The phase transition of hydrogenated SiGe (SiGe:H) films in plasma enhanced chemical vapor deposition was investigated by varying Ge content and hydrogen dilution ratio, R; the phase transition was then compared with that of hydrogenated Si (Si:H). The incorporation probability of Ge in SiGe: H films was strongly affected by R and continuously increased when R ranged from 7.5 to 80. The incorporation of Ge might interfere with the formation of crystalline seeds in the film due to the increase of disorder. However, once the crystalline seeds are formed in the SiGe: H films, the crystalline volume fraction increased with R more rapidly than that did for Si: H films. (C) 2013 Elsevier B.V. All rights reserved.