US20140109963A1 - Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell - Google Patents

Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell Download PDF

Info

Publication number
US20140109963A1
US20140109963A1 US14/135,621 US201314135621A US2014109963A1 US 20140109963 A1 US20140109963 A1 US 20140109963A1 US 201314135621 A US201314135621 A US 201314135621A US 2014109963 A1 US2014109963 A1 US 2014109963A1
Authority
US
United States
Prior art keywords
thin film
solar cell
single junction
layer
film solar
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/135,621
Inventor
Yong-Duck Chung
Won Seok Han
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electronics and Telecommunications Research Institute ETRI
Original Assignee
Electronics and Telecommunications Research Institute ETRI
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Electronics and Telecommunications Research Institute ETRI filed Critical Electronics and Telecommunications Research Institute ETRI
Priority to US14/135,621 priority Critical patent/US20140109963A1/en
Assigned to ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE reassignment ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CHUNG, YONG-DUCK, HAN, WON SEOK
Publication of US20140109963A1 publication Critical patent/US20140109963A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
    • H01L31/0264—Inorganic materials
    • H01L31/032—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
    • H01L31/0322—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312 comprising only AIBIIICVI chalcopyrite compounds, e.g. Cu In Se2, Cu Ga Se2, Cu In Ga Se2
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0216—Coatings
    • H01L31/02161—Coatings for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/02167—Coatings for devices characterised by at least one potential jump barrier or surface barrier for solar cells
    • H01L31/02168—Coatings for devices characterised by at least one potential jump barrier or surface barrier for solar cells the coatings being antireflective or having enhancing optical properties for the solar cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/036—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes
    • H01L31/0392—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including thin films deposited on metallic or insulating substrates ; characterised by specific substrate materials or substrate features or by the presence of intermediate layers, e.g. barrier layers, on the substrate
    • H01L31/03923—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including thin films deposited on metallic or insulating substrates ; characterised by specific substrate materials or substrate features or by the presence of intermediate layers, e.g. barrier layers, on the substrate including AIBIIICVI compound materials, e.g. CIS, CIGS
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
    • H01L31/068—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/541—CuInSe2 material PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/547—Monocrystalline silicon PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to a single junction type CIGS (Cu (In, Ga) Se 2 ) thin film solar cell and a method for manufacturing the single junction type CIGS thin film solar cell, and more particularly, to a single junction type CIGS thin film solar cell including a CIGS light absorption layer manufactured using a single junction, and a method for manufacturing the single junction type CIGS thin film solar cell.
  • CIGS Cu (In, Ga) Se 2
  • Solar cells which absorb sunlight to convert it to electricity, are classified into solar heat cells that use solar heat to generate steam for rotating a turbine, and photovoltaic cells that use the nature of a semiconductor to convert the energy of sunlight into electrical energy.
  • solar cells are referred to as photovoltaic cells (hereinafter, solar cells).
  • Embodiments of the present invention are directed to a single junction type CIGS thin film solar cell including a single junction CIGS light absorption layer having a P type CIGS semiconductor layer and an N type CIGS semiconductor layer, and a method for manufacturing the single junction type CIGS thin film solar cell.
  • Embodiments of the present invention are also directed to a single junction type CIGS thin film solar cell that includes a light absorption layer having a P type CIGS layer and an N type CIGS layer coupled to the P type CIGS layer to form a single junction, and a method for manufacturing the single junction type CIGS thin film solar cell, which make it possible to prevent surface and interface contamination due to a buffer layer and environmental pollutions due to a toxic element, and to improve the performance of the solar cell.
  • a single junction type CIGS (Cu (In, Ga) Se 2 ) thin film solar cell includes: a substrate; a back contact disposed on the substrate; a light absorption layer disposed on the back contact and comprising a single junction diode comprising a CIGS thin film; and a reflection prevention film disposed on the light absorption layer.
  • the light absorption layer may include: a P type CIGS layer disposed on the back contact; and an N type CIGS layer disposed on the P type CIGS layer using a single junction.
  • the single junction type CIGS thin film solar cell may further include a window layer disposed on the N type CIGS layer between the light absorption layer and the reflection prevention film.
  • a method for manufacturing a single junction type CIGS (Cu (In, Ga) Se 2 ) thin film solar cell includes: preparing a substrate; depositing a back contact of molybdenum (Mo) on the substrate by using a sputtering method; depositing an P type CIGS layer on the back contact by using a co-evaporation method; depositing an N type CIGS layer on the P type CIGS layer; and depositing a reflection prevention film of MgF 2 on the N type CIGS layer by using an electron-beam evaporation method.
  • Mo molybdenum
