摘要 |
A mercury-cadmium-telluride photodiode array detector having a composite structure which includes a p-type HgCdTe substrate, a surface of which is implanted with n-type regions, thereby forming individual photodiodes of the array. Overlying this surface is a layer of insulating dielectric containing a buried layer of guard plate metalization. Overlying the dielectric is a layer of field plate metalization. Openings made through the field plate, dielectric, and guard plate allow for electrical contact with the individual photodiodes. The openings within the guard plate are made larger than those within the field plate. When these two plates are appropriately biased by external voltage sources, the substrate surface underlying the field plate and surrounding each diode is made to invert. The substrate surface underlying the guard plate remains at flat band potential, thereby electrically isolating the inverted surface surrounding each diode from the other inverted surfaces.
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