Pyrolytic transformation from polydihydrosilane to hydrogenated amorphous silicon film

Abstract The fabrication of thin film silicon devices based on solution processes rather than on conventional vacuum processes is of substantial interest since cost reductions may result. Using a solution process, we coated substrates with polydihydrosilane solution and studied the pyrolytic transformation of the material into hydrogenated amorphous silicon (a-Si:H). From thermal gravimetry and differential thermal analysis data a significant reduction in weight of the material and a construction of Si Si bonds are concluded for the pyrolysis temperature T p = 270 to 360 °C. The appearance of amorphous silicon phonon bands in Raman spectra for films prepared at T p ≥ 330 °C suggests the construction of a three-dimensional amorphous silicon network. Films prepared at T p ≥ 360 °C exhibit a hydrogen content near 10 at.% and an optical gap near 1.6 eV similar to device-grade vacuum processed a-Si:H. However, the infrared microstructure factor, the spin density, and the photosensitivity require significant improvements.