We successfully synthesized high quality single crystal Si nanowires using Al catalyst via vapor-liquid-solid (VLS) mechanism, having diameters ranging from 10 to 200 nm with 10∽20 §­ of length. Characterization of physical and chemical properties of Al-catalyzed Si nanowires using transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) analysis showed that single crystal Si nanowires can be grown with Al-catalyst at 540 ¡C and selective etching of Al existing at the tip of nanowire can provide metal-free Si nanowires that are compatible with conventional Si-based IC process. By using plasma doping method, it was confirmed that the doping level can be controlled and the boron was successfully introduced on Si substrate with 3×1022/cm3 of peak doping concentration.

ZnO nanorods were synthesized by a hot-wall type pulsed laser ablation process. At temperatures 500∼800°C, ZnO thin films and wrinkles were synthesized. Above 800°C, vertically aligned ZnO nanorods were grown on the Si and sapphire substrate without any catalysts. The range of diameter was 100∼300nm. When Au catalyst were deposited on the substrate prior to the deposition, the process range of ZnO nanorod become wider and the diameter of ZnO narrower. Especially, ZnO could be grown selectively along the pattern of Au catalyst with the aid of Au-Zn alloy.

Poly Si1−xGex films have been suggested as a promising alternative to the currently employed poly-Si gate electrode for CMOS technology due to lower resistivity, less boron penetration, and less gate depletion effect than those of poly Si gates. We investigated the formation of poly Si1−xGex films grown by UHV CVD using Si2H6 and GeH4 gases, and studied their microstructures as well as their electrical characteristics. The Ge content of the Si1−xGex films increased linearly with the flux of the GeH4 gas up to x=0.3, and saturated above x=0.45. The deposition rate of the poly Si1−xGex films increased linearly with the flux of the GeH4 gas up to x=0.1, above which it is slightly changed. The resistivity of the Si1−xGex films decreased as the Ge content increased, and was about one half of that of poly-Si films at the Ge content of 45%. The C-V measurements of the MOSCAP structures with poly Si1−xGex gates demonstrated that the flat band voltage of the poly Si1−xGex films was lower than that of poly-Si films by 0.2V.

Dislocation-free Si1−xGex epilayers are successfully grown on (100) silicon at 440°C by ultrahigh vacuum electron cyclotron resonance chemical vapor deposition (UHV-ECRCVD). The effects of process parameters on the crystallinity of Si1−xGex epitaxial layers were studied. As the GeH4 flow rate increases and consequently Ge fraction increases above 20%, Si1−xGex epilayers become damaged heavily by ions. When Ge fraction is larger than 20%, process parameters like total pressure need to be adjusted to reduce the ion flux for high quality Sil−xGex. Growth rate of Si1−xGex epitaxial layers increases at 440°C with Ge content in the film. It is presumed that the hydrogen desorption from the surface is the rate-limiting step, however, the enhancement in growth rate is comparatively suppressed and delayed.

The ternary TiAl-Nb (Llo) alloys stabilized at 1000°C for a week were prepared into miniature specimens for compressive deformation tests. The specimens were deformed in uniaxial compression at room temperature as well as various high temperatures. The yield stress and fracture strain were determined with respect to Nb concentration, and as a function of temperature to investigate positive temperature dependence.

Dislocation structures and other deformation structures of the deformed alloys were studied by TEM.

Ternary Ti-Al-V (Llo) alloys containing vanadium up to 10 at.% and aluminum in the range of 50–55 at.% were prepared. Miniature specimens machined from these alloys were deformed in uniaxial compression at room temperature.

The yield stress, and fracture stress and strain were determined with respect to vanadium and aluminum concentration. The deformed alloys were electropolished into thin foils and studied by TEM. In particular, the types of dislocations, stacking faults and twins in the Ti-Al-V alloys were investigated by TEM.

Binary W-Ni alloys of four different compositions were rapidly quenched into thin foils. Microstructures and hardnesses of the as-quenched alloys were studied by TEM and hardness measurements. The results from the microstructural study show that the W grains and particles undergo extensive refinement and that the grain size is much smaller than that obtained in conventional alloys. In addition, the formation of WNi and W2Ni, the low melting temperature intermetallic compounds in the W-Ni system, was readily suppressed by rapid quenching. The hardness increase in rapidly solidified W-Ni alloys appears to have originated from the microstructural refinement.