Properties Of Cadmium Oxide Films Research Articles

Laser induced plasma of cadmium oxide: structural, morphological and optical properties

In this study, the effect of grafting with Iron (Fe) ratios (0.1, 0.3 and 0.5) on the structural and optical properties of cadmium oxide films (CdO) was studied, as these films were prepared on glass bases using the method of pulse laser deposition (PLD). The crystallization nature of the prepared films was examined by X-ray diffraction technique (XRD), which showed that the synthesis of the prepared films is polycrystalline, and Atomic Force Microscope (AFM) images also showed that the increased vaccination with Iron led to an increase in the crustal size ratio and a decrease in surface roughness, The absorption coefficient was calculated and the optical energy gap for the prepared thin films. It was found the absorption decreases and the energy gap decreases with the increase of doping ratio.

Synthesis and Characterization of (CdO)_1-x Mg_x films by pulsed laser deposition

In this study, the effect of grafting with magnesium (Mg) ratios (0.1, 0.3, 0.5) on the structural and optical properties of cadmium oxide films (CdO) was studied, as these films were prepared on glass bases using the method of pulse laser deposition (PLD). The crystallization nature of the prepared membranes was examined by X-ray diffraction technique (XRD), which showed that the synthesis of the prepared membranes is polycrystalline, and (AFM) images also showed that the increased deformation with magnesium led to an increase in the grain size ratio and a decrease in surface roughness, as well as the absorption coefficient was calculated. And the optical energy gap for the prepared membranes, where it was found that the absorption coefficient increases with the increase in the proportion of vaccination and that the energy gap decreases with increasing rates of vaccination.

Impact of zinc doping on structural, optical, and electrical properties of CdO films prepared by sol–gel screen printing mechanism

The simple, economical, eco-friendly sol–gel screen printing mechanism is used to incorporate pure and different zinc- (2, 4, 6, 8%) doped cadmium oxide films on glass substrate at 500 °C calcination temperature. X-ray diffraction (XRD) pattern of prepared films supports the polycrystalline and cubical nature of prepared films. High intensity peak is available at (111) plane for all prepared films. The average crystallite size and strain have been calculated by Williamson–Hall method for all films. The scanning electron microscope (SEM) confirms the impact of zinc on structural morphology of cadmium oxide films. Cd, Zn, O, and absence of any kind of impurities in prepared films has been confirmed by EDAX. It also supports the decrease in atomic percentage of Cd and O with an increase in zinc doping. UV–visible spectroscopy (300–900 nm) of prepared films confirms that the transmittance of films increases up to 60% with 6% doping of zinc and with 8% doping of zinc it decreases. It is also observed that the bandgap first increases up to 2.62 eV on varying doping of zinc from 0 to 6% and then decreases with 8% doping of zinc which clearly shows that the optical properties of cadmium oxide films enhances with doping of zinc. Photoluminescence spectrum of films confirms that there is an enhancement in luminescence property with zinc doping. Fourier transform infrared spectroscopy (FTIR) confirms the presence of Cd–O and O–C–O vibrations in films. Two-probe method has been used for the study of electrical properties of prepared films and it is seen that the electrical resistivity decreases with increase in doping of zinc up to 6% and with 8% doping of zinc it increases.

Influence of solution molarity on structure, surface morphology, non-linear optical and electric properties of CdO thin films prepared by spray pyrolysis technique

The polycrystalline Cadmium Oxide (CdO) thin films were grown on glass slides at 693 K by spray pyrolysis technique. A comprehensive study was carried out to understand the influence of precursor concentrations on structure, surface morphology, optical and electrical properties of the deposited films. X-ray diffraction study shown the cubic phase of the deposits preferentially oriented along (2 0 0) plane. The crystallite size gradually increased with increasing solution molaritiy. The structural parameters have shown systematic variation. SEM images showed the change of spheroid shaped crystallites to flower like structure with increasing molarity. The elemental analysis was examined by x-ray photoelectron spectroscopy. The transmittance is reduced and the absorption edge is red shifted with increasing molarity. Photoluminescence spectra display the origin of CdO near band edge emissions (NBE) in addition to green-yellow emission. The third-order nonlinear optical (NLO) properties of CdO films were measured with (CW) DPSS laser at 532 nm. All the samples have exhibited good optical absorptive effects with reverse saturable absorption (RSA) behaviors. The films have shown n-type electrical conductivity that has increased with molarity due to the enhancement of charge carriers in the deposits.

