f_T为102GHz的蓝宝石衬底AlGaN/GaN高电子迁移率晶体管

An AlGaN /GaN High Electron Mobility Transistor with f_T of 102 GHz on sapphire substrate

研究了一款高性能的AlGaN/GaN高电子迁移率晶体管器件(HEMT),器件基于在蓝宝石衬底上外延生长的AlGaN/GaN异质结构HEMT材料,器件栅长为86 nm,源漏间距为0.8μm。电子束光刻实现T型栅和源漏,保证了器件小的栅长和高的对准精度。制备的器件显示了良好的直流特性和射频特性,在栅偏压为0 V时漏电流密度为995 mA/mm,在栅源电压Vgs为-4.5 V时,最大峰值跨导为225 mS/mm;器件的电流增益截止频率fT和最大振荡频率fmax分别为102和147 GHz。高fT值一方面得益于小栅长,另一方面由于小源漏间距减小了源漏沟道电阻。

A high-performance AlGaN/GaN high electron mobility transistor （HEMT） was re-searched, which grown on the sapphire substrate, and fabricated with a 86 nm gate length and a 0. 8 I.zmsource-to-drain distance. The T-shaped gate and source/drain regions were defined by the electron-beamphotolithography to reduce the gate length and increase the alignment accuracy. The device demonstratesgood DC and microwave characteristics. The drain current density is 995 mA/mm at a gate voltage of0 V, and a maximum peak extrinsic transconductance is 225 mS/mm at Vgs of -4.5 V. It is achievedthat a current gain cut-off frequencyfT of 102 GHz and a maximum oscillation frequency fmax of 147 GHz.The high fT value is owing to the small gate length and the low resistance with source and drain access region resulting from the short source-to-drain distance.