One-dimensional simulation of the traveling liquidus-zone (TLZ) method is carried out in order to obtain growth rates. The simulation agrees well with experimentally obtained concentration profiles in solid. It is found that the conventional TLZ model precisely predicts the spontaneous growth rate, within an error of 3% in the region of the low temperature gradient.

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A recently developed 3D global model was extended for the case in which the crystal and crucible are rotating. 3D global simulations were carried out for a small CZ-Si furnace in a transverse magnetic field. Most 3D features of the thermal field in the furnace were reproduced. The effect of crystal rotation rate on the melt-crystal interface shape was analyzed.

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Reaction at the interface between Ba-doped silica crucible and Si melt for Czochralski Si (CZ-Si) crystal growth has been studied. It is found that appropriate Ba-doping in a silica crucible results in a remarkable effect on suppression of formation of the so-called brownish rings at the interface. This kind of silica crucible is expected to enhance the growth yield in CZ-Si crystal growth.

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Time evolution of Marangoni flow instability of molten silicon has been investigated at high Marangoni number region by measuring temperature oscillation using thermocouples and surface oscillation using phase-shift interferometry with a combination of a wavelet transformation. The relationship between azimuthal wave number m and aspect ratio F was experimentally clarified. Through surface oscillation observation, instability with various frequency was found to coexist.

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Effects of the ACRT for crystal rotation on melt convection and crystal-melt interface shape were investigated by two-dimensional time-dependent numerical simulation. The difference of the initiation time between the ACRT for crystal rotation and for crucible rotation, Δt_<ACRT>, was set to 0〜65s. It was found to take a long duration time for the melt moving from around the melt surface to the interface when the Δt_<ACRT> was set to 25s compared to the case of 65s.

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To grow InGaSb bulk crystals with uniform composition, the relationship between the composition and growth rate were measured. The samples was GaSb(seed)/InSb/GaSb(feed) sandwich structure and Te impurity was doped in the InSb. Thermal pulses were introduced during growth to form the Te striations. Experimental results indicated that lack of GaSb(feed) caused the decrease of growth rate and the increase of In composition. By adjusting the cooling rate, In_<0.03>Ga_<0.97>Sb homogeneous crystal were grown.

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In the growth from a melt of such mixed crystals as In_xGa_<1-x>As and Si_<1-x>Ge_x, crystal growth goes on due to supersaturation caused by the mass transport even if heat reduction from the interface is insufficient. This growth mode can be distinguished from the supercooling induced growth in such crystals as Si, GaAs InP and so on. We have succeeded in producing two growth modes in the growth of In_xGa_<1-x>As and compared them from the view point of single crystallization. As a result, single crystals can be grown more easily in the supercooling induced growth mode. Here, we report such experimental results and we discuss the effect of local solute inhomogeneous distribution on the polycrystallization.

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The THz-wave intensity generated from the low carrier density GaSe (10^<10>cm^<-3>) in the frequency below 1THz is greater than that from high carrier density GaSe (10^<14>cm^<-3>), this may be due to free carrier absorption.

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One of the promising organic nonlinear optical crystals, DAST is expected to be applied for electro-optic sampling and tera-herts radiation through differential frequency generation. DAST crystal was usually fabricated by solution method using a methanol as a solvent. Thin crystal was prepared to make its waveguide, though, we need to fabricate a serially grafted waveguide where DAST is only a small part of the waveguide and the rest of it will be a transparent polymer waveguide. We will discuss about the crystal growth and the waveguide fabrication of DAST through photo-bleaching.

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We developed new crystallization and growth techniques for protein crystals. Effective crystallization was confirmed by applying an intense femtosecond laser. We call this process Laser Irradiated Growth Technique (LIGHT). Protein crystals were obtained by LIGHT from normally uncrystallized conditions. Solution stirring technique is effective for growing large, high-quality protein crystals.

