ZnS epitaxial layer on CaF_2 (100) is grown by the Solvent Evaporation Epitaxy method using PbCl_2 as a solvent. To avoid ZnS decomposition, the growth reaction is carried out under sulfur-enriched atmosphere. We have obtained ZnS layer at temperatures higher than 600℃.

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23aB12 The growth process of SiC-CVD was investigated by thermogravimeter, using MTS. The temperature dependence and MTS partial pressure dependence of SiC growth rate were examined. The partial pressure dependence was explained on the basis of the two sites competitive adsorption model.

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Plasma CVD of silicon carbide was carried out from MTS or MMeSi. Its growth kinetics was investigated on the point of view of plasma reaction and optical emission spectroscopy for the precursor. Each source material indicates the different precursor and the composition of the films can be controlled by plasma power density.

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a-SiC: H was deposited on Si (100) substrates by Plasma CVD. The bonding structures in this film were analyzed using FT-IR, and the crystal structure were analyzed by x-ray diffraction. Ln this result, a-SiC began to crystallize to 3C-SiC at 1300℃ for after-annealing of one hour.

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Carbon micro-coils were prepared by the catalytic pyrolysis of acetylene containing a small amount of thiophene. The effects of the preparation conditions on the coi1 morphology were examined in detail, and the growth mechanims was discussed.

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The shear modulus of coiled carbon fibers, which were synthesized by thermal decomposition of acetylene gas, was measured with a micro-balance and a micro-manipulator. Electric resistivity of the coiled carbon fibers could be also measured. Cross section area of the fibers has been evaluated by using SEM.

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Control of particle size and particle size distribution in batch crystallization, are very important to improve the product quality. Product quality affect the solubility and pharmaceutical fomulation process, eg. Particle flowability, tablet compressibility, powder filling. The following are successful examples to control the physical properties in large scale. The simple scale up method for batch crystallization is described. This method is based on Z factor which corresponds to minimum agitation speed for suspension. It can control the particle size, particle size distribution and reaction rate for scale up.

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An optical microscope was specially designed and constructed for in situ observation of the protein crystallization under high magnetic field. The effect of the magnetic field of 11T was to decrease the growth rate of tetragonal lysozyme crystals. The magnetic field effect on the dissolutionprocess of the crystal was also investigated.

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The effect of a magnetic field on HEW lysozyme crystals was studied using X-ray structure analysis. Both crystals of tetragonal form were grown with and without the high magnetic field. The two structures are nearly identical with the r. m. s. deviation 0.5Å. The changes of the side-chain of amino acid within C-terminus were found out at the interface between adjacent molecules. This difference will be hereafter discussed by use of the structure of orthorhombic crystal.

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The huge step formed by changing temperature and the strength of magnetic field on the surface of a tetragonal crystal of hen egg-white lysozyme was investigated by scanning electron microscopy. It was found that the huge step consisted of thick layers which had a thickness of a few micrometers, and there were two kinds of surface at equivalent sites. We consider that the sudden changes in temperature and magnetic field allow new aspects to be observed.

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Growth rate of orthorhombic lysozyme crystals was measured in situ under 0.1 and 100 Mpa. High pressure effect was to decrease the growth kinetics of orthorhombic crystals as in the case of the tetragonal ones.

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Crystallization behaviour of n-hexadecane in o/w emulsion have been studied by ultrasonic velocity measuremants and differential scanning calorimetry. In comparison with the results of the o/w emulsion systems with those of the bulk systems, the following results were obtained; (a) the additives accelerated the nucleation in the emulsion systems, (b) the rates of crystal growth were retarded caused by the additives.

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Phase behavior of binary mixture system of fats, SOS-SSO, in which a compound has been formed at 1:1 mixture, has been studied by differential scanning calorimetry, X-ray diffraction and Fourier transformed infra-red spectroscopy. The most impotant fact is that, during the melt crystallization. The less stabilized form, compound system of SOS:SSO=1:1, has been crystallized faster than the more stabilized form of each component system of SOS and SSO in the same polymorphs.

