Characterization of transparent conducting CdO films deposited by spray pyrolysis

Abstract

Transparent conducting cadmium oxide (CdO) films have been deposited by spray pyrolysis. The film thicknesses have been determined using Rutherford backscattering spectrometry. X-ray diffraction measurements show that the films are polycrystalline with a preferential orientation along the (1 11) diffraction plane and the lattice parameter has been calculated. The dislocation density and strain have also been evaluated. The films possess a transmittance of about 75% in the visible and near-infrared region. The refractive index is found to vary between 1.68 and 2.84 in the wavelength range 500-1500 nm. The values of indirect and direct bandgaps obtained are 1.98 and 2.32 eV respectively. Hall effect measurements have been carried out in the temperature range 304-349 K. Resistivity, carrier concentration and mobility of the films at room temperature have been evaluated as 6.6 x m2 V-' s-' respectively. Thermoelectric power values from thermoelectric power measurements carried out in the temperature range 304-376 K have been found to be about 19.7-89 I.CV K-'. Laser damage studies performed at a wavelength of 1.06 p m indicate that the films possess a damage threshold density of about 2.37 x lo4 J m-2. Q m, 1.4 x loz5 m-3 and 0.68 x

On the possibility of ferromagnetism in CdO:Mn at room temperature

“…Bulk CdO is an n-type semiconductor with a direct band gap of 2.5 eV and an indirect band gap of 1.98 eV [1,2], even though reports of 2.32 and 1.36 eV are also available [2,3]. CdO thin films exhibit large third-order nonlinear optical properties [4].…”

Annealing Effects on the Interband Transition and Optical Constants of Cobalt Doped Cadmium Oxide Thin Films

“…The dependence of the real (ε 1 ) and imaginary (ε 2 ) parts of the dielectric constant on photon energy are shown in Figs. (9,10). From these figures it can notice that the real and imaginary parts of dielectric constants increase with increasing annealing temperature, and it can show the peaks in the wavelength at 550 nm for all prepared thin films.…”

“…This will,however, degrade the transparency due to increased free carrier absorption [7] , Among these transparent conducting oxides, cadmium oxide (CdO) has received a considerable attention for solar cell application due to its low electrical resistivity and high transparency in the visible range of solar spectrum [8] . Cadmium oxide thin films prepared by various techniques, spray pyrolysis [9][10][11] , ion beam sputtering [11] , chemical bath deposition [12] , activated reactive evaporation [13] , thermal oxidation [14] , reactive sputtering [15][16] and sol-gel [17] . The aim of this study is to study the effect of annealing temperature on the interband transition and optical constants of CdO thin film that doped by 1% Co, utilizing chemical spray pyrolysis technique.…”

Synthesis and characterization of nano ZnO and CdO

“…Due to its large linear refractive index (n 0 = 2.49), it is a promising material for opto-electronic applications and other applications, including solar cells, phototransistors, photodiodes, transparent electrodes and gas sensors. 16) Reduction in the dimensionality of such materials from the three Dimensional (3D) bulk phase to the zero Dimensional (0D) nanoparticles can lead to enhanced non linearity, determined by the quantum size effects and other mesoscopic effects. We report the results of CdO prepared using aqueous chemical method in the following session.…”