This book, first published in 2007, focuses on the application of defects and impurities in current and emerging semiconductor technologies. The role of defects in the evolution of semiconductor technology is now recognized as one of refined control - in density, properties, spatial location, and perhaps even temporal variation during device operating lifetime. The concept of defect engineering has found numerous applications in the fabrication of semiconductors and devices with improved and/or new properties, and new trends extend defect engineering in structures with nm dimensions. This book shows interaction among researchers pursing effective use of defect incorporation and control at various facets of technology and widely different semiconductor materials systems. Topics include: dopant and defect issues in oxide and nitride semiconductors; defect properties, activation and passivation; defects in nanostructures and organic semiconductors; ion implantation and beam processing; defect characterization; heterojunctions and interfaces; process-induced defects; dopants and defects in group-IV semiconductors and defects in devices.