Effect of deposition parameters on optical and electrical properties of ZnO-In2O3-SnO2 thin films

Abstract

A combinatorial study was carried out using a magnetron sputtering system to determine suitable ternary compositions of ZnO-In2O3-SnO2 (ZITO) thin films for optoelectronic applications. Samples were obtained on glass substrates via the co-sputtering of high purity oxide targets. Parameters such as the sputtering gas pressure, deposition time and substrate temperature were studied as the process variables and their effects on the composition, optical, and electrical properties of the thin films were examined in detail. The results have revealed that the samples deposited under a sputtering gas pressure of 10 mTorr and deposition time of 45 min in the Zn-rich region presented the best optical properties (max. 84%), whereas In-rich compositions exhibited better electrical properties (min. 14 & omega;/). More specifically, 61.7 at.% Zn, 31.4 at.% In, and 6.9 at.% Sn was determined as the most suitable ZITO composition for various optoelectronic applications. In addition, the in-crease in deposition temperature enhanced the optoelectronic properties of the thin film samples as well as their crystal quality.