This textbook combines a thorough theoretical treatment of the basic physics of semiconductors with applications to practical devices by putting special emphasis on the physical principles upon which these devices operate. Topics treated are the detailed band structure of semiconductors, the effect of impurities on electronic states, and semiconductor statistics. Also discussed are lattice dynamical, transport, and surface properties as well as optical, magneto-optical, and electro-optical properties. The applied part of the book treats p-n junctions, bipolar junction transistors, semiconductor lasers and photodevices, after which the subject of heterostructures and superlattices is taken up with coverage of electronic, lattice dynamical, optical, and transport properties. The book concludes with treatments of metal-semiconductor devices such as MOSFETs and devices based on heterostructures. Graduate students and lecturers in semiconductor physics, condensed matter physics, electromagnetic theory, and quantum mechanics will find this a useful textbook and reference work.