CN221028761U - Crystal growth apparatus - Google Patents

Abstract

The application discloses a crystal growth device, and relates to the technical field of crystal growth. The crystal growing device comprises a furnace body, a supporting component, a lifting driving mechanism and a cooling ring. The furnace body forms the furnace chamber, and the inboard of furnace body is provided with heating element. The supporting component comprises an objective table and a supporting shaft, wherein the objective table is positioned in the furnace chamber and is used for placing the crucible. The lifting driving mechanism is used for driving the furnace body and/or the supporting component so as to enable the furnace body to lift relative to the supporting component. The cooling ring is arranged in the furnace chamber, a cooling channel for the flow of a refrigerant is formed in the cooling ring, and the cooling ring is communicated with the outside of the furnace body through a first pipeline and a second pipeline. The crystal growth device can effectively control the temperature field in the furnace chamber through the cooling ring, provide proper temperature gradient for crystal growth, and ensure the crystal growth quality. Therefore, the crystal growth apparatus provided by the application is beneficial to preparing large-size crystals.

Description

Crystal growth apparatus

Technical Field

The application relates to the technical field of crystal growth, in particular to a crystal growth device.

Background

In the process of preparing large-size crystals, the single crystal growth device adopting the descent method needs to form a temperature field with a certain temperature gradient in the device, then slowly descends a crucible containing raw material melt, and moves from a high-temperature area to a low-temperature area to realize crystallization. The temperature gradient of crystallization is closely related to the crystallization quality, and if the temperature gradient is unsuitable or the phenomenon of growth acceleration occurs, the phenomenon of excessive inclusion, poor impurity removal and the like of the crystals easily occur. However, the existing crystal growth apparatus has poor control effect on temperature gradient, resulting in poor crystal growth quality and high difficulty in preparing large-size crystals.

In view of this, the present application has been made.

Disclosure of utility model

The application aims to provide a crystal growth device which can effectively control the temperature gradient of crystal growth, improve the crystal growth quality and is beneficial to preparing large-size crystals.

Embodiments of the present application are implemented as follows:

the present application provides a crystal growth apparatus comprising:

The furnace body forms a furnace chamber, and a heating component is arranged on the inner side of the furnace body;

The support assembly comprises an objective table and a support shaft, the objective table is positioned in the furnace chamber and used for placing the crucible, one end of the support shaft is connected to the bottom of the objective table, and the other end of the support shaft extends out of the furnace chamber from the lower end of the furnace body;

The lifting driving mechanism is used for driving the furnace body and/or the supporting component so as to enable the furnace body to lift relative to the supporting component;

The cooling ring is arranged in the furnace chamber, a through hole is formed in the middle of the cooling ring and used for allowing the object stage and the supporting shaft to pass through, a cooling channel for cooling medium to flow is formed inside the cooling ring, and the cooling ring is communicated with the outside of the furnace body through a first pipeline and a second pipeline.

In an alternative embodiment, the crystal growing apparatus includes a cold source connected to the first conduit.

In an alternative embodiment, the cold source is connected to the cooling circuit via a first line, a second line and a cooling ring.

In an alternative embodiment, the refrigerant is water and the cold source comprises a chiller.

In an alternative embodiment, the heating assembly comprises a first heating assembly and a second heating assembly, the first heating assembly being disposed above the second heating assembly at intervals, and the cooling ring being disposed between the first heating assembly and the second heating assembly.

In an alternative embodiment, be provided with first heat preservation spare in the furnace body, the inner wall of furnace chamber is located to first heat preservation spare is protruding to extend along the circumference of furnace chamber and form the cyclic annular, the middle part of first heat preservation spare forms the through-hole that supplies objective table and back shaft to pass, first heat preservation spare is located between first heating element and the second heating element in vertical direction, the cooling ring is located first heating element's lower extreme, first heat preservation spare is located second heating element's upper end, the cooling ring sets up in first heat preservation spare top with the interval.

In an alternative embodiment, a second heat-insulating member is arranged in the furnace body, the second heat-insulating member is convexly arranged on the inner wall of the furnace chamber and extends along the circumferential direction of the furnace chamber to form a ring shape, a through hole for the object stage and the supporting shaft to pass through is formed in the middle of the second heat-insulating member, and the second heat-insulating member is arranged below the second heating component.

