Czochralski method small crystal growth device

Abstract

The utility model discloses a Czochralski method small-sized crystal growth device, which adopts a first sealing assembly and a second sealing assembly which are split, a crucible is arranged on the second sealing assembly, the second sealing assembly can be in butt joint with / separated from the first sealing assembly under the driving of a first linear module, and a heating furnace is arranged on the outer side of the first sealing assembly in a sleeving manner; after the second sealing assembly and the first sealing assembly are in butt joint, the first sealing assembly and the second sealing assembly are heated, crystal materials in the crucible are heated and melted, and the heating furnace can be driven by the second linear module to move in the axial direction of the first sealing assembly and the second sealing assembly. Therefore, the crystal material moves in the upward lifting process after growing, the change rate of the ambient temperature of the crystal material is reduced, the growth of the crystal is facilitated, and the rate of finished products is improved.

Description

Technical Field

[0001] The invention relates to the technical field of crystal growth equipment, in particular to a small crystal growth furnace, in particular to a small crystal growth device using a Czochralski method. Background Art

[0002] The Czochralski method is a common method for preparing artificial crystals. This method can be used to grow high-quality single crystal materials from the melt. This method has been applied to the growth of important artificial crystal materials such as sapphire single crystals, yttrium aluminum garnet single crystals, silicon germanium single crystals, and calcium fluoride single crystals. Compared with other crystal growth techniques, crystals grown by the Czochralski method have low dislocation density, high optical uniformity, and low internal stress.

[0003] The basic principle of the Czochralski method is to heat and melt the raw materials that make up the crystal in a crucible, connect a seed crystal to the surface of the melt and pull the melt. Under controlled conditions, the atoms or molecules of the seed crystal and the melt are constantly rearranged at the interface, and gradually solidify as the temperature drops to grow a single crystal. In the process of preparing crystals by the Czochralski method, the temperature of the area where the crystal is just formed in the crystal growth device is higher, while the temperature of the area near the inlet of the seed crystal rod is lower than that of the area where the crystal is formed. Due to the large temperature gradient, when the seed crystal rod pulls the crystal, the temperature around the crystal drops faster, and the crystal is prone to cracking, which is not conducive to the growth of the crystal and reduces the yield rate. Summary of the invention

[0004] In order to solve the technical problems existing in the background technology, the present invention proposes a small crystal growth device using the pulling method, in which a heating furnace is arranged to move along with the crystal material during the upward pulling process after the crystal material grows, thereby reducing the rate of change of the temperature around the crystal material, which is beneficial to the growth of the crystal and improves the yield rate.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A small crystal growth device using a Czochralski method, comprising: a furnace frame, a first sealing component fixedly mounted on the furnace frame in a vertical direction, a second sealing component located below the first sealing component and cooperating with the first sealing component, and a crucible fixedly mounted in the second sealing component for containing crystal materials;

[0007] The second sealing component is installed on the furnace frame through the first linear module, so as to move in the vertical direction under the drive of the first linear module and dock with / separate from the first sealing component;

[0008] A heating furnace is provided on the outside of the first sealing component to heat the first sealing component and the second sealing component after the second sealing component is docked with the first sealing component, so as to heat and melt the crystal material in the crucible. The heating furnace is installed on the furnace frame through the second linear module, so as to move along the axial direction of the first sealing component and the second sealing component under the drive of the second linear module, so as to reduce the rate of change of the temperature around the crystal material during the upward pulling process after the crystal material grows.

[0009] Furthermore, the first sealing component includes a quartz tube and a first flange connected to the bottom of the quartz tube, and the second sealing component includes a second flange adapted to the first flange, so that after the second sealing component is docked with the first sealing component, the second flange is connected and fixed to the first flange by bolts.

[0010] Furthermore, the quartz tube and the first flange are sealed and connected via a sealing ring, and the first flange and the second flange are sealed and connected via a sealing gasket and a clamp.

[0011] Furthermore, the second sealing component also includes a flange cover, the second sealing component is connected to the first linear module through the flange cover, and the crucible is fixedly mounted on the flange cover through a crucible support tube. The height of the crucible support tube is greater than the height of the second sealing component, so that after the second sealing component is docked with the first sealing component, the crucible can be fully extended into the first sealing component.

[0012] Furthermore, a thermocouple is installed in the crucible support tube to detect the temperature of the crucible in real time.

[0013] Furthermore, one side of the second sealing component is connected to the air inlet through a second branch pipe so that after the second sealing component is docked with the first sealing component, protective gas can be filled into the first sealing component and the second sealing component. The top of the first sealing component is connected to the air outlet through the first branch pipe, and solenoid valves are provided in the air inlet and the air outlet to control the balance of inlet and outlet gas and maintain a constant pressure state.