Influences of indium doping and annealing on microstructure and optical properties of cadmium oxide thin films

The influences of indium doping and subsequent annealing in nitrogen and air atmospheres on the microstructure and optical properties of cadmium oxide films were studied in detail with the aid of various characterizations. X-ray photoelectronic spectroscopy analysis shows that indium atom forms chemically oxidized bonds in Cd–O matrix. X-ray diffraction results demonstrate that CdO structure remains FCC structure with indium doping, whereas the preferential orientation transforms from (222) into (200) orientation. Indium doping prevents the large crystalline growth, and this role still works under both nitrogen and air annealing processes. Similarly, CdO films show rough surface under annealing conditions, but the force has been greatly weakened at high doping level. It is clear that refractive index and extinction coefficient are closely correlated with crystalline size for undoped films, whereas it turns to the doping level for doped films, which can be performed by the mechanism of indium atom substitution. This work provides a very useful guild for design and application of optical–electronic devices.

Effect of thermal annealing on structural, optical and electrical properties of RF reactive magnetron sputtered CdO thin films

Recently, there has been a lot of interest on transparent conducting oxide (TCO) materials which have common application in solar cells and some optoelectronic devices. In this work, cadmium oxide (CdO) thin films have been deposited on glass substrates by RF reactive magnetron sputtering technique and subsequently annealed in air from 200 °C to 500 °C. The effect of annealing temperature on the structural, morphological, optical and electrical properties of CdO films is systematically investigated by X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, atomic force microscopy, UV-visible spectrophotometer and Hall effect measurements. X-ray diffraction (XRD) studies showed that the films are polycrystalline in nature with a preferential orientation along (2 0 0) plane. Atomic force microscopy studies showed that these films are very smooth with maximum root mean square roughness of 3.13 nm. The CdO films formed at annealing temperature of 400 °C exhibited optical transmittance of 84%, electrical resistivity of 1.9 × 10 −3 Ω cm and figure of merit of 1.8 × 10 −3 Ω −1 .

Influence of manganese concentration and annealing temperatures on the physical properties of CdO films grown by the SILAR method

Undoped and doped Cadmium oxide (CdO) films with different Mn concentrations were prepared on glass substrates by the successive ionic layer adsorption and reaction method and annealed at two different temperatures. Structural, morphological and optical conditions were performed by XRD, scanning electron microscope (SEM) and UV–vis spectrum measurements. The deposited films were dense and they adhere well to the glass substrates. From the SEM photographs, it was seen that Mn doping concentration and annealing process affect the morphologies of the nanostructures. It was found that the growth process modifies the microstructures of the CdO films. XRD results and UV–vis analysis reveal that the crystal structure and optical band gap of the films could be adjusted by varying the Mn concentration and annealing temperature. The results also indicate that there is a direct dependence of the physical and optical properties of the metal oxide films on doping concentration and annealing process.

STRUCTURAL AND PHYSICAL PROPERTIES CDO FILMS , OBTAINED BY REACTIVE MAGNETRON SPUTTERING

Structural, electrical and optical properties of cadmium oxide films obtained by means of magnetron sputtering in argon and oxygen mixture at various technological depositional conditions have been investigated. There have been shown opportunity for control by changing of depositional conditions and isothermal annealing. This method have allowed to receive high — conductivity transparent CdO films with specific resistivity of ρ = 3 • 10—4 Ω • cm and optical transparency T ≈ 80 — 90 %.