  • the depositing of the N type CIGS layer may include mixing an alkali metal with a selenide, and using a co-evaporation method.
  • the alkali metal may include natrium (Na).
  • the selenide may include Na 2 Se.
  • FIG. 1 illustrates a schematic view of a single junction type CIGS thin film solar cell according to an embodiment of the present invention.
  • FIG. 2 illustrates a schematic view of a single junction type CIGS thin film solar cell according to another embodiment of the present invention.
  • FIG. 1 illustrates a schematic view of a single junction type CIGS thin film solar cell according to an embodiment of the present invention.
  • FIG. 2 illustrates a schematic view of a single junction type CIGS thin film solar cell according to another embodiment of the present invention.
  • a single junction type CIGS thin film solar cell includes a substrate 1 , a back contact 2 deposited on the substrate 1 , a light absorption layer 3 , and a reflection prevention film 4 deposited on the light absorption layer 3 .
  • the light absorption layer 3 includes a P type CIGS layer 31 and an N type CIGS layer 32 , which are coupled to each other to form a single junction and are deposited on the back contact 2 .
  • the substrate 1 is formed of sodalime glass.
  • the substrate 1 may be a ceramic substrate including alumina or quartz; a metal substrate including stainless steel, Cu tape, Cr steel, Kovar (Ni/Fe alloys), Ti, ferritic steel, or Mo; or a polymer including Kapton, Upilex, or ETH-PI.
  • the back contact 2 is formed of Mo. This is because Mo has high electrical conductivity, can be in ohmic contact with CIGS, and has high temperature stability in Se atmosphere.
  • a Mo thin film is formed using a direct current (DC) sputtering method.
  • the Mo thin film has low resistivity as an electrode, and great adhering force to the substrate 1 to prevent peeling due to a difference in thermal expansion coefficient.
  • An impurity diffusion barrier film (not shown) may be disposed between the substrate 1 and the back contact 2 .
  • the light absorption layer 3 includes the P type CIGS layer 31 and the N type CIGS layer 32 , which are coupled to each other form a single junction.
  • the P type CIGS layer 31 is formed through a CuInGaSe 2 thin film forming process, and the N type CIGS layer 32 is formed by mixing an alkali metal and a selenide.
  • CuInGaSe 2 thin film forming methods include an evaporation method as a physical method, a sputtering/selenization method, and an electroplating method as a chemical method. Each method may employ various manufacturing methods according to the type of a starting material (such as a metal or a binary compound).
  • nano-particles such as powder and colloid
  • a Mo substrate may be synthesized on a Mo substrate, and be mixed with solvent, and be processed using screen printing and reaction sintering to manufacture a light absorption layer.
  • Na as an alkali metal is mixed with Na 2 Se as a selenide to deposit the N type CIGS layer 32 using the co-evaporation method.
  • Na and Na 2 Se are used in the current embodiment, a group IA element such as K, Rb, Cs, and Fr as alkali metals having similar characteristics, and NaF, Na 2 S, or Na 2 Se may be used in another embodiment of the present Invention.
  • the reflection prevention film 4 is formed of MgF 2 using an electron-beam evaporation method as a physical thin film manufacturing method.
  • the reflection prevention film 4 reduces a reflection loss of sunlight absorbed by the solar cell to increase the efficiency of the solar cell by approximately 1%.
  • a grid electrode 5 for collecting a current on a surface of the solar cell is formed of Al or Ni/Al.
  • the grid electrode 5 is disposed at a side of the reflection prevention film 4 .
  • a window layer 6 may be deposited on the N type CIGS layer 32 between the light absorption layer 3 and the reflection prevention film 4 .
  • the window layer 6 functions as a transparent electrode on a front surface of the solar cell, the window layer 6 has high light transmissivity and high electrical conductivity.
  • a ZnO thin film used as a transparent electrode has an energy band gap of approximately 3.3 eV and a high light transmissivity of approximately 80% or greater. Furthermore, the ZnO thin film may be doped with Al or B to have a low resistance of approximately 10 -4 ⁇ cm or less. When the ZnO thin film is doped with B, light transmissivity increases in a near infrared region to increase a short circuit current.
  • the ZnO thin film may be deposited using a radio frequency (RF) sputtering method with a ZnO target, or using a reactive sputtering method with a Zn target, or using a metal organic chemical vapor deposition method.
  • RF radio frequency
  • a double structure that an indium tin oxide (ITO) thin film having excellent electro-optical characteristics is deposited on a ZnO thin film may be used.
  • ITO indium tin oxide
  • a solar cell according to an embodiment of the present invention will now be compared with a solar cell in the related art.
  • a light absorption layer of the solar cell in the related art includes only a CuInGaSe 2 thin film that is a P type semiconductor forms a PN junction with a ZnO thin film that is an N-type semiconductor and is used as a window layer.
  • the buffer layer is formed of CdS.
  • Cd is poisonous, and a wet chemical process is used for the buffer layer, unlike other thin films.
  • the P type CIGS layer 31 is coupled to the N-type CIGS layer 32 to form a single junction, the quality of the thin film is improved, and thus, the performance of the solar cell is improved.
  • CdS constituting a buffer layer is not used, environmental pollutions can be prevented.
  • the P type CIGS layer 31 is coupled to the N-type CIGS layer 32 to form the solar cell including the light absorption layer 3 in a single junction structure, and thus, surface and interface contamination due to a buffer layer and environmental pollutions due to a toxic element can be prevented, and the performance of the solar cell can be improved.

