CN103789832A - Nested crucible for growing strontium iodide crystal and method for growing strontium iodide crystal - Google Patents
Nested crucible for growing strontium iodide crystal and method for growing strontium iodide crystal Download PDFInfo
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- CN103789832A CN103789832A CN201410053534.0A CN201410053534A CN103789832A CN 103789832 A CN103789832 A CN 103789832A CN 201410053534 A CN201410053534 A CN 201410053534A CN 103789832 A CN103789832 A CN 103789832A
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Abstract
The invention relates to a nested crucible for growing a strontium iodide crystal and a method for growing the strontium iodide crystal. The nested crucible comprises an inner layer crucible for holding a crystal growing raw material and an outer layer crucible which is used for providing a sealed environment and can be vacuumized, wherein the outer layer crucible is a quartz crucible, and the inner layer crucible is a metal-based crucible or carbon-based crucible; the outer layer crucible is longer than the inner layer crucible in order to enclose the inner layer crucible completely after being sealed; the distance between the outer wall of the inner layer crucible and the inner wall of the outer layer crucible is not smaller than 0.6 millimeter. In the nested crucible, the advantages of the quartz crucible, the metal-based crucible and the carbon-based crucible are combined, and respective disadvantages are eliminated effectively, so that the nested crucible can be used for growing high-quality non-doped and doped strontium iodide crystals.
Description
Technical field
The present invention relates to a kind of method of crucible for the strontium iodide crystal of growing and growth strontium iodide crystal, be specifically related to a kind of nested type crucible and use the method for this nested type crucible growth strontium iodide crystal, belong to crystal technique field, particularly halide crystal growing technology field.
Background technology
Inorganic scintillator can be used for fast, determines sensitively and accurately the gamma-rays characteristic of highly enriched uranium, weapons-grade plutonium, radioactive source and other special nucleus raw material, has a wide range of applications in radiation detection fields such as Radionuclides identification, safety inspection, environmental monitoring, chemical and biological weapons verification, low energy nuclear test and nuclear non-proliferation verifications.In recent years, increasingly serious along with global Nuclear safety and terrified situation, and the raising of people's Radiation Environment Safety consciousness, also increased day by day to the demand of high-performance scintillator more.At present, a kind of scintillator being most widely used in above-mentioned field is NaI:Tl crystal, but the energy response disproportional of NaI:Tl crystal and energy resolution poor-performing, and as the hypertoxic Tl of activator ion
+a large amount of uses of ion, the potential safety hazard that also exists environment to be polluted.The scintillation material LaBr of a new generation
3: Ce crystal has good scintillation properties, but this material exists serious cleavage or stress cracking, melt easily and crucible react, raw material and preparation cost are all higher, also contain simultaneously and can produce radioactive background
138la isotopic composition, its application in radiation detection field has been subject to larger restriction.
As far back as 1969, U.S. Robert Hofstadter just applied for Eu
2+doping strontium iodide (SrI
2: Eu) crystal is as the patent of radiation detection material, but owing to preparing at that time the second-rate of crystal, performance is than business-like Tl
+ion doping NaI crystal there is no advantage, and its correlative study is subsequently absorbed in the silence of nearly 40 years.Until 2008, under department's business models such as Homeland Security office of the U.S. and Ministry of Energy, preparing high-quality SrI
2: after Eu crystal, the people such as Nerine Cherepy re-recognize SrI
2: the excellent scintillation properties of Eu, strontium iodide is just subject to the attention in inorganic scintillator field again as a kind of scintillator, and associated research becomes rapidly inorganic scintillator study hotspot and forward position.Their research shows, SrI
2: the light output of Eu can reach 120,000ph/MeV, is the highest inorganic scintillator of known light output, has splendid energy resolution (<3%), has good energy linearity in wider energy region.In addition, strontium iodide has lower fusing point (538 ℃), without cleavage, from melting temperature to room temperature range in without phase transformation, very easily adopt falling crucible method to realize mass-producing, industrialization preparation.
Prepare in crystallization process at falling crucible method, crucible is to hold and the container of melt raw material, also be the container of crystal growth, high-temperature fusant directly contacts with crucible, and therefore its shape, size, structure and physicochemical characteristic have a great impact the quality, size and the performance that grow crystal.
