Structure and optical energy gap measurements in As-Te-Cd chalcogenide thin films

The effect of cadmium on the optical absorption coefficient and optical band gap of the As-Te system has been studied in As40Te/sub 60-x/Cd/sub x/ films with x = 3, 6, 9, or 12. The X-ray diffraction profiles show that the deposited films of all compositions are amorphous. From optical transmittance measurements of the films as a function of photon energy the optical absorption coefficient and the optical gap have been calculated. The optical energy gaps decrease and the absorption coefficients increase with increasing amounts of cadmium