
KR |
|
|
Assignee: |
Samsung Display Co., Ltd.
Yongin-si
KR
Samsung SDI Co., Ltd.
Yongin-si
KR
|
Family ID: |
45934491 |
Appl. No.: |
14/077041 |
Filed: |
November 11, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13271276 |
Oct 12, 2011 |
8586401 |
|
|
14077041 |
|
|
|
|
Current U.S.
Class: |
239/548 |
Current CPC
Class: |
Y02E 10/541 20130101;
H01L 31/0749 20130101; Y02P 70/50 20151101; H01L 21/18 20130101;
Y02P 70/521 20151101; H01L 31/0322 20130101 |
Class at
Publication: |
239/548 |
International
Class: |
H01L 21/18 20060101
H01L021/18 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 14, 2010 |
KR |
10-2010-0100183 |
Claims
1. A gas injection device, comprising: a gas pipeline, an inner gas
pipe within the gas pipeline, and including an opening extended
through a wall of the inner gas pipe and disposed between opposing
longitudinal ends of the inner gas pipe, and a plurality of
injection nozzles disposed below the gas pipeline.
2. The device of claim 1, wherein: a cross-section of the inner gas
pipe includes a first portion of the wall separated from a second
portion of the wall, and the opening of the inner gas pipe is
formed in the first portion of the wall opposite to the injection
nozzles with respect to the second portion of the wall.
3. The device of claim 2, wherein: the opening has a planar
quadrangle shape, a length of the opening in a longitudinal
direction of the inner gas pipe is about 20% to about 30% of an
interval between a first injection nozzle adjacent to an inlet of
the gas injection device, and a last injection nozzle furthest away
from the inlet, and a width of the opening taken perpendicular to
the longitudinal direction of the inner gas pipe is about 40% to
about 45% of a diameter of the inner gas pipe.
4. The device of claim 3, wherein: the opening is positioned apart
from the first injection nozzle and in a direction towards the last
injection nozzle by about 40% to about 45% of the interval between
the first injection nozzle and the last injection nozzle.
5. The device of claim 4, wherein: the diameter of the inner gas
pipe is half of a diameter of the gas pipeline.
6. The device of claim 5, wherein: both of the longitudinal ends of
the inner gas pipe are opened.
7. The device of claim 6, wherein: the longitudinal direction of
the inner gas pipe is parallel to an arrangement direction of the
injection nozzles.
8. The device of claim 7, wherein: the plurality of injection
nozzles have a same diameter and are disposed at regular intervals.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/271,276, filed Oct. 12, 2011, which claims priority to
and the benefit of Korean Patent Application No. 10-2010-0100183,
filed Oct. 14, 2010, the entire content of both of which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field
[0003] The present invention relates to a gas injection device and
a solar cell manufacturing method using the same.
[0004] 2. Related Art
[0005] Solar cells convert sunlight energy into electrical energy.
Solar cells are important clean energy or next-generation energy
that replaces fossil energy which causes a greenhouse effect due to
discharge of carbon dioxide (CO.sub.2) and replaces nuclear energy
which contaminates an earth environment such as air pollution due
to radioactive waste.
[0006] The solar cells basically generate electricity using two
kinds of semiconductors such as a P-type semiconductor and an
N-type semiconductor. When the solar cells are used as a light
absorbing layer, they are classified into various kinds depending
on materials used therein.
[0007] The solar cell has a general structure in which a front
transparent conductive layer, a P-N layer, and a rear reflecting
electrode layer are deposited on a substrate in sequence. When
sunlight is incident to the solar cell of the structure, electrons
are collected on the N layer and holes are collected on the P
layer, to thereby generate electric current.
[0008] A compound solar cell (copper-indium-gallium-selenide,
"CIGS") has high efficiency to convert sunlight into electricity
without using silicon unlike known silicon based solar cells. The
CIGS may be formed by depositing copper (Cu), indium (In), gallium
(Ga) and selenium (Se) compounds on an electrode formed on flexible
substrates such as stainless, aluminum, etc., as well as a glass
substrate.