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An inhibitory effect of Mg and Zn on hydroxyapatite crystal growth was quantitatively measured. The growth rates of hydroxyapatite (0001) face were measured by moire phase shift interferometry. The growth rates decreased by 70% in a concentration range from 0 to 1.5 mom of Mg and from 0 to 1.5×10^<-3> mM of Zn. It was found that Zn was about 1000 times effective than Mg in inhibiting hydroxyapatite crystal growth. The relationship between growth rates and additive concentrations was fitted by Langmuir adsorption isotherm in a range from 0 to 7.5× 10^<-3> mM for Zn, and in a range from o to 1.5×10^<-1> mM for Mg. It was understood that Zn and Mg inhibited hydroxyapatite crystal growth by surface adsorption. However, the relationship was not fitted by Langmuir adsorption isotherm in a range from 1.5×10^<-1> to 1.5 mM for Mg, suggesting that Mg substitutes for Ca sites of hydroxyapatite crystal.

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It was found that the surface potential of the aggregate of calcium phosphate clusters was positive in solutions containing 2.5mM CaCl_2, 1.0 mM H_3PO_4. And buffered at pH 7.40 with KOH. This suggests that the surface of the cluster is positively charged, being consistent with the cluster growth model that the chemical composition of the cluster is Ca_9 (PO_4)_6.

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A novel method has been developed which makes it possible to independently control temperature and stress current of an interconnect line during TEM observation. Using this technique, it was revealed that the resistance of the interconnect increases with the growth of the voids which appeared at each side of the boundary of one Al bamboo grain due to electromigration. This result shows that the present method can be very effective for studying the EM failure mechanism.

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If the dendritic growth mechanism is cleared. The dendritic deposit of lithium could be restricted. In this investigation, STM (scanning tunneling microscopy) and computer simulation study on lithium electrodeposition has been performed in order to investigate a dendritic growth of lithium.

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Single crystal growth of nitrides (AlN, GaN, InN) under high pressure and high temperature conditions has been tried using a diamond anvil cell and YAG laser heating system. Flushing of exothermic reaction between metal gallium and supercritical nitrogen in high temperature was observed. Crystals of GaN in 〜μm size can be easily obtained. Results of AIN and InN will be also reported.

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Single crystal growth of oxides under high pressure and high temperature conditions has been tried using a diamond and cell and YAG laser heating system. Growth by means of a flux method in high pressure and hydro-thermal method has been tried to obtain crystals of various kinds of oxides, such as icosahedral B_6O and Ni_2SiO_4.

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Crystaliization of L-a1anine and lysozyme were observed under the magnetic field. For lysozyme, the produced crystals stood in a row with the field. For L-alanine, the morphology was same as with additive ions.

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Crystal growth at high temperatures has been studied by in-situ observations with a Mach-Zehnder interferometer, and the concentration gradient around the crystal has been examined during the growth and dissolution.

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Renaissance and progress in heteroepitaxial growth of group III nitride semiconductors on highly-mismatched substrates in the past quarter century have led to high-performance blue and green light emitting diodes, violet laser diodes and high-speed transistors based on nitrides.

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Progress in Si crystal and wafer technologies is discussed in terms of single crystal growth, wafer fabrication, epitaxial growth, gettering, 300mm and SOI.

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I review microscopic calculations that reveal elementary atomic processes in semiconductor epitaxial growth. The calculations are based on the density functional theory with the local density approximation (LDA) or the generalized gradient approximation (GGA). I try to convince you that the first-principles calculations are powerful tools to clarify the mechanisms of epitaxial growth. Adsorption and diffusion of a Si adatom on the terrace and near the steps on Si(100) surfaces are mainly discussed.

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The global analysis of heat transfer In the CZ crystal growth furnace was carried out. Especially, the effects of internal radiation and crystal rotation on the melt/crystal Interface shape was Investigated numerically.

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The effect of now in RalO_3 melt in a magnetic field was examined. Two different atmosphere (nitrogen 100% atmosphere and reduced atmosphere) were used for the experiment. It was found that in reduced atmosphere the effect was appeared to be strong.

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Behavior of BaO-P_2O_5 class melt applied with high magnetic field was studied. Flow change of melt by application with magnetic field was not observed, but magnetic field acted on bubbles in glass melt. By application with the field the number of bubbles decreased. The phenomenon was observed at the field strength of 〜0.4T. And almost of the bubbles were disappeared at 1.4T. This phenomenon is reversible, and the number of bubbles increased with decreasing the field strenght.

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Double crucible Stepanov technique has been developed to grow a single crystal of strontium barium niobate (SBN). The grown SBN crystals are profiled by the die shape and free of striation.

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Single crystals of refractory borides were prepared by the RF-heated floating zone method. Their crystal quality was estimated from the high temperature hardness. The growth directions were consistent with anisotropy of the hardness, and tried to be controlled without the seed crystals.

