The Silicon-based alloys deposited by Enhanced Plasma Chemical Vapor Deposition (PECVD) are of much interest to large area applications and comercial mass production. Germanium is currently the most interesting low-optical gap material that can provide many potential advantages to silicon-based technologies. For example, the hydrogenated silicon-germanium (SiGe:H) alloys are used in multiple-junction devices due to their potentially higher conversion efficiency than only silicon-based devices. The narrow optical gap of these alloys and compatibility with silicon films deposited by plasma are the main advantages. The silicon-germanium alloys with relative low-optical gap (Eg=1.5 eV) for Ge content less than 40% are commonly used in multiple-junction amorphous solar cells, although a lower optical gap (Eg~1.2 eV) for high Ge content (>50%) is highly wishful. Morehover the low optical gap and the high absorption coefficient in the wavelength 1500nm make the germanium-based alloys an interesting material for near infrared applications (micro-bolometers). Another potential advantage with the uses of Ge materials is the higher hole (four times) and electron (two times) mobility rather than Si materials. The versatility of PECVD process allows relative low deposition temperatures Td<300°C in comparison to the thermal deposition techniques. This versatilityis of much interest for the industry and scienties because of the energy reduction of the deposition process, and recently, the compatibility with potential applications in flexible devices on low-cost plastic substrates.