Alternate operating mode for long wavelength blocked impurity band detectors

Numerical modeling demonstrates an alternate bias mode for blocked impurity band (BIB) detectors that can reduce growth constraints on the high purity blocking layer. Initiating depletion from the contact on the active layer (the opposite of conventional operation) significantly reduces the large electric field and resultant voltage drop in the blocking layer. Electric field profiles are presented to show that the alternate bias allows for growth of significantly thicker blocking layers. This could be applied to produce modified BIB devices in far-infrared materials (lambda > 40 mu m) where growth issues associated with the blocking layer have prohibited conventional operation. (c) 2005 American Institute of Physics.