Effect of Ag doping on the electrical properties of thermally deposited CdS–La2O3 TFTs

Abstract

In this article, we have reported the fabrication of CdS thin film transistors (TFTs) doped with Ag by thermal evaporation technique on chemically cleaned glass substrates using multiple pumps down process. High-k rare earth oxide La2O3 is used as gate dielectric in CdS TFTs. Some important electrical parameters have been evaluated using Weimer's model. The electrical parameters are compared with the parameters of undoped CdS TFTs. The Ag-doped CdS TFTs exhibit a high mobility of 6.1 cm2 V−1 s−1 than that of the undoped CdS TFTs, mobility of which is found as 6.25 × 10−2 cm2 V−1 s−1. The TFTs also exhibit low threshold voltage. Both Ag-doped and undoped TFTs are characterised using Levinson et al. model.