In an alternative embodiment, the aperture of the through hole of the second insulating member is adjustable.

In an alternative embodiment, the furnace body is provided with a plurality of thermocouples for detecting the temperature in the furnace chamber.

In an alternative embodiment, the crystal growing apparatus further comprises a rotary driving mechanism, and the rotary driving mechanism is in transmission connection with the support shaft and is used for driving the support shaft to rotate.

The embodiment of the application has the beneficial effects that:

The crystal growth device provided by the application comprises a furnace body, a supporting component, a lifting driving mechanism and a cooling ring. The furnace body forms the furnace chamber, and the inboard of furnace body is provided with heating element. The support assembly comprises an objective table and a support shaft, wherein the objective table is positioned in the furnace chamber and used for placing the crucible, one end of the support shaft is connected to the bottom of the objective table, and the other end of the support shaft extends out of the furnace chamber from the lower end of the furnace body. The lifting driving mechanism is used for driving the furnace body and/or the supporting component so as to enable the furnace body to lift relative to the supporting component. The cooling ring is arranged in the furnace chamber, a through hole is formed in the middle of the cooling ring and used for allowing the object stage and the supporting shaft to pass through, a cooling channel for cooling medium to flow is formed inside the cooling ring, and the cooling ring is communicated with the outside of the furnace body through a first pipeline and a second pipeline. The cooling medium can be introduced into the cooling ring through the first pipeline, and the cooling medium is sent out of the furnace body from the second pipeline after taking heat away, so that a temperature field with a certain temperature gradient can be formed in the furnace chamber, and the temperature gradient can be controlled by controlling the flow of the cooling medium. The crystal growth device can effectively control the temperature field in the furnace chamber and provide proper temperature gradient for crystal growth, so that the crystallization speed is not too high, the crystallization speed is kept in a reasonable interval, impurities are favorably discharged to the top of the crystal, and the crystal growth quality is ensured. Therefore, the crystal growth apparatus provided by the application is beneficial to preparing large-size crystals.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a crystal growing apparatus according to an embodiment of the present application;

Fig. 2 is a cross-sectional view of a crystal growing apparatus in one embodiment of the application.

010-Crystal growth apparatus; 110-upper furnace body; 111-a first heating assembly; 120-lower furnace body; 121-a second heating assembly; 131-high temperature monitoring thermocouple; 132-a high temperature control thermocouple; 133-a first crystallization monitoring thermocouple; 134-a second crystallization monitoring thermocouple; 135-annealing monitoring thermocouple; 136-annealing a temperature-controlled thermocouple; 140-cooling ring; 141-a first line; 142-a second line; 150-a first thermal insulation member; 160-a second insulating member; 200-a support assembly; 210-stage; 220-supporting shaft; 230-a rotary drive mechanism; 300-lifting driving mechanism; 310-driving member; 320-a transmission assembly; 020-crucible.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the application, as presented in the figures, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

In the process of crystal growth, if the growth temperature gradient is unsuitable or the growth acceleration phenomenon occurs, the phenomenon of excessive inclusion, poor impurity removal and the like of the crystal easily occurs. However, the temperature gradient of the crystal growth cannot be well controlled by the descent method single crystal growth device in the prior art, so that the purity requirement on raw materials is often high, too many impurities cannot be contained, and the cost is high. In the middle and later stages of the preparation, large-size single crystals tend to have a smaller gradient of crystals due to an increase in heat conduction of the crystals themselves, and even supercooling, thereby causing growth acceleration. Therefore, it is difficult to prepare high-quality large-sized single crystals by the existing apparatus and method.

In order to improve the defects of the prior art, the embodiment of the application provides a crystal growth device, which can take away heat in a furnace chamber by using a cooling ring to form a proper temperature gradient by using a cooling medium, thereby providing a good temperature field for crystal growth, improving the crystal growth quality and providing good conditions for manufacturing large-size crystals.

