This book is the first to give a comprehensive review of the theory, fabrication, characterisation, and device applications of abrupt, shallow, and narrow doping profiles in semiconductors. Such doping profiles are a key element in the development of modern semiconductor technology. After an introductory chapter setting out the basic theoretical and experimental concepts involved, the fabrication of abrupt and narrow doping profiles by several different techniques, including epitaxial growth, is discussed. The techniques for characterising doping distributions are then presented, followed by several chapters devoted to the inherent physical properties of narrow doping profiles. The latter part of the book deals with specific devices. The book will be of great interest to graduate students, researchers and engineers in the fields of semiconductor physics and microelectronic engineering.