銻化物高電子遷移率場效電晶體之閘極微縮製程發展與元件特性研究

Gate Shrinking and Device Charactrtization for Antimonide Based HEMTs Development

陳沛煜(Pei-Yu Chen)

指導教授 ： 蔡曜聰 ； 林恒光

國立中央大學/資訊電機學院/電機工程學系/碩士(2011年)

摘要

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。

關鍵字

砷銻化銦 ； 砷化銦 ； 次微米 ； 高電子遷移率場效電晶體 ； 電子束微影

並列摘要

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.

並列關鍵字

HEMT ； e-beam lithography ； submicron ； InAsSb ； InAs

參考文獻

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