17results about "Using seed in melt" patented technology

The utility model discloses a tungsten-copper alloy heater for sapphire crystal growth, and relates to the technical field of sapphire crystal growth equipment. The heating device comprises a mounting seat, a supporting frame is fixedly connected to the bottom of the mounting seat, a heating rod is arranged at the bottom of the mounting seat, a tungsten-copper alloy electrode is arranged at the top of the mounting seat, a clamping device is arranged at the top of the mounting seat, the clamping device comprises a sliding groove, the sliding groove is formed in the top of the mounting seat, and the tungsten-copper alloy electrode is arranged in the sliding groove. The inner wall of the sliding groove is fixedly connected with a mounting block. The birdcage heater made of the tungsten copper alloy is not prone to deformation, meanwhile, a good temperature gradient and a uniform and stable temperature field are provided for sapphire crystal growth, stable crystal growth is achieved, meanwhile, the service life of the heater is prolonged, equipment damage caused by improper operation can be reduced, and the service life of the heater is prolonged. And the maintenance cost caused by frequent misoperation is reduced.

The invention discloses a growth method for preparing a high-strength sapphire crystal through a kyropoulos method, and belongs to the technical field of artificial crystal growth. The mechanical strength and damage resistance of the sapphire single crystal are remarkably improved by optimizing the kyropoulos growth process. The invention particularly relates to a technology for obtaining a sapphire crystal with high bending strength, high fracture toughness and excellent thermal shock resistance by regulating and controlling thermal field distribution, an interface stress state and a defect evolution behavior in a growth process.

To provide an apparatus for manufacturing oxide single crystals, a method for manufacturing gallium oxide single crystals using the apparatus, and a gallium oxide single crystal manufactured thereby. [Solution] By applying a method that uses the oxide pellet itself, which is to be made into a single crystal, as the crucible without using a separate crucible, the problem of impurities entering due to the crucible is minimized. Furthermore, by applying a method that mixes hydrocarbon fuel gas and oxygen gas and generates heat using a flame, the growth atmosphere for the oxide single crystal can be maintained in a high-oxygen atmosphere, enabling the production of high-quality oxide single crystals with few defects.

The invention relates to a sapphire single crystal (4) and a method and apparatus (1) for producing it, wherein the sapphire single crystal (4) comprises a plurality of layers (11) arranged in a C-axis (7), wherein each layer (11) has a cross-sectional topography (12), wherein the cross-sectional topographies (12) of the layers (11) repeat with respect to geometric patterns (13) formed in the cross-sectional topographies (12), wherein the geometric patterns (13) are predominantly composed of polygonal rings, in particular of concentric hexagonal or concentric hexagonal rings.

This invention discloses a barium borate crystal, its preparation method, and its applications. The barium borate crystal has the chemical formula Ba₂BeB₂O₆, a non-centrosymmetric structure, belongs to the orthorhombic crystal system, has the space group Pca₂₁, and its cell parameters are α = 90°, β = 90°, and γ = 90°. This barium borate crystal exhibits extremely low birefringence from the ultraviolet to the infrared band, and its extremely low birefringence supports its application on zero-order glass slides.

A method for growing a periodically polarized nonlinear crystal may include placing a seed crystal in a melt to form a seed crystal melt mixture, the seed crystal comprising at least one of strontium tetraborate (SBO) or lithium triborate (LBO), and the melt comprising at least one of a mixture of Sr, B, and O or a mixture of Li, B, and O. The method may further include heating the seed crystal melt mixture to a predetermined temperature until a periodically polarized nonlinear crystal is formed.

Disclosed herein is a rare earth oxyorthosilicate crystal having a formula (1): Lu2(1-a-b-c-d)A2aB2bC2c D2dSi(1-x+y)EyO5(1-z), wherein Lu is lutetium; A comprises a trivalent ionic substitution selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Sc, Y, Al, Ga, B, In, Bi, Sb, Au, Rh, or a combination thereof; B comprises a non-trivalent ionic substitution selected from Mg, Ca, Sr, Ba, Li, Na, K, Rb, Mn, Cu, Zn, or a combination thereof; C comprises an activating cation substitution selected from Ce3+, Ce4+, Pr3+, or a combination thereof; D comprises a monovalent halogen anion substitution selected from F, Cl, Br, or a combination thereof; E comprises a trivalent ion substitution selected from La, Sc, Y, Al, Ga, In, B, In, Bi, Sb, Au, Rh, or any combination of thereof.

