0.5μm栅长HfO_2栅介质的GaN金属氧化物半导体高电子迁移率晶体管  

A High Electron Mobility Transistor of GaN Metal Oxide Semiconductor with 0.5μm Gate Length Employing HfO_2 as Gate Dielectric

作　　者：韩克锋[1] 王创国[1] 朱琳[1] 孔月婵[1] 

机构地区：[1]中国电子科技集团公司第五十五研究所,南京210016

出　　处：《西安交通大学学报》2017年第8期72-76,共5页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(61474101)

摘　　要：为了抑制GaN高电子迁移率晶体管(HEMT)的栅极漏电,提出了一种0.5μm栅长的GaN金属氧化物半导体(MOS)高电子迁移率晶体管结构。该结构采用势垒层部分挖槽,并用高介电常数绝缘栅介质的金属氧化物半导体栅结构替代传统GaN HEMT中的肖特基栅。基于此结构制备出一种GaN MOSHEMT器件,势垒层总厚度为20nm,挖槽深度为15nm,栅介质采用高介电常数的HfO_2,器件栅长为0.5μm。对器件电流电压特性和射频特性的测试结果表明:所制备的GaN MOSHEMT器件最大电流线密度达到0.9 A/mm,开态源漏击穿电压达到75 V;与GaN HEMT器件相比,其栅极电流被大大压制,正向栅压摆幅可提高10倍以上,并达到与同栅长GaN HEMT相当的射频特性。A high electron mobility transistor of GaN metal oxide semiconductor with 0.5μm gate length （MOSHEMT） is proposed to suppress the gate leakage of GaN high electron mobility transistor （HEMT）.A partially etched barrier structure is employed,and the structure of metaloxide-semiconductor （MOS） gate with a high dielectric constant dielectric is used to replace the traditional GaN-HEMT Schottky gate.A GaN MOSHEMT is fabricated based on the proposed structure.The total thickness of the barrier layer is 20 nm,and the depth of the barrier trench is 15 nm.The gate dielectric uses the HfO2 with high dielectric constant,and the gate length is 0.5 μm.Tests of current-voltage characteristic and radio frequency characteristic of the proposed device show that the maximum current density of the device is 900 A/mm,and the source-drain breakdown voltage is 75 V.A comparison with traditional GaN HEMTs shows that the GaN MOSHEMT greatly suppresses the gate current,its forward gate swing voltage is about ten times higher,and its radio frequency characteristic is comparable to that of the traditional GaN HEMTs with same gate length.

关 键 词：高电子迁移率晶体管 氮化镓 栅电流 射频特性 

分 类 号：TN305.2[电子电信—物理电子学] TN325.3