溶胶凝胶法制备高性能锆铝氧化物作为绝缘层的薄膜晶体管

Solution-processed high performance HIZO thin film transistor with AZO gate dielectric

本文采用溶胶凝胶法制备了锆掺杂铝氧化物(锆铝氧化物)和铪铟锌氧化物薄膜,并用于制造薄膜晶体管的绝缘层和有源层.锆铝氧化物绝缘层具有较高的介电常数,其相对介电常数为19.67,且薄膜表面光滑,致密,其表面粗糙度仅为0.31 nm.获得的薄膜晶体管具备良好的器件性能,当器件宽长比为5时,器件的饱和迁移率为21.3 cm2/V·s,阈值电压为0.3 V,开关比可以达到4.3×107,亚阈值摆幅仅有0.32 V/dec.

Hafnium indium zinc oxide （HIZO） thin film transistors with zirconium aluminum oxide （AZO） gate dielectric were fabricated by solution-process. The HIZO and AZO oxide thin films have smooth surfaces with root-mean-square roughness of 0.62 nm and 0.35 nm respectively. The thin film transistor with channel length = 6 μm and the ratio of width/length =5 exhibits a high saturation field-effect mobility of 21.3 cm2/V·s, a low threshold voltage of 0.3 V, a high on-off ratio of 4.3×107 and a small subthreshold swing of 0.32 V/dec. And these properties of TFT may be impacted by highly-coherent and low trapping states interface between the AZO dielectric and HIZO semiconductors.