[0014] Furthermore, the top of the first sealing component is connected to a digital anti-corrosion vacuum gauge through a first branch pipe to detect and display the gas pressure in the first sealing component and the second sealing component in real time when the protective gas is filled into the first sealing component and the second sealing component.

[0015] Furthermore, the top of the first sealing component is connected to a mechanical pressure relief valve through a first branch pipe, so as to manually relieve pressure when the gas pressure in the first sealing component and the second sealing component exceeds a preset threshold.

[0016] Furthermore, one side of the second sealing component is connected to the vacuum port through a second branch pipe, so that the air inside the first sealing component and the second sealing component can be evacuated before the protective gas is filled into the first sealing component and the second sealing component.

[0017] Beneficial effects of the present invention: The small crystal growth device using the pulling method provided by the present invention adopts a split first sealing component and a second sealing component, and the crucible is arranged on the second sealing component, and the second sealing component can be connected / separated with the first sealing component under the drive of the first linear module, and a heating furnace is sleeved on the outer side of the first sealing component, and when the second sealing component is connected to the first sealing component, the first sealing component and the second sealing component are heated to heat and melt the crystal material in the crucible, and the heating furnace can be driven by the second linear module. Move along the axial direction of the first sealing component and the second sealing component, so that in the process of pulling the crystal material upward after growth Following the movement, the rate of change of the temperature around the crystal material is reduced, which is beneficial to the growth of the crystal and improves the yield rate; a vacuum port is set on one side of the second sealing component to evacuate the air inside the first sealing component and the second sealing component, a digital anti-corrosion vacuum gauge is installed on the top of the first sealing component to detect and display the gas pressure in the first sealing component and the second sealing component in real time, an air inlet is set on one side of the second sealing component and an air outlet is set on the top of the first sealing component to circulate protective gas into the first sealing component and the second sealing component, and solenoid valves are set in the air inlet and the air outlet to control the balance of inlet and outlet gas and maintain a constant pressure state. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the first sealing component and the second sealing component of the present invention in the separated state.

[0019] Figure 2 It is a schematic structural diagram of the first sealing component part of the present invention.

[0020] Figure 3 It is a schematic structural diagram of the second sealing component part of the present invention.

[0021] Figure 4 It is a cross-sectional schematic diagram of the docking state of the first sealing component and the second sealing component of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 1-4As shown, the present invention provides a small crystal growth device using a pulling method, comprising: a furnace frame 1, a first sealing component 2 fixedly installed on the furnace frame 1 in a vertical direction, a second sealing component 3 located below the first sealing component 2 and cooperating with the first sealing component 2, and a crucible 4 fixedly installed in the second sealing component 3 for containing crystal materials, the second sealing component 3 is installed on the furnace frame 1 through a first linear module 5, so as to move in a vertical direction under the drive of the first linear module 5, and dock / separate with the first sealing component 2, a heating furnace 6 is sleeved on the outer side of the first sealing component 2, so as to heat the first sealing component 2 and the second sealing component 3 after the second sealing component 3 docks with the first sealing component 2, so as to heat and melt the crystal material in the crucible 4, and the heating furnace 6 is installed on the furnace frame 1 through a second linear module 7, so as to move along the axial direction of the first sealing component 2 and the second sealing component 3 under the drive of the second linear module 7, so as to reduce the rate of change of the temperature around the crystal material during the upward pulling process after the crystal material grows.

[0024] Among them, the first linear module 5 and the second linear module 7 can both adopt the linear module disclosed in Chinese patent CN215806107U, including a motor, a first mounting seat, a coupling, a screw, a screw sleeve, a second mounting seat, a linear guide, a slide, a fixed seat, a first bearing, a support seat, a second bearing and a flexible ring. During operation, the motor drives the screw to rotate through the coupling. When the screw rotates, it drives the screw sleeve mounted thereon to move. Since the screw sleeve is connected to the slide, and the slide is slidably arranged on the linear guide, that is, the screw sleeve will drive the slide to move along the linear guide, and convert the rotation of the motor into linear motion. Specifically in this application, the second sealing component 3 is installed on the slide of the first linear module 5, and the heating furnace 6 is installed on the slide of the second linear module 7. The maximum heating temperature of the heating furnace 6 is 1200 degrees, including two temperature zones, which can be individually controlled to achieve a better temperature gradient. The specific temperature setting can be set according to the experimental requirements.

