Fabrication and optimization process of p-type Li: ZnO oxide semiconductor

Li-doped ZnO films with various Li contents (0.1-0.8 mol%) were prepared by pulsed DC sputtering system with soft-chemical methods synthesized LixZn1-xO1-x/2 targets. It has been investigated that the structural and electrical properties of deposited films depended on the content of doping in target. We observed p-type conduction with low resistivity for 0.1-0.3 mol% and n-type with decreased resistivity for 0.6-0.8 mol% of Li content on the film. These varieties of electrical resistivity and conductivity are suggested as the role of domination between substitutional acceptor Li-Zn and compensation defects of Li-Zn-Li-i complex along with increasing Li doping amounts on the film, i.e. Li-Zn for p-type and Li-Zn-Li-i for n-type. We also investigate the role of sputtering variables, such as substrate temperature, sputtering power and Ar flow rate, to optimize our sputtering process. Finally, Li(x)Zn(1-x)O(1-x/2)p-n homojunction diode is demonstrated to confirm stability of the p-type conduction characteristic in our deposited Li: ZnO film. (C) 2014 Elsevier B. V. All rights reserved.