Chemical interaction of Na with cleaved (011) surfaces of CuInSe2
Year: 1996
Type: article
Abstract: To study the beneficial effect of sodium-containing substrate material on the photovoltaic properties of thin-film CuInSe2 solar cells the chemical interaction of Na with CuInSe2 has been investigated by synchrotron excited photoelectron spectroscopy. A clean CuInSe2 (011) surface was prepared by cleaving an oriented single crystal in UHV. The cleaved surface exhibits an electron affinity of χ≊4.6 eV. The Se 3d level shows a surface core level shift of −0.4 eV. Na was sequentially deposited in UHV in small steps from a commercial dispenser source. Initially ionized Na adsorbs on the surface leading to a shift of the surface Fermi level by 0.3 eV closer to the conduction band. Removal of Cu from the surface is observed. For higher Na deposition a chemical reaction of Na with the CuInSe2 surface occurs leading to the formation of metallic indium and Na2Se.
Source: Journal of Applied Physics
DOI: 10.1063/1.363549
Authors: A. Klein, T. Löher, C. Pettenkofer, W. Jaegermann
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2006286361