Trapezoidal-groove Schottky-gate vertical channel GaAs FET (GaAs static induction transistor)

This paper reports the development of a novel vertical channel GaAs FET with the unsaturated I-V characteristics of the Static Induction Transistor and voltage blocking capability up to 100 volts. The device structure utilizes the anisotropic etching properties of GaAs, in which the gate regions are formed by a double-angle metal evaporation into trapezoidal etched grooves. This single evaporation step simultaneously provides both source and gate metallization, and the novel trapezoidal groove geometry automatically yields a self-aligned gate with separation of source and gate onto different levels, eliminating the need for critical alignment arising from source-gate interdigitation.