Title :
High microwave and ultra-low noise performance of fully ion-implanted GaAs MESFETs with Au/WSiN T-shaped gate
Author :
Onodera, Kiyomitsu ; Nishimura, Kazumi ; Asai, Kazuyoshi ; Sugitani, Suehiro
Author_Institution :
NTT Radio Commun. Syst. Lab., Kanagawa, Japan
fDate :
1/1/1993 12:00:00 AM
Abstract :
Fully ion-implanted n+ self-aligned GaAs MESFETs with high microwave and ultra-low-noise performance have been fabricated. T-shaped gate structures composed of Au/WSiN are employed to reduce gate resistance effectively. A very thin and high-quality channel with high carrier concentration can be formed by adopting the optimum annealing temperature for the channel, and the channel surface suffers almost no damage by using ECR plasma RIE for gate formation. GaAs MESFETs with a gate length as short as 0.35 μm demonstrated a maximum oscillation frequency of 76 GHz. At an operating frequency of 18 GHz, a minimum noise figure of 0.81 dB with an associated gain of 7.7 dB is obtained. A Kf factor of 1.4 estimated by Fukui´s noise figure equation, which is comparable to those of AlGaAs/GaAs HEMTs with the same geometry, reveals that the quality of the channel is very high
Keywords :
III-V semiconductors; Schottky gate field effect transistors; electric noise measurement; gallium arsenide; gold; microwave measurement; semiconductor device noise; solid-state microwave devices; sputter etching; tungsten compounds; 0.5 micron; 0.81 dB; 18 GHz; 7.7 dB; Au-WSiN-GaAs; ECR plasma RIE; Fukui´s noise figure equation; MESFETs; T-shaped gate structures; carrier concentration; channel quality; channel surface; gate formation; gate length; gate resistance; maximum oscillation frequency; microwave performance; optimum annealing temperature; ultra-low noise performance; Annealing; Equations; Frequency; Gain; Gallium arsenide; Gold; MESFETs; Noise figure; Plasma temperature; Surface resistance;
Journal_Title :
Electron Devices, IEEE Transactions on
