Photovoltaic responses of ZnO/Si heterojunctions synthesized by sol-gel method

¹ Laboratory of Optic Sensing and Detecting Technology, China University of Petroleum, Beijing 102249, P.R. China
² State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, P.R. China
³ International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, P.R. China

^a e-mail: zhk@cup.edu.cn

Received: 10 January 2010
Revised: 5 August 2010
Accepted: 15 March 2011
Published online: 21 July 2011

Abstract

ZnO/Si heterojunctions were prepared by the sol-gel method and hexagonal polycrystalline wurtzite structures with pores were observed by a field emission scanning electron microscope. The steady photovoltage properties of ZnO/Si heterojunctions were obtained under the illumination of a 532 nm continuum solid state laser with a 50 Hz chopper. In addition ns photoresponse signals were found when the samples were excited by a ps pulsed laser at room temperature. A possible mechanism was proposed to describe the photovoltaic process in the ZnO/Si heterojunction.