KR20170076814A - 후면 전극형 태양 전지를 제조하는 방법 및 그 장치 - Google Patents

후면 전극형 태양 전지를 제조하는 방법 및 그 장치 Download PDF

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Publication number
KR20170076814A
KR20170076814A KR1020177017550A KR20177017550A KR20170076814A KR 20170076814 A KR20170076814 A KR 20170076814A KR 1020177017550 A KR1020177017550 A KR 1020177017550A KR 20177017550 A KR20177017550 A KR 20177017550A KR 20170076814 A KR20170076814 A KR 20170076814A
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KR
South Korea
Prior art keywords
solar cell
material layer
back electrode
substrate
dopant source
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Ceased
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KR1020177017550A
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English (en)
Korean (ko)
Inventor
보 리
데이비드 스미스
피터 코신스
Original Assignee
선파워 코포레이션
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Application filed by 선파워 코포레이션 filed Critical 선파워 코포레이션
Publication of KR20170076814A publication Critical patent/KR20170076814A/ko
Ceased legal-status Critical Current

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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F77/00—Constructional details of devices covered by this subclass
    • H10F77/20—Electrodes
    • H10F77/206—Electrodes for devices having potential barriers
    • H10F77/211—Electrodes for devices having potential barriers for photovoltaic cells
    • H10F77/219—Arrangements for electrodes of back-contact photovoltaic cells
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F77/00—Constructional details of devices covered by this subclass
    • H10F77/70—Surface textures, e.g. pyramid structures
    • H10F77/703—Surface textures, e.g. pyramid structures of the semiconductor bodies, e.g. textured active layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F19/00—Integrated devices, or assemblies of multiple devices, comprising at least one photovoltaic cell covered by group H10F10/00, e.g. photovoltaic modules
    • H01L31/022441—
    • H01L31/02366—
    • H01L31/0682—
    • H01L31/18—
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F10/00—Individual photovoltaic cells, e.g. solar cells
    • H10F10/10—Individual photovoltaic cells, e.g. solar cells having potential barriers
    • H10F10/14—Photovoltaic cells having only PN homojunction potential barriers
    • H10F10/146—Back-junction photovoltaic cells, e.g. having interdigitated base-emitter regions on the back side
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F71/00—Manufacture or treatment of devices covered by this subclass
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F71/00—Manufacture or treatment of devices covered by this subclass
    • H10F71/121—The active layers comprising only Group IV materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F71/00—Manufacture or treatment of devices covered by this subclass
    • H10F71/121—The active layers comprising only Group IV materials
    • H10F71/1221—The active layers comprising only Group IV materials comprising polycrystalline silicon
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F77/00—Constructional details of devices covered by this subclass
    • H10F77/70—Surface textures, e.g. pyramid structures
    • H10F77/707—Surface textures, e.g. pyramid structures of the substrates or of layers on substrates, e.g. textured ITO layer on a glass substrate
    • 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
    • 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
    • Y02E10/546—Polycrystalline 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
    • 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

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  • Photovoltaic Devices (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
KR1020177017550A 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치 Ceased KR20170076814A (ko)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US31065510P 2010-03-04 2010-03-04
US61/310,655 2010-03-04
US12/972,247 US8790957B2 (en) 2010-03-04 2010-12-17 Method of fabricating a back-contact solar cell and device thereof
US12/972,247 2010-12-17
PCT/US2010/062264 WO2011109058A2 (en) 2010-03-04 2010-12-28 Method of fabricating a back-contact solar cell and device thereof

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
KR1020127025955A Division KR20130004917A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치

Related Child Applications (1)

Application Number Title Priority Date Filing Date
KR1020187016046A Division KR20180066275A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치

Publications (1)

Publication Number Publication Date
KR20170076814A true KR20170076814A (ko) 2017-07-04

Family

ID=44530256

Family Applications (3)

Application Number Title Priority Date Filing Date
KR1020177017550A Ceased KR20170076814A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치
KR1020127025955A Ceased KR20130004917A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치
KR1020187016046A Ceased KR20180066275A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치

Family Applications After (2)

Application Number Title Priority Date Filing Date
KR1020127025955A Ceased KR20130004917A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치
KR1020187016046A Ceased KR20180066275A (ko) 2010-03-04 2010-12-28 후면 전극형 태양 전지를 제조하는 방법 및 그 장치

Country Status (7)

Country Link
US (2) US8790957B2 (https=)
JP (2) JP5637640B2 (https=)
KR (3) KR20170076814A (https=)
CN (2) CN102870225B (https=)
AU (1) AU2010347232B2 (https=)
DE (1) DE112010005344B4 (https=)
WO (1) WO2011109058A2 (https=)

