Czochralski method crystal growth diameter control device

Abstract

The utility model relates to the technical field of crystal growth, in particular to a pulling method crystal growth diameter control device which comprises a pulling furnace, a crucible is arranged in the pulling furnace, a heating mechanism used for heating the crucible is further arranged in the pulling furnace, and a driving mechanism is fixedly installed at the top end of the pulling furnace. The output end of the driving mechanism is fixedly connected with a lifting rod, the front end of the lifting rod slidably penetrates through the top end of the lifting furnace to the interior of the lifting furnace and is provided with a chuck, and the front end of the lifting rod is detachably and fixedly provided with a seed crystal through the chuck; an annular mounting groove is formed in the position, close to the front end, of the periphery of the lifting rod, and a stabilizing mechanism is arranged between the periphery of the lifting rod and the inner wall of the lifting furnace through the annular mounting groove; when the lifting rod is lifted, the front end position of the lifting rod is peripherally limited by the stabilizing mechanism, so that the stability of the lifting rod is improved, and the control accuracy of the crystal growth diameter is favorably improved.

Description

Technical Field

[0001] The utility model relates to the technical field of crystal growth, in particular to a device for controlling the diameter of crystal growth using a Czochralski method. Background Art

[0002] The Czochralski process is a commonly used single crystal growth technique, primarily used to produce various types of single crystal materials, particularly semiconductor materials such as silicon (Si), germanium (Ge), and other semiconductor compounds. In the Czochralski process, a doped molten material is placed in a crucible and heated to melt. A relatively cool seed crystal rod (or seed crystal) is then slowly pulled from the melt. During the pulling process, the cooling of the liquid and the solidification of the crystal expand the structure of the various crystals, forming a large-scale single crystal.

[0003] Existing crystal growth devices using the Czochralski method generally include a pulling furnace, which is equipped with a crucible inside and uses an electromagnetic heating device to heat and melt the crystal material. The device is also equipped with a drive device, which is connected to a pulling rod, and a seed crystal is installed at the front end of the pulling rod. During the growth process, the drive device controls the rotation and upward movement of the pulling rod to pull the seed crystal into the crucible. The growth diameter of the crystal is mainly affected by factors such as temperature, pulling speed and rotation speed. In addition, existing crystal growth devices using the Czochralski method are generally also equipped with a control module, which monitors the growth status of the crystal in real time and dynamically adjusts the system's heating temperature, the pulling speed of the pulling rod and the rotation speed to achieve precise control of the crystal diameter. This integrated control system ensures parameter optimization during the crystal growth process, thereby improving the quality and consistency of the final product.

[0004] However, the existing Czochralski crystal growth device still has the following shortcomings during use:

[0005] The lifting rod is generally a slender structure, and the front end of the lifting rod lacks a limiting support, which may cause resonance during the lifting process. This will cause vibration during the lifting process, thereby affecting the stability of the seed crystal and the control accuracy of the crystal diameter. Utility Model Content

[0006] The purpose of the utility model is to provide a device for controlling the diameter of crystal growth by the Czochralski method, so as to solve the problems raised in the above-mentioned background technology.

[0007] The purpose of the utility model can be achieved through the following technical solutions:

[0008] A device for controlling the diameter of crystal growth by a Czochralski method, comprising a pulling furnace, wherein a crucible is provided in the pulling furnace, and a heating mechanism for heating the crucible is also provided in the pulling furnace, a driving mechanism is fixedly installed on the top of the pulling furnace, an output end of the driving mechanism is fixedly connected to a pulling rod, a front end of the pulling rod slides through the top of the pulling furnace to the interior of the pulling furnace, and is provided with a chuck, and a seed crystal is detachably fixedly installed on the front end of the pulling rod through the chuck; further comprising a control module, wherein the control module is electrically connected to the driving mechanism and the heating mechanism; an annular mounting groove is provided on the outer periphery of the pulling rod near the front end, a stabilizing mechanism is provided on the outer periphery of the pulling rod between the annular mounting groove and the inner wall of the pulling furnace, and the stabilizing mechanism is used to improve the stability of the pulling rod during the pulling process;

[0009] The stabilizing mechanism includes a limiting assembly rotatably connected to the periphery of the pulling rod and a plurality of guide assemblies fixedly mounted on the inner wall of the pulling furnace.

[0010] Furthermore, the limiting assembly includes a rotating bearing, the inner ring of the rotating bearing is installed in the annular mounting groove, the outer ring of the rotating bearing is fixedly connected to a plurality of connecting rods equal in number to the multiple groups of guide assemblies, and a sliding sleeve is fixedly installed on one end of the connecting rod away from the rotating bearing.

