Oxide materials are emerging as potential candidates for a variety of existing and new optoelectronic and microwave applications. Critical to enabling this development is the need to have high-quality materials and to be able to construct viable heterostructures. The existence of improved metal oxide films has enabled a deeper understanding of both the oxides' intrinsic properties and their potential application in real world electronics. Because of their special properties or combinations thereof, oxide films are leading to new classes of devices as well as potentially replacing common semiconductor devices. This book focuses on the materials growth, characterization, processing, and application of oxide films employed as the active elements in devices. A new understanding of basic materials properties is currently being combined with the development of novel heterostructures to lead to whole new classes of devices potentially affecting everything from energy conversion to computer memory. Topics include: applications; new ideas and magnetism; ferroelectrics and related materials; transparent conductors; and film deposition methods.