Abstract: The invention relates to a method for growing single crystals of barium titanate [BaTiO3] and barium titanate solid solutions [(BaxM1−x)(TiyN1−y)O3]. This invention is directed to a method for growing single crystals of barium titanate or barium titanate solid solutions showing the primary and secondary abnormal grain growths with increasing temperature higher than the liquid formation temperature, characterized by comprising the step for a few secondary abnormal grains to continue to grow at a temperature slightly below the critical temperature where the secondary abnormal grain growth starts to occur. The method for growing single crystals of barium titanate or barium titanate solid solutions according to this invention has the advantage of providing an effective low cost in manufacturing process for single crystals by using a conventional heat-treatment process without the need of special equipment.

Abstract: Reactive gas is released through a crystal source material or melt to react with impurities and carry the impurities away as gaseous products or as precipitates or in light or heavy form. The gaseous products are removed by vacuum and the heavy products fall to the bottom of the melt. Light products rise to the top of the melt. After purifying, dopants are added to the melt. The melt moves away from the heater and the crystal is formed. Subsequent heating zones re-melt and refine the crystal, and a dopant is added in a final heating zone. The crystal is divided, and divided portions of the crystal are re-heated for heat treating and annealing.

Abstract: In an annealing process in which laser light is irradiated to a semiconductor thin film, a refractive index of the semiconductor thin film after laser light irradiation is measured and conditions for the next laser light irradiation are adjusted based on the measured refractive index value. For example, laser light irradiation conditions are adjusted so that semiconductor thin films always have the same refractive index. As a result, the annealing can be performed under the same conditions at every laser light irradiation even if the laser light irradiation conditions vary unavoidably.

Abstract: The invention provides a method of treating a material to cause the material to evolve from one phase to a more ordered phase, the method comprising an operation of irradiating the material in which the irradiating particles are suitable, by their nature and by their energy, for inducing displacements of the atoms in the material towards positions that favor ordering of the material. Advantageously, the invention also provides apparatus for magnetically recording information, the apparatus comprising a material deposited on a substrate at a temperature of less than 350° C. and that has been subjected to irradiation with irradiating particles that are suitable, by their nature and their energy, for inducing displacements of the atoms in the material towards positions that favor relaxation of the material.

Abstract: A method for improving the toughness of a CBN product made by a high temperature/high pressure (HP/HT) process commences by forming a blend of an oxygen getter and CBN product-forming feedstock. The blend is subjected to a CBN high temperature/high pressure (HP/HT) process for forming a CBN product. The amount of oxygen getter in the blend is sufficient to improve the toughness of the CBN product. The resulting CBN product desirably has an oxygen content of less than about 300 ppm. Oxygen getters include Al, Si, and Ti. The HP/HT process is conducted in the absence or presence of catalytic materials.

Abstract: A crystal oscillator and method for manufacturing same including excitation electrode portions formed upon a crystal substrate and thus forming an excitation portion of the area defined between the electrode portions. Axis inversion portions possess an electrical axis (−X) opposite to the electrical axis (X) of the excitation portion, these axis inversion portions being formed within the crystal substrate at a position other than that of the excitation portion. A stable resonance frequency and filter frequency can be obtained even under conditions of ambient temperature fluctuation, by means of a relatively simple temperature compensation circuit, wherein handling is easy and no complicated adjustment is necessary, and low costs can be realized.

Abstract: The invention relates to a method for growing single crystals of barium titanate [BaTiO3] and barium titanate solid solutions [(BaxM1-x)(TiyN1-y)O3]. This invention is directed to a method for growing single crystals of barium titanate or barium titanate solid solutions showing the primary and secondary abnormal grain growths with increasing temperature higher than the liquid formation temperature, characterized by comprising the step for a few secondary abnormal grains to continue to grow at a temperature slightly below the critical temperature where the secondary abnormal grain growth starts to occur. The method for growing single crystals of barium titanate or barium titanate solid solutions according to this invention has an advantage to provide an effective low cost in manufacturing process for single crystals by using usual heat-treatment process without special equipments.

