Growth equipment and growth method of monocrystalline silicon

Abstract

The invention provides monocrystalline silicon growth equipment and a growth method, the monocrystalline silicon growth equipment comprises a furnace body, a crucible assembly, an inductance coil, a first thermodetector and a control part, the crucible assembly is arranged in the furnace body to accommodate silicon liquid; the inductance coil is arranged on the periphery of the crucible assembly so as to heat the silicon liquid contained in the crucible assembly; the first thermodetector is arranged above the crucible assembly so as to detect the real-time temperature of the silicon liquid contained in the crucible assembly; the control part controls the power of the inductance coil based on the real-time temperature detected by the first thermodetector. The growth equipment and the growth method of the monocrystalline silicon are high in energy utilization rate and high in temperature control precision.

Description

Technical Field

[0001] The invention relates to a growth device and a growth method for single crystal silicon. Background Art

[0002] At present, most of the thermal field structures of CZ silicon single crystals use graphite resistance heating, and the heating object is the silicon material in the quartz crucible. In this process, since the quartz crucible is wrapped by the graphite crucible, and the thermal conductivity of quartz and graphite materials is low, the thermal energy utilization rate during the heating process is low and the melting time is long, resulting in low production efficiency and serious energy loss. In addition, during the high-temperature process of conventional graphite heaters, heat is transferred from the outside to the inside of the quartz crucible, and the overall temperature of the crucible is relatively high. In addition, a single crucible is prone to abnormal phenomena such as stratification and bulging at high temperatures for a long time, and may even lead to the risk of silicon liquid leakage, which greatly affects production.

[0003] In view of this, it is necessary to improve the existing single crystal silicon growth equipment and growth method to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a single crystal silicon growth device and a growth method with high energy utilization rate and high temperature control accuracy.

[0005] To achieve the above-mentioned object of the invention, the present invention provides a single crystal silicon growth device, comprising:

[0006] Furnace body;

[0007] A crucible assembly is disposed in the furnace body to contain silicon liquid;

[0008] An inductor coil is disposed at the periphery of the crucible assembly to heat the silicon liquid contained in the crucible assembly;

[0009] A first temperature measuring instrument is arranged above the crucible assembly to detect the real-time temperature of the silicon liquid contained in the crucible assembly;

[0010] A control unit controls the power of the inductor coil based on the real-time temperature detected by the first thermometer.

[0011] As a further improvement of the present invention, the crucible assembly is not conductive.

[0012] As a further improvement of the present invention, the single crystal silicon growth equipment also includes an insulation cylinder arranged on the periphery of the crucible assembly, the insulation cylinder includes a first insulation cylinder and a second insulation cylinder which are detachably arranged from each other, and the inductance coil is wound on the outside of the first insulation cylinder.

[0013] As a further improvement of the present invention, the single crystal silicon growth equipment further includes a magnetic yoke disposed in the furnace body, wherein the magnetic yoke is disposed at the periphery of the inductor coil and is disposed close to the inner wall surface of the furnace body.

[0014] As a further improvement of the present invention, the single crystal silicon growth equipment further comprises a heat preservation cotton which is arranged in the furnace body and wrapped around the outside of the inductor coil.

[0015] As a further improvement of the present invention, the single crystal silicon growth equipment further includes a support member connected to the furnace body, and the inductor coil is carried on the support member.

[0016] As a further improvement of the present invention, the first thermometer is arranged on the upper side of the outside of the furnace body and is an infrared thermometer.

[0017] As a further improvement of the present invention, the single crystal silicon growth equipment further includes a second temperature measuring instrument disposed at the lower side of the crucible assembly.

[0018] As a further improvement of the present invention, the second temperature measuring instrument is in contact with the furnace body or the heat-insulating layer inside the furnace body located at the lower side of the crucible assembly.

[0019] To achieve the above-mentioned object of the invention, the present invention also provides a method for growing single crystal silicon, which adopts the above-mentioned single crystal silicon growth device and comprises the following steps:

[0020] Filling the silicon liquid into the crucible assembly;

[0021] energizing the induction coil so that it heats the silicon liquid contained in the crucible assembly;

[0022] The real-time temperature of the silicon liquid contained in the crucible assembly is monitored by a first temperature measuring instrument and fed back to the control unit;

[0023] The control unit controls the power of the inductor coil according to the real-time temperature detected by the first thermometer.

