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

fYear

1997

fDate

4-6 Aug 1997

Firstpage

399

Lastpage

406

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 f_T of 35.9 GHz and an f_max 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;

fLanguage

English

Publisher

ieee

Conference_Titel

High Speed Semiconductor Devices and Circuits, 1997. Proceedings., 1997 IEEE/Cornell Conference on Advanced Concepts in

Conference_Location

Ithaca, NY

ISSN

1079-4700

Print_ISBN

0-7803-3970-3

Type

conf

DOI

10.1109/CORNEL.1997.649381

Filename

649381