This book looks at the exchange of information on the physics and application of amorphous and microcrystalline silicon and presents exciting new developments. Significant progress has been made in the high- or even ultra-high-rate deposition of device-quality amorphous and microcrystalline silicon, in in-situ growth characterization techniques and in state-of-the-art computer modeling of deposition processes. These issues are especially important for the successful future commercialization of silicon thin-film devices. The latest results concerning silicon thin-film solar cells are highlighted. Active matrix arrays for displays or sensors continue to be the second major application of thin silicon films, and again much progress has been made in that area. Topics include: nucleation and growth; novel concepts; hot-wire CVD; high-rate deposition; growth of silicon and silicon-alloy thin films; crystallization; silicon-based alloys; structural properties of heterogeneous silicon films; dopants and impurities; amorphous and silicon solar cells; metastability; hydrogen and metastability; transport in µc-Si; thin-film transistors; hydrogenation and oxidation; defects and defect spectroscopy; structural and electronic properties of thin silicon films; heterojunctions; TFTs and sensors; amorphous-to-microcrystalline transition and structural relaxation and diffusion.