Bandgap and dispersion of the refractive index groups AsxSe1-x


Purpose. The relevance is that the study of amorphous semiconductors today is one of the most active parts of condensed matter. No doubt that effective incentive for basic research is perspective of non-crystalline materials technology.
Methods. Edge optical absorption and dispersion of the refractive index was investigated using a spectrophotometer SF-46, changing the wavelength range from 450 to 1100 nm, 5 nm increments. The method evaporation of small particles of substances that fall continuous and uniformly to the surface of hot evaporator. If simultaneously evaporating large number of small particles, each of which is in various stages of evaporation, then the uniform distribution of points in time to fall on the evaporator provided average chemical composition of steam that corresponds to the composition of the starting material.
Results. In the investigation of absorption edge is established that the studied material Tautsa the relation in which calculated values of energy and constant s, reflecting the degree of increase in the absorption of energy. Experimental results dispersion of the refractive index of the studied materials described by single oscillators Wemple and Borez also parameters of these models.
Conclusion. Investigated optical absorption edge thin-layer structures AsxSe1-x at 0,18<x<0,67. Established, that the absorption edge of the investigated material is consistent with the known law Tautsa. Found that Tautsa slope of curves for the investigated materials decreases with increasing concentrations of arsenic, and in the concentration range х=0,40 and х=0,50 observed features, as on the concentration dependencies , that is related a change in the structure of local materials

Keywords: energy Tautsa, refractive index, optical absorption, the degree of ionicity