A Revised Growth Model for Transparent Conducting Ga Doped ZnO Films: Improving Crystallinity by Means of Buffer Layers

• Published in: Plasma processes and polymers 2015-08, Vol.12 (8), p.725-733
• Main Authors: Abduev, Aslan, Akmedov, Akhmed, Asvarov, Abil, Chiolerio, Alessandro
• Format: Article
• Language: English
• Subjects: Buffer layers; Direct current; Magnetron sputtering; Microstructure; Morphology; nucleation and growth; Resistivity; Solar energy; sputtering; Thin films; transparent conductive oxide; Zinc oxide
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.201400230

Ga‐doped ZnO (GZO) thin films are recently raising both scientific and industrial interests, due to the lack of natural resources. Indium is a crucial raw material, due to ITO modern touchscreen market. By doping ZnO with Ga conductive transparent thin films with various concentrations of dopant are prepared by DC magnetron sputtering from ceramic targets. It is shown how the Ga content plays an important role on the growth kinetics on an initial stage of the film formation and hence on the morphologies, microstructure and electrical properties of as‐grown GZO films. A mechanism explaining the role of Ga content on the nucleation process and the structure of growing films is proposed. Based on this mechanism, it is successfully demonstrated that the crystalline quality and hence the conductivity of GZO thin films can be improved by using a GZO buffer layer. Ga‐doped ZnO conductive transparent thin films (GZO) are prepared by DC magnetron sputtering. It is shown how the Ga content plays an important role on the growth kinetics on an initial stage of the film formation and hence on the morphologies, microstructure and electrical properties of as‐grown GZO films. A revised growth model is proposed and an application is successfully demonstrated to improve conductivity of GZO thin films by using a GZO buffer layer.