Abstract: The present invention is directed to the technical field of the manufacture of calcium fluoride single crystals by growing from a melt by the directed crystallization and by using a seed crystal, such crystals having high optical homogeneity and small birefringence. The method includes crystallization from a melt and an annealing of crystals with the subsequent cooling in the vacuum furnace by continuous transfer of the crucible containing a melt from a melt zone into the annealing zone at independent regulation of modes of both zones in which the cooling of crystals in the range 1100-700° C. is carried out with a rate of 1.3-2.0° C./hr, a constant axial temperature drop with a gradient 20-50° C./m at is provided in the absence (or minimum) radial gradient, and this is provided by moving downwards a water-cooled rod moving at a speed of 0.8-1.4 of the speed of the crystal movement, the water-cooled rod being arranged towards a crucible bottom at a distance equal to 0.3-0.

Abstract: The present application discloses a method for preparing a homogeneous ternary or quaternary alloy from a quaternary melt. The method includes providing a family of phase diagrams for the quaternary melt which shows (i) composition/temperature data, (ii) tie lines connecting equilibrium liquid and solid compositions, and (iii) isotherms representing boundaries of a miscibility gap. Based on the family of phase diagrams, a quaternary melt composition and an alloy growth temperature is selected. A quaternary melt having the selected quaternary melt composition is provided and a ternary or quaternary alloy is grown from the quaternary melt at the selected alloy growth temperature. A method for making homogeneous ternary or quaternary alloy from a ternary or quaternary melt is also disclosed, as are homogeneous quaternary single-crystal alloys which are substantially free from crystal defects and which have the formula AxB1−xCyD1−y, x and y being the same or different and in the range of 0.001 to 0.

Abstract: A crucible having an inner surface is not wetted by a melt which shrinks when it solidifies is provided with indentations in the walls of the crucible to support an ingot grown in it. Supporting the crystal provides a gap between the bottom of the ingot and the inner surface of the bottom of the crucible. The gap allows more uniform heat transfer from the bottom of the crucible than is provided when there is no gap; the gap provides a controllable temperature gradient between the interior and exterior of the crucible. To direct propagation of the growth of a macrocrystal the bottom of the crucible is provided with at least one set of multiple grooves in parallel relationship with each other. Preferably a second set of multiple grooves in parallel relationship with each other intersect the grooves of the first set at an angle chosen depending upon the lattice structure of the macrocrystal to be grown. A macrocrystal grown in a crucible with twin sets of angulated grooves produces single crystals.

Abstract: A method for manufacturing a solid single crystal of an electrically conductive material by pulling from a molten mass of this material, the material presenting atom clusters at melt. The method includes: a melt stage so as to obtain a molten mass, the melt stage procuring a colder zone of the molten mass, from which the single crystal will be pulled, and a hotter zone having sufficient temperature to melt the atom clusters; a stage of application to the molten mass of a rotating magnetic field allowing the atom clusters to be displaced from the colder zone to the hotter zone; and a stage of growth by pulling of the single crystal after the atom clusters have been displaced from the colder zone to the hotter zone.

Abstract: In order to provide a fluoride refining method and a fluoride crystal manufacturing method that have great general-purpose properties and can reduce the manufacturing cost and to provide at a low cost a fluoride crystal, an optical part and an aligner the transmission characteristics of which are hardly degraded even when repeatedly irradiated with a high-output light of a short wavelength for a long term, there is provided a method of refining a fluoride comprising the heating step of heating a solid scavenger-added fluoride raw material to melt the raw material and the cooling step of cooling the molten fluoride material to solidify the melt, wherein the environment of a chamber housing the fluoride raw material is changed to such an environment that a gas in the chamber is discharged to the outside of the chamber more easily than the environment before the change, during the heating step.

Abstract: A crucible having an inner surface which is not wetted by a melt which shrinks when it solidifies, is provided with indentations in its walls, the indentatons located remote from its rim. The indentations are located beneath a lateral plane through the walls of the crucible, at about two-thirds (66.6%) of the vertical height of the walls, measured from the floor of the crucible, support an ingot grown in it. Supporting the crystal provides a gap between the bottom of the ingot and the inner surface of the bottom of the crucible. The gap allows more uniform heat transfer from the bottom of the crucible than is provided when there is no gap; the gap provides a controllable temperature gradient between the interior and exterior of the crucible. To direct propagation of the growth of a macrocrystal, the bottom of the crucible is provided with at least one set of multiple grooves in parallel relationship with each other.

Abstract: A method and apparatus for producing crystals that minimizes birefringence even at large crystal sizes, and is suitable for production of CaF2 crystals. The method of the present invention comprises annealing a crystal by maintaining a minimal temperature gradient in the crystal while slowly reducing the bulk temperature of the crystal. An apparatus according to the present invention includes a thermal control system added to a crystal growth and annealing apparatus, wherein the thermal control system allows a temperature gradient during crystal growth but minimizes the temperature gradient during crystal annealing.

