改變閘極電壓量測波形以探討非晶氧化銦鎵鋅薄膜電晶體之電滯機制

Abstract

非晶銦鎵鋅氧化物薄膜晶體管具有許多的優點，使之被期待可以應用在透明電子產品、有機發光二極體顯示器和光偵測器上，然而，在應用上，電滯的現象是一項重要的議題。傳統的研究是用電源量測單元的預設條件執行雙向掃取閘極電壓，其掃取速度會對應於量測電流值的大小而改變。因此，我們提出新的控制閘極電壓的量測方法，可避免量測中較長的積分時間造成偏壓的問題。我們使用快速取樣和脈衝量測方式，分別在不同的偏壓時間與掃取速度下來觀察汲極電流，以釐清電滯的機制。我們也討論了光強和溫度的效應，並基於其結果和分析，提出了氧空缺的模型來解釋電滯的反應時間。這在元件於其電路應用的驅動時是很重要的課題。

The amorphous indium-gallium-zinc-oxide thin-film transistors can be expected to be applied in the transparent electronics, organic light emission displays and photo sensor for its many advantages. However, the phenomenon of hysteresis is a critical issue in the application. It is conventionally studied by double sweeping gate voltage with the default setup of the source measure units, which sweeping speed may vary with the current level. Therefore, the new measurement method of controlled gate voltage sweeping is proposed. It can avoid the stress issue for longer integration time in the measurement. The sampling and pulse measurement methods are used to observe the drain current with different stress time and under the different sweeping gate voltage to clarify the mechanism of hysteresis, respectively. Effects of temperature and light intensity are also discussed. Based on the results and the analysis, the model of oxygen vacancies is proposed to explain the response time of hysteresis, which would be important for the devices to be driven in their circuit application.