Vertical doping profiles for minimum harmonic distortion in GaAs MESFETs

Theoretical device modeling has shown that distortion in GaAs MESFETs can be reduced by using vertical retrograde doping profiles or an impulse doping profile in the device conducting channel beneath the gate. In this paper we report on fabricating and characterizing devices on GaAs substrates whose active layers have such profiles. It is shown experimentally that the transconductance-gate voltage relationship associated with an impulse doping profile is optimally linear compared with those associated with either uniform or retrograde profiles.