銻化物系列材料由於擁有卓越的載子傳輸特性，因此非常適合應用於低功率及高速度的電子元件。在本論文中成功製作出高頻應用之高效能砷化銦/銻化鋁高電子遷移率電晶體，並且做了深入的分析與探討。
首先為了提升高電子遷移率電晶體之特性，利用電子束微影系統發展縮小閘極線寬的技術。在電子束微影製程發展中利用ZEP/LOR/ZEP阻劑來取代傳統PMMA/P(MMA-MAA)阻劑所能達到最小的閘極線寬為35nm。另外，藉由減少源極與汲極間距來進一步提升高電子遷移率電晶體的性能。因此發展了幾種因應元件尺寸微縮之製作方式，包括標準製程、T型閘極自我對準製程及掘入式閘極製程。其中標準製程元件擁有最好的電性表現，在閘極長度Lg=0.2μm，源極與汲極間距LDS=1.5μm的元件上，汲極飽和電流於汲極偏壓VDS=0.4V時為733mA/mm，轉導特性gm=1520mS/mm，高頻增益部分電流增益截止頻率fT=105GHz與功率增益截止頻率fMAX=132GHz。此元件微縮製程大幅改善了直流特性與高頻特性，且電流增益截止頻率相較於閘極長度為2μm的元件提升了10倍。

Sb-based HEMTs have great promise for low-power and high-speed applications because of their superior carrier transport properties. In this thesis, high-performance InAs/AlSb high-electron-mobility transistors have been fabricated and characterized for high-frequency applications.
Device performance was successfully improved by shrinking the gate length using electron beam lithography system. Traditional PMMA/ P(MMA-MAA) e-beam resists were replaced by ZEP/LOR/ZEP e-beam resists and a smallest gate length of 35nm was succesfully achieved. In addition, devices with small source-to-drain spacing were fabricated to promote high-frequency performance of the HEMTs. Several different methods were developed to narrow down device dimension, including standard process, self-aligned process and gate recess process. A standard device with 0.2μm gate length and 1.5μm source-to-drain spacing showed the best DC and RF performance. Maximum drain current of 733mA/mm and extrinsic transconductance of 1520mS/mm were obtained at a drain voltage of 0.4V. A current gain cut-off frequency of 105GHz and a power gain cut-off frequency of 132GHz were successfully demonstrated. The current gain cut-off frequency of a 0.2μm-gate-length device was raised 10 times compared with a 2μm-gate-length device.

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