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
Document Type
Article
Publication Date
1-1-2016
Publication Title
ACS Applied Materials and Interfaces
Volume
8
Issue
48
First page number:
33256
Last page number:
33263
Abstract
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. © 2016 American Chemical Society.
Keywords
alternative buffer layers; chalcopyrite thin-film solar cell; chemical structure; X-ray emission spectroscopy; X-ray photoelectron spectroscopy; Zn(O; S)
Language
English
Repository Citation
Mezher, M.,
Garris, R.,
Mansfield, L. M.,
Blum, M.,
Hauschild, D.,
Horsley, K.,
Duncan, D. A.,
Yang, W.,
Bär, M.,
Weinhardt, L.,
Ramanathan, K.,
Heske, C.
(2016).
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.
ACS Applied Materials and Interfaces, 8(48),
33256-33263.
http://dx.doi.org/10.1021/acsami.6b09245