Effect of Substrate Temperature on the Optical Properties and the Deposition Rate of a-Si:H Films Deposited by Gas-Jet Electron Beam Plasma CVD Method

Abstract

Layers of intrinsic hydrogenated amorphous silicon (a-Si:H) were deposited with high rates (1.5-2 nm/s) by gas jet CVD method with electron beam activation from mixture of silane with argon on glass substrates at temperatures up to 415 C. The optical parameters (the refractive index, the absorption coefficient, and optical band gap) and the thickness were determined from transmission spectrum in the range of 500–900 nm using the PUMA method. The spectral dependence of the refractive index and the absorption coefficient was obtained by varying the substrate temperature. The optical band gap was determined using Tauc method and the estimated values were in range 1.94-1.84 eV for various substrate temperatures. The calculated thicknesses for all samples were about 1 micrometer. The film’s deposition rate as a function of the substrate temperature was found.