Seed crystal head and crystal growth equipment

Abstract

The invention belongs to the technical field of semiconductors, and discloses a seed crystal head and crystal growth equipment. The seed crystal head comprises a seed crystal rope, a lifting head assembly, a sensor assembly, a control assembly and an adjusting assembly, and one end of the lifting head assembly clamps the seed crystal rope and can drive the seed crystal rope to rotate and move in the first direction; the sensor assembly is used for detecting the swinging direction and the swinging distance of the detection part of the seed crystal rope; the control assembly is in signal connection with the sensor assembly, and information of the swing direction and the swing distance can be transmitted to the control assembly; the adjusting assembly is arranged between the sensor assembly and the lifting head assembly and comprises a driving part and a reset part, the control assembly is in signal connection with the driving part, and when the swing distance is larger than a preset value, the control assembly controls the driving part to rotate to the swing direction position in the second direction; the reset piece drives the seed crystal rope to adjust the swinging distance in the direction opposite to the swinging direction. According to the present invention, the interruption problem of the single crystal growth can be avoided so as to improve the continuity and the efficiency of the production process.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a seed crystal head and crystal growth equipment. Background Art

[0002] The full name of CZ crystal growth method is Czochralski method, also known as crystal pulling method or Czochralski method. It is a major method for growing semiconductor crystals and is widely used in the solar energy and semiconductor industries.

[0003] The basic principle of the CZ crystal growth method is to heat and melt high-purity polycrystalline silicon materials, and then immerse the single crystal silicon seed crystal in the melt at a suitable temperature and perform welding. By controlling parameters such as the pulling speed and temperature of the seed crystal, the melt gradually crystallizes on the seed crystal and grows into a single crystal silicon rod.

[0004] However, current CZ crystal growth equipment cannot overcome the problem of the soft rope of the seed crystal head swinging over a large range due to environmental vibration (such as ground vibration), resulting in interruption of single crystal growth, thereby reducing production efficiency and continuity. Summary of the invention

[0005] The object of the present invention is to provide a seed crystal head and crystal growth equipment, which are used to solve the problem of interruption of single crystal growth caused by a large range of swinging of the seed crystal rope of the seed crystal head due to environmental vibration, thereby improving the continuity and efficiency of the production process.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Seed head, including:

[0008] Seed rope;

[0009] A pulling head assembly, one end of which clamps the seed crystal rope and can drive the seed crystal rope to rotate and move along a first direction;

[0010] A sensor assembly, used to detect the swing direction and swing distance of the detection part of the seed crystal rope;

[0011] A control component, wherein the control component is connected to the sensor component by signal, and information of the swing direction and the swing distance can be transmitted to the control component;

[0012] An adjustment component is arranged between the sensor component and the lifting head component, and the adjustment component includes a driving member and a reset member connected to the driving member signal. The control component is connected to the driving member signal. When the swing distance is greater than a preset value, the control component controls the driving member to rotate along the second direction to the position in the swing direction, so that the reset member drives the seed crystal rope to adjust the swing distance in the opposite direction of the swing direction.

[0013] As an optional solution for the seed crystal head, the sensor assembly includes a plurality of groups of opposite-radiation photoelectric sensors arranged at intervals along the circumferential direction of the detection position of the seed crystal rope.

[0014] As an optional solution for a seed crystal head, the sensor assembly includes two groups of the opposing photoelectric sensors, and the connection lines of the two groups of the opposing photoelectric sensors are perpendicular.

[0015] As an optional solution for a seed crystal head, the detection accuracy of the through-beam photoelectric sensor does not exceed 0.005 mm.

[0016] As an optional solution for the seed crystal head, the adjustment component includes a joint, the seed crystal rope is passed through the joint, the joint is transmission-connected to the driving member, and the reset member is fixed on the joint.

[0017] As an optional solution of the seed crystal head, the reset member includes an air blowing head, and the air blowing head is used to blow air toward the seed crystal rope to reversely compensate for the swing distance of the seed crystal rope.

[0018] As an optional solution for a seed crystal head, the control component is connected to the air blowing head by signal, and the control component can adjust the pressure and gas flow of the gas of the air blowing head according to the swing distance.

[0019] As an optional solution for a seed crystal head, the gas is an inert gas.

