Semiconductor surfaces and interfaces play a vital role in modern-day electronic devices. This is especially true as device dimensions shrink. The properties of clean surfaces and chemically processed surfaces can also have a significant impact on the properties of subsequently grown layers. These surfaces and interfaces may exhibit modified structural, electronic and optical properties, so it is important to understand their effects on subsequent growth, processing and device fabrication. Topics in the book include: structure of surfaces; control of surface defects and properties through chemical etching and passivation; modification of surfaces for growth and processing; nucleation on semiconductor surfaces and self-assembly; the effects of surfaces and interfaces on subsequent growth; and the properties of semiconductor/dielectric and semiconductor/ metal interfaces. In situ and ex situ monitoring of these properties, using various electrical and optical techniques are also presented.