Ultrasonic Treatment-Induced Enhancement of Mechanical and Electrical Properties in InGaZnO Thin-Film Transistors

The increasing interest in display electronics necessitates the reduction of mechanical stress while ensuring high performance. In this study, we propose a straightforward approach, namely ultrasonic treatment for reducing stress and enhancing the performance of amorphous InGaZnO (a-IGZO) thin film transistors (TFTs). IGZO-TFTs fabricated under 180 min ultrasonic treatment conditions demonstrate exceptional switching characteristics, showing a saturation mobility (µ_sat) of 22.04 cm²·V⁻¹·s⁻¹, and a threshold voltage (V_th) of 0.21 V. Moreover, the average Young’s modulus on the surface of IGZO thin films decreases to 3.04 GPa. When subjected to bending simulation with a curvature radius of 0.5 mm, TFT devices exhibit approximately 10 MPa reduction in stress at the interface between the active layer and insulating layer. We propose that ultrasonic treatment promotes the formation of metal-oxygen bonds in a-IGZO films through atomic relaxation, reducing the formation of hydrogen-oxygen bonds and thereby improving electrical and mechanical properties.