The effects of mercury and krypton on the glow discharge decomposition of disilane have been studied. It is found that mercury‐sensitized plasma decomposition of disilane yields higher deposition rate hydrogenated amorphous silicon (a‐Si:H) films. At a deposition rate as high as 60 A˚/s no change was observed on the dark and photoconductivities. A similar effect was obtained in krypton‐sensitized plasma decomposition of disilane.