Abstract: A process for converting a polycrystalline ceramic material to a single crystal material includes the steps of doping at least a first portion of the polycrystalline ceramic material with a conversion-enhancing dopant having a +6 valence state in the unfired ceramic material and heating the polycrystalline ceramic material to convert at least a second portion of the polycrystalline ceramic material to a single crystal ceramic material. Preferably, the ceramic material is alumina and the conversion-enhancing dopant is molybdenum or tungsten.

Abstract: A crystallization apparatus and method that is adapted to crystallize a semiconductor using a non-vacuum process. In the apparatus and method, laser beams are irradiated onto a substrate to grow a crystal unilaterally from the side surface of the substrate. Grain boundaries are minimized under the air atmosphere, so that a crystallization of the substrate can be made in a non-vacuum state to improve the throughput.

Abstract: A method of growing a nitride semiconductor layer, such as a GaN layer, by molecular beam epitaxy comprises the step of growing a GaAlN nucleation layer on a substrate by molecular beam epitaxy. The nucleation layer is annealed, and a nitride semiconductor layer is then grown over the nucleation layer by molecular beam epitaxy. The nitride semiconductor layer is grown at a V/III molar ratio of 100 or greater, and this enables a high substrate temperature to be used so that a good quality semiconductor layer is obtained. Ammonia gas is supplied during the growth process, to provide the nitrogen required for the MBE growth process.

Abstract: According to the invention, a complex (M or M′) formed by stacking in a closely contacted state a single crystal &agr;-SiC base material (1) and a polycrystalline plate (2) which is produced into a plate-like shape by the CVD method with interposing an intermediate layer (4 or 4′) containing Si and O as fundamental components, such as silicon rubber between opposing faces of the two members (1) and (2) in a laminated manner is heat-treated at a temperature of 2,200° C. or higher, and under a saturated SiC vapor pressure, thereby causing polycrystal members of the polycrystalline plate (3) to be transformed in a same direction as single crystal of the single crystal &agr;-SiC base material (1) to integrally grow single crystal. Therefore, single crystal SiC of a high quality in which crystal defects and distortion are prevented from occurring and micropipe defects hardly occur can be produced easily and efficiently.

Abstract: In an annealing process in which laser light is irradiated to a semiconductor thin film, a refractive index of the semiconductor thin film after laser light irradiation is measured and conditions for the next laser light irradiation are adjusted based on the measured refractive index value. For example, laser light irradiation conditions are adjusted so that semiconductor thin films always have the same refractive index. As a result, the annealing can be performed under the same conditions at every laser light irradiation even if the laser light irradiation conditions vary unavoidably.

Abstract: A method for growing an epitaxial silicon-germanium layer is described. The method includes removing a native oxide layer on the silicon substrate surface. A HF vapor treatment process is then conducted on the silicon substrate. Thereafter, a germanium layer is formed on the silicon substrate, followed by performing a rapid thermal anneal process under an inert gas to form a silicon-germanium alloy layer on the surface of the silicon substrate.

Abstract: Si nanocrystals are formed by irradiating SiO2 substrates with electron beams at a temperature of 400° C. or higher, thereby causing electron-stimulated decomposition reaction. As a result of the said reaction, single crystalline Si nanostructures are fabricated on the SiO2 substrate with good size and positional controllability.

Abstract: In an annealing process in which laser light is irradiated to a semiconductor thin film, a refractive index of the semiconductor thin film after laser light irradiation is measured and conditions for the next laser light irradiation are adjusted based on the measured refractive index value. For example, laser light irradiation conditions are adjusted so that semiconductor thin films always have the same refractive index. As a result, the annealing can be performed under the same conditions at every laser light irradiation even if the laser light irradiation conditions vary unavoidably.

Abstract: A polycrystalline article is converted to a single crystal in a solid-state process. Heat is applied at a first end of the article to effect a predetermined spatial temperature profile thereat having a maximum temperature approaching a melting temperature thereof. The temperature profile is maintained to initiate conversion at the first end. The heat is moved along the article toward an opposite second end to correspondingly propagate the conversion along the article.