Abstract

Provided is a single junction type GIGS thin film solar cell, which includes a CIGS light absorption layer manufactured using a single junction. The single junction type GIGS thin film solar cell includes a substrate, a back contact deposited on the substrate, a light absorption layer deposited on the back contact and including a P type GIGS layer and an N type GIGS layer coupled to the P type CIGS layer using a single junction, and a reflection prevention film deposited on the light absorption layer.

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • This is a Divisional of U.S. application Ser. No. 13/207,825, filed on Aug. 11, 2011, and allowed on Sep. 25, 2013, the subject matter of which is incorporated herein by reference. The parent application Ser. No. 13/207,825 claims the benefit of Korean patent application number 10-2010-0108880, filed on Nov. 3, 2010, the disclosure of which is incorporated herein in its entirety by reference.
    • BACKGROUND OF THE INVENTION
  • The present invention relates to a single junction type CIGS (Cu (In, Ga) Se2) thin film solar cell and a method for manufacturing the single junction type CIGS thin film solar cell, and more particularly, to a single junction type CIGS thin film solar cell including a CIGS light absorption layer manufactured using a single junction, and a method for manufacturing the single junction type CIGS thin film solar cell.
  • In recent years, interest in solar cells is increasing because of energy and environmental issues.
  • Solar cells, which absorb sunlight to convert it to electricity, are classified into solar heat cells that use solar heat to generate steam for rotating a turbine, and photovoltaic cells that use the nature of a semiconductor to convert the energy of sunlight into electrical energy.
  • In general, solar cells are referred to as photovoltaic cells (hereinafter, solar cells).
  • The above description relates to the related art for clarifying the present invention, and the related art is distinct from the prior art.
    • SUMMARY OF THE INVENTION
  • Embodiments of the present invention are directed to a single junction type CIGS thin film solar cell including a single junction CIGS light absorption layer having a P type CIGS semiconductor layer and an N type CIGS semiconductor layer, and a method for manufacturing the single junction type CIGS thin film solar cell.
  • Embodiments of the present invention are also directed to a single junction type CIGS thin film solar cell that includes a light absorption layer having a P type CIGS layer and an N type CIGS layer coupled to the P type CIGS layer to form a single junction, and a method for manufacturing the single junction type CIGS thin film solar cell, which make it possible to prevent surface and interface contamination due to a buffer layer and environmental pollutions due to a toxic element, and to improve the performance of the solar cell.
  • In one embodiment, a single junction type CIGS (Cu (In, Ga) Se2) thin film solar cell includes: a substrate; a back contact disposed on the substrate; a light absorption layer disposed on the back contact and comprising a single junction diode comprising a CIGS thin film; and a reflection prevention film disposed on the light absorption layer.
  • The light absorption layer may include: a P type CIGS layer disposed on the back contact; and an N type CIGS layer disposed on the P type CIGS layer using a single junction.
  • The single junction type CIGS thin film solar cell may further include a window layer disposed on the N type CIGS layer between the light absorption layer and the reflection prevention film.
  • in another embodiment, a method for manufacturing a single junction type CIGS (Cu (In, Ga) Se2) thin film solar cell includes: preparing a substrate; depositing a back contact of molybdenum (Mo) on the substrate by using a sputtering method; depositing an P type CIGS layer on the back contact by using a co-evaporation method; depositing an N type CIGS layer on the P type CIGS layer; and depositing a reflection prevention film of MgF2 on the N type CIGS layer by using an electron-beam evaporation method.
  • The depositing of the N type CIGS layer may include mixing an alkali metal with a selenide, and using a co-evaporation method.
  • The alkali metal may include natrium (Na).
  • The selenide may include Na2Se.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 illustrates a schematic view of a single junction type CIGS thin film solar cell according to an embodiment of the present invention.
  • FIG. 2 illustrates a schematic view of a single junction type CIGS thin film solar cell according to another embodiment of the present invention.
    •  DESCRIPTION OF SPECIFIC EMBODIMENTS
  • Hereinafter, a single junction type CIGS (Cu (In, Ga) Se2) thin film solar cell and a method for manufacturing the single junction type CIGS thin film solar cell in accordance with the present invention will be described in detail with reference to the accompanying drawings.
  • Hereinafter, the present invention will be described in more detail through embodiments. The embodiments are merely for exemplifying the present invention, and the right protection scope of the present invention is not limited by the embodiments.
  • In the drawings, the thicknesses of lines or the sizes of elements may be exaggeratedly illustrated for clarity and convenience of description. Moreover, the terms used henceforth have been defined in consideration of the functions of the present invention, and may be altered according to the intent of a user or operator, or conventional practice. Therefore, the terms should be defined on the basis of the entire content of this specification.
  • FIG. 1 illustrates a schematic view of a single junction type CIGS thin film solar cell according to an embodiment of the present invention. FIG. 2 illustrates a schematic view of a single junction type CIGS thin film solar cell according to another embodiment of the present invention.