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Mechanisms of defects incorporation have to be clarified to grow high quality single crystals. To approach this problem, elementary growth processes, such as 1) movement of elementary growth steps and 2) diffusion of solute molecules in the vicinity of crystal surfaces have to be observed in situ. Recently, we have succeeded in observing these elementary processes by advanced optical microscopy utilizing large size of protein molecules.

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Organic semiconductor materials such as oligothiophene etc. are interesting for highly opto-electrical properties. The charge carrier mobilities of these small molecules are dependent on the molecular orientation and the morphology of thin films. Then, we applied to control the molecular orientation in thin films, producing films with strong anisotropy of the mobility. We prepared the highly oriented thin films, in which molecules uniaxially aligned parallel to anisotropic polymer templates.

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Basic electrical characteristics of organic semiconductor thin-films are investigated using in-situ field effect measurement and conductive AFM probe. We discussed the carrier transport mechanism of organic semiconductor films and its application to opto-electronic devices.

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Today, amorphous semiconductor films of Te-based and Sb-based alloys are utilized for rewritable optical disks, representatively DVD-RAMs. Here, the author will review the phase-change mechanism enabling the fine properties of the present optical disks, such as short laser-crystallization time of several ten nano-seconds and long life over several ten years.

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We have proposed and demonstrated a memory transistor that has two functions of nonvolatile memorizing and electron current controlling (switching) using phase change (PC) and nanometer size effects. We have prototyped the transistor using the PC channel, that was made of GeSbTe with a thickness of 50nm. We also describe fine crystallizing for the primary functions of the transistor.

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Dynamic observation system for high speed crystallization has been developed using blue LD, high speed LD driver, streak camera and precise timing controller. We succeeded to observe the crystal growth process on GeSb phase change films dynamically.

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The epitaxial lateral overgrowth (ELO) was performed on {001} oriented InP by liquid phase epitaxy at constant growth temperature (650℃). In this work, line and space (L & S) and L-shaped patterns were formed on substrates before epitaxy. In L & S pattern, etch pits were observed on open seed region and coalescence region. However, in L-shaped pattern, etch pits were observed only at the open seed region. Then, the mechanism of coalescence of ELO layers is discussed in L & S and L-shaped patterned.

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The dislocation-free ELO layers were formed on InP(001) surface with L-shaped open seed area by using LPE method. When L-shaped open seed area was modified by rotation and facing, large sized ELO layers were obtained. Carrier scattering mechanisms in various kinds of ELO layers will be discussed in view of the dislocation scattering.

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In-doped PbTe epitaxial layers were grown on PbTe undoped substrates by LPE via TDM-CVP method and the doping characteristics has been investigated. It is shown that the broad contact pn junctions with In-doped n type layers improve the lasing characteristics compared with those of Bi-doped and undoped samples. We proposed that In and Bi are suitable as the donor impurities for injection and active layers in laser diode structures, respectively.

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InAs_xSb_<1-x> ternary layers were grown on GaAs(001) substrate by hot wall epitaxy. When increasing As reservoir temperature, the growth rate decreased from 1.1 to 0.5μm/hr. It is found that three dimensional growth has been observed due to large lattice mismatch between the substrate and the ternary layers. By increasing As reservoir temperature from 220 to 280℃, the compositional ratio (x) of InAs_xSb_<1-x> layers can be controlled in the range between 0.02 and 0.81.

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ZnO layers were grown on GaAs(111)B substrates by plasma assisted MBE. The c axis of ZnO was nearly perpendicular to (111) plane of GaAs, and the angle between the c axis and the [111] direction was determined by reciprocal lattice mapping. Effects of O/Zn beam flux ratio on the properties of grown layers were also studied.

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Area-selective regrowth by molecular layer epitaxy was applied for the fabrication of sidewall GaAs tunnel junctions. These tunnel junctions have shown record peak current densities of up to 37000A/cm^2 at RT. It is also shown that the tunnel junction characteristics have been improved by AsH_3 surface treatment just prior to regrowth.

