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Silicon films of thicknesses (100 - 800 nm) are deposited on Si[111] substrate at 490°C using Si+ ions of energies (20 - 70 eV) from Silane plasma. The structure of the films depends on the energy of Si+ ions and the film grows epitaxially for ion energy <20 eV. Si films are analyzed by X-ray diffraction technique.

Mechanism and growth rate of Metal-Induced-Lateral-Crystallization (MILC) with annealing temperature range from 550°C to 625°C were studied. Base on the MILC growth mechanism and effect of metal diffusion, a modeling on metal impurity distribution was developed. The modeling can be used to predict the distribution of metal impurity formed in the polysilicon layer after MILC annealing process. By applying the modeling, effects of annealing on the metal impurity distribution can be analyzed.

A comprehensive theoretical analysis is presented of the failure of metallic thin films due to electromigration-induced morphological evolution of transgranular voids. Fully self-consistent dynamical simulations emphasize the important effects on void dynamics of the surface diffusivity anisotropy, together with the strength of the applied electric field and the void size. The simulation results are discussed in the context of an approximate linear stability theory. Our simulations predict formation of wedge-shaped voids, as well as failure due to propagation of slit-like features emanating from void surfaces, in excellent agreement with recent experimental observations.

Au/Pd/Ti and Au/Ti/Pd ohmic structures to thin p+-GaAs layers have been investigated for use as contacts to the base region of HJBTs. The Au/Pd/Ti contact system yielded specific contact resistivities at or above 2.8 × 10-5Ωcm2. Heat treatments up to 8 minutes at 380°C caused only limited interaction between the metallization and the semiconductor. The metal penetrated to a maximum depth of ≃2nm. Specific contact resistivity values less than 10-5Ω2 were achieved using the Au/Ti/Pd (400/75/75nm) scheme. The nonalloyed Au/Ti/Pd contact showed the best combination of electrical and structural properties with a contact resistivity value of 9 × 10-6Ωcm2 and Pd penetration of the GaAs epilayer to a depth of ≃30nm.

Measurements of the drift mobility μ of photo-excited electrons in n-type hydrogenated amorphous silicon (a-Si:H) as a function of light intensity are reported. The value of μ increases as the quasi Fermi level is moved closer to the transport states in accordance with the multiple trapping theory. The drift mobility decreases with increasing doping as well as with an increase in the concentration of metastable dangling bonds defects by strong light exposures. This decrease in μ between 300 and 360K can be explained by a corresponding decrease in the microscopic mobility, by an increase in the density of tail states within 0.35eV below the electron mobility edge, or by a combination of both these effects.

Thermoelectric properties of polycrystalline Bi2(Te1-xSex)3 (0.05 ≤ × ≤ 0.25), fabricated by mechanical alloying and hot pressing, have been investigated. Formation of n-type Bi2(Te0.9 Se0.1)3 alloy powders was completed by mechanical alloying for 3 hours at ball-to-material ratio of 5: 1, and processing time for Bi2(Te1-xSex)3 formation increased with Bi2Se3 content x. Figure-of-merit of Bi2(Te0.9Se0.1) was markedly increased by hot pressing at temperatures above 450°C, and maximum value of 1.9 × 10-3/K was obtained by hot pressing at 550°C. With addition of 0.015 wt% Bi as acceptor dopant, figure-of-merit of Bi2 (Te0.9Se0.1)3, hot pressed at 550°C, could be improved to 2.1 × 10-3/K. When Bi2(Te1-xSex)3 was hot pressed at 550°C, figure-of-merit increased from 1.14 × 103/K to 1.92 × 10-3/K with increasing Bi2Se3 content x from 0.05 to 0.15, and then decreased to 1.30 × 103/K for x = 0.25 composition.

When a biomaterial is implanted into the body, blood proteins adsorb on its surface and subsequently cells adhere via the protein adlayer. Thus, the understanding of protein adsorption and conformational change on the biomaterial surfaces is of great importance to control the biocompatibility such as antithrombotic properties and cell adhesion behaviors. In this study, we synthesized hydroxyapatite (HAp) and carbonate apatite (CAp) by a wet method. Then we successfully fabricated the HAp and CAp sensors for QCM-R by an electrophoretic deposition method. Adsorption behavior of proteins on the bone substitute material can be monitored by using these apatite sensors. Bovine serum albumin and fibrinogen were employed for the model proteins, and monitored the adsorption behavior on the HAp, CAp and reference gold (Au) sensors by the QCM-R technique. As a result, we revealed that fibrinogen and bovine serum albumin adsorbs on the gold surface by hydrophobic interaction, and adsorbs on the HAp and CAp surfaces mainly by electrostatic force. Besides, we revealed that fibrinogen adsorbs on the Au surface more rigid than on the HAp and CAp surfaces while bovine serum albumin adsorbs on the HAp and CAp surface more rigidly than on the Au surface.