Abstract: The present disclosure describes a scintillation crystal having the general formula RE(1?y)MyF3XA3(1?x), wherein RE includes; A is selected from Cl, Br or I; and M is an activator ion selected from the Ce3+, Pr3+ or Eu3+; x is greater than 0.01 mole% and strictly less than 100 mole%, and y is greater than 0.01 mole% and strictly less than 100 mole%; and wherein the at least one activator ion is further combined with ions from the group of Ho3+, Er3+, Tm3+, or Yb3+.

Abstract: A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa1-yEuyI3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA1-yEuyX3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0?y?1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

Abstract: A garnet-type single crystal is represented by a general formula, A3B2C3O12 (having a crystal structure with three sites A, B and C occupied by cations, wherein A represents an element occupying the site A, B represents an element occupying the site B, C represents an element occupying the site C, O represents an oxygen atom), and contains fluorine, in which the fluorine attains any one or both of substituting for the oxygen atom or compensating for oxygen defect.

Abstract: A fluorite having all the more excellent laser durability compared to a conventional fluorite is provided. A fluorite is proposed, in which the standard deviation of the surface areas of the Voronoi regions in a diagram from a Voronoi segmentation of the distribution of etch-pits in the (111) plane is 6,000 ?m2 or less, or, in which the standard deviation of the distances of the Delaunay edges in a diagram from a Delaunay segmentation of the distribution of etch-pits of the (111) plane is 80 ?m or less.

Abstract: The present invention provides for a composition comprising an inorganic scintillator comprising a lanthanide-doped strontium barium mixed halide useful for detecting nuclear material.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: The invention relates to nanostructure and its manufacturing method. In the manufacturing method of a nanostructure, first anisotropic crystalline particles, connectors having end to be connected to a specific crystal face of each of said crystalline particles, and second particles to be connected to the other end of each of said connectors are prepared. First ends of the connectors are connected to specific crystal faces of the first crystalline particles, and simultaneously or before or after the connection, the second ends of the connectors are connected to the second particles. A nanostructure formed by this method has a three-dimensional structure which does not have a closest packing structure.

Abstract: The inventive method for producing nanoparticles for ferrofluids by electron-beam evaporation and condensation in vacuum, consists in evaporating an initial solid material and in fixing nanoparticles to a cooled substrate by means of a solidifiable carrier during vapour condensation, wherein a solid inorganic material, which is selected from a group containing metals, alloys or oxides thereof, is used as an initial material and a solid liquid-soluble material is used as a magnetic carrier material for fixing nanoparticles. The method also consists in simultaneously evaporating the initial material and the carrier composition by electron-beam heating. The vapour is deposited on the substrate, the temperature which is lower than the melting point of the carrier material, and the condensate of the magnetic material nanoparticles, which have a size and are fixed in the carrier, is produced. The particle size is adjusted by setting the specified temperature of the substrate during vapour deposition.

Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.

Abstract: The invention provides compounds of, and methods for the preparation of compounds of, the molecular formula, SixGeyHz—aXa; wherein X is halogen, and x, y, z, and a are defined herein, and methods for the deposition of high-Ge content Si films on silicon substrates using compounds of the invention.

Abstract: The invention relates to a method of preparing a polycrystalline block of a halide of formula AeLnfX(3f+e) in which Ln represents one or more rare earths, X represents one or more halogen atoms selected from the group consisting of Cl, Br and I, and A represents one or more alkali metals selected from the group consisting of K, Li, Na, Rb and Cs, e, which may be zero, being less than or equal to 3f, and f being greater than or equal to 1, having a low water and oxyhalide content, in which the method comprises heating a mixture of, on the one hand, at least one compound having at least one Ln—X bond and, on the other hand, a sufficient amount of NH4X in order to obtain the oxyhalide content, resulting in a molten mass comprising the rare-earth halide, the heating being followed by cooling, and the heating, after having reached 300° C., never going below 200° C. before the molten mass has been obtained.

Abstract: A metal fluoride single crystal pulling apparatus that upward pulling initiation through termination, in the state of shallow melt capable of highly effective inhibition of scatterer formation, can perform stable growth of single crystal and can suppress any mixing of air bubbles and occurrence of crystal break during crystal growth, etc; and a process for producing a metal fluoride single crystal therewith. As a crucible for accommodating a melt of raw metal fluoride, use is made of a double structured crucible composed of an outer crucible and an inner crucible. In the upward pulling of single crystal, the accommodation depth of inner crucible relative to the outer crucible is increased in accordance with any decrease of melt accommodated in the inner crucible according to the growth of single crystal, so that the melt accommodated in the outer crucible is fed into the inner crucible to thereby maintain the amount of melt accommodated in the inner crucible within a given range.