Families Citing this family (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0652434A (ja) * 1992-07-28 1994-02-25 Murata Mfg Co Ltd カップベンダー吐出ノズル
JP3174907B2 (ja) 1996-12-16 2001-06-11 株式会社ジーデイーエス 電荷信号均一化装置
US8790957B2 (en) * 2010-03-04 2014-07-29 Sunpower Corporation Method of fabricating a back-contact solar cell and device thereof
US10011920B2 (en) 2011-02-23 2018-07-03 International Business Machines Corporation Low-temperature selective epitaxial growth of silicon for device integration
US8586397B2 (en) * 2011-09-30 2013-11-19 Sunpower Corporation Method for forming diffusion regions in a silicon substrate
US9202965B2 (en) * 2011-12-16 2015-12-01 Jusung Engineering Co., Ltd. Method for manufacturing solar cell
US20130247967A1 (en) * 2012-03-23 2013-09-26 Scott Harrington Gaseous ozone (o3) treatment for solar cell fabrication
US9059212B2 (en) 2012-10-31 2015-06-16 International Business Machines Corporation Back-end transistors with highly doped low-temperature contacts
US20140130854A1 (en) * 2012-11-12 2014-05-15 Samsung Sdi Co., Ltd. Photoelectric device and the manufacturing method thereof
US8912071B2 (en) 2012-12-06 2014-12-16 International Business Machines Corporation Selective emitter photovoltaic device
US8642378B1 (en) * 2012-12-18 2014-02-04 International Business Machines Corporation Field-effect inter-digitated back contact photovoltaic device
US9236509B2 (en) * 2013-04-24 2016-01-12 Natcore Technology, Inc. Solar cells with patterned antireflective surfaces
TW201442261A (zh) * 2013-04-30 2014-11-01 Terasolar Energy Materials Corp 矽晶太陽能電池的製造方法以及矽晶太陽能電池
JP6114170B2 (ja) * 2013-12-05 2017-04-12 信越化学工業株式会社 太陽電池の製造方法
US9401450B2 (en) * 2013-12-09 2016-07-26 Sunpower Corporation Solar cell emitter region fabrication using ion implantation
US9837259B2 (en) 2014-08-29 2017-12-05 Sunpower Corporation Sequential etching treatment for solar cell fabrication
US9246046B1 (en) * 2014-09-26 2016-01-26 Sunpower Corporation Etching processes for solar cell fabrication
US11355657B2 (en) * 2015-03-27 2022-06-07 Sunpower Corporation Metallization of solar cells with differentiated p-type and n-type region architectures
NL2015534B1 (en) * 2015-09-30 2017-05-10 Tempress Ip B V Method of manufacturing a solar cell.
US9607847B1 (en) * 2015-12-18 2017-03-28 Texas Instruments Incorporated Enhanced lateral cavity etch
US10217878B2 (en) 2016-04-01 2019-02-26 Sunpower Corporation Tri-layer semiconductor stacks for patterning features on solar cells
USD822890S1 (en) 2016-09-07 2018-07-10 Felxtronics Ap, Llc Lighting apparatus
FR3058264B1 (fr) * 2016-10-28 2020-10-02 Commissariat Energie Atomique Procede de fabrication de cellules photovoltaiques a contacts arriere.
WO2018092189A1 (ja) 2016-11-15 2018-05-24 信越化学工業株式会社 高光電変換効率太陽電池、その製造方法、太陽電池モジュール及び太陽光発電システム
US10775030B2 (en) 2017-05-05 2020-09-15 Flex Ltd. Light fixture device including rotatable light modules
USD832494S1 (en) 2017-08-09 2018-10-30 Flex Ltd. Lighting module heatsink
USD877964S1 (en) 2017-08-09 2020-03-10 Flex Ltd. Lighting module
USD833061S1 (en) 2017-08-09 2018-11-06 Flex Ltd. Lighting module locking endcap
USD862777S1 (en) 2017-08-09 2019-10-08 Flex Ltd. Lighting module wide distribution lens
USD846793S1 (en) 2017-08-09 2019-04-23 Flex Ltd. Lighting module locking mechanism
USD872319S1 (en) 2017-08-09 2020-01-07 Flex Ltd. Lighting module LED light board
USD832495S1 (en) 2017-08-18 2018-10-30 Flex Ltd. Lighting module locking mechanism
USD862778S1 (en) 2017-08-22 2019-10-08 Flex Ltd Lighting module lens
USD888323S1 (en) 2017-09-07 2020-06-23 Flex Ltd Lighting module wire guard
FR3112427A1 (fr) * 2020-07-13 2022-01-14 Semco Smartech France Formation de contacts passivés pour cellules solaires IBC
EP3982421A1 (en) 2020-10-09 2022-04-13 International Solar Energy Research Center Konstanz E.V. Method for local modification of etching resistance in a silicon layer, use of this method in the production of passivating contact solar cells and thus-created solar cell
CN118738214A (zh) * 2021-09-30 2024-10-01 泰州隆基乐叶光伏科技有限公司 一种背接触电池及其制作方法
EP4195299A1 (en) 2021-12-13 2023-06-14 International Solar Energy Research Center Konstanz E.V. Interdigitated back contact solar cell and method for producing an interdigitated back contact solar cell
CN117727810A (zh) * 2023-12-14 2024-03-19 浙江晶科能源有限公司 太阳能电池及其制造方法、光伏组件
CN118073471A (zh) * 2024-02-18 2024-05-24 天合光能股份有限公司 背接触太阳能电池及其制备方法

