RF performance enhancement in sub-<i>μ</i>m scaled β-Ga2O3 tri-gate FinFETs
Xinxin Yu, Hehe Gong, Jianjun Zhou, Zhenghao Shen, Fangfang Ren, Dunjun Chen, Xin Ou, Yuechan Kong, Zhonghui Li, Tangsheng Chen, Shulin Gu, Rong Zhang, Youdou Zheng, Jiandong Ye
Abstract
In this Letter, we report on the enhanced radio frequency (RF) performance in sub-micrometer scaled β-Ga2O3 tri-gate FinFETs. With a 200-nm-thick β-Ga2O3 bulk channel and a 0.35 μm gate length, the FinFETs exhibit an improved current-gain cutoff frequency of 5.4 GHz and a maximum oscillation frequency of 11.4 GHz, which are 20% and 58% improved with respect to the planar counterpart, respectively. The improved RF performance results from the enhanced gate control capability and the suppressed short-channel effects, as evidenced by the improved pinch-off characteristics, the improved transconductance, and the suppressed output conductance. It suggests that the tri-gate multi-fin architecture is a promising strategy to break the scaling limitation of the gate-channel aspect ratio toward high-performance β-Ga2O3 RF MOSFETs.