Earth-abundant absorber based solar cells onto low weight stainless steel substrate

In this paper we demonstrate the potentiality to produce solar cells based in earth abundant materials deposited onto low weight and flexible stainless steel substrates. Due to the increasing interest of kesterite absorbers like those formed by Cu₂ZnSn(S,Se)₄, we deposited Cu ₂ZnSnSe₄ layers by a two stage method onto stainless steel substrates coated with a Chromium diffusion barrier, a Mo back contact and a ZnO intermediate layer as substrate configuration, obtaining photovoltaic grade absorbers. First preliminary results, using thermal treatments optimized for glass substrates, lead to a 3.5% efficiency solar cell. This is a promising result, showing the potentiality of this low cost technology for the development of devices onto flexible and low weight substrates, compatible with roll-to-roll industrial implementation.