Defect calculations in semiconductors Theoretical principles as illustrated by current calculations

Abstract

Experimental studies of semiconductor defects have revealed a range of striking phenomena, both spectroscopic and in the form of defect processes. These results, combined with technological demands for device components, have led to changes in the emphasis and nature of defect theory. The theory of the microscopic processes underlying these phenomena, and the types of calculation which will be needed to elucidate them, are discussed. The status of current calculations and the issues raised by them are described for semiconductor defects ranging from the well-known shallow defects to the qualitatively different deep defects, including vacancy and interstitial centres. Defect processes, both thermally and recombination-induced, are identified and characterized, thereby revealing a wealth of phenomena for which quantitative explanations are necessary.