The impact of Al2O3 back interface layer on low-temperature growth of ultrathin Cu(In,Ga)Se2 solar cells

• Published in: Optoelectronics letters Vol. 14; no. 5; pp. 363 - 366
• Main Authors: Liu, Yang, Liu, Wei, Chen, Meng-Xin, Shi, Si-Han, He, Zhi-Chao, Gong, Jin-Long, Wang, Tuo, Zhou, Zhi-Qiang, Liu, Fang-Fang, Sun, Yun, Xu, Shu
• Format: Journal Article
• Language: English
• Published: Tianjin Tianjin University of Technology 01.09.2018; Springer Nature B.V
• Subjects: Absorbers; Aluminum oxide; Atomic layer epitaxy; Copper indium gallium selenides; Lasers; Low temperature; Open circuit voltage; Optical Devices; Optics; Photonics; Photovoltaic cells; Physics; Physics and Astronomy; Silicon wafers; Solar cells; Thickness; A
• ISSN: 1673-1905; 1993-5013
• DOI: 10.1007/s11801-018-8036-7

With reducing the absorber layer thickness and processing temperature, the recombination at the back interface is severe, which both can result in the decrease of open-circuit voltage and fill factor. In this paper, we prepare Al 2 O 3 by atomic layer deposition (ALD), and investigate the effect of its thickness on the performance of Cu(In,Ga)Se 2 (CIGS) solar cell. The device recombination activation energy ( E A ) is increased from 1.04 eV to 1.11 eV when the thickness of Al 2 O 3 is varied from 0 nm to 1 nm, and the height of back barrier is decreased from 48.54 meV to 38.05 meV. An efficiency of 11.57 % is achieved with 0.88-μm-thick CIGS absorber layer.