FIG. 1 is a schematic diagram of a crystal growing apparatus 010 according to an embodiment of the present application; fig. 2 is a cross-sectional view of a crystal growing apparatus 010 in an embodiment of the application. As shown in fig. 1 and 2, the crystal growing apparatus 010 according to the embodiment of the present application includes a furnace body, a supporting assembly 200, a lifting driving mechanism 300, and a cooling ring 140. The furnace body forms a furnace chamber, and a heating component is arranged on the inner side of the furnace body; the support assembly 200 includes a stage 210 and a support shaft 220, the stage 210 is disposed in the furnace chamber for placing the crucible 020, one end of the support shaft 220 is connected to the bottom of the stage 210, and the other end extends out of the furnace chamber from the lower end of the furnace body. The lifting drive mechanism 300 is used to drive the furnace body and/or the support assembly 200 to lift the furnace body relative to the support assembly 200. The cooling ring 140 is located in the furnace chamber, a through hole is formed in the middle of the cooling ring 140 for the stage 210 and the support shaft 220 to pass through, a cooling channel for the flow of the cooling medium is formed inside the cooling ring 140, and the cooling ring 140 is communicated with the outside of the furnace body through a first pipeline and a second pipeline.

In this embodiment, the furnace body includes an upper furnace body 110 and a lower furnace body 120, and the upper furnace body 110 and the lower furnace body 120 are axially communicated to form a furnace chamber together. The bottom end of the lower furnace body 120 forms an opening from which the lower end of the support shaft 220 protrudes. The upper and lower bodies 110 and 120 each include a heat insulating material therein so that the temperature inside the cavity can be maintained.

In this embodiment, the heating assembly includes a first heating assembly 111 and a second heating assembly 121, and the first heating assembly 111 is disposed above the second heating assembly 121 at intervals. The first heating assembly 111 and the second heating assembly 121 each include a plurality of heating elements arranged at intervals in the circumferential direction, so that a uniform temperature field in the circumferential direction can be created. The heating elements included in the first heating element 111 and the second heating element 121 may be induction coils or resistance wires.

Alternatively, the cooling ring 140 is located between the first heating assembly 111 and the second heating assembly 121 in the vertical direction. The cooling ring may be annular with its central axis coinciding with the central axis of the cavity. Specifically, the cooling ring 140 is provided at the lower end of the first heating member 111, and the raw material in the crucible 020 is heated to a molten state by the first heating member 111, and crystallization is started when the raw material melt in the crucible 020 falls to the vicinity of the cooling ring 140. The first pipeline 141 can continuously provide the cooling ring 140 with the cooling medium, and the cooling medium absorbs the heat in the furnace chamber and then flows out of the furnace chamber through the second pipeline 142. By controlling the flow of the cooling medium, the temperature near the cooling ring 140 in the furnace chamber can be controlled, and a proper temperature field is constructed for crystallization. The refrigerant may be gas or liquid, for example, nitrogen, air, water or oil.

Optionally, the crystal growing apparatus 010 further includes a cold source (not shown) connected to the first pipe, so that the cooling medium can be continuously supplied into the cooling ring 140 through the first pipe. Optionally, the cold source and the cooling ring form a cooling loop through the first pipeline and the second pipeline. The cold source may be a device that provides cold water, such as a chiller. In one embodiment, the cooling loop is formed by the first pipeline 141, the cooling ring 140 and the second pipeline 142, the cooling loop cools water and pumps the cooled water to the cooling ring 140 through the first pipeline 141, the cooled water heats up after absorbing heat, and then returns to the cooling loop through the second pipeline 142, and the cooled water is pumped to the cooling ring 140 again after being cooled, so that the circulation of the refrigerant is formed. By adjusting the cooling power of the chiller and the circulation rate of the coolant, the efficiency of the cooling loop 140 to absorb heat can be adjusted, thereby adjusting the temperature field and thus the temperature gradient of the crystals.

In alternative embodiments, the cold source may be only connected to the first pipeline 141, and the refrigerant may be directly released through the second pipeline 142 after absorbing heat through the cooling ring 140, so that the cooling circuit may not be formed. The cold source may be a tap, which is communicated with only the first pipe 141, and the cooling intensity of the cooling ring 140 is adjusted by adjusting the opening degree of the tap.

