Microstructural Characterization of Sulfurization Effects in Cu(In,Ga)Se2 Thin Film Solar Cells
Journal article, 2019

Surface sulfurization of Cu(In,Ga)Se 2 (CIGSe) absorbers is a commonly applied technique to improve the conversion efficiency of the corresponding solar cells, via increasing the bandgap towards the heterojunction. However, the resulting device performance is understood to be highly dependent on the thermodynamic stability of the chalcogenide structure at the upper region of the absorber. The present investigation provides a high-resolution chemical analysis, using energy dispersive X-ray spectrometry and laser-pulsed atom probe tomography, to determine the sulfur incorporation and chemical re-distribution in the absorber material. The post-sulfurization treatment was performed by exposing the CIGSe surface to elemental sulfur vapor for 20 min at 500°C. Two distinct sulfur-rich phases were found at the surface of the absorber exhibiting a layered structure showing In-rich and Ga-rich zones, respectively. Furthermore, sulfur atoms were found to segregate at the absorber grain boundaries showing concentrations up to ∼7 at% with traces of diffusion outwards into the grain interior.

atom probe

solar cells

thin films

surface treatment

Cu(In,Ga)Se 2

Author

Hisham Aboulfadl

Chalmers, Physics, Microstructure Physics

Jan Keller

Uppsala University

Jes Larsen

Uppsala University

Mattias Thuvander

Chalmers, Physics, Microstructure Physics

Lars Riekehr

Uppsala University

Marika Edoff

Uppsala University

Charlotte Platzer-Björkman

Uppsala University

Microscopy and Microanalysis

1431-9276 (ISSN) 1435-8115 (eISSN)

Vol. 25 2 532-538

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Chemistry Topics

Driving Forces

Sustainable development

Areas of Advance

Energy

Materials Science

Infrastructure

Chalmers Materials Analysis Laboratory

DOI

10.1017/S1431927619000151

More information

Latest update

11/27/2020