NUMERICAL-SIMULATION OF THE HYSTERESIS IN THE SIDEGATING EFFECT IN GAAS-MESFETS - THE EFFECT OF SCHOTTKY CONTACTS

Two-dimensional simulation of the sidegating effect in GaAs MESFET's has been performed. The result confirms that Schottky contacts on semi-insulating substrate cause serious high substrate leakage current and drain current reduction in GaAs MESFET's. The competition between the currents or biases of the contacts is found to be the cause of the S-type negative differential conductivity (S-NDC) or hysteresis observed when measuring the sidegating threshold.