[0009] In a conventional solar cell, a CIGS (Cu, In, Ga, Se)
compound layer may be formed by injecting hydrogen selenide
(H.sub.2Se) on a mixed layer of copper (Cu), indium (In), and
gallium (Ga) after the mixed layer of copper (Cu), indium (In), and
gallium (Ga) is formed.
[0010] In a conventional method of forming the solar cell, the
hydrogen selenide (H.sub.2Se) may be injected through a gas
pipeline in a gas injection device. As area of the solar cell
becomes larger, the injecting area of the hydrogen selenide
(H.sub.2Se) becomes larger, and the length of the gas pipeline also
becomes longer. As the length of the gas pipeline becomes longer,
the number of nozzles attached to the gas pipeline is also
increased, such that difference of discharge rate of nozzles
disposed between an inlet and an outlet of the gas pipeline is
generated because pressure is decreased due to channel friction
loss in the gas pipeline and discharge rate through the nozzles.
Accordingly, since the injecting amount of the hydrogen selenide
(H.sub.2Se) is not uniform in the conventional method of forming
the solar cell, the CIGS (Cu, In, Ga, Se) compound layer is not
uniform.
[0011] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention, and therefore contains information that does not form
any part of the prior art.
SUMMARY
[0012] The present invention has been made in an effort to provide
a uniform copper-indium-gallium-selenide ("CIGS") compound layer in
manufacturing process of a solar cell having a large area.
[0013] An exemplary embodiment of the present invention provides a
solar cell manufacturing method including forming a first electrode
on a substrate, forming a mixed metal layer on the first electrode,
forming a light absorbing layer by injecting hydrogen selenide
(H.sub.2Se) on an entire surface of the mixed metal layer using a
gas injection device, and forming a second electrode on the light
absorbing layer. The gas injection device includes a gas pipeline,
an inner gas pipe positioned in the gas pipeline and a plurality of
injection nozzles disposed below the gas pipeline. The inner gas
pipe includes an opening extended through a wall of the inner gas
pipe, and is disposed between opposing longitudinal ends of the
inner gas pipe.
[0014] In an embodiment, a cross-section of the inner gas pipe
includes a first portion of the wall separated from a second
portion of the wall. The opening may be formed in the first portion
of the wall opposite to the injection nozzles with respect to the
second portion of the wall.
[0015] In an embodiment, the opening may have a quadrangle shape, a
length of the opening may be about 20% to about 30% of an interval
between a first injection nozzle adjacent to an inlet of the gas
injection device and a last injection nozzle furthest away from the
inlet. A width of the opening may be about 40% to about 45% of a
diameter of the inner gas pipe.
[0016] In an embodiment, the opening may be positioned apart from
the first injection nozzle and in a direction towards the last
injection nozzle by about 40% to about 45% of the interval between
the first injection nozzle and the last injection nozzle.
[0017] In an embodiment, the diameter of the inner gas pipe may be
half of a diameter of the gas pipeline.
[0018] In an embodiment, both of the longitudinal ends of the inner
gas pipe may be opened.
[0019] In an embodiment, the longitudinal direction of the inner
gas pipe may be parallel to an arrangement direction of the
injection nozzles.
[0020] In an embodiment, the plurality of injection nozzles may
have a same diameter and be disposed at regular intervals in a
longitudinal direction of the gas pipeline.
[0021] In an embodiment, the mixed metal layer may be made of
copper, indium and gallium.
[0022] In an embodiment, the forming a light absorbing layer may
further include performing a heat treatment using hydrogen selenide
(H.sub.2Se) at about 500 degrees Celsius (.degree. C.) to about
600.degree. C.
[0023] In an embodiment, the first electrode may be made of
reflective conductive metal and the second electrode may be made of
transparent conductive metal.
[0024] In an embodiment, the method may further include forming a
buffer layer between the light absorbing layer and the second
electrode.
[0025] An exemplary embodiment of the present invention provides a
gas injection device including a gas pipeline, an inner gas pipe
within the gas pipeline, and including an opening extended through
a wall of the inner gas pipe and disposed between opposing
longitudinal ends of the inner gas pipe, and a plurality of
injection nozzles disposed below the gas pipeline.
