Effect Of DC Power Research Articles

The effect of DC power and annealing on the structural, optical, and electrical characteristics of sputtered amorphous WOX thin films

Tungsten oxide (WOX) is considered as one of the promising materials due to its unique properties in widespread optoelectronic and photonic applications. This study reports on the deposition of WOX thin films via reactive magnetron sputtering technique with various low DC power and constant sputtering pressure at room temperature. XRD results reveal that an amorphous state for all the as-deposited films, while annealed films at 650 °C have WO3 monoclinic structure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies indicate all as-deposited films have a dense, homogeneous, and quite smooth surface with a root-mean-square roughness (σRMS) below 1 nm. Annealing significantly affects film morphology, the formation of large grains and increasing the surface roughness. Optical parameters were examined by ultraviolet–visible (UV–Vis) spectrophotometer. Increasing sputtering power leads to a decrease in transparency value, an increase in absorbance, a reduction in penetration depth, a red shift of the fundamental absorption edge, and a reduction in the band gap energy from 3.06 eV to 2.61 eV. The annealed films exhibit a smaller optical band gap compared to as-deposited films in the range of 2.44 eV–2.93 eV. The temperature dependence of the sheet resistance corresponds to the Arrhenius law for as-deposited films with DC power of 10 W–30 W, indicating semiconducting nature. A decreasing trend in activation energy (0.283–0.055 eV) was observed with increasing DC power. All the annealed films exhibit insulator nature with a resistance of more than 100 MΩ. Analysis of these results suggests that the desired structural, optical, and electrical properties can be achieved by controlling deposition conditions.

Effect of DC power on opto-thermal properties of AlN thin films

Effect of DC power on opto-thermal properties of AlN thin films

Growth and characterization of co-sputtered aluminum-gallium oxide thin films on sapphire substrates

Aluminum gallium oxide (AGO) films were deposited on c-plane sapphire by co-sputtering of Al and Ga2O3 targets at a substrate temperature of 600 °C, and then annealed at 900 °C to enhance their crystal quality. The effect of DC power (0, 5, 10, 30, 50 and 70 W) for Al target on the structural, optical and compositional characteristics of AGO films were investigated. After annealing, the films prepared at the DC powers of 0–50 W for Al target all exhibited the single crystalline structure with the (−201) plane family. The annealed film grown at the DC power of 10 W possessed the highest crystal quality than the others. With increasing the DC power from 0 to 70 W, the Al composition of AGO film increased from 0 to 6.08 at.%, while its bandgap increased from 4.89 to 5.19 eV. X-ray photoelectron spectroscopy studies indicate the intensity of Ga 2p3/2 peak (1117.9 eV) for the AGO film decreases, whereas the intensity of Al 2p peak (74.6 eV) increases with increasing the DC power. The metal-semiconductor-metal photodetector with the annealed AGO film deposited at the DC power of 10 W possesses the largest photocurrent of 5.7 × 10−9 A and the on/off current ratio (Ion/Ioff) of 1.5 × 104 (@2 V and 230 nm). The better optoelectronic performance of this device was attributed that the AGO film (DC power: 10 W) had a higher crystal quality, the O/(Al+Ga) ratio close to the optimum value of 1.5. Our results present the AGO films can be successfully prepared via sputtering technique, which are highly potential for deep-ultraviolet applications.

The effects of DC power on the physical properties and surface topography of sputtered TiN nanostructured thin films

Four high quality nanostructured thin films of titanium nitride, with thicknesses equal to 81, 325, 485 and 565 nm respectively, were deposited on glass substrates by the reactive magnetron sputtering method using different DC power values (from 200 to 410 W). The results revealed that the DC power plays a crucial role in the evolution of the thickness, topography, microstructure, optical and semiconducting properties of the resulting thin films. Specifically, an increase in the DC power enhances the crystalline order of the samples, consequently; the energy band gap values and the electrical resistivity decrease. Also, a competitive growth of crystalline planes of different orientations was found as a consequence of the increment of the grain size. In addition, the influence of DC power on the 3-D surface morphology of these thin films was investigated. The largest peak height and also the largest valley depth from the mean surface increased at higher amounts of DC power. The flexible variation of the physical properties of thin films with the simple and reproducible variation of the DC power in the sputtering process could be exploited in the use of these samples in specific technological applications.

Effect of DC Power on the Structural and the Electrical Properties of B-ion-doped ZnO Films

Effect of DC Power on the Structural and the Electrical Properties of B-ion-doped ZnO Films

Effect of DC Power on Structural and Hydrophilic Activity of TiO<sub>2</sub> Films

In this work, we present the effect of DC power from 100 W to 500 W on the structural and hydrophilic activity of TiO2 films. The TiO2 films were prepared by DC magnetron sputtering on the glass substrate without any external heating. The structure of TiO2 films were analyzed by atomic force microscope and X-ray diffraction. XRD patterns indicated the films were amorphous. The surface roughness and grain size were enlarged by the increasing of the DC power while the substrate temperature was climbed up with the increasing of the DC power. From the point of energetic ion bombardment, it was related with DC power between sputtering processes. The hydrophilic activity of TiO2 films were analyzed by the contact angle meter. The water contact angle decrease with increasing of the DC power.

Influence of process parameters on the characteristics of indium zinc oxide thin films deposited by DC magnetron sputtering

The deposition of indium zinc oxide (IZO) thin films was carried out on glass substrate at room temperature by dc magnetron sputtering. The effects of dc power and deposition pressure were investigated with respect to physical and optical properties of films such as deposition rate, electrical properties, microstructure and transmittance. As the dc power increases, the resistivity slightly increases and the transmittance gradually decreases. For the variation of deposition pressure, the resistivity greatly increases and the transmittance is decreased with increasing deposition pressure. The observation of the IZO films by atomic force microscopy indicates that the microstructure and surface morphology of the films are responsible for the transmittance. It was demonstrated that IZO films with a resistivity of 3.8×10 −4 Ω cm and an optical transmission of 80–90% in the visible spectrum could be prepared without post deposition annealing.

Effects of DC power on the properties of DLC coatings on the OPC drum

Diamond-like carbon (DLC) films were deposited on the organic photoconductor (OPC) drum of the laser printer using the dc-remote plasma enhancement chemical vapor deposition (RPECVD) method. Only methane (CH4) was used as a source gas for DLC coating. The transmittance of the DLC coatings is over 90% and the hardness of the DLC film (130 nm thick) coated OPC drum is higher than 1,000 Hv. Effects of dc-power on the physical properties of the DLC film and the electrophotographic properties of the DLC coated OPC drum were investigated. The hardness and the deposition rate of the DLC film deposited on the OPC drum increased but the transmittance and the surface roughness nearly did not change with increasing the dc power of the dc-RPECVD. The residual potential, the acceptance voltage, and the dark decay rate significantly increase but the photodischarge rate decreases with increasing the dc power of the RPECVD. The optimum dc power is 8.6 kW (950 V, 6A). The friction coefficient of the OPC drum is also lowered by DLC coating. In addition, it was found that the DLC deposition rate could be doubled by imposing magnetic fields around the cathode.