Abstract: A method for producing a silicon ingot having a directional solidification structure comprising the steps of: placing a silicon raw material into a crucible of a melting device constructed by mounting a chill plate on an underfloor heater, mounting a crucible with a large cross-sectional area on the chill plate, providing an overhead heater over the crucible, and surrounding the circumference of the crucible with a heat insulator; heat-melting the silicon raw material by flowing an electric current through the underfloor heater and overhead heater; chilling the bottom of the crucible by halting the electric current through the underfloor heater after the silicon raw material has been completely melted to form a molten silicon; chilling the bottom of the crucible by flowing an inert gas through the chill plate; and intermittently or continuously lowering the temperature of the overhead heater by intermittently or continuously decreasing the electric current through the overhead heater, and an apparatus for pro

Abstract: The method for making a uniform, large-size single crystal of calcium fluoride includes placing a single precursor crystal of calcium fluoride in a tempering vessel provided with a cover; introducing calcium fluoride powder into the tempering vessel and subsequently heating the single precursor crystal, preferably in intimate contact with the calcium fluoride powder, in the tempering vessel together with the calcium fluoride powder for two or more hours at temperatures above 1150° C. to temper the precursor crystal and thus form the uniform, large-scale single crystal of calcium fluoride. The uniform large-sized single crystals of calcium fluoride can be used to make improved lens, prism, light-conducting rod, optical window or other optical component for DUV photolithography, steppers, excimer lasers, wafers, computer chips and electronic devices containing the wafers and chips.

Abstract: In growing silicon single crystals by the CZ method, the cooling rate in the 1150-1080° C. temperature zone (defect-forming temperature range) where the grown-in defects are formed is set at more than 2.0° C./min to manufacture single crystals having an as-grown LSTD density of larger than 3.0×106/cm3 or a FPD density of larger than 6.0×105/cm3. As this single crystal has a small defect size, thus the dissolution rate of the defects increases by the heat treatment in a non-oxidizing atmosphere containing a hydrogen gas, so the effect of the hydrogen heat treatment can extend to the depth more than 3 &mgr;m from the wafer surface.

Abstract: Planarizing High Temperature Superconductor (HTS) surfaces, especially HTS thin film surfaces is crucial for HTS thin film device processing. Disclosed is a method of surface planarization for HTS film. The method includes first smoothing the HTS surface by Gas Cluster Ion Beam bombardment, followed by annealing in partial pressure of oxygen to regrow the damaged surface layer. A rough HTS surface can be planarized down to a smoothness with a standard deviation of one nanometer or better.

Abstract: According to the present invention, a complex (M) which is formed by growing a polycrystalline &bgr;-SiC plate 2 having a thickness of 10 &mgr;m or more on the surface of a single crystal &agr;-SiC base material 1 by the PVD method or the thermal CVD method is heat-treated at a temperature of the range of 1,650 to 2,400° C., whereby polycrystals of the polycrystalline cubic &bgr;-SiC plate 2 are transformed into a single crystal, and the single crystal oriented in the same direction as the crystal axis of the single crystal &agr;-SiC base material 1 is grown. As a result, single crystal SiC of high quality which is substantially free from micropipe defects and defects affected by the micropipe defects can be produced easily and efficiently.

Abstract: A method of making an electronic device, according to an exemplary embodiment of the invention, comprises the steps of: forming a polycrystalline substrate in a desired shape; converting the polycrystalline substrate into a single crystal substrate using a solid state crystal conversion process; and forming an electronic element on the substrate. Typically, alumina is formed in the shape of a wafer, sintered to form a densified polycrystalline alumina wafer, and heated to a temperature between the melting point of alumina and one-half the melting point of alumina to convert the densified polycrystalline alumina wafer into a sapphire wafer. A light-emitting diode or other electronic device, such as a laser diode, a high frequency microwave device, or an optoelectronic detector, can be formed on the wafer by depositing layers of semiconductor material on the wafer. The solid state crystal conversion process provides several advantages in forming electronic devices.

