High‐frequency InAlN/GaN HFET with fmax over 400 GHz. Issue 12 (1st June 2018)

• Record Type: Journal Article
• Authors: Fu, Xing‐Chang; Lv, Yuanjie; Zhang, Li‐Jiang; Zhang, Tong; Li, Xian‐Jie; Song, Xubo; Zhang, Zhirong; Fang, Yulong; Feng, Zhihong
• Is Part Of: Electronics letters. Volume 54:Issue 12(2018)
• Page Start: 783
• Page End: 785
• Publication Date: 2018-06-01
• Subjects: gallium compounds -- ohmic contacts -- III‐V semiconductors -- indium compounds -- wide band gap semiconductors -- aluminium compounds -- electron density -- semiconductor heterojunctions -- high electron mobility transistors -- UHF power amplifiers -- millimetre wave field effect transistors -- electron beam lithography -- submillimetre wave transistors; high maximum oscillation frequency -- electron density -- short‐channel effects -- total ohmic resistance -- G‐band power‐amplifier application -- lateral dimension scaling -- GaN cap layer -- ultra‐thin InAlN‐GaN heterostructure field‐effect transistors -- high‐frequency InAlN‐GaN HFET -- nonalloyed regrown ohmic contacts -- virtual source‐to‐drain distance -- T‐shaped gate -- self‐aligned e‐beam lithography -- peak extrinsic transconductance -- frequency 140.0 GHz to 220.0 GHz -- size 3.0 nm -- size 600.0 nm -- size 40.0 nm -- resistivity 0.13 ohmm -- InAlN‐GaN; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2018.0247
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : Ultra‐thin InAlN/GaN heterostructure field‐effect transistors (HFETs) having high maximum oscillation frequency ( f max ) are fabricated by scaling lateral dimensions. A 3 nm GaN cap layer is adopted to reduce the electron density and suppress the short‐channel effects. Non‐alloyed regrown n + ‐GaN ohmic contacts with total ohmic resistance ( R tot ) of 0.13 Ω.mm is also introduced into the device, in which the virtual source‐to‐drain distance is 600 nm. T‐shaped gate with 40 nm length is formed in the centre of the source‐to‐drain region by self‐aligned e‐beam lithography. The peak extrinsic transconductance ( g m ) reaches 956 mS/mm. Most of all, a high f max of 405 GHz is obtained, which is the highest value among the reported InAlN/GaN HFETs. These obtained results mean that the InAlN/GaN HFETs having reliability should be still suitable for G‐band (140–220 GHz) power‐amplifier application with further optimisation.