Strontium iodide is alkaline earth metal halide, easily deliquescence and oxidation, and the current crystal the most frequently used crucible of growing is quartz crucible, by anhydrous high-purity SrI
2and EuI
2raw material packs quartz crucible into after weighing in proportion mixing, after vacuumizing, by quartz crucible sealing by fusing, carries out crystal growth under air atmosphere.Vacuumize and sealing by fusing after, the environment of realizing growth raw material and the crucible external world is completely isolated.But select quartz crucible growth strontium iodide, also have certain problem: on the one hand, the thermal expansivity (0.6 × 10 of quartz crucible
-6℃
-1) and strontium iodide Thermal Expansion in Crystals coefficient (0.9-2.1 × 10
-5℃
-1) there is larger difference, in crystal growing process, crystals can accumulate larger stress, often occurs the phenomenon of crystal cleavage in crystal growth or temperature-fall period; In addition on the one hand, experimental studies have found that, normal and the quartz crucible of the melt of strontium iodide is had an effect, quartz crucible inner side is corroded, form one deck duricrust growing plane of crystal, when serious, can make crucible burst, this has a strong impact on the quality and performance that grows crystal, even causes crystal to be grown unsuccessfully.
The crucible of metal matrix, if single metal is as the crucible of aluminium, platinum, iraurite, tungsten and molybdenum making, or the crucible of being made by the alloy of two or more metal, if it is suitable to select, can avoid reacting of melt and crucible material, and because metal matrix crucible generally has good ductility, can greatly reduce the stress of assembling in crystal growing process, can greatly reduce the probability of crystal cleavage; Metal matrix crucible has easy to processly in addition, and the feature that can reuse, is suitable for the mass preparation of large-size crystals.The people such as Qin Laishun have applied for adopting the patent of antivacuum Bridgman-Stockbarge method for growing strontium iodide method, and reductor and raw material are positioned in metallic crucible, will after metallic crucible sealing, adopt Bridgman-Stockbarge method for growing.But the shortcoming of metal matrix crucible is the evacuation process that cannot adopt similar quartz crucible method, generally under zero relative pressure, to carry out flame welding seal operation, in welding, inevitably to introduce oxygen and water molecules, generally can dose the internal medium of reducing a little less than reductor is built, to crystal, growth has brought new challenge in the introducing of reductor; In addition, when melt is under high temperature, crucible internal pressure is very large, easily causes crucible explosion, causes environment to completely cut off complete failure, causes crystal to grow unsuccessfully.
The crucible of carbon back, as plumbago crucible or vitreous carbon crucible, has good chemical stability, can design and effectively eliminate structure, and generally not react with raw material, but this class crucible cannot be realized good sealing, be usually used in unsealed breaking of vacuum method growth halide crystal, as BaF
2, CeF
3, MgF
2deng.In unsealed breaking of vacuum method process, need to be to crucible, heating and heat-insulation system pumping high vacuum incessantly, equipment is comparatively huge; In addition, for general halide crystal growth, can cause melt acutely to volatilize, volatile matter also can produce larger impact to vacuum system and external environment.
Summary of the invention
In the face of the problem that prior art exists, the object of the present invention is to provide a kind of method of nested type crucible growth strontium iodide crystal of simple to operate, with low cost, applicable mass, to realize this crystal-like suitability for industrialized production.
The relative merits that respectively have for quartz crucible, metal matrix and carbon back crucible, the present invention recognizes if merges preferably three's advantage, and effectively reduces or eliminate their inferior positions separately, is expected to open up an effective approach for the growth of strontium iodide crystal.
At this, on the one hand, the invention provides a kind of nested type crucible for the strontium iodide crystal of growing, described nested type crucible comprises for the inner crucible of growing crystal with for the outer crucible of vacuum-pumping of sealed environment is provided, wherein said outer crucible is quartz crucible, and described inner crucible is metal matrix crucible or carbon back crucible; Described outer crucible is longer than described inner crucible, can surround described inner crucible completely after sealing by fusing; Spacing between the outer wall of described inner crucible and the inwall of described outer crucible is not less than 0.6mm, is preferably 0.6～1mm.
Nested type crucible of the present invention combines the advantage of quartz crucible, metal matrix and carbon back crucible, has effectively eliminated their inferior positions separately, thereby can be for the growth of high-quality non-doping and doping strontium iodide crystal.Wherein, metal matrix provided by the present invention/quartzy nested type crucible, both avoided the impact of component volatilization on pumped vacuum systems, suppressed again reacting of melt and quartz crucible, the size and dimension that grows crystal is easily controlled, and crystal stress is little, not easy to crack, the perfection of crystal growing is good, and the yield rate of growth is high, is suitable for suitability for industrialized production.In addition, carbon back provided by the present invention/quartzy nested type crucible combine carbon back easily design eliminate structure, eliminate success ratio high, not with the advantage of fusant reaction, and the feature of the easy sealing by fusing of quartz crucible, crystal growing process can complete in the crucible decline stove under air atmosphere, avoid the use of huge high vacuum growth apparatus, the volatilization of melt has obtained farthest restriction, has simple in structurely, is easy to mass and industrialized feature.
