氮掺杂非晶氧化铟锌薄膜晶体管的器件稳定性改善研究  

Impact of N_2-Doping on Reliability of Amorphous In ZnO∶N Thin Film Transistors

作　　者：严海[1] 蔡韵竹 张群[1] 谢汉萍[2] 

机构地区：[1]复旦大学材料科学系,上海200433 [2]台湾交通大学光电工程学系所

出　　处：《真空科学与技术学报》2015年第9期1054-1058,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(61071005;61136004);教育部博士点基金项目(2011007110010)

摘　　要：采用射频磁控溅射方法,在P型硅基片上制备了非晶掺氮氧化铟锌沟道层及其薄膜晶体管（a-IZO∶N-TFTs）器件,探讨了氮气对a-IZO∶N-TFTs性能和电学稳定性的影响。研究发现,当沉积过程中的氮气流量增加时,a-IZO∶N-TFTs的阈值电压（Vth）不断右移,说明氮气掺杂有效抑制了器件的载流子浓度。在对a-IZO∶N-TFTs进行0~5400 s的栅极正偏压应力测试中发现,通入4 m L/min（标准状态）的氮气能使Vth的变化量从3.77下降到0.72 V,表明氮气掺杂提高了a-IZO∶NTFTs的电学稳定性。然而,同时发现过量掺杂氮气也会造成新的氮相关缺陷从而降低器件的稳定性。The N2-doped amorphous InZnO （a-IZO：N） thin film transistor （TFT） were fabricated by RF magnetron sputtering of ]ZO target on substrate of p-type Si. The influence of the N2 flow rate on the electronic structures, character- istics and electrical reliability of the a-IZO： N-TFT was investigated with X-ray photoelectron spectroscopy and convention- al tools. The results show that the N2-doping significantly affects the characteristics and electrical reliability of a-IZO- TFT. To be specific, as the N2 flow rate increased to 4 mL/min, the TFT＇ s threshold voltage （Vth） shifted from - 22.76 to - 14.46 V, indicating that N2-doping strongly suppressed the carrier concentration; and in the positive gate bias stress （PBGS） test from 0 to 5400 s, the A Vth of the a-IZO： N-TFT, doped at 4 mL/min of N2, was found to decrease from 3.77 to 0.72 V, revealing that the optimized N2-doping improved the electrical reliability. However, excessive Na-doping lowers the reliability, possibly because of increased N2-indueed defects.

关 键 词：薄膜晶体管 IZO 氮气掺杂 稳定性 

分 类 号：TN321.5[电子电信—物理电子学]