In alternative embodiments, the cooling ring 140 may also be configured to be adjustable in position up and down, such as by a motor and associated gearing structure.

Further, a first heat preservation member 150 is disposed in the furnace body, and the first heat preservation member 150 is protruding on the inner wall of the furnace chamber and extends along the circumferential direction of the furnace chamber to form a ring shape. A through hole through which the stage 210 and the support shaft 220 pass is formed in the middle of the first heat insulating member 150, and the first heat insulating member 150 is located between the first heating assembly 111 and the second heating assembly 121 in the vertical direction. The central axis of the first heat insulating member 150 coincides with the central axis of the cavity. In the present embodiment, the first heat preservation member 150 is located at the upper end of the second heating element 121, and the cooling ring 140 is disposed above the first heat preservation member 150 at intervals.

It can be seen that the cooling ring 140 and the first heat retainer 150 divide the cavity into three general areas, and the area above the cooling ring 140 is a high temperature area, and the temperature is controlled by the first heating assembly 111. The region between the cooling ring 140 and the first heat retainer 150 is a transition region that is at a temperature lower than the high temperature region, and typically where the molten feedstock begins to crystallize after entering the region. Below the first thermal insulating member 150 is an annealing zone whose temperature is controlled by the second heating member 121 for annealing the crystal to relieve internal stress of the crystal. The transition zone and the annealing zone are relatively low in temperature compared to the high temperature zone.

Further, a second heat-insulating member 160 is disposed in the furnace body, the second heat-insulating member 160 is convexly disposed on the inner wall of the furnace chamber and extends along the circumferential direction of the furnace chamber to form a ring shape, a through hole for passing the stage 210 and the supporting shaft 220 is formed in the middle of the second heat-insulating member 160, and the second heat-insulating member 160 is disposed below the second heating assembly 121. The annealing zone is located between the first insulating member 150 and the second insulating member 160. Optionally, a second insulating member 160 is disposed at the opening of the lower furnace 120.

In this embodiment, the aperture of the through hole of the second insulating member 160 is adjustable. Because the lower end of the through hole of the second heat insulating member 160 is communicated with the external environment, the temperature field of the annealing zone can be adjusted to a certain extent by adjusting the caliber of the second heat insulating member 160, thereby controlling the annealing process. The smaller caliber can reduce the convection of the external air and the air in the furnace, thereby being beneficial to improving the annealing temperature; the larger caliber can facilitate the taking out of the crucible 020.

Both the first insulating member 150 and the second insulating member 160 may be made of insulating bricks. The second insulating member 160 may be formed of a plurality of parts separately so as to realize an adjustable caliber. For example, the second thermal insulating member 160 is designed in a diaphragm-like multi-piece structure.

In the embodiment of the application, the furnace body is provided with a plurality of thermocouples for detecting the temperature in the furnace chamber.

Specifically, the several thermocouples include, from top to bottom, a high temperature monitoring thermocouple 131, a high temperature control thermocouple 132, a first crystallization monitoring thermocouple 133, a second crystallization monitoring thermocouple 134, an annealing monitoring thermocouple 135, and an annealing control thermocouple 136. In this embodiment, the high temperature control thermocouple 132 is disposed at the middle position of the high temperature region, and the set target temperature of the high temperature region is compared with the detected temperature of the high temperature control thermocouple 132, so as to control the first heating component 111 to regulate and control the temperature of the high temperature region; in other words, whether the high temperature region reaches the target temperature is determined according to the temperature fed back by the high temperature thermocouple 132. The first crystallization monitoring thermocouple 133 and the second crystallization monitoring thermocouple 134 are respectively disposed at upper and lower sides of the cooling ring 140 for monitoring the crystallization temperature condition because the melt starts to crystallize in the vicinity of the cooling ring 140. The second heating assembly 121 is controlled to regulate and control the temperature of the annealing zone by comparing the set target temperature of the annealing zone with the detected temperature of the annealing temperature control thermocouple 136; in other words, whether the annealing zone reaches the target temperature is determined based on the temperature fed back by the annealing temperature thermocouple 136. An annealing monitoring thermocouple 135 is provided at the lower side of the second heating assembly 121. The temperature of different positions of the whole furnace chamber is detected by each thermocouple, so that the temperature field of the furnace chamber can be effectively monitored.

