Extrinsic infrared detector with dopant site charge- neutralization

摘要

A relatively thin layer of extrinsic material formed on the top surface of a nearly intrinsic semiconductor substrate forms the detector area of an infrared detector device. A source region is provided along a portion of the perimeter of the detector area and is electrically coupled to the extrinsic detector area by means of an external connection. A drain channel is provided which is separated from the detector area by a gate region. The concentration of the extrinsic material in the detector area is sufficient for it to be at least a poor conductor. Thus, replacement electrons can flow from the source region into the extrinsic detector area via the external connection and electrical charge- neutrality can thereby be maintained at the extrinsic sites. The gate electrode forms a fringing field extending into the detector area which facilitates conduction from the detector area to the drain channel during the read-out process. An X-Y addressable array of such detectors can be readily fabricated using silicon MOS technology.