非晶铟镓锌氧化物薄膜晶体管关键工艺研究

Key Process Research of Indium Gallium Zinc Oxide Thin Film Transistor with Etch Stop Layer

为优化金属氧化物薄膜晶体管(IGZO-TFT)的特性,采用射频磁控溅射法沉积IGZO薄膜作为半导体活性层,制备出具有刻蚀阻挡层(Etch stop layer,ESL)结构的IGZO TFT,在2.5 G试验线上研究了IGZO沉积过程中O_2浓度、IGZO沉积后N_2O等离子体处理、ESL的制备温度和ESL沉积过程中N_2O/Si H4的比例等关键工艺条件对IGZO TFT的阈值电压(Vth)的影响。实验结果表明:IGZO沉积过程中O_2浓度的增加、IGZO沉积后N_2O等离子体处理和ESL制备温度的降低会导致IGZO TFT的V_(th)正偏移。

In order to improve the performance of Indium Gallium Zinc Oxide Thin Film Transistor, IGZO-TFT with etch-stop layer was prepared in 2.5G experimental line. The effects of O2 concentration during IGZO deposition, N2O plasma treatment, the temperature of ESL deposition and the N2O/SiH4 ratio on the IGZO TFT F th were systemically studied. T h e results show that the F th would shift to positive position as the increasing of O2 concentration, N2O plasma treatment, and the decreasing of ESL deposition temperature.