  • Referring to FIG. 1, a single junction type CIGS thin film solar cell according to an embodiment of the present invention includes a substrate 1, a back contact 2 deposited on the substrate 1, a light absorption layer 3, and a reflection prevention film 4 deposited on the light absorption layer 3. The light absorption layer 3 includes a P type CIGS layer 31 and an N type CIGS layer 32, which are coupled to each other to form a single junction and are deposited on the back contact 2.
  • The substrate 1 is formed of sodalime glass. Alternatively, the substrate 1 may be a ceramic substrate including alumina or quartz; a metal substrate including stainless steel, Cu tape, Cr steel, Kovar (Ni/Fe alloys), Ti, ferritic steel, or Mo; or a polymer including Kapton, Upilex, or ETH-PI.
  • The back contact 2 is formed of Mo. This is because Mo has high electrical conductivity, can be in ohmic contact with CIGS, and has high temperature stability in Se atmosphere.
  • A Mo thin film is formed using a direct current (DC) sputtering method. The Mo thin film has low resistivity as an electrode, and great adhering force to the substrate 1 to prevent peeling due to a difference in thermal expansion coefficient.
  • An impurity diffusion barrier film (not shown) may be disposed between the substrate 1 and the back contact 2.
  • As described above, the light absorption layer 3 includes the P type CIGS layer 31 and the N type CIGS layer 32, which are coupled to each other form a single junction.
  • The P type CIGS layer 31 is formed through a CuInGaSe2 thin film forming process, and the N type CIGS layer 32 is formed by mixing an alkali metal and a selenide.
  • CuInGaSe2 thin film forming methods include an evaporation method as a physical method, a sputtering/selenization method, and an electroplating method as a chemical method. Each method may employ various manufacturing methods according to the type of a starting material (such as a metal or a binary compound).
  • According to the current embodiment, four metal elements Cu, In, Ga, and Se are used as starting materials in a co-evaporation method. Unlike physical/chemical thin film manufacturing methods in the related art, nano-particles (such as powder and colloid) may be synthesized on a Mo substrate, and be mixed with solvent, and be processed using screen printing and reaction sintering to manufacture a light absorption layer.
  • Na as an alkali metal is mixed with Na2Se as a selenide to deposit the N type CIGS layer 32 using the co-evaporation method. Although Na and Na2Se are used in the current embodiment, a group IA element such as K, Rb, Cs, and Fr as alkali metals having similar characteristics, and NaF, Na2S, or Na2Se may be used in another embodiment of the present Invention.
  • The reflection prevention film 4 is formed of MgF2 using an electron-beam evaporation method as a physical thin film manufacturing method. The reflection prevention film 4 reduces a reflection loss of sunlight absorbed by the solar cell to increase the efficiency of the solar cell by approximately 1%.
  • A grid electrode 5 for collecting a current on a surface of the solar cell is formed of Al or Ni/Al.
  • Since the amount of absorbed sunlight is decreased by the area of the grid electrode 5, the efficiency of the solar cell may be decreased. Thus, the grid electrode 5 is disposed at a side of the reflection prevention film 4.
  • Referring to FIG. 2, a window layer 6 may be deposited on the N type CIGS layer 32 between the light absorption layer 3 and the reflection prevention film 4.
  • Since the window layer 6 functions as a transparent electrode on a front surface of the solar cell, the window layer 6 has high light transmissivity and high electrical conductivity.
  • A ZnO thin film used as a transparent electrode has an energy band gap of approximately 3.3 eV and a high light transmissivity of approximately 80% or greater. Furthermore, the ZnO thin film may be doped with Al or B to have a low resistance of approximately 10-4 Ωcm or less. When the ZnO thin film is doped with B, light transmissivity increases in a near infrared region to increase a short circuit current.
  • The ZnO thin film may be deposited using a radio frequency (RF) sputtering method with a ZnO target, or using a reactive sputtering method with a Zn target, or using a metal organic chemical vapor deposition method.
  • A double structure that an indium tin oxide (ITO) thin film having excellent electro-optical characteristics is deposited on a ZnO thin film may be used.
  • A solar cell according to an embodiment of the present invention will now be compared with a solar cell in the related art.
  • A light absorption layer of the solar cell in the related art includes only a CuInGaSe2 thin film that is a P type semiconductor forms a PN junction with a ZnO thin film that is an N-type semiconductor and is used as a window layer.
  • However, since the CuInGaSe2 thin film is quite different from the ZnO thin film in lattice constant and energy band, a buffer layer is necessary therebetween for a junction without a defect.
  • The buffer layer is formed of CdS. However, Cd is poisonous, and a wet chemical process is used for the buffer layer, unlike other thin films.
  • Thus, toxic materials are used for removing surface and interface contamination due to a hetero junction, and the solar cell may be degraded.
  • In the light absorption layer 3 of the solar cell according to the embodiment of the present invention, since the P type CIGS layer 31 is coupled to the N-type CIGS layer 32 to form a single junction, the quality of the thin film is improved, and thus, the performance of the solar cell is improved. In addition, since CdS constituting a buffer layer is not used, environmental pollutions can be prevented.
  • As described above, according to the embodiment of the present invention, the P type CIGS layer 31 is coupled to the N-type CIGS layer 32 to form the solar cell including the light absorption layer 3 in a single junction structure, and thus, surface and interface contamination due to a buffer layer and environmental pollutions due to a toxic element can be prevented, and the performance of the solar cell can be improved.
  • While the present invention has been described with respect to the specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims (3)