[0020] As an optional solution for the seed crystal head, the reset member further includes an air blowing pipe connected to the air blowing head, and a stop valve is provided on the air blowing pipe.

[0021] A crystal growth device comprises a seed crystal head as described in any of the above schemes.

[0022] Beneficial effects:

[0023] In the first aspect of the present invention, the sensor component detects the swing direction and the swing distance of the detection part of the seed crystal rope, and the control component can collect the information of the swing direction and the swing distance transmitted by the sensor component. The sensor component is arranged at the front end of the seed crystal rope, and the adjustment component is arranged between the sensor component and the pulling head component. Once the detected swing distance is greater than the preset value, the control component will perform active correction, and the control component drives the driving member to move, and the driving member can rotate along the second direction. At this time, the reset member can drive the seed crystal rope to adjust the swing distance in the opposite direction of the swing direction, so as to achieve accurate correction of the position of the seed crystal rope after the swing exceeds a certain range, thereby offsetting the swing amount of the seed crystal rope caused by factors such as vibration, avoiding interruption of the single crystal growth process, and thus improving the continuity and efficiency of the production process.

[0024] In the second aspect of the present invention, the crystal growth equipment based on the seed crystal head can avoid the interruption of the single crystal growth process caused by the vibration of the seed crystal rope due to vibration factors, thereby effectively improving the continuity and efficiency of the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of a seed crystal head provided by an embodiment of the present invention;

[0026] Figure 2 yes Figure 1 A local enlarged view at point A;

[0027] Figure 3 is a schematic diagram of the layout of the sensor assembly on the seed crystal head provided by an embodiment of the present invention;

[0028] Figure 4 It is a schematic structural diagram of a side view of a sensor assembly on a seed crystal head provided by an embodiment of the present invention.

[0029] In the figure:

[0030] X, first direction; Y, second direction;

[0031] 1. Seed crystal rope;

[0032] 2. Pulling head assembly;

[0033] 3. Sensor assembly; 31. Opposing photoelectric sensor;

[0034] 4. Adjustment assembly; 41. Reset member; 411. Air blowing head; 412. Air blowing pipe; 413. Stop valve; 42. Connector. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0036] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0039] Please see attached Figure 1 and attached Figure 2The first aspect of the present embodiment relates to a seed crystal head for growing a single crystal silicon rod using a CZ crystal growth method. Specifically, the seed crystal head includes a seed crystal rope 1, a lifting head assembly 2, a sensor assembly 3, a control assembly and an adjustment assembly 4. Among them, one end of the lifting head assembly 2 clamps the seed crystal rope 1 and can drive the seed crystal rope 1 to rotate and move along the first direction X; the sensor assembly 3 is used to detect the swing direction and swing distance of the detection part of the seed crystal rope 1; the control assembly is connected to the sensor assembly 3 by signal, and the information of the swing direction and the swing distance can be transmitted to the control assembly; the adjustment assembly 4 is arranged between the sensor assembly 3 and the lifting head assembly 2, and the adjustment assembly 4 includes a driving member and a reset member 41 connected to the driving member signal, and the control assembly is connected to the driving member signal. When the swing distance is greater than a preset value, the control assembly controls the driving member to rotate along the second direction Y to the position of the swing direction, so that the reset member 41 drives the seed crystal rope 1 to adjust the swing distance in the opposite direction of the swing direction.

[0040] In the present embodiment, the material of the seed crystal rope 1 is mainly tungsten or molybdenum, which can be specifically divided into tungsten wire rope, tungsten steel wire rope and alloy wire rope containing molybdenum, etc. The selection of the material of the seed crystal rope 1 mainly depends on the requirements of the working temperature, tensile strength and corrosion resistance of the single crystal furnace. The pulling head assembly 2 can adopt a conventional existing structure, one end of which clamps one end of the seed crystal rope 1, and during the crystal growth production process, the pulling head assembly 2 must be able to continuously pull the crystal rod at a uniform speed, and at the same time, it must also keep the crystal rod continuously and stably rotating. Therefore, the pulling head assembly 2 can drive the seed crystal rope 1 to rotate and move along the first direction X, and the first direction X is the axial direction of the seed crystal rope 1; during the crystal growth process, due to the vibration of the equipment or the vibration of the external environment (such as earthquakes, etc.), the seed crystal rope 1 will swing within a certain range. The reference basis for the swing is the swing direction and the swing distance that deviates from the axis. There are two situations in the actual swinging process. When the swing distance is relatively small, that is, the swing distance does not exceed the preset value, this small swing has little effect on the growth of monocrystalline silicon, generally will not interrupt production, and does not affect the efficiency and continuity of production. Therefore, there is no need to perform reverse compensation correction on the swing distance; however, once the swing distance exceeds the preset value, the swing amplitude is large, which will have a greater impact on the growth of monocrystalline silicon. At this time, production needs to be interrupted and targeted adjustments need to be made. This large swing will seriously affect the efficiency and continuity of production.