Abstract: The single crystal SiC according to the present invention is produced in the following manner. Two complexes M in each of which a polycrystalline film 2 of &bgr;-SiC (or &agr;-SiC) is grown on the surface of a single crystal &agr;-SiC substrate 1 by thermochemical deposition, and the surface 2a of the polycrystalline film 2 is ground so that the smoothness has a surface roughness of 200 angstroms RMS or smaller, preferably 100 to 50 angstroms RMS are subjected to a heat treatment under a state where the complexes are closely fixed to each other via their ground surfaces 2a′, at a temperature of 2,000° C. or higher and in an atmosphere of a saturated SiC vapor pressure, whereby the polycrystalline films 2 of the complexes M are recrystallized to grow a single crystal which is integrated with the single crystal &agr;-SiC substrates 1. Large-size single crystal SiC in which impurities, micropipe defects, and the like do not remain, and which has high quality can be produced with high productivity.

Abstract: A method for forming an optical device includes the steps of providing a first plate having a first face defining a recess, filling the recess with a material which can be crystallized, and covering the first face and the recess with a second plate having a second face, so that the second face is in contact with the first face and the material in the recess is completely enclosed by the first and second plates. The material in the recess is thereby protected from chemical and mechanical damage, as well as evaporation. In addition, the plates can be transparent, allowing the material in the recess to be visually monitored. A grown crystalline film packed in the cell can be used as a non-liner and/or electro-optical device.

Abstract: A method of bonding a particle material to near theoretical density, includes placing a particle material in a die. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps. is applied. The method can be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material. The method may also be applied to perform combustion synthesis of a reactive material, followed by consolidation or joining to near-net shaped articles or parts.

Abstract: In single crystal SiC according to the present invention, a single crystal &agr;-SiC substrate and a polycrystalline &bgr;-SiC plate are laminated to each other for fixation, the single crystal &agr;-Sic substrate and the polycrystalline &bgr;-SiC plate are subjected to heat treatment under an inert gas atmosphere and a saturated SiC vapor atmosphere, whereby the single crystallization owing to solid-phase transformation of the polycrystalline &bgr;-SiC plate and a progress of the single crystallization to a surface direction wherein a contact point is regarded as a starting point make a whole surface of layer of the polycrystalline &bgr;-SiC plate grow efficiently into a single crystal integrated with the single crystal &agr;-SiC substrate, whereby it is possible to produce single crystal SiC having high quality with high productivity, which is substantially free from lattice defects and micropipe defects.

Abstract: A process for producing .alpha.-alumina powder comprising the step of calcining at least one of transition alumina and a transition alumina precursor capable of becoming transition alumina on heating, in a gas atmosphere containing (1) a hydrogen halide, (2) a component prepared from a halogen and steam or (3) a halogen, in the presence of at least one of a seed crystal and a shape-controlling agent. The .alpha.-alumina powder is particularly useful as a raw material for abrasives, fillers, sinters or spacers which comprises .alpha.-alumina particles having a substantially octahedral or eicosahedral shape, a specific structure, and a narrow primary particle size distribution.

Abstract: According to the present invention, a complex (M) which is formed by stacking a polycrystalline .beta.-SiC plate 2 on the surface of a single crystal .alpha.-SiC base material 1 in a close contact state via a polished face or grown in a layer-like manner by the thermal CVD method is heat-treated in a temperature range of 1,850 to 2,400.degree. C., whereby polycrystals of the polycrystalline cubic .beta.-Sic plate are transformed into a single crystal, and the single crystal oriented in the same direction as the crystal axis of the single crystal .alpha.-SiC base material is grown. As a result, large single crystal SiC of high quality which is free from micropipe defects, lattice defects, generation of grain boundaries due to intrusion of impurities, and the like can be produced easily and efficiently.

Abstract: According to the present invention, a complex (M) which is formed by growing a polycrystalline .beta.-SiC plate 2 on the surface of a single crystal .alpha.-SiC base material 1 by the thermal CVD method is heat-treated at a high temperature of 1,900 to 2,400.degree. C., whereby polycrystals of the polycrystalline cubic .beta.-SiC plate are transformed into a single crystal, so that the single crystal is oriented in the same direction as the crystal axis of the single crystal .alpha.-SiC base material and integrated with the single crystal of the single crystal .alpha.-SiC base material to be largely grown. As a result, single crystal SiC of high quality which has a very reduced number of lattice defects and micropipe defects can be efficiently produced while ensuring a sufficient size in terms of area.

