Awareness of the need to reduce CO2 emissions has only added to the mandate for renewable energy. Public awareness of higher energy prices and global warming problems has opened up the market for solar cells, demanding for generation of electricity and energy supply. Efforts are to make renewable sources a fundamental part of sustained development strategy for energy production. Boosted by the international market, the supply-demand surge in solar cells gave an impetus to the rapid development of solar cell manufacturing industries leading to a tight raw material supply of poly-silicon [1]. Experts predict that demand for technology will rise significantly by the year 2010, initiating the reason for silicon ingot scarcity in the world. This focuses on the expansion of silicon production plants through the Siemens process to promote the optimum utilization of resources. Therefore, it is of paramount importance to the process industries for expansion in the field of process controls. This book presents the design and development of process control of CVD reactors by complaint to IEEE standards. This book helps engineers, researchers, and academicians in the field of Instrumentation.