[0026] According to exemplary embodiments of the present invention,
a CIGS compound layer is uniformly formed in a solar cell having a
large area, by uniformly injecting hydrogen selenide (H.sub.2Se),
using a gas injection device including an inner gas pipe having an
opening which is formed in a gas pipeline within the gas pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and other aspects, advantages and features of this
disclosure will become more apparent by describing in further
detail exemplary embodiments thereof with reference to the
accompanying drawings, in which:
[0028] FIG. 1 is a cross sectional view of an exemplary embodiment
of a solar cell, according to the present invention.
[0029] FIGS. 2 to 4 are diagrams showing an exemplary embodiment of
a method of manufacturing the solar cell of FIG. 1.
[0030] FIG. 5 is a perspective view schematically showing an
exemplary embodiment of an electric furnace, according to the
present invention.
[0031] FIG. 6 is a front cross-sectional view of an exemplary
embodiment of a gas injection device, according to the present
invention.
[0032] FIG. 7 is a side cross-sectional view of the exemplary
embodiment of a gas injection device, according to the present
invention.
[0033] FIG. 8 is a plan view of the exemplary embodiment of a gas
injection device, according to the present invention.
DETAILED DESCRIPTION
[0034] The present invention will be described more fully
hereinafter with reference to the accompanying drawings, in which
exemplary embodiments of the invention are shown. As those skilled
in the art would realize, the described embodiments may be modified
in various different ways, all without departing from the spirit or
scope of the present invention. On the contrary, the embodiments
introduced herein are provided to fully understand the disclosed
contents and fully transfer the spirit of the present invention to
those skilled in the art.
[0035] In the drawings, the thickness of layers, films, panels,
regions, etc., are exaggerated for clarity. When a layer is
referred to as being "on" another layer or a substrate, it can be
directly on another layer or the substrate, or an intervening layer
may also be present. In contrast, when an element is referred to as
being "directly on" another element or layer, there are no
intervening elements or layers present. Throughout the
specification, like reference numerals refer to like elements. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items.
[0036] It will be understood that, although the terms first,
second, third, etc., may be used herein to describe various
elements, components, regions, layers and/or sections, these
elements, components, regions, layers and/or sections should not be
limited by these terms. These terms are only used to distinguish
one element, component, region, layer or section from another
region, layer or section. Thus, a first element, component, region,
layer or section discussed below could be termed a second element,
component, region, layer or section without departing from the
teachings of the invention.
[0037] Spatially relative terms, such as "below," "lower," "under,"
"upper" and the like, may be used herein for ease of description to
describe the relationship of one element or feature to another
element(s) or feature(s) as illustrated in the figures. It will be
understood that the spatially relative terms are intended to
encompass different orientations of the device in use or operation,
in addition to the orientation depicted in the figures. For
example, if the device in the figures is turned over, elements
described as "below" relative to other elements or features would
then be oriented "above" relative to the other elements or
features. Thus, the exemplary term "below" can encompass both an
orientation of above and below. The device may be otherwise
oriented (rotated 90 degrees or at other orientations) and the
spatially relative descriptors used herein interpreted
accordingly.
[0038] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a," "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
[0039] Embodiments of the invention are described herein with
reference to cross-section illustrations that are schematic
illustrations of idealized embodiments (and intermediate
structures) of the invention. As such, variations from the shapes
of the illustrations as a result, for example, of manufacturing
techniques and/or tolerances, are to be expected. Thus, embodiments
of the invention should not be construed as limited to the
particular shapes of regions illustrated herein but are to include
deviations in shapes that result, for example, from
manufacturing.
[0040] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. It will be further understood that terms, such
as those defined in commonly used dictionaries, should be
interpreted as having a meaning that is consistent with their
meaning in the context of the relevant art and will not be
interpreted in an idealized or overly formal sense unless expressly
so defined herein.
[0041] All methods described herein can be performed in a suitable
order unless otherwise indicated herein or otherwise clearly
contradicted by context. The use of any and all examples, or
exemplary language (e.g., "such as"), is intended merely to better
illustrate the invention and does not pose a limitation on the
scope of the invention unless otherwise claimed. No language in the
specification should be construed as indicating any non-claimed
element as essential to the practice of the invention as used
herein.