The present invention relates to an apparatus for preparing an oxide single crystal, a method for preparing a gallium oxide single crystal using the same, and a gallium oxide single crystal prepared according to the method, and more particularly, to an apparatus for preparing a single crystal and a method for preparing a gallium oxide single crystal using the same, according to the present invention, a method in which oxide particles for producing a single crystal are used as a melting furnace instead of oxide particles per se for producing a single crystal is used as the melting furnace, thereby minimizing the problem of impurity inflow through the melting furnace, and the growth atmosphere of the oxide single crystal is maintained at a high oxygen atmosphere by using a method in which a hydrocarbon fuel gas and oxygen are mixed and heat is released by spark. Therefore, the high-quality oxide single crystal can be prepared.

This invention belongs to the field of crystal material preparation technology and discloses a method for growing large-size, high-purity PMN single crystals using a top-seeded crystal growth method. It employs a gradient molten salt single crystal furnace equipped with a hollow oxygen-bearing seed crystal rod and a bidirectional rotation mechanism. The seed crystal rod and crucible rotate in opposite directions. By optimizing the composite flux ratio and identifying the drawbacks of excessively high / low ratios, adopting an extremely low cooling rate adapted to the temperature sensitivity of PMN, and designing a staged speed control strategy that precisely correlates crystal outline size with rotation speed, combined with temperature field optimization due to the opposite rotation of the seed crystal and crucible, and nucleation control through oxygen-bearing at the seed crystal to create a cold end, the crystal outline size is observed at high temperature, and process parameters are adjusted in real time to achieve high-purity growth of large-size PMN single crystals. The final obtained PMN single crystals are verified by XRD, scanning electron microscopy, EDS energy dispersive spectroscopy, and dielectric temperature spectroscopy to be free of impurities and have a pure crystal form. The single crystal size breaks through the large-size level and has good formability, meeting the application requirements of devices in the fields of electronics, piezoelectrics, and optics.

The invention provides a compound lithium barium boron oxygen fluorine nitro and a lithium barium boron oxygen fluorine nitro nonlinear optical crystal and a preparation method and application thereof, the chemical formula of the compound is LiBa3B9O16FNO3, the molecular weight is 853.27, and the compound is prepared by adopting a solid-phase synthesis method; the chemical formula of the compound of the crystal is LiBa3B9O16FNO3, the molecular weight is 853.27, the compound belongs to a trigonal system, the space group is P31c, the cell parameters are as follows: a = 10.1393 (7), b = 10.1393 (7), c = 8.6977 (8), alpha = 90 degrees, beta = 90 degrees, gamma = 120 degrees, the unit cell volume is 774.37 (13) 3, the frequency-doubled effect of the crystal is about 1-3 times that of KH2PO4 (KDP), the ultraviolet cut-off edge is about 208 nm, the crystal is grown by adopting a melt method, a high-temperature melt method or a vacuum packaging method, the chemical stability of the crystal is good, and the crystal is suitable for industrial production. The crystal can be used as a short-wavelength ultraviolet nonlinear optical crystal in an all-solid-state laser.

The present disclosure relates to an apparatus for producing an oxide single crystal, a method of producing a gallium oxide single crystal using the same, and a gallium oxide single crystal produced thereby. More specifically, the present disclosure relates to an apparatus for producing a single crystal and a method for producing a gallium oxide single crystal using the same, which may minimize the problem of impurities being introduced by a crucible, by applying a method of using the oxide pellets themselves, which are to be made into a single crystal, as a crucible without using a separate crucible, and maintain the growth atmosphere of the oxide single crystal at a high-oxygen atmosphere by applying a method of generating heat using a flame consisting of a mixture of a hydrocarbon fuel gas and oxygen gas, thereby producing a high-quality oxide single crystal with few defects.

The invention relates to the technical field of crystal growth, in particular to a fluxing agent for growing SrB4O7 crystals and application of the fluxing agent. According to the invention, by introducing a specific fluxing agent system composed of one or two of Li2O and Sr2V2O7, the growth mode of the SrB4O7 crystal is changed from the traditional melt method growth to the fluxing agent method growth. The fluxing agent is effectively introduced, so that the actual growth temperature of the crystal is greatly reduced. Meanwhile, the fluxing agent system enhances the capability of resisting external tiny temperature disturbance of the melt, so that the crystal growth process can be stably carried out in a wider and easier-to-control temperature range, the harsh requirement on the temperature control precision is greatly reduced, and the stability and repeatability of the process are improved.

The invention relates to a compound sulfur-gallium-aluminum and sulfur-gallium-aluminum infrared nonlinear optical crystal and a preparation method and application thereof, the molecular formula of the compound is AlGaS3, the molecular weight is 192.88 g / mol, the compound has an asymmetric center, is crystallized in a Cc space group of a monoclinic system, and the cell parameters are as follows: a = 11.1401 (5), b = 6.4092 (3), c = 7.0147 (3), beta = 121.417 (2) degrees, Z = 4, and the volume is 427.42 (3) 3. The crystal is prepared by adopting a high-temperature melt method, a chemical vapor transport method, a fluxing agent method or a Bridgman-Stockbarger method. The crystal has the advantages of being high in laser damage resistance, moderate in nonlinear optical effect, wide in light-transmitting wave band, large in hardness, good in mechanical performance, not prone to fragmentation and deliquescence, easy to process and store and the like, and can be used for manufacturing infrared nonlinear optical devices.

