Implementation of High-Performance Solution-Processed Amorphous Indium–Gallium–Zinc–Oxide Thin-Film Transistors with Low Charge Traps by Microwave Heat Treatment of Low Thermal Budget

摘要

Herein, high-performance solution-processed amorphous indium–gallium–zinc–oxide (a-IGZO) thin-film transistors (TFTs) with low trap densities due to postdepositionannealing (PDA) are processed with a low-thermal-budget microwave(MW) heat treatment. To verify the MW effectiveness, the composition ratio ofa-IGZO thin films and the electrical characteristics of TFTs prepared by conventionalthermal annealing (CTA) are compared. An X-ray photoelectronspectroscopy (XPS) analysis reveals that MW annealing (MWA) improves the filmquality more effectively than CTA. a-IGZO TFTs treated by MWA or CTA arefabricated to evaluate their electrical characteristics. MWA is more effective thanCTA in improving the performance, such as hysteresis, subthreshold swing (SS),field effect mobility (μ_(FE)), and on/off current ratio (I_(on)/I_(off) ). MWA provides lowerinterfacial trap density (D_(it)) and volume trap density (N_t) than CTA. To evaluateinstability, the threshold voltage (V_(TH)) shift is monitored using positive andnegative gate-bias stress tests. MWA demonstrates better reliability than CTA. Inconclusion, high-performance solution-based a-IGZO TFTs can be implementedby lowering the charge traps in the a-IGZO channel using MWA.