Fabrication of Indium-Zirconium-Oxide Thin Film Transistors by Co-Sputtering and Optoelectronic Applications

Abstract

In my experiment I use the both targets of indium oxide and zirconium dioxide to co-sputter to fabricate the In-Zr-O thin film transistors and UV phototransistors The In-Zr-O thin film is analyzed by X-ray diffraction and atomic force microscope and we found that it is crystalline structure and has smooth surface which are beneficial to enhance the TFTs’ characteristics And then the In-Zr-O MSM UV photodetectors with Pt ohmic contact electrodes are realized It is found that changing the RF sputtering power for indium oxide target will transform the cut off wavelength and conductivity of the photodetectors Next it will focus on the investigation of the In-Zr-O thin film transistors We change the content of In2O3 in the thin film in order to fabricate Sample A to Sample I and it is found that Sample F owns good electrical property with SS of 0 43 (V/decade) μFE of 50 78 (cm2V?1s?1) and Ion/off of 9 98×105 Furthermore using 250-Watt Xenon lamp to emit 230–500 nm light will modulate the cut off wavelength of the UV phototransistors from 310 nm to 340 nm as the content of In2O3 is rising The photoresponsivity and UV-to-visible rejection ratio of the phototransistors for Sample F are 1 05 (A/W) and 2 2×104 Finally we fabricate bilayer In-Zr-O thin film transistors with double channel which is composed of Sample C as front channel and Sample D–F as back channel and we call them Sample J K and L Sample L shows better property with SS of 0 33 (V/decade) μFE of 58 16 (cm2V?1s?1) and Ion/off of 3 02×106 Compared with the TFTs with single layer structure the physical characteristics of the TFTs with bilayer structure is enhanced The cut off wavelength of the UV phototransistors rises to 325 nm–360 nm and the photoresponsivity and UV-to-visible rejection ratio of Sample L are 1 73 (A/W) and 3 2×102

Date of Award	2016 Jul 5
Original language	English
Supervisor	Shoou-Jinn Chang (Supervisor)