Preferably, the bottom of described inner crucible is formed as having the structure of spontaneous superseded function.Like this, can be without using seed crystal in crystal growing process.
Preferably, the SiO of described quartz crucible
2content be not less than 99.99%.
Preferably, the material of described metal matrix crucible is any one metal in aluminium, platinum, iridium, tungsten and molybdenum or the alloy of any two or more metals.
Preferably, described carbon back crucible is plumbago crucible or vitreous carbon crucible.
On the other hand, the invention provides a kind of method that adopts above-mentioned nested type crucible growth strontium iodide crystal, comprising:
(1) the crystal growth raw material that contains high-purity strontium iodide and high-purity doping agent is packed in the inner crucible of above-mentioned nested type crucible in not higher than 5% environment in humidity;
(2) under vacuum condition, described crystal growth raw material is heated to 300～450 ℃, and is incubated 2～20 hours and carries out pre-treatment;
(3) keeping, under the state vacuumizing, the nested type crucible that fills pretreated raw material is cooled to room temperature, the outer crucible of sealing by fusing; And
(4) the nested type crucible after sealing by fusing is inserted to crucible degrowth stove, carry out crystal growth by falling crucible method.
In the present invention, adopt nested type crucible, by Bridgman-Stockbarge method for growing strontium iodide crystal, simple to operate, low for equipment requirements, with low cost, applicable mass, can realize high-quality non-doping and the suitability for industrialized production of the strontium iodide crystal that adulterates.By adopting metal of the present invention/quartzy nested type crucible growth strontium iodide crystal, both avoided the impact of component volatilization on pumped vacuum systems, suppress again reacting of melt and quartz crucible, the size and dimension that grows crystal is easily controlled, crystal stress is little, not easy to crack, and the perfection of crystal growing is good, the yield rate of growth is high, is suitable for suitability for industrialized production.By adopting carbon back of the present invention/quartzy nested type crucible growing crystal, combine carbon back easily design eliminate structure, eliminate success ratio high, not with the advantage of fusant reaction, and the feature of the easy sealing by fusing of quartz crucible, crystal growing process can complete in the crucible decline stove under air atmosphere, avoid the use of huge high vacuum growth apparatus, the volatilization of melt has obtained farthest suppressing, have simple in structure, with low cost, be easy to mass and industrialized feature.
Preferably, in step (1), described humidity is not or not water and oxygen level be not all higher than the inert ambient environment of 1000ppm higher than 5% environmental optimization.
Preferably, in step (2), described vacuum condition is that vacuum tightness is not higher than 0.1Pa.Preferably, vacuum tightness is 10
-3below Pa.
Preferably, in step (1), can adopt Eu
2+, Eu
3+, Tl
+, Pb
2+, Yb
2+and Yb
3+isoionic iodide, bromide, muriate or fluorochemical etc. are as doping agent, and doping content can be 0～10at%, and best doping content is relevant with doping ionic species; Also can not adopt doping agent, the strontium iodide crystal of the non-doping of growing.
Preferably, in step (4), described crystal growth comprises the following steps: at 2～10 hours fusing crystal growth raw materials of 550～700 ℃ of insulations; Control growth interface thermograde at 10～60 ℃/cm, carry out crystal growth with the speed decline crucible of 0.1～5.0mm/ hour; Crystal growth finishes rear furnace temperature and reduces by 50～100 ℃, and crystal and crucible are annealed 1～20 hour in position; And naturally cool to room temperature after cooling to 100 ℃ with the speed of 10～50 ℃/h.
Preferably, in crystal growth, can use seed crystal to inoculate growth, also can adopt spontaneous nucleation growth.
Accompanying drawing explanation
The structural representation that Fig. 1 is the crucible degrowth stove that adopts in example of the present invention;
Fig. 2 is the structural representation of the quartz/platinum nested type crucible with the superseded structure of capillary of an example of the present invention;
Fig. 3 is the structural representation of seed crystal inoculation growth quartz/platinum nested type crucible of an example of the present invention;
Fig. 4 is the structural representation of quartz/graphite nested type crucible with compound superseded structure of an example of the present invention.
Embodiment
Further illustrate the present invention below in conjunction with accompanying drawing and following embodiment, should be understood that accompanying drawing and following embodiment are only for the present invention is described, and unrestricted the present invention.In the accompanying drawings, identical key element is marked with identical symbol and omits repeat specification.
