Influence of thermal annealing on the electrical characteristics of doped zinc oxide thin film transistors

摘要

Thin film transistors with zinc oxide doped by indium and gallium (IGZO) as the semiconductor layer were investigated. Two type transistors were prepared by different conditions. The first was annealing IGZO film before depositing Ni source-drain electrode (Device A); the second was annealing IGZO film after depositing Ni source-drain electrodes (Device B). It is found that Device A shows better performances with a field-effect mobility of 2.8cm2/Vs, a current on/off ratio of 106, and a threshold voltage of about 10V. However, Device B shows poor electric performances with a field-effect mobility of 0.3cm2/Vs, a current on/off ratio of 104, and a threshold voltage of about 30V.