Abstract: Homogeneity residuals of the refractive index have a strong influence on the performance of lithography tools for both 193 and 157 nm application wavelengths. By systematic investigations of various defects in the real structure of CaF2 crystals, the origin of homogeneity residuals can be shown. Based on a quantitative analysis we define limiting values for the individual defects which can be either tolerated or controlled by optimized process steps, e.g. annealing. These correlations were carried out for all three relevant main crystal lattice orientations of CaF2 blanks. In conclusion we achieved a strong improvement of the critical parameters of both refractive index homogeneity and striae for large size lens blanks up to 270 mm diameter.

Abstract: Inorganic scintillator material of formula AnLnpX(3p+n) in which has a very low nuclear background noise and is particularly suitable as a detector scintillator for coating weight or thickness measurements, in the fields of nuclear medicine, physics, chemistry and oil exploration, and for the detection of dangerous or illicit materials.

Abstract: A method for producing high-purity, large-volume monocrystals that are especially radiation-resistant and have low intrinsic birefringence. From a melt of crystalline raw material, with controlled cooling and solidification, a crystal is generated. As the crystalline raw material, shards and/or waste from already-grown crystals is used, and the re-used raw material 1) upon visual observation in daylight has no color; and 2) upon illumination with a white-light lamp in a darkroom a) has no or at maximum a just barely perceivable reddish and/or bluish fluorescence; and b) has no or at maximum a just barely perceivable diffuse scattering; and c) has no or only slight discrete scattering of at maximum two visually perceivable scattering centers per dm3. In this way, crystals can be obtained which after tempering have a BSDF value of <7×10?7, an RMS homogeneity after the subtraction of 36 Zernike coefficients of <15×10?8, an SDR-RMS value in the 111 direction of <0.2 nm/cm.

Abstract: The invention relates to nanostructure and its manufacturing method. In the manufacturing method of a nanostructure, first anisotropic crystalline particles, connectors having an end to be connected to a specific crystal face of each of said crystalline particles, and second particles to be connected to the other end of each of said connectors are prepared. First ends of the connectors are connected to specific crystal faces of the first crystalline particles, and simultaneously or before or after the connection, the second ends of the connectors are connected to the second particles. A nanostructure formed by this method has a three-dimensional structure which does not have a closest packing structure.

Abstract: A flux assisted solid phase epitaxy that can make a thin film having a crystalline perfection comparable with that of a bulk crystal and at a reduced cost is provided in which an amorphous film of a mixture of an objective substance to be grown epitaxially and a flux of a substance producing a eutectic with the objective substance but not producing any compound therewith is deposited on a substrate at a temperature less than a eutectic point of the substances, and the substrate is heat-treated at a temperature not less than the eutectic point of the objective and flux substances. A solid phase reaction, namely solid phase diffusion causes the objective and flux substances to be mixed together to form a liquid phase in their eutectic state from which the objective substance precipitates and epitaxially grows on the substrate.

Abstract: In a solid solution system of Al2O3 and CAO or SrO, it has been difficult to obtain a material having a high electrical conductivity (>10?4 S·cm?) at room temperature. A compound is provided in which electrons at a high concentration are introduced into a 12CaO.7Al2O3 compound, a 12SrO.7Al2O3 compound, or a mixed crystal compound containing 12CaO.7Al2O3 and 12SrO.7Al2O3. The compound formed by substituting all the free oxygen ions with electrons is regarded as an electride compound in which [Ca24Al28O64]4+(4e?) or [Sr24Al28O64]4+(4e?) serves as a cation and electrons serve as anions. When a single crystal or a hydrostatic pressure press molded material of a fine powder thereof is held at approximately 700° C. in an alkaline metal vapor or an alkaline earth metal vapor, melt of a hydrostatic pressure press molded material of a powder is held at approximately 1,600° C. in a carbon crucible, followed by slow cooling for solidification, or a thin film of the compound held at approximately 600° C.

Abstract: The present disclosure provides methods for forging cylindrical alkali halide melt-grown single-crystal-type ingots into rectangular blocks. The resulting rectangular blocks are devoid of peripheral cracks and fissures, and possess uniform properties and reduced levels of impurities.