Abstract: An amorphous film 2 is formed on a single crystalline substrate 1. Then, the amorphous film is selectively removed by photolithography to form windows 3. Subsequently, the windows 3 are contacted with a supersaturated solution 5 dissolving a given element in supersaturation and thereby, single crystals containing the given element as a constituting element are epitaxially grown in a perpendicular direction to a surface of the single crystalline substrate from the windows. Then, after a given time elapsed, the epitaxial growth is stopped by finishing the contact of the windows with the supersaturated solution 5 and single crystalline members 6 having given sizes and shapes are obtained.

Abstract: The invention concerns a method for manufacturing a solid single crystal of a material which is electrically conductive in the molten state, by pulling from a molten mass of this material, the material presenting atom clusters at melt, the method including:

Abstract: Disclosed are a P-type GaAs single crystal having an average dislocation density of 500 cm−2 or lower, and a manufacturing method therefor. The P-type GaAs single crystal is characterized by containing, as dopants, Si at an atomic concentration of from 1×1017 to 1×1019 cm−3 and Zn at an atomic concentration of from 2×1018 to 6×1019 cm−3. Further, as another example, B is contained at an atomic concentration of from 1×1017 to 1×1020 cm−3.

Abstract: An object of the present invention is to reduce the etch pit density (EPD) and the full-width-half-maximum (FWHM) value of the double crystal X-ray rocking curve, and to provide a CdTe crystal or a CdZnTe crystal which does not include deposits having Cd or Te and the process for producing the same. After a CdTe crystal or a CdZnTe crystal was grown, while the temperature of the crystal is from 700 to 1050° C., the Cd pressure is adjusted so as to keep the stoichiometry of the crystal at the above temperature. The crystal is left for time t which is determined so that each of a diameter L(r) of the crystal and a length L(z) thereof satisfies the following equation 1: {L(r),(L(z))}/2<{4exp(−1.15/kT)×t}½. Then, when the crystal is cooled, the temperature of the crystal is decreased within a range in which the temperature of the crystal and that of a Cd reservoir satisfy the following equation 2: −288+1.68×TCd<TCdTe<402+0.76×TCd.

Abstract: An object of the present invention is to provide a fluoride crystal having a high transmittance with respect to an excimer laser and an excellent resistance with respect to a high output laser, and a production method therefore. The fluoride crystal of the present invention contains at least one kind of atom selected from the group consisting of Zn, Cd, Pb, Li, Bi and Na with a content of 10 ppm or less, and has an internal transmittance of 70% or more with respect to 135 nm wavelength light. The method of the present invention of producing a fluoride crystal comprises conducting a refining step of adding a scavenger to a calcium fluoride raw material and refining the raw material at least once, and a crystal growth step of further adding the scavenger to the refined raw material and growing a crystal by using a crucible lowering method, wherein the amount of the scavenger to be added in the first refining step is 0.04 to 0.

Abstract: The present invention provides a raw material for manufacturing an inexpensive fluoride crystal with excellent optical characteristics, and a method of manufacturing a fluoride crystal using a carbon fluoride-based gas that can easily be handled and is capable of preventing gases from being taken into a crystal to avoid degradation of transmittance, etc., and provides further a fluoride crystal and a manufacturing method thereof.

Abstract: In the process of thin film growth, actual temperature of a substrate is measured and corrected with low cost in short time. With first thin film growth equipment of which a difference between set temperature of a heating source and an actual temperature of the substrate (hereinafter, referred to as temperature characteristic) is known, a first calibration curve representing “thin film growth rate vs. substrate actual temperature” is prepared. Next, thin film growth is conducted at one set temperature T2 with use of second thin film growth equipment whose temperature characteristic is unknown, where a difference from a set temperature T1 reading from the first calibration curve in correspondence to a thin film growth rate G resulting from the thin film growth process is determined.

Abstract: A manufacturing method for a single crystal of calcium fluoride includes the steps of degassing calcium fluoride powder particles to desorb impurities from surfaces of the calcium fluoride powder particles, preprocessing the degassed calcium fluoride powder particles by fusing the degassed calcium fluoride powder particles in a crucible to obtain a preprocessed product, and re-fusing the preprocessed product in a crucible to grow a single crystal of calcium fluoride.

Abstract: A liquid raw material is heated to its boiling point or higher at a vaporizer to mix the vaporized ingredient gas and a carrier gas at a mixer at predetermined concentrations. The flow of the mixed gas is adjusted while the mixed gas is heated to over its condensing point and the temperature thereof is kept. Subsequently, the mixed gas is fed to a reactor for epitaxial growth while the mixed gas is heated to over its condensing point and the temperature thereof is kept. When the temperature of a heating medium is kept constant at the vaporizer to vaporize the liquid raw material and the feeding amount of the liquid into the vaporizer is adjusted by the pressure of the gas inside the vaporizer, the liquid surface level can be controlled to be constant.