Abstract: A process is disclosed for reducing the crystallization temperature of amorphous or partially crystallized ceramic films by providing a higher pressure under which the crystallization of the amorphous or partially crystallized ceramic films can be significantly enhanced. The present invention not only improves quality, performance and reliability of the ceramic films, but also reduces the cost for production. By lowering the crystallization temperature, the cost for thermal energy consumed during the crystallization process is greatly reduced. In addition, the interaction or interdiffusion occurring between films and substrates is significantly suppressed or essentially prevented, avoiding the off-stoichiometry and malfunction of thin films, which usually occur in the conventional high-temperature crystallization processes. The process of present invention also decreases the grain size of formed films, thus reducing the roughness of films and producing relatively smooth, good quality films.

Abstract: A complex (M) which is formed by growing a polycrystalline .beta.-SiC plate 4 by the thermal CVD method on crystal orientation faces which are unified in one direction of plural plate-like single crystal .alpha.-SiC pieces 2 that are stacked and closely contacted is subjected to a heat treatment at a temperature in the range of 1,850 to 2,400.degree. C., whereby a single crystal which is oriented in the same direction as the crystal axes of the single crystal .alpha.-SiC pieces 2 is grown from the crystal orientation faces of the single crystal .alpha.-SiC pieces toward the polycrystalline .beta.-SiC plate 4. As a result, single crystal SiC of a high quality in which crystalline nuclei, impurities, micropipe defects, and the like are not substantially generated in an interface can be produced easily and efficiently.

Abstract: A polycrystalline carbon body is converted to a different crystallography by directing an infrared laser beam at a crystal boundary interface. By using a beam having a 5.3 micron wavelength so as to fall within a 5-9 micron range of normal spectral transmittance of the carbon, the interface is heated for solid state conversion by passing the beam through a forward portion of the body without appreciably heating the forward portion. During heating, the interface propagates through the body, thus converting an ever-decreasing aft portion of the body to the different crystallography.

Abstract: A colloidal suspension comprising metal chalcogenide nanoparticles and a volatile capping agent. The colloidal suspension is made by reacting a metal salt with a chalcogenide salt in an organic solvent to precipitate a metal chalcogenide, recovering the metal chalcogenide, and admixing the metal chalcogenide with a volatile capping agent. The colloidal suspension is spray deposited onto a substrate to produce a semiconductor precursor film which is substantially free of impurities.

Abstract: A process for fabricating a semiconductor by crystallizing a silicon film in a substantially amorphous state by annealing it at a temperature not higher than the crystallization temperature of amorphous silicon, and it comprises forming selectively, on the surface or under an amorphous silicon film, a coating, particles, clusters, and the like containing nickel, iron, cobalt, platinum or palladium either as a pure metal or a compound thereof such as a silicide, a salt, and the like, shaped into island-like portions, linear portions, stripes, or dots; and then annealing the resulting structure at a temperature lower than the crystallization temperature of an amorphous silicon by 20 to 150.degree. C.

Abstract: A method for solid state formation of diamond includes providing a diamond growth substrate, such as single-crystal silicon, forming on the diamond growth substrate an alloy of carbon and a metal which permits carbon to exist in a matrix therein, and causing carbon atoms from the alloy to precipitate on the diamond growth substrate in a diamond cubic lattice. The alloy may be an alloy of aluminum and carbon. The alloy is annealed in a hydrogen ambient to cause diffusion of hydrogen through the alloy to the surface of the substrate, providing a high concentration of hydrogen at the interface between the substrate and the alloy. The alloy is heated to cause carbon atoms in the alloy to diffuse through the alloy to the interface and form diamond.

Abstract: After a pattern is transferred on silicon film crystallized by annealing, the silicon film is annealed by radiation of intense rays for a short time. Especially, in the crystallizing process by annealing, an element which promotes crystallization such as nickel is doped therein. The area not crystallized by annealing is also crystallized by radiation of intense rays and a condensed silicon film is formed.After a metal element which promotes crystallization is doped, annealing by light for a short time is performed by radiating intense rays onto the silicon film crystallized by annealing in an atmosphere containing halide. After the surface of the silicon film is oxidized by heating or by radiating intense rays in a halogenated atmosphere and an oxide film is formed on the silicon film, the oxide film is then etched. As a result, nickel in the silicon film is removed.

