Soft x-ray spectroscopy of a complex heterojunction in high-efficiency thin-film photovoltaics: Intermixing and Zn speciation at the Zn(O,S)/Cu(In,Ga)Se2 interface

Mezher, Michelle; Garris, Rebekah; Mansfield, Lorelle M.; Blum, Monika; Hauschild, Dirk; Horsley, Kimberly; Duncan, Douglas A.; Yang, Wanli; Bär, Marcus; Weinhardt, Lothar; Ramanathan, Kannan; Heske, Clemens

doi:10.1021/acsami.6b09245

Soft x-ray spectroscopy of a complex heterojunction in high-efficiency thin-film photovoltaics: Intermixing and Zn speciation at the Zn(O,S)/Cu(In,Ga)Se₂ interface

Journal Article · Fri Nov 11 00:00:00 EST 2016 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.6b09245· OSTI ID:1337540

Mezher, Michelle ^[1]; Garris, Rebekah ^[2]; Mansfield, Lorelle M. ^[2]; Blum, Monika ^[1]; Hauschild, Dirk ^[3]; Horsley, Kimberly ^[1]; Duncan, Douglas A. ^[1]; Yang, Wanli ^[4]; Bär, Marcus ^[5]; Weinhardt, Lothar ^[6]; Ramanathan, Kannan ^[2]; Heske, Clemens ^[6]

Univ. of Nevada, Las Vegas (UNLV), Las Vegas, NV (United States)
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany); Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Univ. of Nevada, Las Vegas (UNLV), Las Vegas, NV (United States); Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH, Berlin (Germany); Brandenburgische Technische Univ. Cottbus-Senftenberg, Cottbus (Germany)
Univ. of Nevada, Las Vegas (UNLV), Las Vegas, NV (United States); Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany); Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)

In this study, the chemical structure of the Zn(O,S)/Cu(In,Ga)Se₂ interface in high-efficiency photovoltaic devices is investigated using X-ray photoelectron and Auger electron spectroscopy, as well as soft X-ray emission spectroscopy. We find that the Ga/(Ga+In) ratio at the absorber surface does not change with the formation of the Zn(O,S)/Cu(In,Ga)Se₂ interface. Furthermore, we find evidence for Zn in multiple bonding environments, including ZnS, ZnO, Zn(OH)₂, and ZnSe. We also observe dehydrogenation of the Zn(O,S) buffer layer after Ar+ ion treatment. Similar to high-efficiency CdS/Cu(In,Ga)Se₂ devices, intermixing occurs at the interface, with diffusion of Se into the buffer, and the formation of S—In and/or S—Ga bonds at or close to the interface.

View Accepted Manuscript (DOE)

Research Organization:: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); NREL (National Renewable Energy Laboratory (NREL), Golden, CO (United States))

Sponsoring Organization:: SunShot Foundational Program to Advance Cell Efficiency (F-PACE); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

Grant/Contract Number:: AC02-05CH11231; AC36-08GO28308

OSTI ID:: 1337540

Alternate ID(s):: OSTI ID: 1474987

Report Number(s):: NREL/JA--5K00-67637

Journal Information:: ACS Applied Materials and Interfaces, Journal Name: ACS Applied Materials and Interfaces Journal Issue: 48 Vol. 8; ISSN 1944-8244

Publisher:: American Chemical Society (ACS)Copyright Statement

Country of Publication:: United States

Language:: English

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Improving performance by Na doping of a buffer layer-chemical and electronic structure of the In _x S _y :Na/CuIn(S,Se) ₂ thin-film solar cell interface Hauschild, Dirk; Meyer, Frank; Benkert, Andreas Progress in Photovoltaics: Research and Applications, Vol. 26, Issue 5 https://doi.org/10.1002/pip.2993	journal	February 2018

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Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
X-ray emission spectroscopy
X-ray photoelectron spectroscopy
Zn(O
S)
alternative buffer layers
chalcopyrite thin-film solar cell
chemical structure