Noise in Semiconductors and Photoconductors

A survey is given of theory and experiments on noise in bulk semiconductors and photoconductors. This paper is divided into four parts, including generation-recombination (gr) noise in semiconductors, gr noise in photoconductors, 1/f noise in single crystals, and modulation noise in granular materials. In the first part an account is given of the appropriate analyses and the results are applied to extrinsic as well as intrinsic fluctuations, generated either in the bulk or at the surface. In the part about photoconductors the limiting sensitivity caused by photon noise is calculated and present infrared detectors are discussed. Next, a survey is given about present understanding of 1/f noise, and of its relation to the field effect as proposed by McWhorter and others. Finally, some remarks are made about 1/f noise in granular material and the proposed theories are briefly reviewed.