[0041] Further, the present embodiment uses the sensor assembly 3 to detect the swing direction and swing distance of the detection part of the seed rope 1, and the control assembly can collect the information of the swing direction and swing distance transmitted by the sensor assembly 3, and selectively transmit the control signal to the adjustment assembly 4 according to whether the swing distance exceeds the preset value. The sensor assembly 3 is arranged at the front end of the seed rope 1, and the adjustment assembly 4 is arranged between the sensor assembly 3 and the lifting head assembly 2. Once the swing distance detected is greater than the preset value, the control assembly will perform active correction. Specifically, the control assembly drives the driving member to move, and the driving member can rotate along the second direction Y. The second direction Y is the rotation direction, specifically the rotation direction with the theoretical axis of the seed rope 1 as the axis. At this time, the reset member 41 can drive the seed rope 1 to adjust the swing distance in the opposite direction of the swing direction, so as to achieve accurate correction of the position of the seed rope 1 after the swing exceeds a certain range, thereby offsetting the swing amount of the seed rope 1 caused by factors such as vibration, avoiding the interruption of the single crystal growth process, and thus improving the continuity and efficiency of the production process.

[0042] Please see attached Figure 3 and attached Figure 4 Optionally, the sensor assembly 3 includes a plurality of groups of opposing photoelectric sensors 31 arranged at intervals along the circumferential direction of the detection position of the seed rope 1 .

[0043] Those skilled in the art can reasonably select the number of groups of the through-beam photoelectric sensors 31 and the angle of the outer periphery of the corresponding ring detection part according to the coverage detection range of the through-beam photoelectric sensors 31.

[0044] Preferably, the sensor assembly 3 includes two groups of opposing photoelectric sensors 31 , and the connecting line of the two groups of opposing photoelectric sensors 31 is perpendicular.

[0045] In this embodiment, two groups of through-beam photoelectric sensors 31 are used, and the connecting line of the two groups of through-beam photoelectric sensors 31 is perpendicular, that is, one through-beam photoelectric sensor 31 is set every 90 degrees, and correspondingly, the other through-beam photoelectric sensor 31 used in pair with it is located on the opposite side. Through this arrangement, the effectiveness of the detection range coverage can be guaranteed as much as possible and the number of groups of through-beam photoelectric sensors 31 used can be reduced as much as possible, thereby ensuring economy.

[0046] Preferably, the detection accuracy of the through-beam photoelectric sensor 31 does not exceed 0.005 mm.

[0047] In this embodiment, since the diameter of the seed crystal rope 1 is relatively small, especially the diameter range of the tungsten seed crystal soft rope is usually between 1.8mm and 6.0mm, and the swing distance of the seed crystal rope 1 is set to be smaller, the detection accuracy of the opposing photoelectric sensor 31 is below 0.005mm, which can ensure the accuracy and versatility of the detection of seed crystal ropes 1 of various diameter specifications.

[0048] Optionally, the adjustment component 4 includes a joint 42 , the seed crystal rope 1 is passed through the joint 42 , the joint 42 is transmission-connected to the driving member, and the reset member 41 is fixed on the joint 42 .

[0049] Specifically, the joint 42 is cylindrical, and the seed crystal rope 1 is passed through the center of the joint 42. The driving member can be a rotating motor, which can drive the joint 42 to rotate to a preset position according to the signal of the control component, so that the reset member 41 is exactly at the angle where the seed crystal rope 1 needs to correct its position.

[0050] Further, the reset member 41 comprises a blowing head 411, and the blowing head 411 is used to blow gas toward the seed rope 1 to reversely compensate for the swing distance of the seed rope 1. Preferably, the gas is an inert gas.

