Narrow Results

Cobalt thin films deposited by radio frequency sputtering were investigated. Microstructures of the Co films were analyzed by XRD and TEM. The results show that films microstructure varies with the variation of the sputter gas pressure P_Ar. Magnetic properties measured by VSM show that all the films possess relatively high saturation magnetization 4πM_s, and strong in-plane uniaxial magnetic anisotropy field H_k. Co films deposited below 0.3 Pa show soft magnetic properties and its microwave permeability was measured by vector network analyzer in the 0.1–5 GHz range.

Hydrogenated amorphous SiC films (a-Si_1-xC_x:H) were prepared by DC magnetron sputtering technique on p type Si(100) and corning 9075 substrates at low temperature, by using 32 sprigs of silicon carbide (6H-SiC). The deposited film a-Si_1-xC_x:H was realized under a mixture of argon and hydrogen gases. The (a-Si_1-xC_x:H) films have been investigated by scanning electronic microscopy equipped with EDS system (SEM-EDS), X-rays diffraction (XRD), secondary ions mass spectrometry (SIMS), Fourier transform infrared spectroscopy (FTIR), UV-visible-IR spectrophotometry, and photoluminescence (PL). XRD results showed that the deposited film was amorphous with a structure of a-Si_0.81C_0.19:H corresponding to 19 at.% carbon. The photoluminescence response of the samples was observed in the visible range at room temperature with two peaks centered at 463 nm (2.68 eV) and 542 nm (2.29 eV). The structural properties and the origin of the luminescence were discussed.

At room temperature, titanium dioxide (TiO₂) films were deposited by the direct current pulse magnetron sputtering technique. Varying O₂/Ar flow ratio, TiO₂ films with different nanocrystalline structures were obtained. The high resolution transmission electron microscopy results show that with O₂/Ar = 6/14, the nanocrystalline in rutile phase appears in as-deposited film. Then X-ray diffraction patterns of annealed films revealed that with O₂/Ar = 6/14, the higher weight fractions of rutile TiO₂ appear in films. The optical emission spectroscopy results show that with O₂/Ar < 6/14, O element was mainly existed as O^-/O⁺ ions, instead of excited state of O atoms.

During the sputtering-deposition process, the temperature of film growth surface is more important than that of the substrate, which could seriously influence the film growth behavior. While, it is difficult to measure the temperature of film growth surface, because of the low space resolution of traditional temperature measurement systems. In this paper, the temperature of TiO₂ film growth surface and substrate were monitored by the home-made NiCr/NiSi film thermocouple and standard NiCr/NiSi K type wire thermocouple. With the same sputtering parameters, the temperature of TiO₂ film growth surface could reach $846.2\pm 3.9^{\circ }$C. While, the temperature of substrate was only about $305.8\pm 1.4^{\circ }$C. Finally, combining the temperature of film growth surface in sputtering-deposition process, the film growth behavior can be investigated and controlled in future.

Indium tin oxide (ITO) is widely used in the optoelectronic industry as a transparent conductive oxide owing to its excellent optical and electrical properties. To improve the physical properties of ITO, highly conductive ITO/Ag/ITO multilayer electrodes were prepared using radio frequency (RF) magnetron sputtering at room temperature. Then, laser annealing was performed on the multilayer electrodes with scanning intervals of 0.01, 0.02, 0.05 and 0.1 mm. The structural properties of the multilayer electrodes were characterized by X-ray diffraction, and their optical and electrical properties were characterized by ultraviolet (UV) visible spectrophotometry and a four-point probe station, respectively. The results demonstrated that the multilayer films had a polycrystalline structure, and ITO (222) and Ag (111) preferred orientations were identified after laser annealing. In addition, the crystalline size of the Ag layers increased slightly, implying that the defect density within the Ag layers was reduced, resulting in a significant increase in its conductivity. A significantly low electrical resistivity of 5.35 $\mathrm{\Omega }$/sq and high optical transmittance of 85% were achieved. The Haacke index value was ${\varphi }_{\mathrm{\text{Vis}}}\cong 37.74\times 10^{-3}{\mathrm{\Omega }}^{-1}$, which was much better than the value of ${\varphi }_{\mathrm{\text{Vis}}}\cong 18.14\times 10^{-3}{\mathrm{\Omega }}^{-1}$ before laser annealing.

In this paper, Cu thin films were successfully deposited on glass substrates using DC magnetron sputtering at varying deposition times. The deposition time was varied as 5, 9, 11 and 17min. The obtained Cu thin films were analyzed for morphology and topography using atomic force microscopy (AFM). The size of the surface structures/grains was seen to evolve with deposition time. The conventional/statistical, fractal and multifractal analyses were carried out on AFM images using existing imaging algorithms. The arithmetic roughness and interface width parameters were seen to evolve with the sputtering time. The autocorrelation and height–height correlation functions revealed that the surfaces of all the Cu thin films exhibited self-affine character, but were not mounded properties. The fractal dimensions computed using box counting and power spectral density functions revealed that larger dimensions were associated with larger surface features. The lacunarity coefficients were too small indicating that the surfaces were generally deficient in porosity and other defects. The multifractal analyses revealed that spatial roughness does not exhibit linear relationship with the deposition time. The study reveals that surface evolution and nanoscale behavior is significantly influenced by the deposition time although a linear relationship is not established.