Electrochemical capacitive properties of cadmium oxide films

The specific capacitances (SC) of cadmium oxide (CdO) films synthesized electrochemically followed by air annealing at 673 K for 2 h onto tin-doped indium oxide (ITO) substrates, in different electrolytes, are estimated using cyclic voltammetry (CV) and galvanostatic discharge experiments and characterized for the structural and surface morphological studies using X-ray diffraction and scanning electron microscopy techniques, respectively. The flake-like surface morphology of CdO film has showed superior SC in KOH electrolyte than that of KNO 3, Na 2SO 4 and NaOH, respectively. Effect of air annealing on shape and enclosed area of CV curves is also studied. Over 1000 cycles, the film electrode was considerably stable, confirming the potentiality of CdO as a capacitive material.

Bias voltage dependence properties of cadmium oxide films deposited by d.c. reactive magnetron sputtering

Cadmium oxide films were grown on glass substrates using d.c. reactive magnetron sputtering technique by sputtering from a metallic cadmium target in an oxygen partial pressure of 1×10−3 mbar under various substrate bias voltages. The substrate bias voltage significantly influences the crystallographic structure of the deposited films. The influence of substrate bias voltage on the electrical and optical properties of the films was systematically studied. The films formed at a substrate temperature of 473 K and bias voltage of −80 V showed an electrical resistivity of 1×10−3 Ω cm, optical transmittance of 86%, optical band gap of 2.47 eV and a figure of merit of 7×10−3 Ω−1.

Deposition and properties of cadmium oxide films by activated reactive evaporation

Activated reactive evaporation (ARE) is a useful technique for the deposition of compound semiconductor films at low temperatures. High quality transparent and conducting oxides and hard coatings of transition metal compounds have been successfully deposited using this technique. However, owing largely to the complexity introduced by plasma, the microscopic deposition mechanism of the process is not yet fully understood. Based upon experimental data of cadmium oxide films deposited by ARE, it is proposed in this paper that the reaction forming CdO is heterogenous. It is also found that the microscopic deposition process and thereby the structural and electrical properties of CdO films are primarily influenced by the chamber pressure and the substrate temperature. The oxygen percentage in the chamber is found to have comparatively less influence on film properties. The data demonstrate that film resistivities as low as 2 × 104Ω cm with about 85% transparency can be obtained using this techinique.

Structural, optical, and electrical properties of cadmium oxide films deposited by spray pyrolysis

Transparent conducting cadmium oxide films are prepared by the spray pyrolytic technique. The dependence of structural, optical, and electrical properties on the film thickness is investigated. X-ray diffraction studies confirm the polycrystallinity of the films and the films show preferential orientation along the (200) plane. The crystallite size and the dislocation density are also determined from the above patterns. The films show about 70% transmittance in the wavelength range 750 to 850 nm and the values of band gap and refractive index are in the order 2.35 to 2.50 eV and 1.95 to 2.65, respectively. Hall measurements indicate that the films are n-type, having carrier concentration ≈ 1026 m−3 and mobility (17.5 to 19) × 10−4m2/Vs.

Structural and electrical properties of cadmium oxide films deposited by the activated reactive evaporation technique

Abstract Transparent and conducting films of cadmium oxide were deposited on glass substrates by the activated reactive evaporation (ARE) technique for the first time. The sublimating nature of cadmium coupled with the reduction in ambient pressure due to oxygen consumption during deposition causes loss of control, which can be mitigated by introducing oxygen to maintain the pressure. The effect of boat temperature and substrate temperature on the structural and electrical properties of the films is reported. These properties are found to be strongly dependent on substrate temperature whereas the boat temperature has little influence. Films are polycrystalline even when substrate temperature is as low as 30°C. As the substrate temperature increases, the films exhibit increasing preferred orientation in (100) direction and a reduction in lattice strain. Simultaneously, the mobility and carrier concentration also improve. The ARE process enables deposition of excellent transparent and conducting films with conductivity about 2500 Ω -1 cm -1 which is as good as the best reported for CdO films.