Homojunction structure amorphous oxide thin film transistors with ultra-high mobility

Amorphous oxide semiconductors(AOS)have unique advantages in transparent and flexible thin film transistors(TFTs)applications,compared to low-temperature polycrystalline-Si(LTPS).However,intrinsic AOS TFTs are difficult to obtain field-effect mobility(μFE)higher than LTPS(100 cm^(2)/(V·s)).Here,we design ZnAlSnO(ZATO)homojunction structure TFTs to obtainμFE=113.8 cm^(2)/(V·s).The device demonstrates optimized comprehensive electrical properties with an off-current of about1.5×10^(-11)A,a threshold voltage of–1.71 V,and a subthreshold swing of 0.372 V/dec.There are two kinds of gradient coupled in the homojunction active layer,which are micro-crystallization and carrier suppressor concentration gradient distribution so that the device can reduce off-current and shift the threshold voltage positively while maintaining high field-effect mobility.Our research in the homojunction active layer points to a promising direction for obtaining excellent-performance AOS TFTs.

Room-Temperature Processed Amorphous ZnRhCuO Thin Films with p-Type Transistor and Gas-Sensor Behaviors

We examine an amorphous oxide semiconductor(AOS)of ZnRhCuO.The a-ZnRhCuO films are deposited at room temperature,having a high amorphous quality with smooth surface,uniform thickness and evenly distributed elements,as well as a high visible transmittance above 87%with a wide bandgap of 3.12 eV.Using a-ZnRhCuO films as active layers,thin-film transistors(TFTs)and gas sensors are fabricated.The TFT behaviors demonstrate the p-type nature of a-ZnRhCuO channel,with an on-to-off current ratio of^1×10^3 and field-effect mobility of0.079 cm^2 V^-1s^-1.The behaviors of gas sensors also prove that the a-ZnRhCuO films are of p-type conductivity.Our achievements relating to p-type a-ZnRhCuO films at room temperature with TFT devices may pave the way to practical applications of AOSs in transparent flexible electronics.