Optical Dispersion In Annealed Thin Films of S-doped a-Si:H Alloys

S-doped amorphous hydrogenated silicon (a-Si,S:H) thin films were prepared by conventional PECVD method on corning glass substrates. The prepared thin films were subsequently annealed in vacuum (~ 2 × 10 – 6 Torr) in the temperature range from 100 °C to 500 °C. The annealing effects at room temperature were examined by means of optical transmission spectra of the films in the wavelength range 300-1100 nm. Dispersion in optical constants such as transmittance, bandgap and refractive index were observed. Tailoring in optical constants was observed with respect to doping concentrations as well as the annealing temperatures.