STUDY OF THE OPTICAL CHARACTERISTICS OF EPITAXIAL PbS1-ySey LAYERS
Keywords:
absorption spectra, solid solutions characteristics, nondegenerate semiconductors, dispersion of the index of refraction, low additional absorption.Abstract
For designing new high-performance IR optoelectronic devices based on the strained layers of semiconductors PbS1-ySey, the methods of determination of the optical characteristics of particular compositions at the concentration of currentcarriers≤1018cm-3 were improved. When studying the dispersion of the refractive index in the layers more than 4 μm in thickness, it was found that, under these conditions, the refractive index in a widerband layer was higher than in a narrow-band layer at the concentration of current carriers ~1019 cm-3. The deviation from linearity at long wavelengths associated with plasma absorption. In the long-wave region, the additional absorption in the layers of this typeis revealed at a lower level than in thinner ones and can be explained by the absorption at the layer-substrate interface reduced to the entire thickness or by transitions between different branches of the allowed band in a particular case at a low concentration of current carriers in these layers.