What is claimed is:
1. A single junction type GIGS (Cu (In, Ga) Se2) thin film solar cell comprising:
a substrate;
a back contact disposed on the substrate;
a light absorption layer disposed on the back contact and comprising a single junction diode comprising a GIGS thin film; and
a reflection prevention film disposed on the light absorption layer.
2. The single junction type GIGS thin film solar cell of claim 1, wherein the light absorption layer comprises:
a P type GIGS layer disposed on the back contact; and
an N type GIGS layer disposed on the P type GIGS layer using a single junction.
3. The single junction type GIGS thin film solar cell of claim 1, further comprising a window layer disposed on the N type GIGS layer between the light absorption layer and the reflection prevention film.
US14/135,621 2010-11-03 2013-12-20 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell Abandoned US20140109963A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/135,621 US20140109963A1 (en) 2010-11-03 2013-12-20 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR10-2010-0108880 2010-11-03
KR1020100108880A KR101426821B1 (en) 2010-11-03 2010-11-03 THIN FILM SOLAR CELL USING SINGLE JUNCTION Cu(In,Ga)Se2 AND METHOD FOR MANUFACTURING THEREOF
US13/207,825 US8637765B2 (en) 2010-11-03 2011-08-11 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell
US14/135,621 US20140109963A1 (en) 2010-11-03 2013-12-20 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US13/207,825 Division US8637765B2 (en) 2010-11-03 2011-08-11 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Publications (1)

