Space-charge-limited conduction in Si n+–in+ homojunction far-infrared detectors

Abstract
An analytic model is presented to describe the space‐charge‐limited (SCL) conduction in Si homojunction interfacial work‐function internal photoemission far‐infrared detectors. The basic detector unit is a thin n+in+ structure, which is operated at low temperatures and characterized by an interfacial work function at the n+i interface. The unique aspects of this case lead to simple analytic expressions for all variables of interest. The barrier shape and free‐carrier concentration distribution in the i layer, and their dependence on the applied bias, i layer thickness, and compensating acceptor concentration, are calculated. The SCL current–voltage characteristic is also investigated as a function of i layer parameters. The results obtained are useful for the IR detector design and performance optimization.