[0011] Furthermore, the guide assembly includes two bosses fixedly mounted on the inner wall of the pulling furnace, and a guide rod arranged parallel to the pulling rod is fixedly connected between the two bosses;

[0012] The plurality of sliding sleeves are respectively slidably sleeved on the peripheries of the guide rods in the plurality of guide assemblies.

[0013] Furthermore, the driving mechanism includes a slide bar 1 and a slide bar 2 fixedly mounted on the top surface of the pulling furnace, the top ends of the slide bar 1 and the slide bar 2 are fixedly connected to a mounting plate 2, a motor 2 is fixedly mounted on the top surface of the mounting plate 2, the output shaft end of the motor 2 rotates through the mounting plate 2 and is fixedly connected to a screw rod, and the bottom end of the screw rod is rotatably connected to the top surface of the pulling furnace;

[0014] A rotating assembly is commonly installed on the peripheries of the screw rod, the second sliding rod and the first sliding rod.

[0015] Furthermore, the rotating assembly includes a mounting plate 1, a convex plate 1 and a convex plate 2 are fixedly connected to the side of the mounting plate 1, the convex plate 1 is in a through-sliding connection with the slide rod 1, the convex plate 2 is in a through-sliding connection with the slide rod 2, and the convex plate 2 is also in a through-threaded connection with the screw rod;

[0016] The top surface of the mounting plate 1 is fixedly mounted with a motor 1, and the output shaft end of the motor 1 rotates through the mounting plate 1 and is fixedly connected to the top end of the lifting rod.

[0017] Furthermore, the heating mechanism includes a second electromagnetic heater and a first electromagnetic heater fixedly installed on the periphery of the pulling furnace, the coils of the first electromagnetic heater and the second electromagnetic heater are both arranged inside the pulling furnace, and the coil of the first electromagnetic heater is arranged at the upper position of the periphery of the crucible, and the coil of the second electromagnetic heater is arranged at the lower position of the periphery of the crucible.

[0018] Beneficial effects of the utility model:

[0019] When the lifting rod is lifted, the rotating bearing in the stabilizing mechanism rotates relative to the lifting rod. Due to the setting of the annular mounting groove, the rotating bearing moves synchronously with the rise of the lifting rod, and the sliding sleeve also slides synchronously on the guide rod. During the process, multiple connecting rods are always supported between the outer front end position of the lifting rod and the inner wall of the pulling furnace, and the lifting rod is limited circumferentially, thereby improving the stability of the lifting rod, significantly reducing the influence of unstable factors, ensuring the quality and efficiency of crystal growth, and improving the control accuracy of the crystal growth diameter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, it is possible for a person skilled in the art to derive other drawings based on these drawings without inventive effort.

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0022] Figure 2 yes Figure 1 Enlarged view of part A;

[0023] Figure 3 This is a schematic structural diagram of the front end of the outer periphery of the lifting rod in the utility model;

[0024] The accompanying drawings are numerals as follows:

[0025] 1-pulling furnace, 2-first electromagnetic heater, 3-second electromagnetic heater, 4-crucible, 5-convex seat, 6-guide rod, 7-slide sleeve, 8-connecting rod, 9-pulling rod, 10-crystal, 11-seed crystal, 12-slide rod 1, 13-mounting plate 1, 14-convex plate 1, 15-convex plate 2, 16-slide rod 2, 17-screw, 18-motor 1, 19-mounting plate 2, 20-motor 2, 21-rotating bearing, 22-chuck, 23-annular mounting groove. DETAILED DESCRIPTION

[0026] 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 embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0027] Example 1:

[0028] See also Figures 1 to 3 In an embodiment of the utility model, a device for controlling the diameter of crystal growth by a Czochralski method is provided, comprising a pulling furnace 1, wherein a crucible 4 is provided in the pulling furnace 1, and a heating mechanism for heating the crucible 4 is further provided in the pulling furnace 1, a driving mechanism is fixedly installed at the top of the pulling furnace 1, and a pulling rod 9 is fixedly connected to the output end of the driving mechanism, the front end of the pulling rod 9 slides through the top of the pulling furnace 1 to the interior of the pulling furnace 1, and is provided with a chuck 22, and the front end of the pulling rod 9 is detachably fixed with a seed crystal 11 through the chuck 22; further comprising a control module, which is electrically connected to the driving mechanism and the heating mechanism; an annular mounting groove 23 is provided on the outer periphery of the pulling rod 9 near the front end, and a stabilizing mechanism is provided between the outer periphery of the pulling rod 9 and the inner wall of the pulling furnace 1 through the annular mounting groove 23, and the stabilizing mechanism is used to improve the stability of the pulling rod 9 during the pulling process;

[0029] The stabilizing mechanism includes a limiting assembly rotatably connected to the periphery of the pulling rod 9 and a plurality of guide assemblies fixedly mounted on the inner wall of the pulling furnace 1 .

