Title :
High speed high power AlGaN/GaN heterostructure field effect transistors with improved ohmic contacts
Author :
Chu, Keeneth K. ; Murphy, Michael J. ; Burm, Jinwook ; Schaff, William J. ; Eastman, Lester F. ; Botchkarev, Andrei ; Tang, Haipeng ; Morkoç, Hadis
Author_Institution :
Sch. of Electr. Eng., Cornell Univ., Ithaca, NY, USA
Abstract :
Ti/Al/Ti/Au ohmic contacts with low contact resistance (as low as 0.24 Ω mm) were used in fabricating short gate length modulation-doped field effect transistors on MBE-grown AlGaN/GaN layers. Maximum drain current achieved was above 1 A/mm with a transconductance of 182 mS/mm. RF measurements showed a maximum fT of 35.9 GHz and an fmax of 57.0 GHz, both achieved with 0.15 μm gates. Simple analysis showed an electron saturation velocity of 1.3×10 7 cm/s in our device structure. Gate-drain breakdown voltages for these devices were measured to be 30 to 35 V
Keywords :
III-V semiconductors; aluminium; aluminium compounds; contact resistance; electric breakdown; gallium arsenide; gallium compounds; gold; microwave field effect transistors; microwave power transistors; ohmic contacts; power HEMT; power field effect transistors; semiconductor device metallisation; titanium; 0.15 micron; 182 mS/mm; 30 to 35 V; 35.9 GHz; 57 GHz; AlGaN-GaN; MBE-grown AlGaN/GaN layers; Ti-Al-Ti-Au; Ti/Al/Ti/Au contacts; gate-drain breakdown voltages; heterostructure FET; heterostructure field effect transistors; high power FETs; high speed FETs; low contact resistance; modulation-doped FET; ohmic contacts; short gate length MODFET; Aluminum compounds;
Conference_Titel :
High Speed Semiconductor Devices and Circuits, 1997. Proceedings., 1997 IEEE/Cornell Conference on Advanced Concepts in
Conference_Location :
Ithaca, NY
Print_ISBN :
0-7803-3970-3
DOI :
10.1109/CORNEL.1997.649381
