Determination of the hydrogen content of a-Si films by infrared spectroscopy and 25 MeV α-particle elastic scattering

The simultaneous hydrogen and silicon atom densities in amorphous silicon, a-Si, films prepared by the glow discharge technique have been measured by 25 MeV alpha -particle elastic scattering. Integrated band intensities for the silicon-hydrogen stretching modes, omega 1s and omega 2s, in the region 1800 to 2200 cm-1 were determined for the same freely supported films. A similar analysis has been carried out for the bands observed at 890, 840 and 640 cm-1. Effective oscillator strengths for the omega 1s and omega 2s modes in a-Si films have been estimated and compared with the current theories on the effect of the silicon matrix on the infrared absorption characteristics.