Publication Number Publication Date
US20140109963A1 true US20140109963A1 (en) 2014-04-24

Family

ID=45995311

Family Applications (2)

Application Number Title Priority Date Filing Date
US13/207,825 Expired - Fee Related US8637765B2 (en) 2010-11-03 2011-08-11 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell
US14/135,621 Abandoned US20140109963A1 (en) 2010-11-03 2013-12-20 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US13/207,825 Expired - Fee Related US8637765B2 (en) 2010-11-03 2011-08-11 Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Country Status (2)

Country Link
US (2) US8637765B2 (en)
KR (1) KR101426821B1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9634166B2 (en) 2015-06-26 2017-04-25 International Business Machines Corporation Thin film photovoltaic cell with back contacts
US10650262B2 (en) 2016-11-09 2020-05-12 Clicpic, Inc. Electronic system for comparing positions of interest on media items

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6377338B2 (en) * 2012-11-20 2018-08-22 株式会社東芝 Photoelectric conversion element, method for manufacturing photoelectric conversion element, and solar cell
KR101459039B1 (en) * 2013-03-04 2014-11-10 엘에스엠트론 주식회사 Thin film solar cell and Method of fabricating the same
JP6071690B2 (en) * 2013-03-26 2017-02-01 株式会社東芝 Solar cell
JP2015061062A (en) * 2013-09-20 2015-03-30 株式会社東芝 Photoelectric conversion element manufacturing method
JP2017017218A (en) * 2015-07-02 2017-01-19 三菱マテリアル株式会社 Method of manufacturing photoelectric conversion element and photoelectric conversion element

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1074968A (en) * 1996-09-02 1998-03-17 Nippon Telegr & Teleph Corp <Ntt> Solar cell and its manufacture
US20080190483A1 (en) * 2007-02-13 2008-08-14 Carpenter R Douglas Composition and method of preparing nanoscale thin film photovoltaic materials
US20100229951A1 (en) * 2009-03-13 2010-09-16 Tdk Corporation Solar cell, and method for producing the solar cell

