A study of plasma-deposited amorphous SiOx:H (0⩽x⩽2.0) films using infrared spectroscopy

The Si–O stretching mode in amorphous SiOx:H (a-SiOx:H) films, prepared by rf glow discharge decomposition of a SiH4–O2 mixture at 300°C, has been investigated by infrared absorption measurements as a function of the O content x. It was found that the ratio, IAS1/NSi, of the absorption intensity of the Si–O stretching mode centered around 1000 cm−1 to the density of Si atoms increased linearly with increasing x, up to x=0.6. Above x=0.6, the rate of increase of the IAS1/NSi values became slower. However, the ratio, Isum/NSi, of sum of the absorption intensities for both 1000 and 1150 cm−1 bands to the density of Si atoms increased linearly with increasing x for x>0.6. We obtained the proportionality coefficient, ASiO, of the Si–O stretching mode to be 1.48×1019 cm−2. The characteristic of the Si–O stretching mode and the ASiO are discussed.