Abstract: In an annealing process in which laser light is irradiated to a semiconductor thin film, a refractive index of the semiconductor thin film after laser light irradiation is measured and conditions for the next laser light irradiation are adjusted based on the measured refractive index value. For example, laser light irradiation conditions are adjusted so that semiconductor thin films always have the same refractive index. As a result, the annealing can be performed under the same conditions at every laser light irradiation even if the laser light irradiation conditions vary unavoidably. For a crystalline silicon film, if the refractive index is larger than 3.5, then a thin-film transistor using such as film has desired crystallinity and flatness properties such that a field-effect mobility is greater than 100 cm.sup.2 /Vsec.

Abstract: The surface 1a of a single crystal .alpha.-SiC substrate 1 is adjusted so as to have a surface roughness equal to or lower than 2,000 angstroms RMS, and preferably equal to or lower than 1,000 angstroms RMS. On the surface 1a of the single crystal .alpha.-SiC substrate 1, a polycrystalline .alpha.-SiC film 2 is grown by thermal CVD to form a complex is placed in a porous carbon container and the carbon container is covered with .alpha.-SiC powder. The complex is subjected to a heat treatment at a temperature equal to or higher than a film growing temperature, i.e., in the range of 1,900 to 2,400.degree. C. in an argon gas flow, whereby single crystal .alpha.-SiC is integrally grown on the single crystal .alpha.-SiC substrate 1 by crystal growth and recrystallization of the polycrystalline .alpha.-SiC film 2. It is possible to stably and efficiently produce single crystal SiC of a large size which has a high quality and in which any crystal nucleus is not generated.

Abstract: A method is disclosed for forming a single crystal relaxor based material, including the following steps: providing a seed single crystal plate, providing a first and second polycrystalline structure, bonding the top surface of the seed crystal plate to the outer surface of the first polycrystalline structure, bonding the bottom surface of the seed crystal plate to the outer surface of the second polycrystalline structure, and annealing the bonded structure.

Abstract: A method is provided for preparing, with high reproducibility, a carbon-doped group III-V compound semiconductor crystal having favorable electrical characteristics and having impurities removed therefrom, and in which the amount of doped carbon can be adjusted easily during crystal growth. This method includes the steps of: filling a crucible with compound raw material, solid carbon, and boron oxide; sealing the filled crucible gas impermeable material; heating and melting the compound raw material under the sealed state in the airtight vessel; and solidifying the melted compound raw material to grow a carbon-doped compound semiconductor crystal.

Abstract: In order to form a single-crystalline thin film on a polycrystalline substrate using plasma CVD, a downwardly directed mainly neutral Ne atom current is formed by an ECR ion generator (2). A reaction gas such as silane gas which is supplied from a reaction gas inlet pipe (13) is sprayed onto an SiO.sub.2 substrate (11) by an action of the Ne atom current, so that an amorphous Si thin film is grown on the substrate (11) by a plasma CVD reaction. At the same time, a part of the Ne atom current having high directivity is directly incident upon the substrate (11), while another part thereof is incident upon the substrate (11) after its course is bent by a reflector (12). The reflector (12) is so set that all directions of the parts of the Ne atom current which are incident upon the substrate (11) are perpendicular to densest planes of single-crystalline Si.

Abstract: A method for forming a silicon island used for forming a TFT or thin film diode comprises the step of pattering a silicon film with a photoresist mask. In order to prevent the contamination of the semiconductor film due to the photoresist material, a protective film such as silicon oxide is interposed between the semiconductor film and the photoresist film. Also, the protective film is preferably formed by thermal annealing or light annealing in an oxidizing atmosphere.