[0042] Hereinafter, the invention will be described in detail with
reference to the accompanying drawings.
[0043] FIG. 1 is a cross sectional view of an exemplary embodiment
of a solar cell, according to the present invention.
[0044] Referring to FIG. 1, the solar cell of the exemplary
embodiment of the present invention includes a first electrode 110
directly on a first substrate 100. The first electrode 110 includes
a reflective conductive metal such as molybdenum (Mo), aluminum
(Al), or copper (Cu).
[0045] A light absorbing layer 120 and a buffer layer 130 are
directly on the first electrode 110 in sequence. The light
absorbing layer 120 includes a copper-indium-gallium-selenide
("CIGS"), for example CuInGaSe.sub.2, compound and functions as a
P-type semiconductor actually absorbing light.
[0046] The buffer layer 130 is between P-N junctions to reduce a
difference in lattice constant and an energy band gap between a
P-type semiconductor and an N-type semiconductor. Accordingly, an
energy band value of a material used as the buffer layer 130 may be
a middle value of the energy band gap between the P-type
semiconductor and the N-type semiconductor. The buffer layer 130
includes CdS, Zn(O,S,OH), In(OH)xSy, ZnInxSey, ZnSe, and the
like.
[0047] A second electrode 210 is directly on the buffer layer 130.
The second electrode 210 includes a transparent conductive material
as an N-type semiconductor. The second electrode 210 includes
ZnO:Al. An upper surface of the second electrode 210 is textured
(e.g., non-linear) in order to increase an effective light quantity
absorbed in the solar cell, by reducing light reflection on the
surface of the solar cell.
[0048] A second substrate 200 is directly on the upper surface of
the second electrode 210.
[0049] Hereinafter, referring to FIGS. 2 to 4, an exemplary
embodiment of a method of manufacturing the solar cell shown in
FIG. 1 will be described.
[0050] FIGS. 2 to 4 are cross-sectional views sequentially
illustrating the exemplary embodiment of a method of manufacturing
the solar cell of FIG. 1.
[0051] As shown in FIGS. 2 to 4, the first electrode 110 is formed
by depositing a reflective conductive metal such as molybdenum,
aluminum or copper directly on the first substrate 100. A mixed
metal layer 121 formed by mixing copper (Cu), indium (In), and
gallium (Ga) is subsequently formed directly on the formed first
electrode 110.
[0052] Thereafter, a high-temperature heat treatment is performed
by applying hydrogen selenide (H2Se) directly on an entire upper
surface of the mixed metal layer 121, at about 500 degrees Celsius
(.degree. C.) to about 600.degree. C. The entire of the upper
surface is considered as a "large" area in the solar cell of FIG.
1. In the illustrated embodiment, the hydrogen selenide (H2Se) is
injected on the entire surface of the mixed metal layer 121 using a
gas injection device 300.
[0053] The gas injection device 300 includes a gas pipeline 310 and
a plurality of an injection nozzle 320 disposed below the gas
pipeline 310, between the gas pipeline 310 and the mixed metal
layer 121. The plurality of injection nozzles 320 are disposed at
regular intervals and have substantially a same diameter.
[0054] The hydrogen selenide (H2Se) which initially flows into the
gas pipeline 310 is injected on the entire surface of the mixed
metal layer 121 through the plurality of injection nozzles 320, and
is injected from the plurality of injection nozzles 320 with a
nearly constant amount from each of the nozzles 320.
[0055] When the high-temperature heat treatment is performed by the
hydrogen selenide (H.sub.2Se), the light absorbing layer 120 is
formed by mixing selenium in the mixed metal layer 121, as shown in
FIG. 4. The light absorbing layer 120 includes the CIGS compound
and functions as a P-type semiconductor actually absorbing
light.
[0056] As shown in FIG. 1, the buffer layer 130 is formed by
depositing any one of CdS, Zn(O,S,OH), In(OH)xSy, ZnInxSey, and
ZnSe directly on the formed light absorbing layer 120. The second
electrode 210 is formed directly on formed the buffer layer 130.