In this embodiment, the lifting driving mechanism 300 is in transmission connection with the furnace body, and is used for driving the furnace body to lift relative to the supporting component 200. By driving the furnace to move, the crucible 020 on the stage 210 can be brought into a more stable state, thereby ensuring better crystallization. In alternative embodiments, the lifting drive mechanism 300 may be in driving connection with the support assembly 200, while the furnace body is stationary, and the crucible 020 is lifted relative to the furnace body by driving the support assembly 200 up and down.

Alternatively, the lifting drive mechanism 300 comprises a drive member 310 and a transmission assembly 320, the transmission assembly 320 drivingly connecting the drive member 310 to the furnace body. The driver 310 may be a motor, such as a stepper motor. The drive assembly 320 may include a screw-nut assembly to effect lifting of the furnace body.

Further, the crystal growing apparatus 010 further includes a rotation driving mechanism 230, and the rotation driving mechanism 230 is in transmission connection with the support shaft 220 for driving the support shaft 220 to rotate. The crucible 020 is driven to rotate by the bearing table before crystallization, so that the raw materials are fully melted, and impurities are more effectively distributed on the surface of the crystal.

The application method of the crystal growth apparatus 010 provided by the embodiment of the application is as follows:

First, a seed crystal is placed in the bottom of a crucible 020, then a raw material is charged into the crucible 020, a lid plate is covered, and the crucible 020 is placed on a stage 210. The high temperature region is raised to a target temperature by the first heating assembly 111 according to the normal growth temperature of the crystal, so that the raw material is completely melted. In the early stage of crystal growth, the rotation driving mechanism 230 may be controlled to control the rotation speed of the crucible 020 to 0 to 30rpm, so that the raw material is sufficiently melted. When the crystal starts to grow, the rotation is stopped, and the crucible 020 is kept stable.

After the raw materials are sufficiently melted, the lifting driving mechanism 300 is controlled to drive the furnace body to move upwards slowly according to the set growth rate, at this time, the crucible 020 slowly descends relative to the furnace body, and the cooling ring 140 is continuously filled with the cooling medium. When the temperature field has proper temperature gradient, the top of the seed crystal and the melt slowly pass through the solid-liquid interface for inoculation by moving the furnace body upwards. By moving the furnace up, its melt is passed through cooling ring 140. The crystallization temperature can be monitored by the first crystallization monitor thermocouple 133 and the second crystallization monitor thermocouple 134, and a proper crystallization temperature gradient can be always formed by controlling the flow rate of the cooling medium of the cooling ring 140. The cooling ring 140 may also be suitably adjusted up and down as needed for the length of crystal growth.

When crucible 020 is brought below first insulating member 150, the crystal enters the annealing zone. Whether the temperature of the annealing zone is suitable for crystal annealing can be monitored by the annealing monitoring thermocouple 135, and the annealing temperature can be adjusted by the annealing control thermocouple 136 and the second heating member 121.

The second insulating member 160 can adjust the caliber according to the annealing temperature. Optionally, in the initial stage of lowering the crucible 020, the distance from the inner edge of the through hole of the second insulating member 160 to the support shaft 220 is smaller than 10mm, and after the annealing temperature reaches the set temperature, the distance from the inner edge of the through hole of the second insulating member 160 to the support shaft 220 is controlled to be 10-30 mm, and specifically, the distance can be adjusted according to the difference between the actual temperature and the annealing temperature.

Alternatively, according to the production requirement, the crystal growing apparatus 010 of the present application may be made into an array type multi-station for mass production.

The crystal growth apparatus 010 provided by the embodiment of the application can well meet the temperature gradient required by various crystals by adjusting the heat taken away by the cooling ring 140, so that the crystals with better quality can be prepared. By adjusting the cooling ring 140, the temperature gradient required for each stage of early, middle and late crystal growth can be effectively adjusted, and impurity removal can be effectively performed, so that large-sized crystals can be prepared.

