Polycrystalline silicon (commonly called "polysilicon") is the material of choice for photovoltaic (PV) applications. Polysilicon is the purest synthetic material on the market, though its processing through gas purification and decomposition (commonly called "Siemens" process) carries high environmental risk. While many current optoelectronic applications require high purity, PV applications do not and therefore alternate processes and materials are being explored for PV grade silicon. Solar Silicon Processes: Technologies, Challenges, and Opportunities reviews current and potential future processing technologies for PV applications of solar silicon. It describes alternative processes and issues of material purity, cost, and environmental impact. It covers limits of silicon use with respect to high-efficiency solar cells and challenges arising from R&D activities. The book also defines purity requirements and purification processes of metallurgical grade silicon (MG-Si) and examines production of solar grade silicon by novel processes directly from MG-Si and/or by decomposition of silane gas in a fluidized bed reactor (FBR). Furthermore, the book: Analyzes past research and industrial development of low-cost silicon processes in view of understanding future trends in this field. Discusses challenges and probability of success of various solar silicon processes. Covers processes that are more environmentally sensitive. Describes limits of silicon use with respect to high-efficiency solar cells and challenges arising from R&D activities. Defines purity requirements and purification processes of MG-Si. Examines production of solar grade silicon directly from MG-Si.