Title :
Self-aligned 0.25 mu m W/Ti/Au gate process for high-performance pseudomorphic InAlAs/InGaAs HEMT
Author :
Lin, P.S.D. ; Hong, W.P. ; Kim, O.H. ; Bhat, R. ; Gaag, B. VanDer ; Schumacher, H.
Author_Institution :
Bell Core, Red Bank, NJ, USA
fDate :
5/24/1990 12:00:00 AM
Abstract :
A new self-aligned gate process employing combined metallisation techniques has been developed and applied to pseudomorphic InAlAs/InGaAs HEMT structures. An asymmetric V-shaped gate defined by electron-beam lithography using a multi-level composite resist was lifted-off after sequential W sputtering and Ti-Au evaporation. Ohmic metals were directly evaporated on to the waver to be self-aligned with the gate. The 0.25 mu m gate length FET´s showed a transconductance in excess of 1150 and 1350 mS/mm at 300 and 77 K, respectively.
Keywords :
III-V semiconductors; Schottky effect; aluminium compounds; electron beam lithography; gallium arsenide; gold; high electron mobility transistors; indium compounds; metallisation; semiconductor technology; solid-state microwave devices; titanium; tungsten; 0.25 micron; 0.5 to 26 GHz; 1150 mS; 1350 mS; 300 K; 77 K; 80 GHz; HEMT; InAlAs-InGaAs; SHF; Schottky contact; Ti-Au evaporation; W-Ti-Au gate process; asymmetric V-shaped gate; combined metallisation techniques; electron-beam lithography; gate length; high-performance; lift-off process; microwave device; multi-level composite resist; pseudomorphic structures; self-aligned gate process; sequential W sputtering; submicron gate; transconductance;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19900499