Abstract: A method of fabricating a stacked type capacitor. A semiconductor substrate having a transistor, a field oxide layer, and a conductive layer formed on top of the field oxide layer is provided. The transistor comprises a gate and a source/drain region. A first dielectric layer is formed over the substrate. An oxide layer is formed over the first dielectric layer. A second dielectric layer is formed on the oxide layer. An etching step is performed to the second dielectric layer to form an opening therein. A first poly-silicon layer is formed on the second dielectric layer and the opening. The first poly-silicon layer is etched back to remove a part of the first poly-silicon layer. A first spacer is formed on a wall of the opening. The oxide layer is etched for a first height by using the first spacer and the second dielectric layer as a first mask. A second poly-silicon layer is formed on the second dielectric layer and the opening.

Abstract: Provided are high-purity quartz glass having a high purity, in particular, with little zirconium (Zr) and manufactured at low costs from natural quartz as the starting material and a method for the preparation thereof.

Abstract: Secondary recrystallized grains having a plurality of crystal orientations in a polycrystalline compact of molybdenum or tungsten, which contains at least one element selected from the group consisting of calcium and magnesium in amount of 0.007 to 0.090 atom %, are formed by locally heating an end portion(s) of the polycrystalline compact. Some grains, which have a prescribed crystal orientation, selected from these secondary recrystallized grains are subsequently grown in the whole polycrystalline compact by annealing.

Abstract: A heat treating method in which the ultimate temperature of semiconductor single crystal substrates being heat treated is made constant. The method includes heating at least the back surface of the substrate directly with radiant heat. The heating output is controlled according to the reflectivity of the back surfaces of the semiconductor single crystal substrates. In particular, the heating output is increased or decreased in proportion to the increase or decrease in the reflectivity of the back surface of the substrates from one substrate to the next. The method makes its possible to keep a uniform crystal quality throughout the heat treated semiconductor single crystal substrates.

Abstract: Diamond materials are formed by sandwiching a carbon-containing material in a gap between two electrodes. A high-amperage electric current is applied between the two electrode plates so as cause rapid-heating of the carbon-containing material. The current is sufficient to cause heating of the carbon-containing material at a rate of at least approximately 5,000.degree. C./sec, and need only be applied for a fraction of a second to elevate the temperature of the carbon-containing material at least approximately 1000.degree. C. Upon terminating the current, the carbon-containing material is subjected to rapid-quenching (cooling). This may take the form of placing one or more of the electrodes in contact with a heat sink, such as a large steel table. The carbon-containing material may be rapidly-heated and rapidly-quenched (RHRQ) repeatedly (e.g., in cycles), until a diamond material is fabricated from the carbon-containing material.

Abstract: A radio frequency automatic identification system detects targets which include solid resonators resonating at several frequencies, attributing information to the frequencies at which the target resonates. Preferred resonators are quartz crystals, which may be made by a process of heating quartz to soften it and cutting crystals to approximate size and resonant frequency. Resonators produced by such a process are measured to determine their actual resonant frequency, and preferably the crystals are sorted into predetermined frequency windows in accordance with their measured resonant frequency. A set of resonators having frequencies corresponding to predetermined data is selected from the sorted groups of resonators and incorporated into a target. The preferred target is an ink-like material having a plurality of resonators disposed in a matrix which is radio frequency transparent at the frequency of interest.

Abstract: The invention concerns a method of producing a surface layer structure by doping a matrix with metal ions. The aim of the invention is to provide a method of this kind in which the depth distribution of the metal ions in the substrate can be regulated, thus optimumizing the doping without incurring any of the disadvantages inherent in the prior art methods. This is achieved by first depositing matrix material on a suitable substrate by laser ablation in an atmosphere of oxygen, thus forming a on surface of the substrate a first layer a matrix material. Dopant is then deposited on the surface of the first layer, followed by more matrix material. The result is a uniform doping of the deposited matrix at a defined depth in the surface layer structure.

Abstract: A single crystal material is prepared by forming a layer of an amorphous substance over a surface of a substrate of a single crystal having the same chemical composition as that of the amorphous substance, the resulting composite material is heated to epitaxially grow the amorphous layer into a single crystal layer. A composite material for producing such a single crystal material is also disclosed which includes a substrate of a single crystal, and a layer of an amorphous substance having the same chemical composition as that of the substrate, the layer having such a thickness that the layer as a whole can epitaxially grow to make a single crystal layer.