DYNAMIC IV CHARACTERISTICS OF AN ALGAAS/GAAS-BASED OPTOTHYRISTOR FOR PULSED POWER-SWITCHING APPLICATIONS

A high-performance MBE-grown AlGaAs/GaAs-based heterostructure optothyristor has been fabricated and characterized for high-power pulsed switching applications. An LEC undoped semi-insulating GaAs of 650-mu-m in thickness was used as the voltage blocking layer and low-temperature GaAs grown at 200-degrees-C was used to passivate the surface and to reduce the surface leakage current. The dynamic current-voltage characteristics have been measured up to 115 A and 1974 V, which corresponds to a field intensity of more than 30 kV/cm. The dissipated energy per switching as a function of device voltage has also been determined to be in the range of 2 mJ or lower.