The structural, optıcal and electrıcal propertıes of CdO and Ga doped CdO compounds produced by chemıcal spray prolysıs technıque

In this study, CdO semiconductor films belong to II ? VI group binary compounds have been produced by Ultrasonic Spray Pyrolysis (USP) technique at the substrate temperature of 275 ± 5 °C and the effect of Ga doping (at different concentrations %2, %4, %6, %8) on physical properties of CdO semiconductor films has been investigated. The thickness of undoped and Ga doped CdO films have been determined by spectroscopic ellipsometry. The thickness of the produced semiconductor thin films varies between 0.222?0.286 µm. From the x-ray diffraction spectra of produced films, their structures found to be polycrystal and face centered cubic. Referring to x-ray diffraction spectra of undoped and Ga doped CdO thin films; the lattice constant a, the grain size and the dislocation density values have been calculated for each and vary between 4.68248 ? and 4.69052?, between 220.2 ? and 314.9 ? and between 1.00845×10?3 (nm)?2 and 2.06236×10?3 (nm)?2, respectively. By investigating optical properties of undoped and Ga doped CdO semiconductor films, they are found to have direct band gap and also calculated the varition of forbidden energy gap values between 2.50 eV and 2.66 eV. Two probes method and four probes method have been used to determine the resistivity and electrical conductiviy values varying between 0.2800×10?1 ?.cm and 0.7437×10?2 ?.cm and between 0.3571×101(?.cm) ?1 and 1.3617×102 (?.cm) ?1, respectively.