具有漸進式障壁層結構氮化鋁鎵/氮化鋁/氮化鎵/矽之金屬-氧化物-半導體異質結構場效電晶體研製

Abstract

中文摘要 本專題旨在應用超音波噴霧熱解沉積技術(ultrasonic spray pyrolysis deposition)研製以氧化鋁為電介質之漸進式障壁層(Graded-Barrier)製成AlxGa1-xN/AlN/GaN/Si (x = 0.22~0.3)的金屬-氧化物-半導體異質結構場效電晶體(MOS-HFET)與常見障壁層(Conventional-Barrier) Al0.26Ga0.74N/AlN/GaN/Si MOS-HFET以及蕭特基閘極HFET裝置做比較。藉由漸進式障壁層可使介面品質問題與增加蕭特基能障高度問題同時得到解決。符合成本效益的超音波噴霧熱解沉積(USPD)科技目前常用於製作MOS-HFET的表面鈍化與沉積高介電係數(high-K)氧化鋁閘極絕緣層。 在此專題中，將廣泛地討論到藉由量測裝置表現出來的特性，包括外質轉導(gm,max)、閘極電極擺幅(GVS)、最大汲源極電流密度(IDS,max)、崩潰電壓、開關電流比率(Ion/Ioff)、高頻、次臨界擺幅(SS)與功率特性。

Abstract A study of a novel Al2O3 dielectric gradient barrier (GB) AlxGa1-xN / AlN / GaN / Si (x = 0.22~0.3) metal oxide semiconductor heterostructure field effect transistor (MOSHFET) through ultrasonic spray pyrolysis deposition(USPD) technique compared with a conventional-barrier (CB) Al0.26Ga0.74N / AlN / GaN / Si MOS-HFET and the Schottky gate HFET devices. The gradient barrier (GB) AlxGa1-xN was designed to improve interface quality and increase the Schottky barrier height simultaneously. The cost effective technique commonly applied to make surface passivation and deposit the high-k Al2O3 gate-dielectric on the AlGaN barrier. Comprehensive device performances, including maximum external transconductance (gm,max), gate voltage swing (GVS) linearity, maximum drain-source current density (IDS,max), breakdown voltage, on/off current ratio (Ion/Ioff), high frequency, subthreshold swing (SS) and power performance.