Temperature Dependency of Hall Coefficients in Cadmium Oxide Thin Films Prepared by Thermal Evaporation Technique


In this work, the temperature dependencies of Hall coefficients in cadmium oxide thin films prepared by thermal evaporation technique. These coefficients included temperature-dependent Hall coefficient, logarithmic Hall coefficient and Hall mobility. Results showed that the extrinsic conduction prevails in studied samples and impurity atoms introduce energy levels within the energy gap and act as donors. The activation energy of the impurities generally ranged between 0.020eV and 0.070eV. An increase of carrier mobility with temperature was observed then it decreased in higher temperature due to lattice scattering of charge carriers. The values of optical bandgap ranged between 2.90eV and 3.30eV, which is in a good agreement with the those obtained for bulk CdO:Sn samples.