Abstract: The method provides CaF2 single crystals with low scattering, small refractive index differences and few small angle grain boundaries, which can be tempered at elevated temperatures. In the method a CaF2 starting material is heat-treated for at least five hours at temperatures between 1000° C. and 1250° C. and then sublimed at a sublimation temperature of at least 1100° C. in a vacuum of at most 5*10?4 mbar to form a vapor. The vapor is condensed at a condensation temperature of at least 500° C., which is at least 20° C. below the sublimitation temperature, to form a condensate. Then a melt formed from the condensate is cooled in a controlled manner to obtain the single crystal, which is subsequently tempered. The method is preferably performed with a CaF2 starting material including waste material and cuttings from previously used melts.

Abstract: The present disclosure provides methods for forging cylindrical alkali halide melt-grown single-crystal-type ingots into rectangular blocks. The resulting rectangular blocks are devoid of peripheral cracks and fissures, and possess uniform properties and reduced levels of impurities.

Abstract: An improved technique that reduces the potential for trapped impurities and/or ensuring desired stoichiometry of a grown crystal. Improved contaminant removal is obtained by bubbling a scavenger gas, such as fluorine gas or hydrogen fluoride gas, through a melt of alkaline- or alkali-earth halides, to improve the purity of the melt by removing more volatile metal halides and oxygen contained within the melt. By reacting after the raw material has melted, any oxygen or metal impurities trapped in the raw material is free to react with the scavenger. A desired stoichiometry is achieved as the alkaline- or alkali-earth metals react with the halide in the scavenger gas. Decreasing the amount of impurities in the melt, and using a desired stoichiometeric melt, improves the radiation hardness and transmission properties of resulting ingot grown from the purified raw material. Additionally, this method may decrease the amount of time needed for outgassing.

Abstract: In a method of producing a lithium niobate substrate by the use of a lithium niobate crystal grown by the Czochralski process, the lithium niobate crystal is heat-treated at a temperature of from 300° C. or more to less than 500° C. in the state the lithium niobate crystal is buried in a powder constituted of at least one element selected from the group consisting of Al, Ti, Si, Ca, Mg and C, or in the state the lithium niobate crystal is held in a container constituted of at least one element selected from the group consisting of Al, Ti, Si, Ca, Mg and C.

Abstract: The invention is directed to a method for growing metal fluoride crystals suitable for use in below 200 nm optical lithography systems, the method comprising including at least the step of heating a crystal growth furnace to a temperature in the range of 1400-2000° C. to purify the furnace by removal of sulfur and chlorine prior to using the furnace for growing metal fluoride single crystals.

Abstract: Patterned zinc-oxide nanostructures are grown without using a metal catalyst by forming a seed layer of polycrystalline zinc oxide on a surface of a substrate. The seed layer can be formed by an atomic layer deposition technique. The seed layer is patterned, such as by etching, and growth of at least one zinc-oxide nanostructure is induced substantially over the patterned seed layer by, for example, exposing the patterned seed layer to zinc vapor in the presence of a trace amount of oxygen. The seed layer can alternatively be formed by using a spin-on technique, such as a metal organic deposition technique, a spray pyrolisis technique, an RF sputtering technique or by oxidation of a zinc thin film layer formed on the substrate.

Abstract: An optical element and a manufacturing method therefor, an exposure apparatus, and a device manufacturing method that can reduce the effect of intrinsic birefringence under high NA conditions. According to an optical element as one aspect of the present invention, an angle between a [0 0 1] axis of an isometric crystal and an optical axis is less than 10°, and preferably 0°.

Abstract: A method is described for making low-stress single crystals with a hexagonal crystal structure, which has a crystallographic c-axis perpendicular to a [0001] surface. A single crystal maintained at a temperature under the melting point of the crystal raw material is dipped in a melt of the crystal raw material, whereby a solid-liquid phase boundary is formed. The crystal is subsequently drawn with an upwardly directed drawing motion e.g. by the Czochralski method. The method is characterized by drawing the crystal along the c-axis so that a temperature gradient of at least 30 K/cm is present in the crystal within a centimeter of the solid-liquid phase boundary and by subsequently performing a tempering treatment on the resulting single crystal. The method is especially suitable for corundum crystals, such as sapphire, which are used as substrates for semiconductor components, such as LEDs.

