Study Of CuNiSnO And ZnMgSnO Amorphous Oxide Semiconductor Thin Films And Their Pplication In Thin Film Transistors

This thesis contains two parts:the first part is the preparation of p-type AOS thin films and property research.The second part is the fabrication of n-type amorphous oxide semiconductor(AOS)films and its application in thin film transistors(TFTs)as active layers.Transparent and flexible electronic device is the future direction of development,while TFTs devices is an essential part for this field.TFTs fabricated with amorphous oxide semiconductors have shown promising prospect to be used in transparent and flexible electronic devices for its low-temperature deposition,compatibility with flexible organic substrates and high transparency in the range of visible-light wavelength,which is a research hotspot at present.Specifically,the amorphous InGaZnO system has attracted considerable attention and been used in industrial products several years ago.However,indium and gallium are very expensive due to their rare reserves.With a view to sustainable development,finding new materials to replace In and Ga is very necessary.Moreover,p-type TFTs is an important part of logic circuit,so it is vital to make p-type AOS TFTs used in transparent and flexible logic circuit come ture.For reasons above,on the one hand,we induce a new p-type AOS,CuNiSnO,and take research of its properties further;on the other hand,we propose the amorphous ZnMgSnO system to make a substitution of amorphous InGaZnO system as the active layers used in n-type AOS TFTs.The conclusions are summarized as follows:1 The CNTO thin films are fabricated by pulsed laser deposition at different temperatures.The CNTO films are amorphous with elements distributed uniformly,and all have smooth surface.They are transparent with average visible-light transmittance of 80%.It is revealed that all the films have p-type signals,with the highest hole concentration of～4×1015 cm-3 and a resistivity of～8×103 Ω·cm for that grown at 100 ℃.2.Amorphous p-type TFTs are fabricated with CuNiSnO films grown at 100 ℃as active layers.It has exhibited an on/off ratio of～103 and field effect mobility of 0.0764 cm2·V-1·S-1.Although there is still a big gap compared with n-type AOS TFTs,it is significant for research of p-type AOS TFTs.3.n-type AOS,ZnMgSnO is fabricated by solution spinning,and the effect on the material properties with variation of Mg content is studied.It can be find that all the films are amorphous with high transparency in the range of visible-light.The Vo concentration is decreasing with the increasing of Mg content,which leads to the reduction of carrier concentration,so Mg serves the same purpose in ZnMgSnO as Ga in InGaZnO.4.TFT devices are fabricated with ZnMgSnO films as active layers.The device fabricated with ZMTO(0.5)as active layer exhibits an field effect mobility of 0.083 cm2·V-1·S-1,on/off ratio of～3×105 and Vth of 0.513 V.The research of this new n-type AOS makes an instructive exploration on replacing InGaZnO system.