The efficacy of the cooling ring 140 in the crystal growth apparatus 010 according to the embodiment of the present application is explained below by two test examples.

1. Take as an example the preparation of CNGS (Ca ₃NbGa₃Si₂O₁₄) crystals. The crucible 020 has a length of 300mm, the furnace chamber has a height of 400mm, the crystal growth length is 180mm, and the growth temperature is 1330 ℃ (namely, the high temperature control thermocouple 132 sets the temperature control temperature to 1387 ℃ so that the inoculation temperature is higher than the melting point by 50 ℃).

The data measured without the cooling ring 140 (replaced with insulating brick) are as follows:

In the crystallization stage, the temperature measured by the high temperature thermocouple 131 is 1487 ℃, the temperature measured by the first crystallization thermocouple 133 is 1380 ℃, and the temperature measured by the second crystallization thermocouple 134 is 1243 ℃.

When the crystal grows to 80mm, the temperature measured by the high temperature monitoring thermocouple 131 is 1492 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1367 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1252 ℃. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal grows to 130mm, the temperature measured by the high temperature monitoring thermocouple 131 is 1513 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1356 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1263 ℃. The crystals were observed with a laser, and the crystals appeared to be tiny bubbles starting at 116mm but were substantially distributed on the outer surface.

When the crystal grows to 180mm, the temperature measured by the high temperature monitoring thermocouple 131 is 1532 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1338 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1275 ℃. The macroscopic crystal is wrapped from 142mm to the center, and bubbles and internal impurities on the outer surface of the crystal are obvious.

The data measured after the cooling ring 140 is set up are as follows:

In the crystallization stage, the temperature measured by the high temperature monitoring thermocouple 131 is 1496 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1378 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1198 ℃.

When the crystal grows to 80mm, the temperature measured by the high temperature monitoring thermocouple 131 is 1515 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1376 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1196 ℃. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal was grown to 130mm, the temperature measured by the high temperature monitoring thermocouple 131 was 1573 ℃, the temperature of the first crystallization monitoring thermocouple 133 was 1374 ℃, and the temperature of the second crystallization monitoring thermocouple 134 was 1194 ℃. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal grows to 180mm, the temperature measured by the high temperature monitoring thermocouple 131 is 1631 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 1371 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 1191 ℃. The crystal was observed with a laser, and bubbles and impurities appeared from 167 mm.

2. Taking as an example the preparation of crystals of certain halide scintillation materials. The crucible 020 has a length of 300mm, a furnace chamber has a height of 400mm, a crystal growth length of 180mm, and a growth temperature 733 ℃ (Gao Wenkong thermocouple 132 is provided with a temperature control temperature of 780 ℃).

The measured data without the cooling ring 140 (replaced with insulating bricks) are as follows:

In the crystallization stage, the temperature measured by the high temperature monitoring thermocouple 131 is 865 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 772 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 618 ℃.

When the crystal grows to 80mm, the temperature measured by the high temperature monitoring thermocouple 131 is 876 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 765 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 624 ℃. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal grows to 130mm, the temperature measured by the high temperature monitoring thermocouple 131 is 891 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 753 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 633 ℃. The crystals were observed with a laser, and the crystals appeared as tiny bubbles starting from 123mm, but were substantially distributed on the outer surface.

When the crystal grows to 180mm, the temperature measured by the high temperature monitoring thermocouple 131 is 904 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 741 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 645 ℃. The impurities are slowly wrapped from 159mm of the macroscopic crystal to the center, and bubbles and internal impurities on the outer surface of the crystal are obvious.

The measured data after the cooling ring 140 is set up are as follows:

In the crystallization stage, the temperature measured by the high-temperature monitoring thermocouple 131 is 872 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 774 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 624 ℃.

When the crystal grows to 80mm, the temperature measured by the high temperature monitoring thermocouple 131 is 883 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 771 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 621 ℃. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal grows to 130mm, the temperature measured by the high temperature monitoring thermocouple 131 is 896 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 768 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 618 ℃. The crystal is macroscopically free from anomalies. The crystal has no abnormal condition in the macroscopic sense, is crystal clear, and has no light path when the interior of the crystal is observed by laser, so that the crystal has better impurity removing effect.

