Ruan Dun-Bao, Liu Po-Tsun, Chiu Yu-Chuan, Kuo Po-Yi, Yu Min-Chin, Gan Kai-Jhih, Chien Ta-Chun, Sze Simon M
Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University Hsinchu 30010 Taiwan.
Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University Hsinchu 30010 Taiwan
RSC Adv. 2018 Feb 12;8(13):6925-6930. doi: 10.1039/c7ra13193c. eCollection 2018 Feb 9.
This study investigates the electrical characteristics and physical analysis for an amorphous tungsten-doped indium-zinc oxide thin film transistor with different backchannel passivation layers (BPLs), which were deposited by an ion bombardment-free process. A 10 times increase in mobility was observed and attributed to the generation of donor-like oxygen vacancies at the backchannel, which is induced by the oxygen desorption and Gibbs free energy of the BPL material. The mechanism was well studied by XPS analysis. On the other hand, a HfO gate insulator was applied for the InWZnO TFT device to control the extremely conductive channel and adjust the negative threshold voltage. With both a HfO gate insulator and a suitable BPL, the InWZnO TFT device exhibits good electrical characteristics and a remarkable lifetime when exposed to the ambient air.
本研究对采用无离子轰击工艺沉积的具有不同背沟道钝化层（BPL）的非晶掺钨铟锌氧化物薄膜晶体管进行了电学特性研究和物理分析。观察到迁移率提高了10倍，这归因于背沟道处类施主氧空位的产生，这是由BPL材料的氧脱附和吉布斯自由能所诱导的。通过XPS分析对该机制进行了深入研究。另一方面，将HfO栅极绝缘体应用于InWZnO TFT器件，以控制极导电沟道并调整负阈值电压。同时具备HfO栅极绝缘体和合适的BPL时，InWZnO TFT器件在暴露于环境空气时表现出良好的电学特性和显著的寿命。