Fig. 1 illustrates the structural representation that carries out crystal growth institute employing crucible degrowth stove in example of the present invention.As shown in Figure 1, this growth furnace mainly comprises a temperature control device and crystal growing apparatus.Wherein a temperature control device can comprise insulating brick 1 and be arranged at the heating element 2 in insulating brick 1.Heating element 2 can adopt metal or alloy heating rod, wherein conventional with Si-Mo rod.By selecting different insulating bricks in different zones and the position of heating element 2 in insulating brick 1 being set, growth furnace can be arranged in to vertical direction and there is certain temperature distribution, be for example divided into successively from top to bottom high-temperature zone, gradient zones and cold zone.Carry out the fusing of crystal growth raw material in high-temperature zone; Carry out crystal growth in gradient zones.In addition, near the heating element 2 in insulating brick 1, temperature-control heat couple 3 can also be set, to control the temperature in this region.Temperature-control heat couple 3 for example can adopt platinum rhodium 10-platinum thermocouple (S type thermopair).A temperature control device that should be understood that above-mentioned example is only the Working environment for nested type crucible of the present invention is described, and unrestricted the present invention.
< nested type crucible >
Crystal growing apparatus mainly comprises nested type crucible 4.In growth furnace, can place single or multiple nested type crucibles 4.In addition, temperature thermocouple 5 can also be set with Real-Time Monitoring crystal growth temperature in the bottom of nested type crucible 4.Again, nested type crucible 4 can support with support crucible 6.
Fig. 2～4 illustrate the structural representation of the nested type crucible of three examples of the present invention.As shown in Fig. 2～4, nested type crucible 4 comprises inner crucible 7,7A, 7B and outer crucible 8.Inner crucible 7,7A, 7B are used for holding and melt raw material, and grow for crystal.In one example, inner crucible 7,7A, 7B are metal matrix crucible, its material can be single metal as aluminium, platinum, iridium, tungsten and molybdenum etc., can be also the alloy of two or more metal.In another example, inner crucible 7,7A, 7B are carbon back crucible, can be plumbago crucible or vitreous carbon crucible.The size and shape of inner crucible 7,7A, 7B can be determined according to treating the size and shape of growing crystal.For example its shape can be the shapes such as right cylinder, round platform, circular cone, rectangular parallelepiped, prismoid shaped or prism.Again, inner crucible can be the crucible shape of bottom with spontaneous superseded function.Especially in the time that inner crucible adopts carbon back crucible, be easy to design superseded structure.In the example shown in Fig. 2, the bottom of inner crucible 7 has capillary and eliminates structure 9.The internal diameter of capillary part can be 1/15～1/8 of top internal diameter, and length can be 1/6～1/3 of crucible overall length.In the example depicted in fig. 4, the bottom of inner crucible 7B has compound superseded structure 9B.Bottom and the top of this compound superseded structure 9B are capillary structure, and middle part is conical structure.By means of this, can in the capillary structure of bottom, form the least possible nucleus, and these nucleus are eliminated through amplifying again, finally enter the superseded structure in top and again eliminate, the good nucleus of remaining orientation occupies whole melt and develops into crystal.The bottom of inner crucible 7 can also be set to fix the structure of seed crystal, thereby goes for inoculating by seed crystal the situation of growth.For example, in the example of Fig. 3, can fix seed crystal 10 in the bottom of inner crucible 7A.Orientable or the non-directional of seed crystal, for example the seed crystal of optional [010], [100], [001] and any direction is inoculated growth.Inner crucible 7,7A, 7B can be sealed bottom, open-topped structure, can be also the structures of bottom and the equal opening in top.In the time of its bottom opening, can share its bottom surface with outer crucible 8.
Because strontium iodide is alkaline earth metal halide, easily deliquescence and oxidation, therefore its environment of crystal growth is preferably vacuum environment.In the present invention, can provide the vacuum environment of sealing by outer crucible 8 that can sealing by fusing.Outer crucible 8 can be quartz crucible.Preferably, its SiO
2content be not less than 99.99%.Outer crucible 8 can be sealed bottom, open-topped structure.Preferably, inner crucible 7,7A, 7B can put into, take out from the open top of outer crucible 8.Ectonexine crucible can share or not share same crucible bottom surface.Outer crucible 8 is longer than inner crucible 7,7A, 7B.Again, the open top of outer crucible 8 can sealing by fusing.Outer like this crucible 8 can surround inner crucible 7,7A, 7B completely after sealing by fusing, thereby grows the vacuum environment of sealing is provided for the crystal in inner crucible 7,7A, 7B.In addition, spacing between the inwall of the outer wall of inner crucible 7,7A, 7B and outer crucible 8 is preferably and is not less than 0.6mm, be preferably 0.6～1mm, can be easy to like this put into, take out inner crucible 7,7A, 7B, and provide space for the thermal expansion of inner crucible 7,7A, 7B.The shape of outer crucible 8 is not limit, as long as can place inner crucible 7,7A, 7B and it is surrounded completely, for example, can be the shapes such as right cylinder, round platform, circular cone, rectangular parallelepiped, prismoid shaped or prism.
