Improved Hold-Off Characteristics of Gallium Arsenide Photoconductive Switches Used in High Power Applications
NEW MEXICO UNIV ALBUQUERQUE DEPT OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE
Pagination or Media Count:
Electron injection and the subsequent formation of a trap filled region leads to premature device failure in an opposed contact, EL2carbon compensated GaAs photoconductive switch, made through the liquid encapsulated Czochralski process. Due to the electrostatic properties associated with a n-semi-insulating junction, the introduction of a n region next to the cathode suppresses electron injection until higher bias. The doping level, length, and the thickness of the high n region are some of the parameters that affect hold-off characteristics. Extending the length of the n region well beyond the cathode does not increase the hold-off voltage but confines current flow to a narrow strip, which may trigger local heating burnout. Suppression of the effects of the EL2 traps at the nSI interface also does not improve the hold-off characteristics. Opposed contact switches, made from intrinsic GaAs have the characteristics of relaxation semiconductors. The injection of minority carrier results in initial recombination and the formation of a large number of recombination regions may contribute to switching delays and jitters.
- Electrical and Electronic Equipment