ABSTRACT
We have investigated the optical properties of Pb1-x(Ca1-ySry)xS thin films prepared by hot wall epitaxy. The refractive indices of Pb1-x(Ca1-ySry)xS thin films decreased inversely proportional to the energy band gaps of that. It was revealed that Pb1-x(Ca1-ySry)xS thin films for cladding layer is effective to confine the emitted light in the PbS active layer. The high carrier concentration of Pb1-x(Ca1-ySry)xS thin films were obtained with Bi as a n-type and Ag as a p-type dopant. Infrared absorption of Bi-doped Pb1-x(Ca1-ySry)xS thin films was observed on the transmission measurement by FT-IR. The relation between the absorption coefficient α and the carrier concentration n is expressed as follows: α=4.53 X 10−-17 n 1.03 at 10 μ m.
