Simulation study of InAlN/GaN high-electron mobility transistor with AlInN back barrier

• Published in: Chinese physics B 2017-10, Vol.26 (10), p.433-437
• Main Author: 韩铁成 赵红东 杨磊 王杨
• Format: Article
• Language: English
• Subjects: HEMT器件; 不连续性; 功率增益; 势垒层; 器件模拟; 截止频率; 短沟道效应; 高电子迁移率晶体管
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/26/10/107301

In this work, we use a 3-nm-thick Al0.64In0.36N back-barrier layer in In0.17Al0.83N/GaN high-electron mobility transistor （HEMT） to enhance electron confinement. Based on two-dimensional device simulations, the influences of Al0.64In0.36N back-barrier on the direct-current （DC） and radio-frequency （RF） characteristics of InAlN/GaN HEMT are investigated, theoretically. It is shown that an effective conduction band discontinuity of approximately 0.5 eV is created by the 3-nm-thick Al0.64In0.36N back-barrier and no parasitic electron channel is formed. Comparing with the conventional InAlN/GaN HEMT, the electron confinement of the back-barrier HEMT is significantly improved, which allows a good immunity to short-channel effect （SCE） for gate length decreasing down to 60 nm （9-nm top barrier）. For a 70-nm gate length, the peak current gain cut-off frequency （fT） and power gain cut-off frequency （fmax） of the back-barrier HEMT are 172 GHz and 217 GHz, respectively, which are higher than those of the conventional HEMT with the same gate length.