The Variation of Optical Band Gap for ZnO:In Films Prepared by Sol-Gel Technique

Advances in Materials Science and Engineering

Research Article

Wei Zhang²  Hua Liu¹  Guomei Tang¹ 

[1] School of Mathematics and Computer Science Institute, Northwest University for Nationalities, Lanzhou 730030, China, xbmu.edu.cn;School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China, lzu.edu.cn

Others  :  1299003
DOI  :  10.1155/2013/348601

 received in 2013-04-03, accepted in 2013-10-27,  发布年份 2013

【 摘 要 】

ZnO:In films with different concentrations (0–5 at.%) are successfully synthesized on quartz substrates using sol-gel technique. The structure, morphology, and optical properties of ZnO:In films are investigated by X-ray diffraction, atomic force microscopy, and UV-visible spectrophotometer. It is found that all the films with columnar structural morphology grow along the preferred [001] orientation and the incorporation of indium can improve the crystallinity of ZnO films. The transmittance of the films is about 80% in the visible range. A change of the optical absorption edge from blue shift to red shift is observed for ZnO:In films as the doping concentration increases, which means that the optical band gap first increases and then decreases. The blue shift is due to the Burstein-Moss effect. The sharp jump of the absorption edge from blue-shift to red shift is ascribe to the band gap narrowing caused by the merging of the donor and conduction bands of ZnO:In at high doping concentration.

【 授权许可】

CC BY   
Copyright © 2013 Guomei Tang et al. 2013

【 图 表 】

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