POROUS SILICON - THEORETICAL-STUDIES

Porous silicon has attracted considerable scientific interest ever since the recent discovery of visible photoluminescence. We present a review of the theoretical work done on this material, We describe the classical theories and computer simulations of the growth of this brittle, spongy structure. The electronic structure calculations based on first principles local density approximation as well as semi-empirical methodologies are outlined. Phenomenological models for photoluminescence, its broad lineshape, decay and temperature dependence and excitonic effects on optical behavior are reviewed. Rudimentary theories of electroluminescence, transport and quantum efficiency are also described. A unified, consistent theoretical framework appears to be a distant goal. Broad suggestions for further theoretical work are outlined.