We evaluate the hydrogen content in hydrogenated amorphous germanium-and carbon- and also boron- and phosphorus-doped nanocrystalline silicon films obtained by a plasma chemical deposition technique. The films were made of a silicon-containing mixture (silane) heavily diluted with hydrogen and an inert gas (argon), and also methane and germane. In the study we use a combination of Infrared spectroscopy, recoil proton method and X-rays diffraction analysis. The hydrogen content is found to be as great as16 at% for the nanocrystalline films and 24 at% for the alloys. The hydrogen content in the alloys increases with the carbon concentration and decreases with germanium. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.