Development of n-type buffer layer and window layer for low band gap CIS solar cells

Description

This study focuses on replacing the highly toxic and low bandgap CdS buffer layer
used in CIGS solar cells with a more efficient alternative. The Zn(O,S) buffer layer was
used and optimized through 10 experiments to determine the best recipe for producing
high-performance solar cells and to control the conduction band offset by varying the
concentrations of Zinc and Sulphur while depositing Zn(O,S) through a chemical bath
deposition (CBD) process and also to find the perfect band alignment for the low
bandgap CIS solar cells. The solar cell structure fabricated is shown in figure1. The quality and the uniformity of the CBD deposited Zn(O,S) layers were studied using SEM, EDX, PL spectroscopy and Lifetime measurements. JMP software was used to design the experiments and then analyse the dependency of CBD process on solar cells. The JV results showed that the solar cells with Zn(O,S) buffer layer improved after light soaking for 20 minutes and air annealing at 200 °C for 5 minutes shown in figure2. The optimal recipe for chemical bath deposition of Zn(O,S) was determined, producing results comparable to solar cells with CdS as the buffer layer.

Period	5 Jul 2023 → 7 Jul 2023
Event title	13th Kesterite workshop
Event type	Conference
Location	Barcelona, SpainShow on map
Degree of Recognition	International