Effects of low doping concentration on interconnected microstructural ZnO:Al thin films prepared by the sol-gel technique

¹ Department of Applied Physics, University of Electronic Science and Technology of China, Chengdu 610054, P.R. China
² Department of Physics, Zhanjiang Normal College, Zhanjiang 524048, P.R. China
³ International Center for Material Physics, Chinese Academy of Sciences, Shengyang 110015, P.R. China
⁴ School of Microelectronics and Solid-state Electronics, University of Electronics Sciences and Technology of China, Chengdu 610054, P.R. China

Corresponding author: xiaotaozu@yahoo.com

Received: 5 March 2006
Revised: 18 April 2006
Accepted: 19 April 2006
Published online: 2 September 2006

Abstract

Interconnected microstructural ZnO:Al thin films with low doping concentration (Al/Zn ≤1%) were deposited on (0001) sapphire substrates by the sol-gel technique. The effects of low doping concentration on the structural, optical and electrical properties of the films were investigated. Scanning electron microscope (SEM), X-ray diffraction (XRD), photoluminescence (PL), and four-point probe method were used to characterize the structural, optical and electrical properties. We found that with increasing the dopant concentration the interconnected thread becomes thinner, the (002) diffraction peak and the near band edge (NBE) emission are enhanced while the deep level emission (DLE) and the resistivity are decreased.