When the crystal grows to 180mm, the temperature measured by the high temperature monitoring thermocouple 131 is 913 ℃, the temperature of the first crystallization monitoring thermocouple 133 is 764 ℃, and the temperature of the second crystallization monitoring thermocouple 134 is 614 ℃. The crystal was observed with a laser, and bubbles and impurities appeared from the 171mm position.

As can be seen from the above two test examples, under the condition that the method of placing the insulating brick is used, the crystal is not changed much in the initial stage of growth, but as the crystal grows to 120mm, the impurity removal capacity of the crystal is poorer and poorer, and under the influence of factors such as poor heat conduction of the crystal, impurities on the surface of the crystal are more and more, so that the size of the prepared crystal is limited, and the large-size crystal with better quality cannot be prepared. In the case of using the cooling ring 140, the temperature gradient required by the crystal variety can be effectively adjusted by the cooling ring 140, so that the required temperature gradient can be achieved at the early, middle and later stages of crystal growth, thereby being beneficial to preparing single crystals with large size and good quality.

The above is only a preferred embodiment of the present application, and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A crystal growth apparatus, comprising:

The furnace comprises a furnace body, wherein the furnace body forms a furnace chamber, and a heating assembly is arranged on the inner side of the furnace body;

The support assembly comprises an objective table and a support shaft, the objective table is positioned in the furnace chamber and used for placing a crucible, one end of the support shaft is connected to the bottom of the objective table, and the other end of the support shaft extends out of the furnace chamber from the lower end of the furnace body;

The lifting driving mechanism is used for driving the furnace body and/or the supporting component so as to enable the furnace body to lift relative to the supporting component;

The cooling ring is arranged in the furnace chamber, a through hole is formed in the middle of the cooling ring and used for the objective table to pass through with the supporting shaft, a cooling channel for cooling medium to flow is formed inside the cooling ring, and the cooling ring is communicated with the outside of the furnace body through a first pipeline and a second pipeline.

2. The crystal growing apparatus of claim 1, wherein the crystal growing apparatus comprises a cold source connected to the first pipe.

3. The crystal growth apparatus of claim 2, wherein the cold source is coupled to the cooling loop via the first conduit, the second conduit, and the cooling loop.

4. The crystal growth apparatus of claim 3, wherein the cooling medium is water and the cold source comprises a chiller.

5. The crystal growth apparatus of claim 1, wherein the heating assembly comprises a first heating assembly and a second heating assembly, the first heating assembly being disposed above the second heating assembly at intervals, the cooling ring being disposed between the first heating assembly and the second heating assembly.

6. The crystal growth apparatus of claim 5, wherein a first heat retaining member is disposed in the furnace body, the first heat retaining member is disposed protruding on an inner wall of the furnace chamber and extends along a circumferential direction of the furnace chamber to form a ring shape, a through hole through which the stage and the support shaft pass is formed in a middle portion of the first heat retaining member, the first heat retaining member is disposed between the first heating assembly and the second heating assembly in a vertical direction, the cooling ring is disposed at a lower end of the first heating assembly, the first heat retaining member is disposed at an upper end of the second heating assembly, and the cooling ring is disposed above the first heat retaining member at intervals.

7. The crystal growth apparatus according to claim 6, wherein a second heat insulating member is provided in the furnace body, the second heat insulating member is provided protruding from an inner wall of the furnace chamber and extending in a circumferential direction of the furnace chamber to form a ring shape, a through hole through which the stage and the support shaft pass is formed in a middle portion of the second heat insulating member, and the second heat insulating member is provided below the second heating assembly.

8. The crystal growth apparatus of claim 7, wherein the aperture of the through-hole of the second insulating member is adjustable.

9. The crystal growing apparatus according to claim 1, wherein a plurality of thermocouples for detecting the temperature in the furnace chamber are provided on the furnace body.

10. The crystal growing apparatus of claim 1 further comprising a rotary drive mechanism drivingly connected to the support shaft for driving the support shaft in rotation.