Performance and reliability of GaAs based power HFETs

This paper reports on performance and robustness to hot electron effects of GaAs based power HFET's. The performance and the reliability provide a promise of the fabricated device to be a good candidate for practical circuit application. The effective gate length can be controlled by a selective dry etching. In the latter case particular care must be taken to avoid deep surface levels which can originate instabilities of device even if of limited amount. Transconductance frequency dispersion has been employed to analyze these deep levels and can be used to control the fabrication process in order to minimize their concentration.