Recently there have been major achievements in the study of semiconductor interfaces and microstructures for different materials and structural systems. Progress has been made through various experimental technologies and theoretical methods. This book provides an up-to-date review on these advances and includes the following major subjects: IV-IV, III-V and II-VI semiconductors and metal/semiconductor structures; new developments in growth methods; electric, optical, magnetic and structural characterization and properties; relative theories — electronic transport, phonos and interface modes; devices and applications. These materials are organized into four sections: General, III-V, II-VI and IV-IV, which offer comprehensive information and help readers in following the new developments in the research frontiers of the above fields.