探討保護層對於非晶態銦鎵鋅氧化物薄膜電晶體穩定性之影響

Abstract

在本篇論文中，我們成功地藉由電漿輔助化學氣相沉積以及常壓退火爐管的方式在 α-IGZO薄膜電晶體上製作出無機保護層，但是在過程中發現無機材料對於通道層有著許多問題，故我們利用各式各樣的穩定性測試來分析無機保護層對於 α-IGZO的影響，諸如變溫量測、照光測試、閘極偏壓應力測試等，並且將其結果與有機保護層(Durimide 115A)元件以及沒有保護層的元件做比較。 透過變溫量測可以萃取出能態密度分佈，其結果顯示無機保護層元件的tail states高於有機保護層元件以及沒有保護層的元件。儘管無機保護層可以抑制閘極正偏壓應力測試中其他兩種元件所看到的奇異現象，但是其他穩定性測試的結果並不能看出無機保護層有著更多的正面影響。因此，我們成功地透過定量以及定性分析來比較各種元件的差異。

In this thesis, the α-IGZO TFTs passivated by an inorganic layer deposited by PECVD were fabricated and characterized. The influences of the passivation layers are explored through various stability tests, such as temperature-dependent measurements, illumination stressing, and gate bias stressing. The results are compared with the results of devices passivated by an organic material (Durimide 115A) and unpassivated devices. The density of states (DOS) distributions extracted from temperature-dependent measurements exhibit that there are much more tail states in the devices with an inorganic layer as compared with the splits without passivation. Even through the inorganic passivation layers can protect the devices from being affected and damaged by the species presenting in the surrounding environment, preparation of the passivation may introduce other side effects. For example, additional degradation would be resulted in after negative gate bias and illumination stressing with the capping of the inorganic materials.