GaAs power f.e.t.s with electron-beam-defined gates

The fabrication of GaAs power f.e.t.s having 1 ?m electron-beam-defined gates with 4800 ?m total gatewidth is described. The microwave performance at X-band is compared with that of conventionally defined devices having 2 ?m gate lengths.     

Ion implanted GaAs bipolar transistors

GaAs n-p-n bipolar transistors were fabricated by ion implanting Be and Se into bulk n-type substrate material. Devices with mesa collectors exhibit a d.c. current gain hFE ? 8 and a reverse bias leakage current of less than 10 nA.     

Ion-implanted GaAs X-band power f.e.t.s

Active layers for GaAs power f.e.t.s have been produced by Si implantation into Cr-doped substrates followed by a simple proximity-annealing technique. Devices fabricated on these layers have up to 1.05 W/mm gate width at 10 GHz. This performance is equal to that of epitaxial devices.     

Fabrication and High-Temperature Characteristics of Ion-Implanted GaAs Bipolar Transistors and Ring-Oscillators

GaAs bipolar transistors and ring-oscillators were fabricated by ion implantation into VPE structures. The transistor and circuit performance was tested between 25°C and 400°C. Leakage currents determine the useful temperature range. Present GaAs circuits fail at approximately 390°C due to the metallization technology.