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Title: 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 · · ACS Applied Materials and Interfaces
 [1];  [2];  [2];  [1];  [3];  [1];  [1];  [4];  [5];  [6];  [2];  [6]
  1. Univ. of Nevada, Las Vegas (UNLV), Las Vegas, NV (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany); Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)
  4. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  5. 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)
  6. 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)
+ Show Author Affiliations

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.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office; SunShot Foundational Program to Advance Cell Efficiency (F-PACE); USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
AC36-08GO28308; AC02-05CH11231
OSTI ID:
1337540
Alternate ID(s):
OSTI ID: 1474987
Report Number(s):
NREL/JA-5K00-67637
Journal Information:
ACS Applied Materials and Interfaces, Vol. 8, Issue 48; ISSN 1944-8244
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 4 works
Citation information provided by
Web of Science

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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 journal February 2018

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Related Subjects

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