Rubidium Fluoride Post-Deposition Treatment: Impact on the Chemical Structure of the Cu(In,Ga)Se2 Surface and CdS/Cu(In,Ga)Se2 Interface in Thin-Film Solar Cells

Kreikemeyer-Lorenzo, Dagmar; Hauschild, Dirk; Jackson, Philip; Friedlmeier, Theresa M.; Hariskos, Dimitrios; Blum, Monika; Yang, Wanli; Reinert, Friedrich; Powalla, Michael; Heske, Clemens; Weinhardt, Lothar

doi:10.1021/acsami.8b10005

Rubidium Fluoride Post-Deposition Treatment: Impact on the Chemical Structure of the Cu(In,Ga)Se₂ Surface and CdS/Cu(In,Ga)Se₂ Interface in Thin-Film Solar Cells

Journal Article · Mon Oct 01 00:00:00 EDT 2018 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.8b10005· OSTI ID:1594899

Kreikemeyer-Lorenzo, Dagmar ^[1]; ^[2]; Jackson, Philip ^[3]; Friedlmeier, Theresa M. ^[3]; Hariskos, Dimitrios ^[3]; Blum, Monika ^[4]; ^[5]; Reinert, Friedrich ^[6]; Powalla, Michael ^[3]; Heske, Clemens ^[7]; Weinhardt, Lothar ^[7]

Karlsruhe Inst. of Technology (KIT), Hermann-v.-Helmholtz-Platz (Germany)
Karlsruhe Inst. of Technology (KIT), Hermann-v.-Helmholtz-Platz (Germany); Univ. of Würzburg (Germany)
Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Stuttgart (Germany)
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Univ. of Nevada, Las Vegas, NV (United States)
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
Univ. of Würzburg (Germany)
Karlsruhe Inst. of Technology (KIT), Hermann-v.-Helmholtz-Platz (Germany); Univ. of Nevada, Las Vegas, NV (United States)

Here, we present a detailed characterization of the chemical structure of the Cu(In,Ga)Se₂ thin-film surface and the CdS/Cu(In,Ga)Se₂ interface, both with and without a RbF post-deposition treatment (RbF-PDT). For this purpose, X-ray photoelectron and Auger electron spectroscopy, as well as synchrotron-based soft X-ray emission spectroscopy have been employed. Although some similarities with the reported impacts of light-element alkali PDT (i.e., NaF- and KF-PDT) are found, we observe some distinct differences, which might be the reason for the further improved conversion efficiency with heavy-element alkali PDT. In particular, we find that the RbF-PDT reduces, but not fully removes, the copper content at the absorber surface and does not induce a significant change in the Ga/(Ga + In) ratio. Additionally, we observe an increased amount of indium and gallium oxides at the surface of the treated absorber. These oxides are partly (in the case of indium) and completely (in the case of gallium) removed from the CdS/Cu(In,Ga)Se₂ interface by the chemical bath deposition of the CdS buffer.

View Accepted Manuscript (DOE)

Research Organization:: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

Grant/Contract Number:: AC02-05CH11231

OSTI ID:: 1594899

Journal Information:: ACS Applied Materials and Interfaces, Journal Name: ACS Applied Materials and Interfaces Journal Issue: 43 Vol. 10; ISSN 1944-8244

Publisher:: American Chemical Society (ACS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited By (3)

Surface and Interface Properties in Thin‐Film Solar Cells: Using Soft X‐rays and Electrons to Unravel the Electronic and Chemical Structure Weinhardt, Lothar; Hauschild, Dirk; Heske, Clemens Advanced Materials, Vol. 31, Issue 26 https://doi.org/10.1002/adma.201806660	journal	February 2019
Heavy Alkali Treatment of Cu(In,Ga)Se ₂ Solar Cells: Surface versus Bulk Effects Siebentritt, Susanne; Avancini, Enrico; Bär, Marcus Advanced Energy Materials, Vol. 10, Issue 8 https://doi.org/10.1002/aenm.201903752	journal	January 2020
Surface and Interface Properties in Thin-Film Solar Cells: Using Soft X-rays and Electrons to Unravel the Electronic and Chemical Structure Weinhardt, Lothar; Hauschild, Dirk; Heske, Clemens Karlsruhe https://doi.org/10.5445/ir/1000093239	text	January 2019

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Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CIGSe solar cell
Cu(In
Ga)Se2
RbF post-deposition treatment
chemical structure
high efficiency
soft X-ray spectroscopy
thin films