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5057439A (en) * 1990-02-12 1991-10-15 Electric Power Research Institute Method of fabricating polysilicon emitters for solar cells
JPH11177046A (ja) 1997-12-09 1999-07-02 Toshiba Corp 半導体装置及びその製造方法並びにキャパシタの製造方法
US5888309A (en) 1997-12-29 1999-03-30 Taiwan Semiconductor Manufacturing Company, Ltd. Lateral etch inhibited multiple for forming a via through a microelectronics layer susceptible to etching within a fluorine containing plasma followed by an oxygen containing plasma
US6287961B1 (en) 1999-01-04 2001-09-11 Taiwan Semiconductor Manufacturing Company Dual damascene patterned conductor layer formation method without etch stop layer
JP2005064014A (ja) * 2003-08-11 2005-03-10 Sharp Corp 薄膜結晶太陽電池およびその製造方法
DE102004050269A1 (de) 2004-10-14 2006-04-20 Institut Für Solarenergieforschung Gmbh Verfahren zur Kontakttrennung elektrisch leitfähiger Schichten auf rückkontaktierten Solarzellen und Solarzelle
US7799371B2 (en) * 2005-11-17 2010-09-21 Palo Alto Research Center Incorporated Extruding/dispensing multiple materials to form high-aspect ratio extruded structures
AU2006335142B2 (en) * 2005-12-21 2011-09-22 Sunpower Corporation Back side contact solar cell structures and fabrication processes
KR101212198B1 (ko) * 2006-04-06 2012-12-13 삼성에스디아이 주식회사 태양 전지
US7737357B2 (en) * 2006-05-04 2010-06-15 Sunpower Corporation Solar cell having doped semiconductor heterojunction contacts
US20080000522A1 (en) * 2006-06-30 2008-01-03 General Electric Company Photovoltaic device which includes all-back-contact configuration; and related processes
US7928015B2 (en) * 2006-12-12 2011-04-19 Palo Alto Research Center Incorporated Solar cell fabrication using extruded dopant-bearing materials
CN101743640B (zh) * 2007-07-26 2012-12-19 康斯坦茨大学 具有回蚀刻发射极的硅太阳能电池的制造方法和相应的太阳能电池
JP5236914B2 (ja) * 2007-09-19 2013-07-17 シャープ株式会社 太陽電池の製造方法
US8349644B2 (en) * 2007-10-18 2013-01-08 e-Cube Energy Technologies, Ltd. Mono-silicon solar cells
US7851698B2 (en) 2008-06-12 2010-12-14 Sunpower Corporation Trench process and structure for backside contact solar cells with polysilicon doped regions
KR101472018B1 (ko) * 2008-10-13 2014-12-15 엘지전자 주식회사 후면전극 태양전지 및 그 제조방법
US8790957B2 (en) 2010-03-04 2014-07-29 Sunpower Corporation Method of fabricating a back-contact solar cell and device thereof

Also Published As

Publication number Publication date
CN106057934A (zh) 2016-10-26
CN102870225A (zh) 2013-01-09
US20140305501A1 (en) 2014-10-16
DE112010005344T5 (de) 2012-12-13
DE112010005344B4 (de) 2024-03-21
JP5637640B2 (ja) 2014-12-10
AU2010347232A1 (en) 2012-09-27
WO2011109058A3 (en) 2011-11-17
US9406821B2 (en) 2016-08-02
US20110214719A1 (en) 2011-09-08
US8790957B2 (en) 2014-07-29
KR20180066275A (ko) 2018-06-18
CN106057934B (zh) 2018-08-10
CN102870225B (zh) 2016-07-06
JP2015062232A (ja) 2015-04-02
KR20130004917A (ko) 2013-01-14
AU2010347232B2 (en) 2014-08-07
WO2011109058A2 (en) 2011-09-09
JP2013521645A (ja) 2013-06-10

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