< crystal growth >
In the present invention, can adopt above-mentioned nested type crucible to carry out crystal growth.Particularly, as example, crystal growth can comprise the following steps.
1) charging: the inner crucible that crystal growth raw material is packed into nested type crucible.In the time that crystal to be prepared is non-doping strontium iodide crystal, can select high-purity strontium iodide (for example purity is more than 99.99%) is raw material.In the time that crystal to be prepared is doping strontium iodide crystal, can select high-purity strontium iodide (for example purity is more than 99.99%) and high-purity doping agent (for example purity is more than 99.99%) is raw material.The doping agent adopting can be Eu
2+, Eu
3+, Tl
+, Pb
2+, Yb
2+and Yb
3+isoionic iodide, bromide, muriate or fluorochemical etc.Doping content can be 0～10at%, and best doping content is relevant with doping ionic species.Charging process preferably completes in not higher than 5% environment in humidity.For example can carry out in all not higher than the inert-atmosphere glove box of 1000ppm in water and oxygen level.In addition, can before charging, put into seed crystal to inoculate growth in inner crucible bottom as required.Orientable or the non-directional of seed crystal.For example can select the seed crystal of [010], [100], [001] and any direction to inoculate growth.Again, also can not put into seed crystal, and adopt the spontaneous superseded growth of special-shaped crucible, may be variant on the crystal mass now growing.The size and shape of inner crucible can be selected by the shape of required growing crystal, size.Again, can select multiple nested type crucibles, with the SrI of the different shapes of growing (as cylindrical, rectangle etc.), different size and heterogeneity simultaneously simultaneously
2crystal.
2) raw materials pretreatment: under certain temperature schedule and vacuum tightness, the raw material packing into is carried out to heat pre-treatment.For example, keep external crucible vacuumize make vacuum tightness not higher than 0.1Pa, be preferably 10
-3under state below Pa, by heating raw materials to 300～450 ℃, and be incubated 2～20 hours, to remove water possible in raw material and fugitive constituent.
3) crucible sealing by fusing: keep step 2) in the state that vacuumizes, the nested type crucible that fills pretreated raw material is reduced to room temperature, the outer crucible of sealing by fusing.For example can adopt oxyhydrogen flame welding torch to carry out sealing by fusing.Like this, can make following crystal growing process carry out in airtight vacuum environment.
4) crystal growth: nested type crucible after sealing by fusing is inserted to crucible degrowth stove, start intensification, insulation and melt raw material, control certain furnace temperature and temperature gradient of solid-liquid interface, make crucible pass through temperature gradient zone with certain fall off rate, carry out crystal growth.For example, specifically can adopt following steps: first by Control for Kiln Temperature within the scope of 550～700 ℃, be incubated 2～10 hours, melt all raw materials, use can also be by the melting of seed crystal top when seed crystal; Growth interface thermograde is controlled at 10～60 ℃/cm, preferably 30～40 ℃/cm, with the speed decline crucible of 0.1～5.0mm/ hour (being preferably 0.2～2mm/ hour) make raw material by temperature gradient zone with growing crystal; After all raw materials are all by temperature gradient zone, stop crucible and decline, growth finishes.After growth finishes, temperature control is reduced to 50～100 ℃, crystal and crucible are annealed 1～20 hour in position; Then, cool to 100 ℃ with the speed of 10～50 ℃/h (preferably 10～20 ℃/h), close growth furnace power supply, naturally cool to room temperature.The strontium iodide crystal that growth obtains can take out in inert atmosphere.Can, first by outer crucible opening or the destruction of nested type crucible, take out inner crucible, peel off inner crucible, can obtain strontium iodide crystal.
Advantage of the present invention is: the use of metal matrix/quartzy nested type crucible, both avoided component volatilization, suppress again reacting of melt and quartz crucible, the size and dimension that grows crystal is easily controlled, crystal stress is little, not easy to crack, and the perfection of crystal growing is good, the yield rate of growth is high, is suitable for suitability for industrialized production.Carbon back/quartzy nested type crucible combine carbon back easily design eliminate structure, eliminate success ratio high, not with the advantage of fusant reaction, and the feature of the easy sealing by fusing of quartz crucible, in the crucible decline stove of crystal growing process under can be under air atmosphere, complete, avoid the use of huge high vacuum growth apparatus, the volatilization of melt has obtained farthest restriction, have simple in structurely, be easy to mass and industrialized feature.
