This paper considers the possible commercial viability of applying the moving particle semi-implicit (MPS) method to avalanches. The MPS method is a powerful tool for reproducing the flow phenomenon with large-scale surface deformation. In order to apply this method to snow avalanches, we modified the original model to introduce constitutive equations of Bingham fluid, dilatant fluid and the erosion–deposition process. The modified model was applied to some cases and evaluated through comparison with experimental results and observed data.

The author reports on idea of momentum effect of gaseous beam particles as to thin film epitaxial crystal growth such as molecular beam epitaxial growth or metal organic chemical vapor deposition epitaxial growth on stiffness of epitaxial growth thin film. The author presented that liquid glass encapsulation squeeze compression effect of liquid-glass-encapsulation Czochralski technique (LEC) crystal growth [Y.Saito, presented at the 10th Int. Conf. on Crystal Growth, 1992], third element different from crystal matrix elements [Y.Saito, presented at the 9th Int. Conf. on Ternary and Multinary Compounds, 1993], light momentum pressure of substance cooling thermal cycle [Y.Saito, presented at the 1st Int.Symposium on Laser and Optoelectronics Technology & Applications, 1993] can yield firmly binded bonds of substance elements. On the other hand, collisions of particles sputtered from solid target slabs [Y.Saito, presented at the 2nd Int.Symposium on Sputtering & Plasma Processes, 1993] or accelerated ions or particles evaporated from molten metals with themselves on the thin films can yield binded bonds. It was shown that internal compression in a crystal by ion implantation in crystal cell lattices can make the refractory state to gas phase chemical attack.[Y.Saito, in the Materials Research Society Symposium Proc. Vol. 279, pp. 135–140.] From these results, we can consider momentum effect at collision on binding state. After collision binding, internal compression by thermal transition variation in a multilayer structure during cooling thermal cycle influences binding stiffness.

Threshold voltages of Si-implanted gallium arsenide (GaAs) MESFETs depend on not only wafer crystallographic characteristics, but also MESFET fabrication processes. When the position of the orientation flat was changed to improve mechanical shock tolerance, it was found that Vth varied on the wafers due to a crystallographic orientation effect on the Si implantation. Thus, we investigated Vth distributions on wafers of several different Si implantation orientations. It was confirmed that Vth largely varies according to Si-implantation orientations.

It was observed that thin metal (catalytic metal: platinum) penetrated into a interface between a chemical vapor deposition (CVD) silicon dioxide film and a Si–implanted electric thermal furnace, on the way to carrying out experiments on alloyed ohmic–metals with Si–implanted electrically conductive n–type GaAs crystal layers in order to obtain stable and uniform ohmic contact electrodes of low specific ohmic contact resistances for metal–semiconductor field–effect–transistor arrays as a observation tool of semi–insulating GaAs–crystal crystallographic uniformity.

The author did experiments on ohmic contacts between alloyed goldgerumanium (AuGe) thin film systems and Si–implanted n–type GaAs crystal conductive layers on semi–insulating wafers in order to obtain stable ohmic contacts for source–drain electrodes of Si–implanted metal–semiconductor field–effect–transistor arrays as the tools of investigating semi-insulating GaAs crystallographic–characteristics uniformity. Hot–stage–alloyed low–Ge–content (content in charged AuGe wire: < a few wt.%) AuGe/Au films and GaAs crystal n–type Si–implanted layers showed smooth metallic surface morphology (like gold reflection) and low specific ohmic resistivity (≃10exp.−6 Ω/cm2) (by G.S.Marlow and M.B.Mukunda method) at Room temperature on the condition of typical 0.25 X 10exp.13/cm2− 1 X 10exp.13/cm2 Si dosage at 100keV–200keV and 850°C-15 min capless annealing in 2.7 Torr AsH3+Ar atmosphere for S.I GaAs crystal wafers.

This paper reports the variation of carrier concentration depth profile in Si-implanted channel conductive layers of liquid- encapsulated-Czochralski- technique (LEC) grown GaAs crystals, the Vth scattering amplitude variation and the averaged Vth variation before and after phospho-silicate-glass (PSG) cap annealing of high-dose-Si-ion implanted crystal layers. Furthermore, the PSG-cap-annealing Vth variation difference between the As-rich LEC crystal and the near-stoichiometric LEC crystal is presented. These results, and carrier depth profile of Si-implanted active layers in LEC GaAs crystals through model of implanted Si atom move (like diffusion) and Si atom capture of a crystal lattice and siteing on lattice are discussed.

The author observed that both high-current-ion-beam and low-accelerationvoltage arsenic-implanted polycrystalline silicon-film surfaces are resistant to radical-fluorine-gas-etching. If we accept the simple assumption that a depth profile of concentration distribution of the implanted high-dose As atoms in polycrystalline Si film can be expressed with a standardized distribution function in the previous report of S. Furukawa, H. matsumura, and H. Ishiwara [Jpn. J. Appl. Phys. 11, 134 (1972)], we can take the premise that the chemical bonding reaction itself between radical-fluorine atoms and silicon atoms is prevented rather than that the covering of an arsenic- metal thin layer like amorphous state prevents the chemical bonding- reaction. We present a model of the prevention Si-F bond formation by high-dose arsenic implantation at low acceleration voltage. The model seems to be related to potential barrier increase and lattice vibration suppression for electromagnetic force-phonon interaction.

The fabrication process of high current arsenic (As) ion implanted poly-silicon (Si) gate and source-drain (SD) electrode Si n-channel metal-oxide-semiconductor field-effect-transistor (MOSFET) was examined. Poly-Si film n-type doping was performed by using high current (typical current: 2mA) and relatively low acceleration voltage (40keV) As ion implantation technique (Lintott series 3). It was observed that high dose-As implanted poly-Si films as is show refractoriness against radical fluorine excited by microwave. Using GCA MANN4800 (m/c ID No.2, resist: OFPR) mask pattern printing technique, the high current As ion implantation technique and radical fluorine gas phase etching (Chemical dry etching: CDE) technique. the n-channel poly-Si gate (ps=∼L00ft/o) enhancement MOSFETs(ps-source-drain = =50n/o, SiO2 gate=380A) with off-leak-less were obtained on 3”Czochralski-grown 2Ωcm boron-doped p-type wafers (Osaka titanium). By the same process, a 8-bit single chip μ-processor with 26MHz full operation was performed.

We report drain-current (Id) deep level transient spectroscopy (DLTS) spectra and liquid-encapsulated-Czochralski-technique (LEC) GaAs crystal effect on low-frequency-oscillation (LFO) of wide gate (400-μm) Si-implanted GaAs metal- semiconductor field- effect- transistors (MESFETs). In the range of this experiment we could not find distinguishing DLTS peaks surely to be linked with Id-LFO of the MESFETs. Stoichiometric-melt growth LEC-boules showed relatively large Id-LFO phenomena. As-rich-melt growth LEC-boules showed tolerance to Id-LFO. We conclude that Id-LFO is not directly linked to deep centers themselves but interaction between deep centers and potential profiles and electrons. Stability of potential profile or band profile depends on “pinning’ center, which affects Fermi-level or quasi-Fermi-level stability. ‘Pinning’ center such as EL2s of ‘LEC GaAs crystals” is essential.