GaAs semi-insulated-gate FETs (SIGFETs) as high power MMIC control devices

The GaAs SIGFETs device structure, fabrication, initial experimental performance and advantages compared to conventional recessed-gate GaAs MESFET devices are described. GaAs planar SIGFETs have been fabricated with higher continuous-wave power handling capability than and similar switching frequency figure-of-merit to those of comparable GaAs recessed-gate MESFETs. Initial SIGFET devices demonstrated 3 dB to 5 dB increase in power-handling capability with a switching frequency figure-of-merit of 362 GHz. This improved power performance is due chiefly to the semi-insulated layer under the gate metal, which allows higher gate-breakdown voltage as well as higher drain saturation current. >