Further exemplify embodiment below to describe the present invention in detail.Should understand equally; following examples are only used to further illustrate the present invention; can not be interpreted as limiting the scope of the invention, some nonessential improvement that those skilled in the art's foregoing according to the present invention is made and adjustment all belong to protection scope of the present invention.The processing parameter that following example is concrete etc. is only also an example in OK range, and those skilled in the art can be done in suitable scope and be selected by explanation herein, and do not really want to be defined in the below concrete numerical value of example.
Adopt platinum/quartzy nested type crucible, the pure SrI of spontaneous superseded growth
2the concrete technology step of crystal is:
1) make capillary platinum crucible, platinum crucible internal diameter is 25mm, platinum crucible thickness is 0.1mm, platinum crucible bottom is the capillary structure with spontaneous superseded function, and capillary part internal diameter is 2-3mm, and length is 40mm, platinum crucible overall length is 200mm, it is 30mm quartz crucible that above-mentioned platinum crucible is placed in to internal diameter, in the tubular quartz crucible that length is 320mm, forms platinum/quartzy nested type crucible;
2), in nitrogen inert-atmosphere glove box, 200g strontium iodide raw material (purity is not less than 99.99%) is packed in quartz/platinum nested type crucible (as shown in Figure 2);
3) the nested type crucible that strontium iodide raw material is housed is taken out from glove box, outer quartz crucible is vacuumized, and the temperature to 450 ℃ that raises gradually, and keep 10h with water possible in removing raw material and fugitive constituent in this temperature, in above-mentioned intensification and insulating process, in crucible, vacuum tightness remains at below 0.01Pa;
4) state that maintenance vacuumizes quartz crucible, uses oxyhydrogen flame welding torch by outer quartz crucible sealing by fusing;
5) in the single crystal growing furnace of structure as shown in Figure 1, the bottom of quartz/platinum nested type crucible good sealing by fusing is placed in to diagram middle and upper part, growth furnace temperature gradient zone, temperature control is 600 ℃, make all meltings of raw material (comprising capillary end) in crucible, the gradient of solid-liquid interface temperature maintains 40 ± 2 ℃/cm left and right, with 0.6mm/h speed decline crucible, after all raw materials are all by temperature gradient zone, stop crucible and decline, growth finishes;
6) temperature control is down to 450 ℃, and keeps this temperature 10h to carry out in-situ annealing to crystal, then drop to 100 ℃ with the speed of 30 ℃/h, then close heating power supply, make natural crystal be cooled to room temperature;
7) in the glove box of nitrogen atmosphere, the outer quartz crucible of nested type crucible is destroyed, take out internal layer platinum crucible, peel off platinum crucible, obtain diameter and reach the non-doping strontium iodide crystal of 25mm.
Adopt seed crystal inoculating process, SrI grows in platinum/stone nested type crucible
2: the processing step of Eu crystal is:
1) by the SrI of 250g
2the EuI of (purity is not less than 99.99%) and 8.913g
2(purity is not less than 99.9%) powder is as raw material, and in water and oxygen level, all in the inert-atmosphere glove box lower than 100ppm, the raw material that proportioning is good mixes;
2) in above-mentioned glove box, be 10mm the diameter processing, the strontium iodide seed crystal that length is 60mm is placed in the bottom of making platinum crucible, and seed crystal is fixed, and then in quartz crucible, puts into mixed raw material M1, as shown in Figure 3;
3) platinum crucible that installs raw material is put into quartz glass tube, nested type crucible is taken out from glove box, will after heating raw materials, carry out pre-treatment, in treating processes, make the interior vacuum keep of crucible below 0.01Pa;
4) in the crucible decline stove shown in Fig. 1, temperature control is at 650 ℃, and rising platinum/quartzy nested type crucible makes the melting of seed crystal top section, and growth interface thermograde maintains 35 ℃/cm left and right, with 0.2mm/h speed decline crucible, until melt is all by temperature gradient zone crystallization;
5) after growth finishes, temperature control is reduced to 500 ℃, insulation 10h, carries out in-situ annealing processing to crystal, then drops to 100 ℃ with the speed of 30 ℃/h, then closes heating, is naturally cooled to room temperature;
6) in glove box, outer quartz crucible is destroyed, take out the platinum crucible of internal layer, and then peel off platinum crucible, take out complete SrI
2: 3at%Eu crystal.