Abstract: A method of manufacturing a potassium niobate (KNbO3) single crystal thin film, includes the steps of maintaining the substrate under a predetermined oxygen partial pressure; maintaining the substrate within a temperature region which is equal to or higher than an eutectic temperature of KNbO3 and 3K2O.Nb2O5 and is equal to or lower than complete melting temperature of KNbO3 and 3K2O.Nb2O5 so that a solid phase of KNbO3 and a liquid phase can coexist on the substrate; depositing a vapor phase material on the substrate in a state in which a solid phase and a liquid phase coexist; and precipitating KNbO3 on the substrate from the liquid phase as a solid phase to grow a KNbO3 single crystal thin film. The composition of a starting material to be vaporized to generate the vapor phase material is from K2O.Nb2O5=50:50 to K2O.Nb2O5=65:35.

Abstract: ?-ZrNCl polycrystalline powder prepared by chemical transport method and NH4Cl are mixed in a molar ratio of 1:2. The mixture is encapsulated in a Au capsule (6 mm in inner diameter and 6 mm in depth) of a reaction vessel 2, which is then enclosed in a highly heat-conductivitive sodium chloride block as an electrically insulating pressure medium 6. The mixture held in the sodium chloride block is placed in a carbon tube 8 for serving as a heater. In a cubic-pressing apparatus using a pyrophyllite 12 as a pressure-transmitting medium, the mixture is heated at 900° C. for 2 hours under an applied pressure of 3 GPa. After the mixture is allowed to stand until it is cooled down to room temperature, the Au capsule is taken out and light green ?-ZrNCl single crystals are obtained. A large single crystal among them had a hexagonal plate-like habit and is transparent with dimensions about 2 mm in diameter, and 0.3 mm in thickness.

Abstract: A thermal treatment process for improving the resistance of a flux grown, periodically poled KTiOPO4 crystal to photorefractive or photochromic damage comprising the steps of: i) heating said crystal from ambient temperature up to an annealing temperature in the range of from about 200° C. to about 400° C.; ii) maintaining said crystal at said annealing temperature in an oxygen containing atmosphere; iii) allowing said crystal to slowly cool down from said annealing temperature to ambient temperature.

Abstract: An apparatus for making a crystal pre-melt includes a hermetically-sealed muffle furnace made of a non-porous refractory material, at least one port for entry and exit of gaseous substance within the muffle furnace, a temperature-controlled zone defined inside the muffle furnace, and a crucible for holding crystal raw material in solid or molten form inside the muffle furnace. The crystal pre-melt is made by disposing crystal raw material in loose powder, pressed powder, granular, or densified form in the temperature-controlled zone, heating the temperature-controlled zone to a treatment temperature that enables reaction between a fluorinating agent and oxides in the crystal raw material, reacting the fluorinating agent with the crystal raw material to produce volatile gases, removing the volatile gases from the muffle furnace, heating the crystal raw material to form a melt, and solidifying the melt to form the crystal pre-melt.

Abstract: A single crystal pulling apparatus for a metal fluoride comprising a crucible provided in a chamber for filling with a molten solution of a single crystal material, a melting heater provided to surround the crucible, a vertically movable single crystal pulling bar for attaching a seed crystal on a tip thereof for coming in contact with the molten solution of the single crystal material in the crucible, a heat insulating wall provided in the chamber to surround at least a peripheral side portion of a single crystal pulling region in an upper part of the crucible, a ceiling board for closing an opening portion of an upper end in an upper part of the heat insulating wall, and a single crystal pulling chamber surrounded by the heat insulating wall and the ceiling board, wherein the ceiling board is provided with at least an inserting hole for inserting the single crystal pulling bar, and wherein a coefficient of thermal conductivity in a direction of a thickness of the ceiling board is 1000 to 50000 W/m2·K.

Abstract: The invention is directed to method of preparing metal fluoride single crystals and particularly to crystals where the metal is calcium, barium, magnesium or strontium, or a mixture thereof. The invention uses a decreasing fast cooling profile and an increasing slow cooling profile for the hot zone and the cold zone, respectively, after crystal formation during cooling from melt temperatures to a first temperature. A substantially constant cooling rate is then applied to the both zones during cooling from the first temperature to a final temperature, usually room temperature. It has been found that the substantially constant cooling rate during the annealing process results in crystals having improved homogeneity and birefringence.