Abstract: A composition of matter comprising a bulk material of uniform composition having first and second spaced apart surface regions and a dopant in the bulk material of progressively increasing concentration in a direction from the first to said second surface regions providing an interface intermediate the first and second surface regions wherein the portion of the bulk material on one side of the interface is electrically conductive and the portion of the bulk material on the other side of the interface is relatively electrically insulative. The bulk material is one of Ge, Si, group II-VI compounds and group III-V compounds and preferably GaAs or GaP. The dopant is a shallow donor for the bulk material involved and for GaAs and GaP is Se, Te or S. The ratio of the resistivity of the portion of the bulk material on one side of the interface to the portion of the bulk material on the other side of the interface is at least about 1:10.sup.7.

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: Disclosed is a levitation melting method comprising applying a high-frequency current to a high frequency induction coil wound around a melting crucible to induction-heat a material introduced to the melting crucible; and erecting the resulting molten metal to be in no contact with the inner wall surface of the melting crucible with the bottom of the material being maintained in the solidified state; wherein a power input P of a high-frequency power source to the high-frequency induction coil, an inner radius R at the bottom of the crucible and super heat .DELTA.T of the molten metal satisfy the relationship of P/R2=.DELTA.T.multidot.(0.0008 to 0.002), as well as, a melting and casting method for casting the molten metal prepared by the levitation melting method described above into a mold using a snout suspended above the melting crucible such that the lower end of the snout may be submerged in the molten metal.

Abstract: A temperature measurement system for use in a thin film deposition system is based on optical pyrometry on the backside of the deposition substrate. The backside of the deposition substrate is viewed through a channel formed in the susceptor of the deposition system. Radiation from the backside of the deposition substrate passes through an infrared window and to an infrared detector. The signal output by the infrared detector is coupled to electronics for calculating the temperature of the deposition substrate in accordance with blackbody radiation equations. A tube-like lightguide shields the infrared detector from background radiation produced by the heated susceptor.

Abstract: An improved plasma enhanced chemical vapor deposition (CVD) reactor is provided for the synthesis of diamond and other high temperature materials such as boron nitride, boron carbide and ceramics containing oxides, nitrides, carbides and borides, or the like. An aspect of the present method enables a plasma to substrate distance to be optimized for a given surface. This has been found to enable a substantially uniform thin film coating of diamond or like material to be deposited over a substrate.

Abstract: An optical dome or window formed of a composition which is transmissive to infrared frequencies in the range of from about 1 micron to about 14 microns and which is relatively opaque to substantially all frequencies above about 14 microns consisting essentially of a compound taken from the class consisting of group III-V compounds doped with an element taken from the class consisting of shallow donors and having less than about 1.times.10.sup.7 atoms/cc impurities and having less than about 1.times.10.sup.15 parts carbon. The shallow donors are Se, Te and S, preferably Se, with the Se concentration from 5.times.10.sup.15 atoms/cc to 2.times.10.sup.16 atoms/cc. The group III-V compound is preferably GaAs or GaP.

Abstract: The present invention is an apparatus for the synthesis and growth of single crystals of phosphorus compounds starting with the elemental materials in a single furnace without external exposure. The apparatus of the present invention is a crystal growth furnace heated by RF coils. Inside the furnace is a susceptor heated by a lower coil device for holding a crucible. Above the crucible is selectively positioned a phosphorus improved injector. The improved injector is further surrounded by a susceptor which is heated by an upper coil device. The non-phosphorus materials are placed in the crucible and melted to a desired temperature. The phosphorus material previously placed within the injector is heated by the radiant heat from both crucible and the upper susceptor to drive the phosphorus vapor into the melt through a tube. This is closely controlled by noting the temperature within the injector and adjusting the height of the injector above the melt to control the temperature within the phosphorus material.

Abstract: Growth of homogeneous single crystals is carried out by a modified Bridgman-type process using a second melt of a different composition to replenish the first melt of a predetermined composition held in the crystal growth container. By controlling the replenishing rate and suppressing diffusion between the two melts, composition variations in the first melt and hence the growing crystal are compensated. The second melt may be maintained at a predetermined higher temperature than the first melt. The first melt may be agitated during crystal growth by rotation. A liquid encapsulant may be used.

Abstract: The present invention is a process and apparatus for the synthesis and growth of single crystals of phosphorus compounds starting with the elemental materials in a single furnace without external exposure. The apparatus of the present invention is a crystal growth furnace heated by RF coils. Inside the furnace is a susceptor for holding a crucible. Above the crucible is selectively positioned a phosphorus improved injector. The non-phosphorus materials are placed in the crucible and melted to a desired temperature. The phosphorus material previously placed within the injector is heated by the radiant heat from the crucible to drive the phosphorus vapor into the melt through a tube. This is closely controlled by noting the temperature within the injector and adjusting the height of the injector above the melt to control the temperature within the phosphorus material. After the formation of the stoichiometric melt, the seed is inserted into the melt for crystal growth if so desired.