Adopt graphite/quartz crucible pure SrI that grows
2the concrete technology step of crystal is:
1) make graphite/quartzy nested type crucible as shown in Figure 4, wherein plumbago crucible has the superseded structure design of combined type;
2) in above-mentioned graphite/quartzy nested type crucible, progressively add strontium iodide (purity is 99.99%) the raw material M2 of 100g, vacuumize and thermal treatment, keeping vacuum tightness to be better than under the state of 0.01Pa, progressively be warmed up to 400 ℃, then constant temperature more than at least 2 hours, still keeps the vacuum tightness of be better than≤0.01Pa in thermostatic process, stops afterwards thermal treatment and drops to room temperature in situation about keeping the vacuum constant;
3), by the outer quartz crucible sealing by fusing of graphite/quartzy nested type crucible, in sealing by fusing process, make in crucible vacuum keep at≤0.1Pa;
4) in the crucible decline stove shown in Fig. 1, temperature control is at 650 ℃, and rising quartz/graphite nested type crucible makes the melting of seed crystal top section, and growth interface thermograde maintains 35 ℃/cm left and right, with 0.5mm/h speed decline crucible, until melt is all by temperature gradient zone crystallization;
5) after growth finishes, temperature control is reduced to 500 ℃, insulation 10h, carries out in-situ annealing processing to crystal, then drops to 100 ℃ with the speed of 30 ℃/h, then closes heating, is naturally cooled to room temperature;
6) in glove box, outer quartz crucible is destroyed, take out the platinum crucible of internal layer, and then peel off platinum crucible, take out complete non-doping SrI
2crystal.
For ease of fully understanding the present invention, example has provided some concrete ins and outs and processes in setting forth in the above, but the present invention can also adopt other alternate manner that is different from this description to implement, those skilled in the art can do similar expansion without prejudice to intension of the present invention in the situation that.In the time setting forth the embodiment of the present invention, for ease of explanation, the description of process and details is carried out in conjunction with embodiment crucible structure figure, but in the actual fabrication process of crucible, its geometrical dimension and shape can freely change according to actual needs.
Industrial applicability: the invention provides a kind of method of nested type crucible growth strontium iodide crystal of simple to operate, with low cost, applicable mass, can realize this crystal-like suitability for industrialized production.The non-doping that the present invention is prepared and doping strontium iodide scintillation crystal are applicable to the fields such as Security Inspection Equipments, nuclear medicine and radiation detection.
Claims (11)
1. the nested type crucible for the strontium iodide crystal of growing, it is characterized in that, comprise inner crucible for holding crystal growth raw material and for the outer crucible of vacuum-pumping of sealed environment is provided, wherein said outer crucible is quartz crucible, and described inner crucible is metal matrix crucible or carbon back crucible;
Described outer crucible is longer than described inner crucible, can surround described inner crucible completely after sealing by fusing;
Spacing between the outer wall of described inner crucible and the inwall of described outer crucible is not less than 0.6mm.
2. the nested type crucible for the strontium iodide crystal of growing according to claim 1, is characterized in that, the bottom of described inner crucible is formed as having the structure of spontaneous superseded function.
3. the nested type crucible for the strontium iodide crystal of growing according to claim 1 and 2, is characterized in that the SiO of described quartz crucible
2content be not less than 99.99%.
4. according to the nested type crucible for the strontium iodide crystal of growing described in any one in claims 1 to 3, it is characterized in that, the material of described metal matrix crucible is any one metal in aluminium, platinum, iridium, tungsten and molybdenum or the alloy of any two or more metals.
5. according to the nested type crucible for the strontium iodide crystal of growing described in any one in claims 1 to 3, it is characterized in that, described carbon back crucible is plumbago crucible or vitreous carbon crucible.
6. the grow method of strontium iodide crystal, is characterized in that, comprising:
(1) the crystal growth raw material that contains high-purity strontium iodide and high-purity doping agent is packed into according in the inner crucible of the nested type crucible described in any one in claim 1 to 7 in not higher than 5% environment in humidity;
(2) under vacuum condition, described crystal growth raw material is heated to 300～450 ℃, and is incubated 2～20 hours and carries out pre-treatment;
(3) keeping, under the state vacuumizing, the nested type crucible that fills pretreated raw material is cooled to room temperature, the outer crucible of sealing by fusing; And
(4) the nested type crucible after sealing by fusing is inserted to crucible degrowth stove, carry out crystal growth by falling crucible method.
7. the method for growth strontium iodide crystal according to claim 6, is characterized in that, in step (1), described humidity is not or not water and oxygen level be not all higher than the inert ambient environment of 1000ppm higher than 5% environment.
