The book reviews the most relevant concepts of semiconductor materials and processing including condensed matter physics, electronic device theory, and materials science. It describes the development of energy bands from atomic orbitals and the effect of atomic chemistry on the semiconductor. Semiconductor alloys are described including issues of miscibility, ordering, and electronic properties. Defects in semiconductors are described with particular emphasis on point and line defects, their sources and effects. A chapter on amorphous semiconductors is included as well as a chapter on organic materials used in optical and switching devices. The book concludes with chapters on general aspects of thin film nucleation and growth, physical vapor deposition and chemical vapor deposition methods. Examples of the application of the concepts in each chapter to specific problems or situations is included, along with recommended readings and homework problems.