P-contact MESFETs for high voltage mixed-mode RF-applications

MESFETs with P-well operating at higher drain voltage generate holes by impact ionization. They charge the GaAs substrate, give rise to increased output conductance and drain current transients at low temperature and facilitate inter-device coupling. Draining the holes by a P/sub +/-contact, which is attached to the source as an integral part of the device structure, neutralizes the adverse impact of holes on device performance. The improved MESFET is utilized in the digital section of a single-pole-eight-throw RF switch with integrated decoder.