8. according to the method for the growth strontium iodide crystal described in claim 6 or 7, it is characterized in that, in step (2), described vacuum condition be vacuum tightness not higher than 0.1Pa, be preferably 10
-3below Pa.
9. according to the method for the growth strontium iodide crystal described in any one in claim 6 to 8, it is characterized in that, can adopt Eu
2+, Eu
3+, Tl
+, Pb
2+, Yb
2+and Yb
3+isoionic iodide, bromide, muriate or fluorochemical etc. are as doping agent, and doping content can be 0～10at%, and best doping content is relevant with doping ionic species; Also can not adopt doping agent, the strontium iodide crystal of the non-doping of growing.
10. according to the method for the growth strontium iodide crystal described in any one in claim 6 to 9, it is characterized in that, in step (4), described crystal growth comprises the following steps:
At 2～10 hours fusing crystal growth raw materials of 550～700 ℃ of insulations;
Control growth interface thermograde at 10～60 ℃/cm, carry out crystal growth with the speed decline crucible of 0.1～5.0mm/ hour;
Crystal growth finishes rear furnace temperature and reduces by 50～100 ℃, and crystal and crucible are annealed 1～20 hour in position; And
After cooling to 100 ℃ with the speed of 10～50 ℃/h, naturally cool to room temperature.
11. according to the method for the growth strontium iodide crystal described in any one in claim 6 to 10, it is characterized in that, in crystal growth, can use seed crystal to inoculate growth, also can adopt spontaneous nucleation growth.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108560044A (en) * | 2018-06-01 | 2018-09-21 | 中国科学院理化技术研究所 | For CsB4O6Double-layer crucible for F crystal growth and CsB4O6F crystal growth method |
| CN109402724A (en) * | 2017-08-16 | 2019-03-01 | 中国科学院上海硅酸盐研究所 | The undoped and Eu of one kind2+Adulterate the orientation growing by zone melting device and method of iodate strontium crystal |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000247778A (en) * | 1999-02-25 | 2000-09-12 | Toshiba Ceramics Co Ltd | Quartz glass crucible, its production and pulling up of silicon single crystal using the same |
| CN201428006Y (en) * | 2009-04-08 | 2010-03-24 | 北京滨松光子技术股份有限公司 | Vacuum quartz crucible used for growth of single crystals by descent method |
| CN101982568A (en) * | 2010-09-27 | 2011-03-02 | 中国计量学院 | Method for growing strontium iodide scintillating crystals by nonvacuum crucible descent method |
| CN102899714A (en) * | 2012-09-25 | 2013-01-30 | 四川大学 | Growth process and growth container of phosphorus-silicon-cadmium single crystal |
-
2014
- 2014-02-17 CN CN201410053534.0A patent/CN103789832B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000247778A (en) * | 1999-02-25 | 2000-09-12 | Toshiba Ceramics Co Ltd | Quartz glass crucible, its production and pulling up of silicon single crystal using the same |
| CN201428006Y (en) * | 2009-04-08 | 2010-03-24 | 北京滨松光子技术股份有限公司 | Vacuum quartz crucible used for growth of single crystals by descent method |
| CN101982568A (en) * | 2010-09-27 | 2011-03-02 | 中国计量学院 | Method for growing strontium iodide scintillating crystals by nonvacuum crucible descent method |
| CN102899714A (en) * | 2012-09-25 | 2013-01-30 | 四川大学 | Growth process and growth container of phosphorus-silicon-cadmium single crystal |
Non-Patent Citations (1)
| Title |
|---|
| 张烨: "掺铕碘化锶晶体的制备及闪烁性能的研究", 《中国优秀硕士论文全文数据库（工程科技I辑）》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109402724A (en) * | 2017-08-16 | 2019-03-01 | 中国科学院上海硅酸盐研究所 | The undoped and Eu of one kind2+Adulterate the orientation growing by zone melting device and method of iodate strontium crystal |
| CN109402724B (en) * | 2017-08-16 | 2020-12-11 | 中国科学院上海硅酸盐研究所 | Non-doped and Eu2+Directional zone-melting growth device and method for doped strontium iodide crystal |
| CN108560044A (en) * | 2018-06-01 | 2018-09-21 | 中国科学院理化技术研究所 | For CsB4O6Double-layer crucible for F crystal growth and CsB4O6F crystal growth method |
| CN114959873A (en) * | 2018-06-01 | 2022-08-30 | 中国科学院理化技术研究所 | For CsB 4 O 6 Double-layer crucible for F crystal growth and CsB 4 O 6 F crystal growth method |
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