Abstract: In order to prevent a region of supercooling from increasing and to effect uniform crystal growth, the generation of latent heat is detected from changes in temperature of a crucible or a heater or from changes in heat flow rate and also the position of solid-liquid interface is mathematically found, to control the crucible-descending rate or temperature distribution so that the crystal growth rate can be kept at a predetermined value.

Abstract: A calcium fluoride crystal produced in accordance with a method for producing calcium fluoride crystal on the basis of refining a raw material of calcium fluoride and causing crystal growth of the refined calcium fluoride, the method including a process of raising a purity of the calcium fluoride to complement the refining, wherein a transition density in crystal is not greater than 1×105/cm2, and that dispersion of transition density inside an effective portion in crystal is in a range of ±5×104/cm2. Also disclosed is an optical element to be manufactured by use of such CaF2 crystal.

Abstract: A method for manufacturing fluoride crystal includes the steps of adding scavenger and a material to a crucible, melting the scavenger and material at a temperature higher than a melting point so that a ratio of a thickness of the fluoride crystal that has been melted to an inner diameter of the crucible may be 0.2 or higher, and gradually crystallizing and purifying the material.

Abstract: A method of making a fluoride crystal suitable for use as an optical element is disclosed. The method includes a mixing step for mixing a prepared raw fluoride material with a scavenger to yield a fluoride mixture. In a preliminary step, the fluoride mixture is formed into a fluoride disk. A grown fluoride crystal is formed by melting and then gradually cooling the fluoride disk in a cylindrical crucible. The grown fluoride crystal is then annealed.

Abstract: A production apparatus for producing a crystal includes a crucible divided into a plurality of stages, each stage containing a crystal precursor material, and a heater arranged to heat the crucible. The crucible has formed therein a degassing hole in a side wall portion thereof for discharging an impurity gas produced when refining the crystal precursor material by adding a scavenger thereto, and a lower portion of a first stage of the plurality of stages is positioned to cover an upper edge of a wall portion of a second stage of the plurality of stages. The overall height of the plurality of stages is 10 mm to 50 mm, the degassing hole has a diameter of 1 mm to 5 mm, and a fluoride crystal is formed from the crystal precursor material.

Abstract: The object of the present invention is a process of preparing an optical fluoride crystal containing barium fluoride, which comprises: loading a crucible with a barium fluoride starting material crystal feedstock which contains at least one oxide as impurity, and an effective and non-excess amount of at least one fluorinating agent which is solid at ambient temperature, melting said mixture within said crucible, growing the crystal, by controlled cooling of the molten mixture, controlled cooling of said crystal to ambient temperature, recovering said crystal; and which is characterized in that the oxide(s) resulting from the reaction between said fluorinating agent(s) and said oxide(s), the impurity or impurities, can be discharged from said crucible, in view of the intrinsic permeability of the material constituting it. Said process is particularly adapted for preparing 157 nm transmitting lithography excimer laser optical fluoride crystals in graphite crucibles.

Abstract: A manufacturing method for a single crystal of calcium fluoride by which it is possible to obtain a single crystal of calcium fluoride with adequately small double refraction, which can be used in optical systems for photolithography, and in particular, a single crystal of calcium fluoride with a large diameter (ø200 mm or larger) having superior optical properties, which can be used for photolithography with a wavelength of 250 nm or less.

Abstract: The invention provides a UV below 200 nm lithography method utilizing mixed calcium strontium fluoride crystals. The invention includes providing a below 200 nm radiation source for producing <200-nm light, providing a plurality of mixed calcium strontium cubic fluoride crystal optical elements, with the fluoride crystals comprised of a combination of calcium strontium cations having different optical polarizabilities such as to produce an overall isotropic polarizability which minimizes the fluoride crystal spatial dispersion below 200 nm, transmitting <200-nm light through the cubic fluoride crystal optical elements, forming a lithography pattern with the light, reducing the lithography pattern and projecting the lithography pattern with the fluoride crystal optical elements onto a UV radiation sensitive lithography printing medium to form a printed lithographic pattern. The invention includes making the mixed fluoride crystals, optical element blanks thereof and optical lithography elements.

Abstract: The method of heat-treating a fluoride crystal according to the present invention comprises introducing an inert gas and/or a fluorine-based gas into a heat-treating furnace in which a fluoride crystal is placed through a gas-feeding port, and heating the fluoride crystal in the atmosphere of the gas having a pressure not lower than atmospheric pressure, thereby making it possible to prevent turbidity and coloration generated in the fluoride crystal due to oxygen and metal impurities adsorbed by the surface of the fluoride crystal.