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Reentrant RHEED intensity oscillation (RO) observed during low temperature MBE growth of GaAs has been explored by RHEED rocking curves observation during growth. Time evolution of surface coverage obtained based on dynamical diffraction calculation reveals that the origin of dumped-RO around 400℃ is due to rapid roughening, which takes place within first monolayer growth on C(4x4) surfaces.

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Combination sources molecular beam epitaxy, which utilizes solid and gas phase sources, has been tried with Si as a solid source and monomethylsilane as a gas source for homoepitaxial SiC deposition. SiC film altered its surface morphology, thus, growth mode depending on the surface reconstruction tuned with a Si flux impinging on the growing film surface simultaneously with monomethylsilane.

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Metalorganic chemical vapor deposition of zinc oxide film was performed in a high magnetic field of 10 tesla with diethyl zinc and water vapor as starting materials. Reducing in deposition rate, particle size and suppression of leaflet like structure were observed as the effect of magnetic field. These effects can be understood by assuming a model where the mobility of the adsorbed atoms on the growing crystals is reduced by the magnetic field due to Lorentz force.

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ZnSSeO quaternary alloy was grown on GaP and GaAs substrates by MBE and controllability of group VI composition was investigated. O composition was increased by reducing S and Se source temperatures. The maximum O composition of more than 10% was achieved without phase separation regardless of large difference in bond length among ZnS, ZnSe and ZnO.

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Low temperature growth of 3C-SiC has been studied by LPCVD. At 720-760℃ it was grown from MMS (monomethylsilane) on Si (111) 4° off substrate, which was heated by direct current. 10^<-8> Torr of MMS was introduced in a chamber with a pressure of 10^<-8> Torr through a gas cracking furnace. At the substrate temperature of 760℃ high crystallinity was reached.

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Atom-mixing processes at metal/semiconductor interfaces are studied for Al/Si and Au/Si systems, by using the first-principles calculations. It is shown that Au atoms can diffuse into Si substrate with a little potential barrier, while Al atoms remain on the Si surface. This difference originates from the difference of electronegativity between Au and Al atoms.

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Boron monophosphide (BP) films were grown on silicon (100) by MOCVD. The layer grown on silicon (100) surfaces was found to be a single crystal BP with cubic structure by measuring X-ray diffraction. This paper describes the growth conditions and the evaluation of BP films obtained.

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We experimentally clarified the relief mechanism of a double-layer structure buffer. Furthermore, we proposed the triple-layer structure buffer containing an ultra-thin high Ge composition layer. And the high PVCR of 〜50000 has been obtained at room temperature and it has been suggested that the triple-layer buffer has better crystalline quality.

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InAs quantum dots were grown on mesa-grooved (100) GaAs substrates. The distribution of InAs (lots depended strongly on the width of mesa-grooves; InNs dots array where grown on the ridges with width less than 200nm.

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The effect of growth interruption on the properties of InAs/GaAs quantum dots on GaAs(001) substrates by molecular beam epitaxy (MBE) has been studied using atomic three microscope (AFM) and photoluminescence (PL) technique. The size of InAs dots increased with increasing the interruption time, although the density of InAs dots decreased as the interruption lime was increased.

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The stimulated Raman gain coefficient and the optical loss in GaP/AlGaP heterostructure waveguides and Si slab waveguides are measured in 1.5μm region, respectively. The optical losses of the waveguides are estimated from finesse measurement.

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ZnS thin films were epitaxially grown on Si(100) wafers by the two-source vacuum evaporation method. There were only 200 and 400 peaks in the XRD patterns. The twin structure was not found in the RHEED patterns and the free exciton emission was observed in the photoluminescence spectra, indicating the high quality of films.

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Molecular beam epitaxy (MBE) was observed using in situ reflectivity monitor system. The thickness of the grown layer is able to be controlled by the real time monitor of the resonant wave length of the cavity.

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GaSe films were grown on GaAs(001) substrates by molecular beam epitaxy. We studied the growth condition of the GaSe and the relation between surface morphology of the GaSe and the growth condition. Ga_2Se_3 was grown under high VI/III ratios and high growth temperatures.

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