The second electrode 210 as the N-type semiconductor is made of a
transparent conductive material, e.g., ZnO:Al. In the forming of
the second electrode 210 including the transparent conductive
material, texturing for forming an unevenness may be performed by
etching an upper surface of the second electrode 210. The texturing
of the upper surface of the second electrode 210 is performed in
order to increase an effective light quantity absorbed in the solar
cell by reducing light reflection on the surface of the solar
cell.
[0057] Thereafter, the second substrate 200 is formed directly on
the second electrode 210 to complete the solar cell of FIG. 1.
[0058] As described above, the CIGS compound layer (e.g., the light
absorbing 120) is uniformly formed in the solar cell having a large
area by uniformly injecting the hydrogen selenide (H.sub.2Se) from
the plurality of injection nozzles 320 disposed at regular
intervals and having substantially the same diameter, and by
performing the high-temperature heat treatment on the entire
surface of the mixed metal layer 121 after the mixed metal layer
121 of copper, gallium, and indium is formed.
[0059] A solar cell including the light absorbing layer 120 is
formed by injecting hydrogen selenide (H.sub.2Se) from the gas
injection device 300 in a manufacturing process of the solar cell.
The light absorbing layer 120 of a final solar cell having a
uniform material application and uniform structure (e.g.,
dimensional thickness, etc.) is considered a structural
characteristic of the final solar cell. Since the uniform light
absorbing layer 120 is imparted by injecting the hydrogen selenide
(H.sub.2Se) using a plurality of injection nozzles 320 disposed at
regular intervals and having substantially the same diameter, and
is imparted by injecting the hydrogen selenide (H.sub.2Se) over an
entire surface of the base mixed metal layer 121 of the light
absorbing layer 120, such process using the plurality of injection
nozzles 320 disposed at regular intervals and having substantially
the same diameter, and such process injecting the hydrogen selenide
(H.sub.2Se) over an entire surface of the base mixed metal layer
121, is considered to impart the distinct structural characteristic
of the uniform light absorbing layer 120.
[0060] Hereinafter, referring to FIGS. 5 to 8, an exemplary
embodiment of a gas injection device, according to the present
invention, will be described.
[0061] FIG. 5 is a perspective view schematically showing an
exemplary embodiment of an electric furnace, according to the
present invention.
[0062] As shown in FIG. 5, a plurality of gas injection devices 300
are positioned in an electric furnace 400 and connected to a gas
inlet 350. Hydrogen selenide (H.sub.2Se) is supplied to the gas
inlet 350. A support 450 on which a target is injected with the
hydrogen selenide (H.sub.2Se) from the gas injection devices 300,
is below the gas injection device 300.
[0063] FIG. 6 is a front cross-sectional view of an exemplary
embodiment of a gas injection device according to the present
invention, FIG. 7 is a side cross-sectional view of the exemplary
embodiment of a gas injection device according to the present
invention, and FIG. 8 is a plan view of the exemplary embodiment of
a gas injection device according to the present invention.
[0064] As shown in FIGS. 6 to 8, the gas injection device 300 of
the illustrated exemplary embodiment includes a gas pipeline 310
and a plurality of injection nozzles 320.
[0065] The plurality of injection nozzles 320 are disposed below
the gas pipeline 310. The plurality of injection nozzles 320 are
attached at a predetermined location of the gas pipeline 310 and
longitudinally extended from the gas pipeline 310 in three
different directions. An inner gas pipe 311 having an opening 312
is positioned in the gas pipeline 310. A first injection nozzle is
adjacent to an inlet of the gas injection device, and a last
injection nozzle is furthest away from the inlet.
[0066] The plurality of injection nozzles 320 are disposed at
regular intervals and have a same diameter. The regular intervals
may be along a longitudinal direction of the gas pipeline 310
and/or along a circumference of the gas pipeline 310. The diameter
may be taken as an inner or outer diameter at a distal end of an
injection nozzle 320, or may be taken at a same point along the
longitudinal direction of the extended nozzle 320. An end of the
inner gas pipe 311 within the gas pipeline 310 is not closed, as
illustrated at the right side of FIG. 7. The inner gas pipe 311 is
extended in a longitudinal direction which is parallel to an
arrangement direction of the injection nozzles 320 along the gas
pipeline 310, for example, a horizontal direction of FIG. 7.