The present invention belongs to the technical field of the growth of sapphire crystals, and specifically relates to a method for controlling impurities during the growth of sapphire crystals, and a crucible for crystal growth. The method for controlling impurities during the growth of sapphire crystals comprises the following steps: crucible impurity removal, involving spraying an aluminum oxide solution onto the inner wall of a molybdenum crucible, placing the crucible into a crystal growing furnace, sealing a furnace body, and then starting heating for sintering, followed by cooling; and crystal growing, involving filling the treated crucible with a raw material powder, i.e. aluminum oxide, sealing the furnace body, then starting heating to melt the raw material, performing seeding and crystal growing after the raw material has melted, and after the growth of crystals is completed, cooling same and then taking out the crystals. Mainly by designing and controlling the reaction of aluminum oxide at different temperatures, a crucible for crystal growth is obtained by means of an impurity removal operation on the crucible, thereby preventing impurity elements in a new crucible from being introduced into the growth process of sapphire crystals; therefore, impurities during the growth of sapphire crystals are controlled, and the quality and consistency of crystal growth are improved.

The present invention relates to compounds and their nonlinear optical (NLO) crystals of A2REB3O6F2 (A=Rb, Cs, NH4; RE=Sc, Y, La), their producing method and uses thereof. The series of compounds have a chemical formula of A2REB3O6F2 (A=Rb, Cs, NH4; RE=Sc, Y, La), which are namely Rb2ScB3O6F2, Cs2ScB3O6F2, (NH4)2ScB3O6F2, Rb2YB3O6F2, Cs2YB3O6F2, (NH4)2YB3O6F2, Rb2LaB3O6F2, Cs2LaB3O6F2 and (NH4)2LaB3O6F2. The series of NLO crystals having the chemical formula of A2REB3O6F2 (A=Rb, Cs, NH4; RE=Sc, Y, La), belong to orthorhombic crystal system, and have a space group of Amm2, crystal cell parameters of a=2.7182(4)−4.9617(8)Å, b=7.7013(5)−9.9742(6)Å, c=10.2634(1)−12.904(3)Å, Z=2. A2REB3O6F2 (A=Rb, Cs, NH4; RE=Sc, Y, La) compounds were prepared by a solid-state reaction method or a hydrothermal method, and A2REB3O6F2 (A=Rb, Cs, NH4; RE=Sc, Y, La) NLO crystals were prepared by a high-temperature solution method, a hydrothermal method, or a solution method. They meet the requirements for the frequency conversion of UV wavelength lasers and could be used to prepare nonlinear optical devices.

The present invention relates to a transition metal element-doped garnet-type aluminate scintillation material with high-quality factor and preparation method and application thereof. The transition metal element-doped garnet-type aluminate scintillation material has a chemical formula of RE3-x-aCexAaAl5-y-zDyMzO12, wherein 0<x≤0.15, 0≤y≤3, 0<z≤0.1, and 0≤a≤0.1; RE is a rare earth element selected from at least one of Gd, Lu, Y, Sc, La, Nd, Eu, Tb, Dy, Ho, Er, Tm, and Yb; A is selected from at least one of Li, Mg, Ca, K, and Na; D is selected from at least one of Ga and In; and M is a transition element selected from at least one of Cr, Mn, Fe, Co, and Ni.

A crystal growth method and a crystal growth device, relating to the technical field of multi-component crystal preparation. A pure melt Kyropoulos method is used to grow multi-component crystals, and the multi-component crystals are binary and higher oxides. The crystal growth device comprises a furnace, a supporting seat, a crucible, a seed rod, an air outlet pipe, an air inlet pipe, and three annular heating assemblies, wherein the furnace comprises a furnace body and a furnace cover, the furnace cover seals a top opening of the furnace body, and a heating zone enclosed by a thermal insulation material is provided inside the furnace body; the supporting seat and the crucible are both arranged in the heating zone; the seed rod extends into the crucible; the three annular heating assemblies are arranged on the inner wall of the heating zone, the three heating assemblies are respectively an upper heating assembly, a middle heating assembly and a lower heating assembly which are arranged at intervals from top to bottom, and the crucible is located in a medium-temperature zone surrounded by the middle heating assembly. The crystal growth method can avoid the polycrystalline phenomenon and internal defects, grow larger-size and high-quality multi-component crystals, and reduce production and manufacturing costs.