Title :
Heterojunction vertical FETs revisited: potential for 225-GHz large-current operation
Author :
Weinzierl, Steven R. ; Krusius, J.Peter
Author_Institution :
Sch. of Electr. Eng., Cornell Univ., Ithaca, NY, USA
fDate :
5/1/1992 12:00:00 AM
Abstract :
The high-speed operation of submicrometer AlxGa1-x As/GaAs unipolar heterojunction transistors is examined using two-dimensional time-dependent self-consistent ensemble Monte Carlo simulation. Careful device design can significantly increase ballistic injection over the heterojunction in steady state by eliminating retarding gate-induced space-charge reversal there. Design for optimal large-signal transient operation must also avoid gate-voltage-dependent ballistic injection. General design principles for optimizing high-speed operation are proposed. The resulting VFETs show cutoff frequencies of 225 GHz at large drain currents at 300 K, with frequency-independent two-port y parameters
Keywords :
III-V semiconductors; Monte Carlo methods; aluminium compounds; gallium arsenide; semiconductor device models; solid-state microwave devices; 225 GHz; 300 K; AlxGa1-xAs-GaAs; Monte Carlo simulation; ballistic injection; cutoff frequencies; drain currents; heterojunction transistors; high-speed operation; large-current operation; large-signal transient operation; models; semiconductors; submicrometer transistors; Current measurement; Cutoff frequency; Design optimization; Electrodes; FETs; Fingers; Gallium arsenide; Heterojunctions; Monte Carlo methods; Steady-state;
Journal_Title :
Electron Devices, IEEE Transactions on