[0067] The inner gas pipe 311 includes walls open at an end of the
inner gas pipe 311, and may include an upper wall and a lower wall
with a channel defined therebetween, in the cross-sectional view of
FIG. 7. The lower wall is between the channel and the plurality of
injection nozzles 320.
[0068] The opening 312 of the inner gas pipe 311 is formed in the
upper wall, which is opposite to the injection nozzles 320 with
respect to the channel. The opening 312 is extended completely
through a thickness of the wall of the inner gas pipe 311, such
that the wall of the inner gas pipe solely defines the opening
312.
[0069] A diameter D2 of the inner gas pipe 311 is a about half of a
diameter D1 of the gas pipeline 310. The walls of the inner gas
pipe 311 are completely within walls and spaced apart from walls of
the gas pipeline 310, as illustrated in FIGS. 6-8.
[0070] The opening 312 has a quadrangle shape in a plan view of the
inner gas pipe 311, as illustrated in FIG. 8. A length (X) of the
opening 312 in a longitudinal direction of the inner gas pipe 311
is about 20% to about 30% of an interval between a first injection
nozzle adjacent to the gas inlet 350, and a last injection nozzle
furthest from the gas inlet 350. A width (Y) of the opening 312 in
a direction perpendicular to the longitudinal direction of the
inner gas pipe 311 is about 40% to about 45% of the diameter D2 of
the inner gas pipe 311. In the illustrated exemplary embodiment of
the present invention, the opening 312 is the quadrangle shape, but
the planar shape of the opening 312 is not limited thereto and may
have various shapes.
[0071] The opening 312 is positioned apart from the first injection
nozzle and in a direction towards the last injection nozzle, by
about 40% to about 45% of the interval between the first injection
nozzle and the last injection nozzle.
[0072] The hydrogen selenide (H.sub.2Se) which flows into the gas
pipeline 310 moves to within walls of the inner gas pipe 311, and
moves to outside of the wall of the inner gas pipe 311 (indicated
by the various arrows in FIG. 7), and is mixed in the end of the
inner gas pipe 311 and finally injected through the injection
nozzles 320. The opening 312 formed in the inner gas pipe 311
reduces a pressure difference between both ends of the gas pipeline
310.
[0073] That is, since the inner gas pipe 311 is disposed in the gas
pipeline 310 and includes the opening 312 is disposed in the inner
gas pipe 311, a part of a total pressure within the gas pipeline
310 is compensated, thereby reducing the pressure difference
between both of opposing ends of the gas pipeline 310. Therefore,
the hydrogen selenide (H2Se) is injected through the plurality of
injection nozzles 320 in a substantially same amount from each of
the nozzles 320.
[0074] A solar cell including the light absorbing layer 120 is
formed by injecting hydrogen selenide (H.sub.2Se) from the gas
injection device 300 in a manufacturing process of the solar cell.
The light absorbing layer 120 of a final solar cell having a
uniform material application and uniform structure (e.g.,
dimensional thickness, etc.) is considered a structural
characteristic of the final solar cell. Since the uniform light
absorbing layer 120 is imparted by injecting the hydrogen selenide
(H.sub.2Se) using the inner gas pipe 311 disposed in the gas
pipeline 310 and including the opening 312 disposed in the inner
gas pipe 311, to reduce the pressure difference between both of
opposing ends of the gas pipeline 310 and to inject a substantially
same amount of hydrogen selenide (H.sub.2Se) from each of the
nozzles 320, such process using the inner gas pipe 311 disposed in
the gas pipeline 310 and including the opening 312 is considered to
impart the distinct structural characteristic of the uniform light
absorbing layer 120.
[0075] While this invention has been described in connection with
what is presently considered to be practical exemplary embodiments,
it is to be understood that the invention is not limited to the
disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims.
* * * * *