Patent ID: 6211560
Filing Date: 2001-04-03
Classification: H01L

Abstract:
A Schottky barrier infrared photovoltaic detector which outputs a detection signal which is adjusted by an externally applied voltage and which comprises:a silicon substrate having a first and second surface;a silicide layer placed on the first surface of the silicon substrate to form a detector which has a barrier height and which operates in an infrared portion of an electromagnetic spectrum by internal photoemission of holes over an electrical barrier, said detector outputting said detection signal in response to said internal photoemission;a guard ring implanted in said silicon substrate, said guard ring surrounding the periphery of said silicide layer to block surface currents formed on said substrate and to eliminate edge effects;a SiGe intermediate layer which is grown on the said first surface of the said silicon substrate before the growth of the silicide layer, said SiGe intermediate layer producing an interface with a valence band offset that serves as additional barrier to photoemitted carriers; wherein said SiGe intermediate layer has a thickness that is selected from a range of 10 to 800 angstroms; and first and second contact means for making ohmic contact with said silicide layer and with said silicon substrate respectively, said first and second contact means conducting said externally applied voltage to said detector and outputting said detection signal.