[0025] The first sealing assembly 2 includes a quartz tube 26 and a first flange 21 connected to the bottom of the quartz tube 26, and the second sealing assembly 3 includes a second flange 31 adapted to the first flange 21, so that after the second sealing assembly 3 is docked with the first sealing assembly 2, the second flange 31 is connected and fixed to the first flange 21 by bolts. The quartz tube 26 and the first flange 21 are sealed by a sealing ring, and the first flange 21 and the second flange 31 are sealed by a sealing gasket and a clamp.

[0026] The second sealing assembly 3 also includes a flange cover 32, through which the second sealing assembly 3 is connected to the slide of the first linear module 5, and the crucible 4 is fixedly mounted on the flange cover 32 through a crucible support tube 41, the height of the crucible support tube 41 being greater than the height of the second sealing assembly 3, so that after the second sealing assembly 3 is docked with the first sealing assembly 2, the crucible 4 is completely extended into the first sealing assembly 2. A thermocouple 42 is installed in the crucible support tube 41 to detect the temperature of the crucible in real time.

[0027] One side of the second sealing component 3 is connected to the air inlet 34 through the second branch pipe 33, so that after the second sealing component 3 is docked with the first sealing component 2, the protective gas is filled into the first sealing component 2 and the second sealing component 3. The top of the first sealing component 2 is connected to the air outlet 23 through the first branch pipe 22. Solenoid valves are provided in the air inlet 34 and the air outlet 23 to control the balance of inlet and outlet gas and maintain a constant pressure state. The top of the first sealing component 2 is connected to the digital anti-corrosion vacuum gauge 24 through the first branch pipe 22, so that when the protective gas is filled into the first sealing component 2 and the second sealing component 3, the gas pressure in the first sealing component 2 and the second sealing component 3 is detected and displayed in real time. The top of the first sealing component 2 is connected to the mechanical pressure relief valve 25 through the first branch pipe 22, so that the gas pressure in the first sealing component 2 and the second sealing component 3 exceeds the preset threshold value. One side of the second sealing component 3 is connected to the vacuum port 35 through the second branch pipe 33, so that the air inside the first sealing component 2 and the second sealing component 3 is evacuated before the protective gas is filled into the first sealing component 2 and the second sealing component 3.

[0028] A touch screen is provided on one side of the furnace frame 1, which can control the moving speed and moving stroke of the heating furnace 6 and the temperature display of the heating furnace 6 and the temperature display of the crucible 4, and can also preset the pulling time, and all data can be saved, recorded and exported.

[0029] When the present invention is working, first, put the crystal material into the crucible 4, start the first linear module 5, drive the second sealing component 3 to move upward to the docking position with the first sealing component 2, send the crucible 4 completely into the first sealing component 2, use bolts to connect and fix the second flange 31 with the first flange 21, and manually put the clamp to achieve sealing. Then, start the vacuum pump connected to the vacuum port 35, and evacuate the inside of the first sealing component 2 and the second sealing component 3. The mechanical pump can be evacuated to 10-2 Torr, and the molecular pump is 10-5 Torr. Next, open the solenoid valve in the air inlet 34 to pass the protective gas, nitrogen or argon, which can be selected according to the experimental requirements, and use the digital display anti-corrosion vacuum gauge 24 to detect and display the gas pressure in the first sealing component 2 and the second sealing component 3 in real time. When the gas pressure in the first sealing component 2 and the second sealing component 3 reaches the preset value, open the solenoid valve in the air outlet 23 to achieve the balance of inlet and outlet gas, maintain a constant pressure state, and the purpose of flushing the protective gas is to minimize the air component in the furnace tube. Then, the heating furnace 6 is started to heat up to a predetermined temperature, and after the temperature is kept constant for a predetermined time, the second linear module 7 is started to move the heating furnace 6 upward to achieve the pulling growth of the crystal material. Finally, after the crystal grows, the first flange 21 and the second flange 31 are manually loosened, the first linear module 5 is started, the second sealing component 3 is driven to move downward and separate from the first sealing component 2, the crucible 4 is pulled out of the first sealing component 2, and the material in the crucible 4 is taken out to complete the experiment.

