A Highly Conductive Titanium Oxynitride Electron‐Selective Contact for Efficient Photovoltaic Devices

by Xinbo Yang, Yuanbao Lin, Jiang Liu, Wenzhu Liu, Qunyu Bi, Xin Song, Jingxuan Kang, Fuzong Xu, Lujia Xu, Mohamed N. Hedhili, Derya Baran, Xiaohong Zhang, Thomas D. Anthopoulos, Stefaan De Wolf

Communication Year: 2020 DOI: https://doi.org/10.1002/adma.202002608

Bibliography

Yang, X., Lin, Y., Liu, J., Liu, W., Bi, Q., Song, X., Kang, J., Xu, F., Xu, L., Hedhili, M. N., Baran, D., Zhang, X., Anthopoulos, T. D., De, S., A Highly Conductive Titanium Oxynitride Electron‐Selective Contact for Efficient Photovoltaic Devices. Advanced Materials 2020, 2002608.

Abstract

High‐quality carrier‐selective contacts with suitable electronic properties are a prerequisite for photovoltaic devices with high power conversion efficiency (PCE). In this work, an efficient electron‐selective contact, titanium oxynitride (TiOx Ny ), is developed for crystalline silicon (c‐Si) and organic photovoltaic devices. Atomic‐layer‐deposited TiOx Ny is demonstrated to be highly conductive with a proper work function (4.3 eV) and a wide bandgap (3.4 eV). Thin TiOx Ny films simultaneously provide a moderate surface passivation and enable a low contact resistivity on c‐Si surfaces. By implementation of an optimal TiOx Ny‐based contact, a state‐of‐the‐art PCE of 22.3% is achieved for a c‐Si solar cell featuring a full‐area dopant‐free electron‐selective contact. Simultaneously, conductive TiOx Ny is proven to be an efficient electron‐transport layer for organic photovoltaic (OPV) devices. A remarkably high PCE of 17.02% is achieved for an OPV device with an electron‐transport TiOx Ny layer, which is superior to conventional ZnO‐based devices with a PCE of 16.10%. Atomic‐layer‐deposited TiOx Ny ETL on a large area with a high uniformity may help accelerate the commercialization of emerging solar technologies.

Keywords

electron‐selective contacts organic solar cells passivating contacts silicon solar cell titanium oxynitride