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Using CF_4 gas as a scavenger, growth method of calcium fluoride single crystals with high transparency in VUV region has been studied. By experiments under several conditions of heating the raw material, the transparency of resulting crystals depends on the following two factors. One is the temperature at the change to a vacuum from CF_4 atmosphere and the other is the dilution of CF_4 with inert gas such as Ar.

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We studied the effects of doping of alkali metals (Na, Kb, Cs) upon the perfection of C-Z grown KCI crystals. It IBS found that Rb doping remarkably suppressed the subboundary formation.

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The relation between supersaturation and KDP crystal growth rate was investigated under the same condition. As a result, the relation was linear and high speed growth rate of over 80mm/day was obtained.

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Transport mechanism of oxygen in silicon melt under transverse magnetic fields was clarified using three-dimensional and time-dependent calculation. The calculation clarified the following results. 1) Oxygen in grown crystals is dissociated from side wall of a crucible. 2) Oxygen which was dissolved from side wall of a crucible is transferred parallel to magnetic fields. 3) Oxygen is incorporated from a region which settled parallel to magnetic fields to solid-liquid interface.

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We observed a wave-like temperature distribution moving in azimuthal directions on a surface of a silicon melt layer 8mm in depth and 126mm in diameter. This temperature distribution is discussed by view points of hydrothermal wave and Benard cell.

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We developed new crystal growth method (EMCZ) using electromagnetic force in order to control of oxygen concentration in silicon crystals. Using this method, the oxygen concentration in silicon crystals was continuously changed from 1x10^<17> to 1x10^<18> cm^<-3> with the increase of melt rotation rate. This mean that EMCZ method can achieve homogenization of oxygen concentration along the pulling direction with gradually changing the melt rotation rate.

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Monte Carlo simulation (MC) and cluster variation method (CVM) based on lattice-gas models are carried out to study phase transition. To study actual systems as quantitatively as possible, molecular dynamics (MD) potentials are mapped onto lattice-gas models by using the potential renormalization technique proposed by Ohno. We find that the linear expansion coefficient of perfect crystals and the transition temperatures are greatly improved when compared with the case of using the MD potential directly on the lattice.

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To investigate the effect of solute and volume expansions on the solution convection, numerical analysis were performed as a function of gravity level. Under 1g condition, both expansions affected the convection flow. By decreasing the gravity, the solute expansion became dominant.

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Aluminum single crystals with a low dislocation density were grown by the strain-annealing method from ultra-high purity materials. The nature of dislocation and the dislocation density were 60° dislocation and lx10^3 cm^<-2>, respectively. These results are similar to those in high purity aluminum reported previously.

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The pressure controlled solution growth method has been newly developed and applied to the growth of bulk GaN single crystals. Bulk GaN crystals with the size of from 7×7 to 10×10mm^2 could be reproducibly obtained and it wa8 found that they are single crystals oriented to (0001) by X-ray diffraction measurement. From the TEM and PL measurements, they were found to be of good crystallinity.

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GaN were grown by blowing NH_3 gas bubbles onto a substrate that suspended in Ga melt at 95℃ for 4.5h under atmospheric pressure. In the case of growth directly on a sapphire substrate, grown crystals show columnar shapes. On the other hand, GaN epitaxial layer of 2 - 3μm is grown on a GaN substrate that is preformed on a sapphire by MOVPE.

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In-situ observations of the thermal diffusion field around a growing D_2O-ice crystal were carried out under both the 1G and μG conditions, using a Mach-Zehnder interferometer. Development of thermal diffusion field during the melt growth was clearly observed.

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Melting transition at the grain boundary of ice bicrystal was studied by an ellipsometry. The interference of transmission light was detected below the bulk melting point. It may be related to the existence of interfacial transition layer.

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Ice crystal growth from the AFGP solution was observed in-situ using a directional growth method. Driving force for the ice crystal grown in AFGP solution was directly measured.

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Flocculation of polystyrene latex particles in water was studied by using the dynamic light scattering method. KCl concentration at which the flocculation started increased with the particle concentration and became constant when the particle concentration was 0.02-0.18 wt%. Normalized flocculation rate increased with KCl concentration, and it also depended on temperature.

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Crystals of quinhydrone, which is a typical charge-transfer complex, composed of hydroquinone and p-benzo-quinone, can be produced by electrolytic oxidation of hydroquinone. In situ observation of the electrochemical crystal growth of quinhydrone was performed in a thin-layer cell filled with aqueous solution of NaCl. Hexangular prisms characteristic of quinhydrone were observed to grow at different places apart from the anode.

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