Preparation And Temperature Characteristics Of A-IGZO Thin Film Transistor

In order to satisfy the exploration of aerospace,industrial fuel turbines,oil and natural gas industries,to satisfy the stability of sensor testing and reading system in high temperature environment,and to produce electronic devices that can meet the stability of work in extreme environment is a difficult problem to be solved urgently.Conventional power systems cannot operate at high temperatures because the PN junction of semiconductor silicon fails above 150 °C.SiC is reported as a replaceable high temperature semiconductor material.The operating temperature of SiC devices can reach higher temperatures,but there is no report on the integration of SiC devices with other high temperature resistant substrates such as ceramic substrates.According to the above application requirements,a thin film transistor(TFT)device based on sapphire Al2O3 is proposed.The oxide semiconductor material a-IGZO was selected and tested at 293-523 K,and a TFT-based digital logic gate circuit was fabricated for waveform verification.It provides the basis for the high temperature verification of subsequent digital logic gate circuits.The main research contents of this paper are as follows:1.Firstly,the micro-structure and conductive mechanism of a-IGZO oxide semiconductor,as well as the structure and working principle of thin film transistor are introduced.A thin film transistor structure with bottom gate top contact structure is proposed for testing at high temperature.2.TFT was fabricated on sapphire Al2O3 substrate during the preparation process,and tested in the temperature range of 293-523 K.By analyzing the output characteristic and transfer characteristic curve and extracting the parameters,the relationship between the characteristic parameters of the device and the temperature is obtained,and the theoretical analysis is carried out,which provides the basis for the high temperature verification of the subsequent digital logic gate circuit.3.Circuits such as NAND and NOR gates are some of the basic building blocks in modern digital integrated circuits.By fabricating inverters,NAND and NOR gates consisting of multiple thin film transistors and verifying them at different frequencies,temperatures and input waveforms,it is concluded that the above circuit returns the correct logic output signal based on the corresponding input logic in high temperature environment,which enables us to further explore more complex digital circuits through hybrid circuit design.