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3558527A (en) * 1964-04-03 1971-01-26 Hitachi Ltd Method of producing cathodoconductive target from selenium and an alkali metal
JP2005303201A (en) 2004-04-15 2005-10-27 Matsushita Electric Ind Co Ltd Compound semiconductor, solar cell, and method for manufacturing them
US7235736B1 (en) * 2006-03-18 2007-06-26 Solyndra, Inc. Monolithic integration of cylindrical solar cells
US20090293955A1 (en) * 2007-11-07 2009-12-03 Qualcomm Incorporated Photovoltaics with interferometric masks
JP2011508430A (en) * 2007-12-21 2011-03-10 クォルコム・メムズ・テクノロジーズ・インコーポレーテッド Multi-junction photovoltaic cell
KR20100006205A (en) * 2008-07-09 2010-01-19 (주)텔리오솔라코리아 Cigs solarcells module and manufacturing method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1074968A (en) * 1996-09-02 1998-03-17 Nippon Telegr & Teleph Corp <Ntt> Solar cell and its manufacture
US20080190483A1 (en) * 2007-02-13 2008-08-14 Carpenter R Douglas Composition and method of preparing nanoscale thin film photovoltaic materials
US20100229951A1 (en) * 2009-03-13 2010-09-16 Tdk Corporation Solar cell, and method for producing the solar cell

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Machine translation of JP10-074968A. *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9634166B2 (en) 2015-06-26 2017-04-25 International Business Machines Corporation Thin film photovoltaic cell with back contacts
US9859451B2 (en) 2015-06-26 2018-01-02 International Business Machines Corporation Thin film photovoltaic cell with back contacts
US10651327B2 (en) 2015-06-26 2020-05-12 International Business Machines Corporation Thin film photovoltaic cell with back contacts
US10741710B2 (en) 2015-06-26 2020-08-11 International Business Machines Corporation Thin film photovoltaic cell with back contacts
US10650262B2 (en) 2016-11-09 2020-05-12 Clicpic, Inc. Electronic system for comparing positions of interest on media items
US11055556B2 (en) 2016-11-09 2021-07-06 Clicpic, Inc. Electronic system for comparing positions of interest on media items

Also Published As

Publication number Publication date
KR101426821B1 (en) 2014-08-06
KR20120047162A (en) 2012-05-11
US20120103418A1 (en) 2012-05-03
US8637765B2 (en) 2014-01-28

Similar Documents

Publication Publication Date Title
Efaz et al. A review of primary technologies of thin-film solar cells
US20140109963A1 (en) Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell
US20110024793A1 (en) Bulk heterojunction solar cell and method of manufacturing the same
US20120199191A1 (en) Battery and solar method for manufacturing the same
KR101081294B1 (en) Solar cell and method of fabricating the same
US20160284882A1 (en) Solar Cell
US20140238479A1 (en) Thin film solar cell
US20120266950A1 (en) Solar battery and method for manufacturing the same
US8852991B2 (en) Methods of manufacturing solar cell
JP2004296749A (en) Double-sided solar cell
KR101983422B1 (en) Cigs-compound solar cell
US20140007934A1 (en) Thin film solar cell and method of fabricating the same
KR101081270B1 (en) Solar cell and method of fabircating the same
KR101415251B1 (en) Multiple-Layered Buffer, and Its Fabrication Method, and Solor Cell with Multiple-Layered Buffer.
JP2014503125A (en) Solar cell and manufacturing method thereof
US20120125425A1 (en) Compound semiconductor solar cell and method of manufacturing the same
KR101154696B1 (en) Solar cell apparatus and method of fabricating the same
US8258003B2 (en) Manufacturing method of compound semiconductor solar cell
KR20110012954A (en) Method of manufacturing thin film solar cell
US9331218B2 (en) Solar cell module and method of manufacturing the same
JP5977166B2 (en) Photoelectric conversion element
KR20130031020A (en) Solar cell
KR101485009B1 (en) fabricating method of CIGS base thin film solar cell and solar cell thereof
KR101849267B1 (en) A thin film solar cell and the method of fabricating the same
US20120125426A1 (en) Compound semiconductor solar cell

Legal Events

Date Code Title Description
AS Assignment

Owner name: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTIT

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHUNG, YONG-DUCK;HAN, WON SEOK;REEL/FRAME:031825/0516

Effective date: 20131210

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION