Title :
An Al/sub 0.3/Ga/sub 0.7/N/GaN undoped channel heterostructure field effect transistor with Fmax of 107 GHz
Author :
Li, R. ; Cai, S.J. ; Wong, L. ; Chen, Yuanfeng ; Wang, K.L. ; Smith, R.P. ; Martin, S.C. ; Boutros, K.S. ; Redwing, J.M.
Author_Institution :
Dept. of Electr. Eng., California Univ., Los Angeles, CA, USA
fDate :
7/1/1999 12:00:00 AM
Abstract :
An Al/sub 0.3/Ga/sub 0.7/N/GaN heterostructure field effect transistor (HFET) grown on semi-insulating SiC with an 0.2-μm gate length is reported. A source-drain ohmic contact resistance of 0.15-/spl Omega/-mm was achieved through the use of high Al content and high n-type doping (1E19 cm/sup -3/) in the AlGaN donor layer and optimized metallization procedures. We obtained a maximum transconductance of 260 mS/mm, a saturated current density of 1.2 A/mm, and a maximum oscillation frequency in excess of 107 GHz in the devices. The results are one of the best achieved up to now, and they will open up the potential for the applications of AlGaN/GaN HFET´s in high-power microwave radar, remote sensing, and communications.
Keywords :
III-V semiconductors; aluminium compounds; contact resistance; current density; gallium compounds; microwave field effect transistors; microwave power transistors; ohmic contacts; power field effect transistors; semiconductor device metallisation; semiconductor doping; wide band gap semiconductors; 0.2 micron; 107 GHz; 260 mS/mm; Al/sub 0.3/Ga/sub 0.7/N-GaN; III-V semiconductors; high-power microwave applications; maximum oscillation frequency; maximum transconductance; n-type doping; optimized metallization procedures; saturated current density; source-drain ohmic contact resistance; undoped channel heterostructure field effect transistor; Aluminum gallium nitride; Contact resistance; Doping; Gallium nitride; HEMTs; MODFETs; Metallization; Ohmic contacts; Silicon carbide; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
