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We report an optimized multi-step chemical vapor deposition process for growing MoS2 thin films. This process enables large-area processing, film patterning simply by using shadow masks, and precise control of the final thickness by changing the initial thickness of the first step of MoO3 film deposition. The structural characterization of the MoS2 films is performed with transmission electron microscopy and X-ray diffraction as a function of film thickness. MoS2 film with a thickness of 3 nm possesses a highly crystalline structure with a spacing of 0.62 nm. The crystallinity and orientation of the films are degraded with increased film thickness. Careful analysis by time-of-flight secondary ion mass spectroscopy reveals that a film with a thickness of 9 nm is not completely sulfurized, and unreacted MoO3 is left at the bottom of the film. These fundamental analyses coincide with the thickness dependence of thin-film transistor (TFT) performance. A TFT with the optimal film thickness of 3 nm achieves high performance, namely a carrier mobility of 0.57 cm2 V−1 s−1 and an on/off ratio of ~ 102.

The magnetization loss of MgB2 wire was investigated using numerical calculations based on the finite element method. Various superconducting properties of MgB2 wire such as nonlinearity and the field dependence of the critical current were considered in the numerical formulation. An analysis of magnetization loss was carried out as a function of the external magnetic field for a wide range of operating temperatures. The numerical results were compared with conventional theories and were found to be in relatively good agreement. An alternate approach based on a normalization method using critical current data was also employed as a simple method for predicting magnetization loss. The effectiveness of the simple equation for predicting loss was verified by comparisons of both values for various temperatures.

ZnO and Ce-doped ZnO Nanofibers on (111) Pt/SiO2/Si substrates were produced using an electrospinning technique. The as-prepared composite fibres were subjected to high-temperature calcination to produce inorganic fibers. After calcining at a temperature of 500 o C, the average diameter of the ZnO and Ce-doped ZnO nanofibers were determined to be 170 nm and 225 nm, respectively. The average grain size of the ZnO and Ce-doped ZnO nanofibers were about 50 nm and 57 nm, respectively. The microstructure, chemical bonding state and photoluminescence of the produced ZnO and Ce-doped ZnO nanofibers were investigated. The Cedoped ZnO nanofiber can be assigned to the presence of Ce ions on substitutional sites of Zn ions and the Ce 3+ state from X-ray photoelectron spectra. Compared with PL spectra of ZnO nanofibers, the peak position of the UV emission of the Ce-doped ZnO nanofibers is sharply suppressed while the green emission band is highly enhanced.

Radiofrequency glow discharge optical emission spectrometry(RF-GD-OES) was used to quantitatively analyze the depth of nanometric Cr/Ni multilayers on a silicon substrate. The technique permitted the rapid and accurate depth profiling of multilayers, down to the nanometer range. The analytical parameters were optimized for the RF-GD-OES depth quantitative analysis of Cr/Ni multilayers on a Si substrate. To validate the RF-GD-OES results, a TEM image was obtained in addition to performing the AES and SIMS depth profiling. confirm the validity of the GD-OES data, TEM imagewas obtained and both AES depth profiling, and SIMS depth profiling were preformed. The findings indicate that RF-GD-OES is a promising analytical tool for the accurate and rapid depth profiling of nanometric metal multilayers on semiconducting substrates.

The influence of lithium doping concentration on the crystallization, the surface morphology, and the luminescent properties of Y1.92O3:Eu0.08 ceramic phosphors were investigated. The crystallinity, the surface morphology, and the photoluminescence (PL) of ceramics depended highly on the Li-doping concentrations. The relationship between the crystalline and morphological structures and the luminescent properties was studied, and Li-doping was found to affect not only the enhanced crystallinity but also the luminescent brightness of Y1.92O3:Eu0.08 ceramics. In particular, the incorporation of Li+ ion into the Y2O3 lattice could induce remarkable increase in the PL intensity. The strongest emission intensity was observed with Y1.68Li0.24O3-δ:Eu0.08 ceramics whose brightness was increased by a factor of 6.5 in comparison with that of Y1.92O3:Eu0.08 ceramics.

To investigate the temperature dependence of a synthesized Zr57V36Fe7 non evaporable vacuum getter material, the in-situ temperature x-ray photoelectron spectroscopy (in-situ XPS) were performed in a UHV chamber equipped with a programmable ceramic sample heating system. The surface and bulk composition of Zr, V, and Ti was determined in the as-received state and after in-situ heating from 50℃ to 600℃ at 50℃per step. The peak fitting results for O 1s, C 1s, Zr 3d, V 2p, and Fe 2p high resolution spectra were acquired and the chemical state of the elements were then characterized as a function of heating temperature. In-situ XPS investigations showed that oxide reduction proceeds via the formation of sub-oxides with the simultaneous formation of carbides in the region near the surface. The activation temperature for completion of the Zr57V36Fe7 alloy, which approximates the XPS peaks changed from oxide to metallic state(20 % of the oxide peak), was determined around 480℃. The findings suggest that the in-situ temperature XPS technique is a useful analytical tool for evaluating activation characteristics of NEG materials.