[0030] Among them, the limiting assembly includes a rotating bearing 21, the inner ring of the rotating bearing 21 is installed in the annular mounting groove 23, the outer ring of the rotating bearing 21 is fixedly connected to a plurality of connecting rods 8 equal in number to the multiple groups of guide assemblies, and a sliding sleeve 7 is fixedly installed at one end of the connecting rod 8 away from the rotating bearing 21.

[0031] The guide assembly includes two bosses 5 fixedly mounted on the inner wall of the pulling furnace 1, and a guide rod 6 arranged parallel to the pulling rod 9 is fixedly connected between the two bosses 5;

[0032] The plurality of sliding sleeves 7 are respectively slidably sleeved on the peripheries of the guide rods 6 in the plurality of guide assemblies.

[0033] The driving mechanism includes a slide bar 12 and a slide bar 16 fixedly mounted on the top surface of the pulling furnace 1. The top ends of the slide bars 12 and 16 are fixedly connected to a mounting plate 19. A motor 20 is fixedly mounted on the top surface of the mounting plate 19. The output shaft end of the motor 20 rotates through the mounting plate 19 and is fixedly connected to a screw rod 17. The bottom end of the screw rod 17 is rotationally connected to the top surface of the pulling furnace 1.

[0034] A rotating assembly is installed on the periphery of the screw rod 17, the second slide rod 16 and the first slide rod 12.

[0035] The rotating assembly includes a mounting plate 13, the side of which is fixedly connected to a convex plate 14 and a convex plate 2 15. The convex plate 14 is in a through-sliding connection with the slide bar 12, the convex plate 2 15 is in a through-sliding connection with the slide bar 2 16, and the convex plate 2 15 is also in a through-threaded connection with the screw rod 17.

[0036] A motor 18 is fixedly mounted on the top surface of the mounting plate 13 , and the output shaft end of the motor 18 rotates through the mounting plate 13 and is fixedly connected to the top end of the lifting rod 9 .

[0037] When the utility model is in use:

[0038] The second motor 20 in the driving device drives the screw 17 to lift and lower the lifting rod 9, thereby achieving the lifting action. The first motor 18 can drive the lifting rod 9 to rotate. The heating mechanism heats the crucible 4, so that the material in the crucible 4 melts.

[0039] During the pulling crystallization, the seed crystal 11 is inserted into the molten material in the crucible 4, and then the pulling rod 9 drives the seed crystal 11 upward to form a crystal 10. During the process, the control module monitors the temperature in the crucible 4 and the diameter of the crystal 10 in real time, and controls and adjusts the rotation speed, pulling speed and heating temperature of the pulling rod 9 based on the monitoring data, thereby improving the control accuracy of the growth diameter of the crystal 10.

[0040] Among them, the control module combines modern sensor technology, automatic control and data processing capabilities, has been used in many crystal growth applications, and belongs to the existing technology, which will not be described in detail here.

[0041] When the lifting rod 9 is lifted, the rotating bearing 21 in the stabilizing mechanism rotates relative to the lifting rod 9. Through the setting of the annular mounting groove 23, the rotating bearing 21 moves synchronously with the rise of the lifting rod 9, and the sliding sleeve 7 also slides synchronously on the guide rod 6. During the process, multiple connecting rods 8 are always supported between the outer front end position of the lifting rod 9 and the inner wall of the pulling furnace 1, and the lifting rod 9 is circumferentially limited, thereby improving the stability of the lifting rod 9, significantly reducing the influence of unstable factors, ensuring the quality and efficiency of the growth of the crystal 10, and improving the control accuracy of the growth diameter of the crystal 10.

[0042] Example 2:

[0043] See also Figure 1On the basis of Example 1, the heating mechanism includes a second electromagnetic heater 3 and a first electromagnetic heater 2 fixedly installed on the periphery of the pulling furnace 1. The coils of the first electromagnetic heater 2 and the second electromagnetic heater 3 are both arranged inside the pulling furnace 1, and the coil of the first electromagnetic heater 2 is arranged at the upper position of the periphery of the crucible 4, and the coil of the second electromagnetic heater 3 is arranged at the lower position of the periphery of the crucible 4.

[0044] During the crystallization process, thermal expansion and contraction caused by different temperatures may cause stress concentration within the material, leading to the appearance of cracks. Uniform heating helps to reduce the formation of these stresses. In this embodiment, the crucible 4 is heated by two sets of electromagnetic heaters, the second electromagnetic heater 3 and the first electromagnetic heater 2. By adjusting the power and heating mode of the two sets of heaters, the temperature within the crucible 4 can be precisely controlled, the temperature gradient within the crucible 4 can be reduced, and the temperature difference between the upper and lower parts of the crucible 4 can be significantly reduced, ensuring that the temperature is maintained in the ideal range suitable for crystallization, effectively preventing cracks caused by temperature differences, and thus improving the growth quality and application performance of the crystal.

