Geisha Semiconductor Reliability Studies. A Portion of Chair-Geisha

摘要

Studies of radiation effects have been made on gate-controlled diodes with several dielectric passivation systems. Primarily, the surface generation current density increases to about the same final level regardless of its initial value. Exceptions are cases of a passivation system of silicon nitride over residual silicon oxide and certain structures with a polyimide overcoating. Results of the gate-controlled diode studies generally transfer to results on large area, two terminal GEISHA targets. At high junction current levels (> 10 (microamp)) the room temperature reverse voltage capability is not seriously reduced even after high dose irradiations (0.00026 a/sq cm, 0.024 coul/sq cm). Phosphorus gettering has been used to reduce bulk generation current effects in GEISHA targets, thus permitting their use at higher operating temperatures. Passivation using nitride films over thin oxides or protection with polyimide can preserve the low surface generation current properties of gettered material. Additional technology has been developed in patterning polyimide films and in making low thermal impedance mounts for the targets. (Author)