[0030] The small crystal growth device using the pulling method provided by the present invention adopts a split first sealing component and a second sealing component, and the crucible is arranged on the second sealing component. The second sealing component can be connected to / separated from the first sealing component under the drive of the first linear module. A heating furnace is sleeved on the outer side of the first sealing component. After the second sealing component is connected to the first sealing component, the first sealing component and the second sealing component are heated to melt the crystal material in the crucible. The heating furnace can move along the axial direction of the first sealing component and the second sealing component under the drive of the second linear module, so as to follow the movement during the upward pulling process after the crystal material grows. , reducing the rate of change of temperature around the crystal material, which is beneficial to the growth of the crystal and improves the yield rate; by setting a vacuum port on one side of the second sealing component to evacuate the air inside the first sealing component and the second sealing component, by installing a digital anti-corrosion vacuum gauge on the top of the first sealing component to detect and display the gas pressure in the first sealing component and the second sealing component in real time, by setting an air inlet on one side of the second sealing component and an air outlet on the top of the first sealing component to circulate and fill the first sealing component and the second sealing component with protective gas, and by setting solenoid valves in the air inlet and the air outlet to control the balance of inlet and outlet gas and maintain a constant pressure state.

[0031] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A small crystal growth device using the Czochralski method, characterized in that: include: A furnace frame (1), a first sealing component (2) fixedly mounted on the furnace frame (1) in a vertical direction, a second sealing component (3) located below the first sealing component (2) and cooperating with the first sealing component (2), and a crucible (4) fixedly mounted in the second sealing component (3) for containing crystal materials; The second sealing component (3) is mounted on the furnace frame (1) through the first linear module (5) so as to move in the vertical direction under the drive of the first linear module (5) to dock with / separate from the first sealing component (2); A heating furnace (6) is provided on the outer side of the first sealing component (2) to heat the first sealing component (2) and the second sealing component (3) after the second sealing component (3) is docked with the first sealing component (2), so as to heat and melt the crystal material in the crucible (4); the heating furnace (6) is installed on the furnace frame (1) through the second linear module (7) so as to move along the axial direction of the first sealing component (2) and the second sealing component (3) under the drive of the second linear module (7), so as to reduce the rate of change of the temperature around the crystal material during the process of pulling the crystal material upward after growth.

2. The small crystal growth device according to claim 1, characterized in that: The first sealing component (2) comprises a quartz tube (26) and a first flange (21) connected to the bottom of the quartz tube (26), and the second sealing component (3) comprises a second flange (31) adapted to the first flange (21), so that after the second sealing component (3) is docked with the first sealing component (2), the second flange (31) is connected and fixed to the first flange (21) by bolts.

3. The small crystal growth device according to claim 2, characterized in that: The quartz tube (26) and the first flange (21) are sealed and connected via a sealing ring, and the first flange (21) and the second flange (31) are sealed and connected via a sealing gasket and a clamp.

4. The small crystal growth device according to claim 1, characterized in that: The second sealing component (3) further comprises a flange cover (32), the second sealing component (3) being connected to the first linear module (5) via the flange cover (32), the crucible (4) being fixedly mounted on the flange cover (32) via a crucible support tube (41), the height of the crucible support tube (41) being greater than the height of the second sealing component (3), so that after the second sealing component (3) is butt-jointed with the first sealing component (2), the crucible (4) is completely inserted into the first sealing component (2).

5. The small crystal growth device according to claim 4, characterized in that: A thermocouple (42) is installed in the crucible support tube (41) to detect the temperature of the crucible in real time.

6. The small crystal growth device according to claim 1, characterized in that: One side of the second sealing component (3) is connected to the air inlet (34) via the second branch pipe (33) so that after the second sealing component (3) is docked with the first sealing component (2), protective gas can be filled into the first sealing component (2) and the second sealing component (3). The top of the first sealing component (2) is connected to the air outlet (23) via the first branch pipe (22). Solenoid valves are provided in the air inlet (34) and the air outlet (23) to control the balance of air inlet and outlet and maintain a constant pressure state.

7. The small crystal growth device according to claim 6, characterized in that: The top of the first sealing component (2) is connected to a digital anti-corrosion vacuum gauge (24) via a first branch pipe (22) so as to detect and display the gas pressure inside the first sealing component (2) and the second sealing component (3) in real time when the protective gas is filled into the first sealing component (2) and the second sealing component (3).

8. The small crystal growth device according to claim 7, characterized in that: The top of the first sealing component (2) is connected to a mechanical pressure relief valve (25) via a first branch pipe (22) so as to manually relieve pressure when the gas pressure in the first sealing component (2) and the second sealing component (3) exceeds a preset threshold.

9. The small crystal growth device according to claim 6, characterized in that: One side of the second sealing component (3) is connected to the vacuum port (35) via the second branch pipe (33) so as to evacuate the air inside the first sealing component (2) and the second sealing component (3) before filling the first sealing component (2) and the second sealing component (3) with protective gas.

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