[0045] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and improvements fall within the scope of the present invention as claimed.

Claims

1. A device for controlling the diameter of crystal growth by a Czochralski method, comprising a pulling furnace (1), wherein a crucible (4) is provided in the pulling furnace (1), and a heating mechanism for heating the crucible (4) is also provided in the pulling furnace (1), a driving mechanism is fixedly installed at the top of the pulling furnace (1), an output end of the driving mechanism is fixedly connected to a pulling rod (9), a front end of the pulling rod (9) slides through the top of the pulling furnace (1) to the interior of the pulling furnace (1), and a chuck (22) is provided, and a seed crystal (11) is detachably fixedly installed at the front end of the pulling rod (9) through the chuck (22); further comprising a control module, wherein the control module is electrically connected to the driving mechanism and the heating mechanism; and characterized in that, An annular mounting groove (23) is provided on the outer periphery of the lifting rod (9) near the front end, and a stabilizing mechanism is provided between the outer periphery of the lifting rod (9) and the inner wall of the pulling furnace (1) through the annular mounting groove (23), and the stabilizing mechanism is used to improve the stability of the lifting rod (9) during the pulling process; The stabilizing mechanism comprises a limiting assembly rotatably connected to the periphery of the pulling rod (9) and a plurality of guide assemblies fixedly mounted on the inner wall of the pulling furnace (1).

2. The device for controlling the diameter of crystal growth by the Czochralski method according to claim 1, wherein: The limiting assembly includes a rotating bearing (21), the inner ring of the rotating bearing (21) is installed in the annular installation groove (23), the outer ring of the rotating bearing (21) is fixedly connected to a plurality of connecting rods (8) equal in number to the plurality of groups of guide assemblies, and a sliding sleeve (7) is fixedly installed on one end of the connecting rod (8) away from the rotating bearing (21).

3. The device for controlling the diameter of crystal growth by the Czochralski method according to claim 2, wherein: The guide assembly comprises two bosses (5) fixedly mounted on the inner wall of the pulling furnace (1), and a guide rod (6) arranged parallel to the pulling rod (9) is fixedly connected between the two bosses (5); The plurality of sliding sleeves (7) are respectively slidably sleeved on the peripheries of the guide rods (6) in the plurality of guide assemblies.

4. The device for controlling crystal growth diameter by a Czochralski method according to claim 1, wherein: The driving mechanism includes a slide bar 1 (12) and a slide bar 2 (16) fixedly mounted on the top surface of the pulling furnace (1), the top ends of the slide bar 1 (12) and the slide bar 2 (16) are fixedly connected to a mounting plate 2 (19), a motor 2 (20) is fixedly mounted on the top surface of the mounting plate 2 (19), an output shaft end of the motor 2 (20) rotates through the mounting plate 2 (19) and is fixedly connected to a screw rod (17), and the bottom end of the screw rod (17) is rotatably connected to the top surface of the pulling furnace (1); A rotating assembly is commonly installed on the periphery of the screw rod (17), the second slide rod (16) and the first slide rod (12).

5. The device for controlling crystal growth diameter by the Czochralski method according to claim 4, characterized in that: The rotating assembly includes a mounting plate 1 (13), the side of the mounting plate 1 (13) is fixedly connected with a convex plate 1 (14) and a convex plate 2 (15), the convex plate 1 (14) is in a through-type sliding connection with the slide rod 1 (12), the convex plate 2 (15) is in a through-type sliding connection with the slide rod 2 (16), and the convex plate 2 (15) is also in a through-type threaded connection with the screw rod (17); A motor 1 (18) is fixedly mounted on the top surface of the mounting plate 1 (13), and the output shaft end of the motor 1 (18) rotates through the mounting plate 1 (13) and is fixedly connected to the top end of the lifting rod (9).

6. The device for controlling crystal growth diameter by a Czochralski method according to claim 1, wherein: The heating mechanism comprises a second electromagnetic heater (3) and a first electromagnetic heater (2) fixedly mounted on the periphery of the pulling furnace (1); the coils of the first electromagnetic heater (2) and the second electromagnetic heater (3) are both arranged inside the pulling furnace (1); the coil of the first electromagnetic heater (2) is arranged at an upper position of the periphery of the crucible (4); and the coil of the second electromagnetic heater (3) is arranged at a lower position of the periphery of the crucible (4).

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