Optical and electrical properties of doped Pb_(1-x)(Mg_(1-y)Sr_y)_xS thin films prepared by hot-wall epitaxy

摘要

We have investigated the optical and electrical properties of Bi- or Tl-doped Pb_(1-x)(Mg_(1-y)Sr_y)_xS thin films. The films with carrier concentration sufficient for use as cladding layers in a laser diode, were obtained by doping with Bi as n-type impurity or Tl as p-type impurity. Optical absorption was observed at far-infrared region on the Bi-doped films, and the relation between absorption coefficient a and carrier concentration n was found to be expressed as α = 0.27n~(0.21) at 6 μm.