Title :
AlGaN/GaN HEMTs on SiC with fT of over 120 GHz
Author :
Kumar, Vipin ; Lu, W. ; Schwindt, R. ; Kuliev, A. ; Simin, G. ; Yang, J. ; Asif Khan, M. ; Adesida, I.
Author_Institution :
Dept. of Electr. & Comput. Eng., Illinois Univ., Urbana, IL, USA
Abstract :
AlGaN/GaN high electron mobility transistors (HEMTs) grown on semi-insulating SiC substrates with a 0.12 μm gate length have been fabricated. These 0.12-μm gate-length devices exhibited maximum drain current density as high as 1.23 A/mm and peak extrinsic transconductance of 314 mS/mm. The threshold voltage was -5.2 V. A unity current gain cutoff frequency (fT) of 121 GHz and maximum frequency of oscillation (fmax) of 162 GHz were measured on these devices. These fT and fmax values are the highest ever reported values for GaN-based HEMTs.
Keywords :
III-V semiconductors; MOCVD; aluminium compounds; electron beam lithography; gallium compounds; high electron mobility transistors; isolation technology; millimetre wave field effect transistors; rapid thermal annealing; semiconductor device metallisation; short-circuit currents; sputter etching; wide band gap semiconductors; 121 GHz; 162 GHz; AlGaN-GaN; MOCVD; T-shaped gates; electron-beam lithography; high electron mobility transistors; maximum drain current density; maximum frequency of oscillation; mesa-isolation; metallization; ohmic contacts; peak extrinsic transconductance; rapid thermal annealing; reactive ion etch; semi-insulating substrates; short-circuit current gain; threshold voltage; transfer characteristics; unity current gain cutoff frequency; Aluminum gallium nitride; Current density; Current measurement; Cutoff frequency; Gallium nitride; HEMTs; MODFETs; Silicon carbide; Threshold voltage; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2002.801303