[0051] In this embodiment, the blowing head 411 can blow air to the seed rope 1 after being adjusted to the angle of the correct position, wherein the gas is an inert gas, which can not only apply the required extrusion force to the seed rope 1, but also avoid affecting the growth quality of the single crystal silicon rod due to chemical reactions.

[0052] Optionally, the control component is connected to the air blowing head 411 by signal, and the control component can adjust the gas pressure and gas flow of the air blowing head 411 according to the swing distance.

[0053] In this embodiment, the standard gas pressure value and standard gas flow value required for correcting the swing distance of the seed rope 1 can be obtained through the preliminary fitting test, and the control component is used to control the blowing head 411 to achieve control of the gas pressure and gas flow, thereby ensuring the correction effect of the seed rope 1.

[0054] Optionally, the resetting member 41 further includes an air blowing pipe 412 connected to the air blowing head 411 , and a stop valve 413 is provided on the air blowing pipe 412 .

[0055] The stop valve 413 can instantly cut off the gas from entering the air blowing head 411, which ensures that after the seed rope 1 is reset, the air supply from the air blowing head 411 can be instantly stopped to avoid the seed rope 1 swinging in the opposite direction due to the continuous blowing force of the air blowing head 411, thereby ensuring the correction effect of the seed rope 1. In addition to the stop valve 413, a pressure regulating valve is also provided to adjust the air supply pressure of the air blowing head 411.

[0056] A second aspect of this embodiment also relates to a crystal growth device, which includes the above seed crystal head.

[0057] The crystal growth equipment based on the seed crystal head can avoid the interruption of the single crystal growth process caused by the vibration of the seed crystal rope 1 due to vibration factors, thereby effectively improving the continuity and efficiency of the production process.

[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A seed crystal head, characterized in that: include: Seed rope (1); A pulling head assembly (2), one end of which clamps the seed crystal rope (1) and can drive the seed crystal rope (1) to rotate and move along a first direction (X); A sensor assembly (3) for detecting a swing direction and a swing distance of a detection portion of the seed crystal rope (1); A control component, the control component being connected to the sensor component (3) by signal, and information about the swing direction and the swing distance can be transmitted to the control component; An adjustment component (4) is arranged between the sensor component (3) and the lifting head component (2), and the adjustment component (4) includes a driving member and a reset member (41) connected to the driving member signal. The control component is connected to the driving member signal. When the swing distance is greater than a preset value, the control component controls the driving member to rotate along the second direction (Y) to the position in the swing direction, so that the reset member (41) drives the seed crystal rope (1) to adjust the swing distance in the opposite direction of the swing direction.

2. The seed crystal head according to claim 1, characterized in that: The sensor assembly (3) comprises a plurality of groups of opposite-radiation photoelectric sensors (31) arranged at intervals along the circumference of the detection position of the seed crystal rope (1).

3. The seed crystal head according to claim 2, characterized in that: The sensor assembly (3) comprises two groups of the opposing photoelectric sensors (31), and the connecting lines of the two groups of the opposing photoelectric sensors (31) are perpendicular.

4. The seed crystal head according to claim 3, characterized in that: The detection accuracy of the opposing photoelectric sensor (31) does not exceed 0.005 mm.

5. The seed crystal head according to claim 1, characterized in that: The adjustment assembly (4) comprises a joint (42), the seed crystal rope (1) is passed through the joint (42), the joint (42) is transmission-connected to the driving member, and the reset member (41) is fixed on the joint (42).

6. The seed crystal head according to claim 5, characterized in that: The reset member (41) comprises an air blowing head (411), and the air blowing head (411) is used to blow air toward the seed crystal rope (1) to reversely compensate for the swing distance of the seed crystal rope (1).

7. The seed crystal head according to claim 6, characterized in that: The control component is connected to the air blowing head (411) by signal, and the control component can adjust the pressure and gas flow of the gas of the air blowing head (411) according to the swing distance.

8. The seed crystal head according to claim 7, characterized in that: The gas is an inert gas.

9. The seed crystal head according to claim 6, characterized in that: The resetting member (41) further comprises an air blowing pipe (412) connected to the air blowing head (411), and a stop valve (413) is provided on the air blowing pipe (412).

10. Crystal growth equipment, characterized in that: Comprising the seed crystal head as described in any one of claims 1-9.

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