Narrow Results

A series of undoped and p-doped a-SiC:H samples have been made in the framework of a research plan for obtaining high quality p-type window layers by "Plasma Enhanced Chemical Vapor Deposition (PECVD)" technique from the mixtures of silane (SiH₄), methane (CH₄) and diborane (B₂H₆) gases. For the optimization of the window layer, the dependence of the electrical (conductivity) and optical (band gap) properties due to altered ratios of methane and diborane gases were investigated. When the diborane gas ratio was changed from Y = 0.06 to Y = 0.24 with an increase of 0.06 steps at a constant of X = 0.948 methane gas ratio, the dark conductivity and optical band gap values changed from ~ 10^-19 (Ω·cm)^-1 to ~ 10^-10 (Ω·cm)^-1 and 2.542 eV to 2.178 eV, respectively, and between these values, the most appropriate layers can be selected.

Soft Co films deposited by a method which we called the "weak magnetron radio frequency (RF) sputtering" have amorphous structures. The amorphous structure varies with the increasing of P_Ar. Static magnetic measurements show that all the films possess high saturation magnetization and a well-defined in-plane uniaxial anisotropy with the easy axis parallel with the applied field. The highest coercivity in the easy axis H_ce and in the hard axis H_ch is only 20 Oe and 9 Oe, respectively. The sputter pressure P_Ar affects essentially the uniaxial anisotropy energy K_u. The GHz permeability of the as-deposited films was measured in the 0.1–5 GHz using the shorted microstrip transmission-line perturbation method. The full-width at half-maximum (FWHM) for the peak in the imaginary part of the permeability at resonance is about 1.3 GHz which is far broader than other FWHM reported.

CoFeB nanotubes were fabricated by electroless plating in magnetic field using anodized aluminum oxide template, and the structural and magnetic properties of CoFeB nanotubes were investigated. It is found that some nano-scale particles form on the wall of nanotubes. Both coercivity ratio and squareness ratio of out-of-plane to in-plane are significantly changed by the applied magnetic field during electroless plating, which indicates that directional ordering in amorphous CoFeB nanotubes are achieved during electroless plating under magnetic field. The results show that the applied field impacts the magnetic anisotropy of amorphous nanotubes. The anisotropy is stronger with the magnitude of applied field increasing.

Corrosion resistance of nanocrystalline Fe_73.5Si_13.5B₉Nb₃Cu₁ alloy was investigated and compared to its amorphous counterpart. Low-temperature crystallization occurred during the annealing of amorphous tapes was used to obtain a nanocrystalline structure. The influence of annealing condition on the structure and corrosion resistance of the alloy in NaCl and H₂SO₄ solutions was investigated. Based on the testing results, it was found that nanocrystalline tapes have higher corrosion resistance than amorphous counterpart and H₂SO₄ can promote the occurrence of corrosion compared with NaCl.