Coverage and adsorption state of hydrogen atoms on the growing surface of Si1-yCy film using monomethylsilane has been investigated by using temperature-programmed desorption (TPD) and multiple-internal-reflection Fourier-transform infrared spectroscopy (MIR-FT-IR). The surface hydrogen coverage decreases with the growth temperature T-g until it disappears at 800 degrees C. All the H-2-TPD spectra are well resolved into six SiH-related and one CHn-related hydrogen desorption peaks. The SiH-related FT-IR peak showed a blue shift with increasing T-g, which, in conjunction with the TPD, is related to enhanced C incorporation at backbonds of SiH. (c) 2005 Elsevier B.V. All rights reserved.