The fifth in this series of conferences was held in Santander, Spain from 6 to 10 September 1993, and was attended by workers from industry and research institutes worldwide. Device yield is a crucial factor for determining the choice of semiconducting material made by manufacturers, and that choice is based upon a knowledge of how defects might affect a particular substrate, epilayer or base material. The DRIP conference series was instigated to address the mapping of these technologically important defects. Topics covered at the meeting included silicon, and compound semiconductor substrates and epilayers. Methods for defect recognition included tunelling microscopy, inelastic light scattering (Raman), elastic light scattering, photoluminescence mapping, defect characterization, optical probe beams, and effects of defects on devices. The meeting focused in particular on the microscopic nature of as-grown defects: their distribution as a function of growth conditions, and their redistribution under subsequent heat treatments. The conference dealt with the increasing number and sophistication of visualization techniques which map physical properties of defects, and which may in future permit better control of defect engineering. Researchers in solid state or device physics, or electrical engineering will find this volume an invaluable, up to date reference on the latest techniques for the identification of defects, developments in their control, implications for device fabrication, and future directions for the analysis and mapping of semiconductors.