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Spatial non-uniformity of the dissociative hydrogen atom (H0) production has been investigated in a large negative ion source (JAEA 10 A source) with the electron energy distribution function (EEDF) obtained by a Monte-Carlo simulation code for electron transport in 3D3V (three dimensional real and velocity) space. It has been shown that the H0 production rate becomes larger in the upper region (one side in the longitudinal direction) of the source chamber. This spatial non-uniformity of the H0 production profile is mainly explained by the non-equilibrium features of the EEDF in the upper region, i.e., the EEDF consists of thermal electron component with kinetic energy [variant_greek_epsilon] < 25 eV and fast electron component with energy [variant_greek_epsilon] > 25 eV in the upper region, while the EEDF mainly consists of only thermal electrons in the bottom region. These characteristics for the EEDF and the energy dependence of cross-sections for dissociation and dissociative ionization processes lead to the non-uniform profile of the H0 production. The above numerical results of the spatial H0 non-uniformity are validated and confirmed by comparisons with those by spectroscopic measurement. It has been clarified that the non-equilibrium (fast electron) component of the EEDF has a large contribution to the non-uniformity of the H0 production rate. [ABSTRACT FROM AUTHOR]

The production and transport processes of H0 atoms are numerically simulated using a three-dimensional Monte Carlo transport code. The code is applied to the large JAEA 10 ampere negative ion source under the Cs-seeded condition to obtain a spatial distribution of surface-produced H- ions. In this analysis, the amount of H0 atoms produced through dissociation processes of H2 molecules is calculated from the electron temperature and density obtained by Langmuir probe measurements. The high-energy tail of electrons, which greatly affects H0 atom production, is taken into account by fitting a single-probe characteristic as a two-temperature Maxwellian distribution. In the H0 atom transport process, the energy relaxation of the H0 atoms, which affects the surface H- ion production rate, is taken into account. The result indicates that the surface H- ion production is enhanced near the high-electron-temperature region where H0 atom production is localized. [ABSTRACT FROM AUTHOR]

Describes a developed tungsten/titanium nitride (TiN) bilayer interconnections. Details on the minimum thickness of TiN; Information on the silicidation rage in the tungsten/TiN/silicon system; Experiment and result of the study.

Investigates the effects of interfacial oxide on defect generation and regrowth rate in solid-phase epitaxy of amorphized silicon. Influence of interfacial oxygen on a solid-phase epitaxy process; Evaluation of interfacial oxide layer; Reduction of interfacial oxygen concentration by silicon ion implantation.