Properties of CdSe polycrystalline thin films grown by chemical bath

CdSe polycrystalline thin films were grown onto glass substrates by chemica l bath deposition at 65 degrees C. Structural, optical, and electrical prop erties of samples were characterized. The layers grew in the cubic phase as evidenced by X-ray diffractograms. Using the first derivative of the optic al absorption vs. phonon energy curves, two transitions were found, the fun damental at 1.8 eV and a second one at 2.2 eV, respectively. It is worthwhi le to mention that the second transition has been reported only for the hex agonal CdSe modification. From the dark conductivity vs. 1/KT behavior on t he 100-500 K range, it could be determined an activation energy of 0.3 eV a t higher temperatures (>350 K) and a behavior following the variable range hopping model of Mott was satisfied at lower temperature. Electron dispersi on spectroscopy measurements indicated stoichiometric CdSe material within the 1% error bar. (C) 1999 The Electrochemical Society. S0013-4651(98)09-081-8. All rights re served.