Journal Article

The Effect of ALD-Zn(O,S) Buffer Layer on the Performance of CIGSSe Thin Film Solar Cells

Kim, Yangdo, Hwang, Donghyun, Park, Wan Woo, Son, Chang Sik, Choi, Woo-Jin

2020

Overview

In this paper, we report the development of Cd-free buffers using atomic layer deposition (ALD) for Cu(In,Ga)(S,Se)2-based solar cells. The ALD process gives good control of thickness and the S/S +O ratio content of the films. The influence of the growth per cycle (GPC) and the S/(S+O) ratio, and the glass temperature of the atomic layer deposited Zn(O,S) buffer layers on the efficiency of the Cu(In,Ga)(S,Se)2 solar cells were investigated. We present the first results from our work on cadmium-free CIGS solar cells on substrates with an aperture area of 0.4 cm2. These Zn(O,S) layers were deposited by atomic layer deposition at 120 °C with S/Zn ratios of 0.7, and layers of around 30 nm. The Zn(O,S) 20% (Pulse Ratio: H2S/H2O+H2S) process results in a S/Zn ratio of 0.7. We achieved independently certified aperture area efficiencies of 17.1% for 0.4 cm2 cells.

• Publisher: MDPI AG
• Subject: Alternative energy sources / atomic layer deposition / buffer layer / cu(in,ga)(s,se)2 absorber layer / Efficiency / Gases / Optical properties / Organic chemicals / Photovoltaic cells / Renewable resources / solar cell / Sulfur content / Thin films / zn(o,s) ratio / zn(o,s) temperature window / zn(o,s) thickness