Preparation And Performance Control Of Indium Gallium Zinc Oxide Thin Film Transistor

Compared with amorphous silicon thin film transistors,thin film transistors using indium gallium zinc oxide(IGZO)thin film materials as the active layer have the advantages of high carrier mobility,large area preparation,good uniformity,and stable device performance.It is compatible with the current amorphous silicon thin film transistor process and is an ideal material in the field of flat panel displays.At the same time,high-gain composite optoelectronic devices based on IGZO thin-film transistors are also one of the hot spots in the field of optoelectronic detection research in recent years.This paper mainly studies the controllable preparation of IGZO thin films,the processing,performance optimization,surface modification and modification of IGZO thin film transistors,focusing on the following aspects:Firstly,using IGZO alloy target as the raw material,IGZO thin film is prepared by radio frequency magnetron sputtering method.Through oxygen partial pressure adjustment and growth time control,IGZO thin films with different oxygen component content and thickness are controllably prepared.Secondly,the IGZO thin film transistor with back-gate structure is designed and implemented.The effects of oxygen content,insulating layer thickness,channel width-to-length ratio and IGZO film thickness on the performance of IGZO thin film transistor are systematically studied.Conditions for IGZO thin film transistors with threshold swing,low threshold voltage,and high current switching ratio.The photoelectric response characteristics of IGZO thin film transistors under different excitation wavelengths and light irradiation are studied,the mechanism of the photoelectric response of IGZO thin film transistors is analyzed and a method to study the defect states of IGZO thin film transistors by optical methods is obtained.In addition,the stability of IGZO thin film transistors is studied.Finally,the performance optimization of IGZO thin film transistors by annealing is studied;the defect state in IGZO thin films is changed by gas plasma,and then the adjustment of threshold voltages and other parameters of IGZO thin film transistors is studied.The enhanced and depleted IGZO thin film transistors are realized by oxygen,nitrogen and hydrogen plasmas,respectively;the method of preparing In Sb quantum dots in mid-wave infrared response by top-down mechanical grinding is studied.The preliminary realization of In Sb quantum dots with absorption spectrum in the middle wave laid a foundation for the construction of high-gain optoelectronic devices based on quantum dots/IGZO thin film transistors.