Interface engineering of Cu(In,Ga)Se₂and atomic layer deposited Zn(O,S) heterojunctions

Abstract

Atomic layer deposition of Zn(O,S) is an attractive dry and Cd-free process for the preparation of buffer layers for chalcopyrite solar modules. As we previously reported, excellent cell and module efficiencies were achieved using absorbers from industrial pilot production. These absorbers were grown using a selenization/sulfurization process. In this contribution we report on the interface engineering required to adapt the process to sulfur-free multi source evaporated absorbers. Different approaches to a local sulfur enrichment at the heterojunction have been studied by using surface analysis (XPS) and scanning transmission electron microscopy. We correlate the microstructure and element distribution at the interface with device properties obtained by electronic characterization. The optimized completely dry process yields cell efficiencies >16% and 30 × 30 cm2 minimodule efficiencies of up to 13.9% on industrial substrates. Any degradation observed in the dry heat stress test is fully reversible after light soaking.

CIGS photovoltaics: reviewing an evolving paradigm

“…For instance, Solar Frontier deposited a Zn(O,S,OH) x buffer layer and applied it to CIGS modules [200], and Hubert et al studied the CBD Zn(O,S,OH) x growth mechanism [201]. Recent buffer layer developments include ALD Zn(O,S) [202], ALD ZnO [203], sputtered In x S y [204], and ZnS/(Zn,Mg)O [205]. Many groups have investigated the quality of the CIGS/buffer interface using transmission electron microscopy [182,206,207], and the passivation effect of buffer layers has become widely accepted in the CIGS community.…”

Numerical simulation of contact surface stress distribution based on stress-magnetization effect surface

“…In recent years, magnetic non-destructive testing technology based on the magnetization theory of ferromagnetic materials has developed rapidly [10]. This technology can not only quickly detect the stress state of materials, but also evaluate the damage state of materials [11][12][13]. Roskosz et al applied the magnetic memory method to evaluate the stress distribution of specimens containing holes under tension [14].…”