DERIVATIVE SPECTRA OF POLYCRYSTALLINE ZN1-XCDXSE THIN-FILMS

Derivative spectra have been recorded at room temperature to determine the energies at the lowest gap (E(o)) and spin-orbit splitting parame ter Delta(o) for the electron beam deposited polycrystalline Zn1-xCdxS e (0 < x < 1) thin films on glass substrates as a function of composit ion (x). The spectra clearly indicated the well resolved transitions d ue to E(o) and E(o) + Delta(o) gaps. A quadratic relation of E(o) and E(o) + Delta(o) with x is observed, giving respectively the bowing par ameters as 0.46 and 0.52 eV. The variation of ao with x at Gamma point is very small and found to be in the range from 0.38 to 0.43 eV.