Abstract: In order to shorten the annealing time to thereby reduce the production cost of a fluoride crystal, the method of heat treating a fluoride crystal of the present invention comprises the steps of: raising the temperature of a fluoride crystal; reducing the raised temperature of the fluoride crystal at a first temperature reducing rate; and then reducing the temperature of the fluoride crystal at a second temperature reducing rate which is larger than the first temperature reducing rate.

Abstract: A method for growing solid state laser crystal boules is disclosed that when made into laser rods do not need separate end caps attached to the laser rods. The crystal boule is grown as a single integral unit with three segments. Two segments, the end segments, are un-doped or non-laser active, and they flank a central segment of the boule that is doped with an active laser ion. A first end segment of the crystal boule is first grown from un-doped melt material in a first crucible by slowly withdrawing its growing end from the first melt. The boule is then transferred to a doped melt in a second crucible where its growing end is submersed therein to grow the doped, laser active central segment. The temperature of the melt in the second crucible is initially higher than the growing temperature of the first melt and causes the growing end of the boule to melt.

Abstract: A birefringence minimizing fluoride crystal vacuum ultraviolet (“VUV”) optical lithography lens element is provided for use with lithography wavelengths<230 nm. The VUV lithography lens element has an optical axis encompassed by a lens perimeter with the fluoride crystal lens having a variation in crystallographic orientation direction which tilts away from the optical center axis towards the lens perimeter to provide minimal birefringence. The invention includes a birefringence minimizing fluoride crystal optical lithography lens blank with a variation in crystallographic orientation direction across the blank.

Abstract: The invention provides a method of making UV<200 nm transmitting optical fluoride crystals for excimer laser lithography optics and a multicompartment container for growing optical fluoride crystals, comprising a number of graphite bowls that are placed on top of one another to form a stack and which have a central conical orifice in the bottom of each of them, and also comprising a seeding unit that has a central cylindrical orifice and is arranged under the lowermost bowl, characterized in the each bowl is fitted with a heat-removing device that is made in the form of a graphite cylinder with a central conical orifice, is mounted under the bottom of each bowl, and adjoins, with its other surface, the cover of the next bowl down, in which design the cover of each bowl, apart from the uppermost one, has a central conical orifice.

Abstract: The present invention provides below 160 nm optical lithography crystal materials for VUV optical lithography systems and processes. The invention provides fluoride optical lithography crystals for utilization in 157 nm optical microlithography elements which manipulate below 193 nm optical lithography photons. The present invention provides methods of making below 160 nm optical lithography crystal materials for below 160 nm VUV optical lithography systems and processes.

Abstract: A crystal growth station including a cylindrical crucible having powered bottom and top resistance heaters mounted below and above the crucible, respectively. A supplemental heating unit is positioned around the bottom edge of the crucible. The supplemental heating unit may be unpowered or powered to heat it independently of the top and bottom heaters. If unpowered, then the supplemental heating unit is formed of a cylinder around the lower portion of the crucible side wall and a washer shaped disk member extending under part,of the crucible bottom wall. The supplemental heating unit is generally wedge shaped. The supplemental heating unit is heated by radiation from the bottom heater. The heat is conducted from the disk to the cylinder. A supplemental heater may be similarly used at the top edge of the crucible. If powered, the cylinder and the disk have slits therein to form current paths.

Abstract: The present invention provides fluoride lens crystals for VUV optical lithography systems and processes. The invention provides a barium fluoride optical lithography crystal for utilization in 157 nm optical microlithography elements which manipulate below 193 nm optical lithography photons. The invention includes a barium fluoride crystalline material for use in dispersion management of below 160 nm optical lithography processes.

Abstract: A crystal filter and a method of making a crystal filter capable of transmitting radiation within a particular pass band is disclosed. The crystal filter is particularly appropriate for a UV detection system, where the pass band is between about 200 to about 350 nm. A UV detection system incorporating the crystal filter is also described. One embodiment of crystal filter is formed from a single-crystal transparent host, such as a fluoride host, codoped with lanthanide or actinide fluorides and lanthanide or actinide nitrides, oxides, borides, carbides or hydroxides. Filter crystals according to the present invention can be grown by various crystal growth methods, including Czochralski and Bridgeman crystal growth methods.