Effects of annealing atmosphere on the performance of Cu(InGa)Se2 films sputtered from quaternary targets. Issue 10 (7th October 2020)

• Record Type: Journal Article
• Authors: Zhang, Leng; Yu, Yongyi; Yu, Jing; Wei, Yaowei
• Is Part Of: Royal Society open science. Volume 7:Issue 10(2020)
• Publication Date: 2020-10-07
• Subjects: Cu(InGa)Se2 -- quaternary target -- Se-free annealing -- Se-containing annealing; Science -- Periodicals; 500
• DOI: 10.1098/rsos.200662
• Languages: English
• ISSNs: 2054-5703

Abstract

Abstract : Quaternary sputtering without additional selenization is a low-cost alternative method for the preparation of Cu(InGa)Se2 (CIGS) thin film for photovoltaics. However, without selenization, the device efficiency is much lower than that with selenization. To comprehensively examine this problem, we compared the morphologies, depth profiles, compositions, electrical properties and recombination mechanism of the absorbers fabricated with and without additional selenization. The results revealed that the amount of surface Se on CIGS films annealed in a Se-free atmosphere is less than that on CIGS films annealed in a Se-containing atmosphere. Additionally, the lower amount of surface Se reduced the carrier concentration, enhanced the resistivity of the CIGS film and allowed CIGS/CdS interface recombination to be the dominant recombination mechanism of CIGS device. The increase of interface recombination reduced the efficiency of the device annealed in a Se-free atmosphere.