ANGULAR-DISTRIBUTION OF INTENSITY OF REFLECTED RADIATION INVESTIGATIONS OF THE INFLUENCE OF CO2-LASER TREATMENT ON OPTICAL-PROPERTIES OF HYDROGENATED AMORPHOUS-SILICON

Thin films of hydrogenated amorphous silicon (a-Si:H) were annealed us ing CO2 laser radiation (lambda = 10.6 mu m). Changes of optical prope rties of the treated a-Si:H were investigated using optical transmitta nce spectroscopy and the angular distribution of intensity of reflecte d radiation (ADIRR). The CO2 laser annealing influences the spectral c haracteristics of the real part of refractive index n and absorption c oefficient alpha of light in a-Si:H. This treatment increases the n an d alpha values as well as the Urbach energy of a-Si:H. Simultaneously it decreases the optical energy gap of this material. The changes of o ptical parameters at the interfaces of a-Si:H-glass substrate and a-Si :H-air were established. (C) 1998 Elsevier Science Ltd. All rights res erved.