[0024] As a further improvement of the present invention, while performing the step of "monitoring the real-time temperature of the silicon liquid contained in the crucible assembly by means of a first thermometer and feeding it back to the control unit", the temperature of the furnace body located at the lower side of the crucible assembly or the insulation layer inside the furnace body is detected by means of a second thermometer to determine whether it is necessary to power off the magnetic induction coil.

[0025] As a further improvement of the present invention, the step of "the control unit controls the power of the inductor coil according to the real-time temperature detected by the first thermometer" specifically includes: the control unit compares the real-time temperature detected by the first thermometer with the first preset temperature; if the temperature difference ΔT between the two is greater than the first preset temperature difference ΔT0, the control unit adjusts the power of the inductor coil; if the temperature difference between the two is not greater than the first preset temperature difference ΔT0, the control unit controls the power of the inductor coil to remain unchanged.

[0026] Beneficial effects of the present invention: The single crystal silicon growth equipment and growth method of the present invention directly heats the silicon liquid through an inductor coil, has a fast response speed and greatly reduces heat loss, and adjusts the power of the inductor coil according to the temperature data detected by the first thermometer through the control unit to achieve closed-loop control of the silicon liquid temperature, thereby ensuring the stability of the silicon liquid temperature and the quality of the crystal ingot growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the single crystal silicon growth equipment of the present invention.

[0028] Figure 2 yes Figure 1 A flow chart of the single crystal silicon growth equipment is shown.

[0029] Figure 3 It is a schematic flow chart of the method for growing single crystal silicon of the present invention.

[0030] In the figure:

[0031] 100. Single crystal silicon growth equipment;

[0032] 1. Furnace body;

[0033] 2. Crucible assembly; 21. Inner crucible; 23. Outer crucible;

[0034] 31. Inductor coil; 32. Magnetic yoke;

[0035] 41. a first thermometer; 42. a second thermometer;

[0036] 5. Control department;

[0037] 6. Thermal insulation cotton;

[0038] 7. Support parts;

[0039] 8. Insulation tube; 81. First insulation tube; 82. Second insulation tube; 83. Third insulation tube;

[0040] 9. Compression parts. DETAILED DESCRIPTION

[0041] The present invention will be described in detail below in conjunction with the embodiments shown in the accompanying drawings. However, the embodiments do not limit the present invention, and any structural, methodological, or functional changes made by a person skilled in the art based on the embodiments are all within the protection scope of the present invention.

[0042] The terms used herein, such as "upper", "lower", "left", "right", "front", "back", etc., which indicate relative positions in space, are used for the purpose of convenience to describe the relationship between one feature and another feature as shown in the drawings. It is understood that, depending on the placement of the product, the terms of relative positions in space may be intended to include different orientations in addition to the orientation shown in the drawings, and should not be construed as limitations on the claims. In addition, the descriptor "horizontal" used herein is not completely equivalent to being perpendicular to the direction of gravity, and a certain angle of inclination is allowed.

[0043] Please refer to Figures 1 to 3 FIG. 1 is a schematic diagram of a single crystal silicon growth device and a growth method according to the present invention, wherein Figure 1 is a schematic structural diagram of a single crystal silicon growth device 100 of the present invention, Figure 2 is a flow chart of the single crystal silicon growth equipment of the present invention, Figure 3 It is a schematic flow chart of the method for growing single crystal silicon of the present invention.

[0044] Please refer to Figure 1 and Figure 2 As shown, the single crystal silicon growth equipment 100 includes a furnace body 1, a crucible assembly 2 arranged in the furnace body 1 to contain silicon liquid G, an inductor 31, a first thermometer 41 and a control unit 5, wherein the inductor 31 is arranged at the periphery of the crucible assembly 2 to heat the silicon liquid G contained in the crucible assembly 2, the first thermometer 41 is arranged above the crucible assembly 2 to detect the real-time temperature of the silicon liquid G contained in the crucible assembly 2, the control unit 5 controls the power of the inductor 31 based on the real-time temperature detected by the first thermometer 41, and the control unit 5 is communicatively connected with the inductor 31 and the first thermometer 41, so as to realize closed-loop control and regulation of the silicon liquid temperature, thereby ensuring the stability of the growth process and the quality of the single crystal silicon.

[0045] In the present invention, the crucible assembly 2 is not conductive. Specifically, the crucible assembly 2 includes an inner crucible 21 and an outer crucible 23 outside the inner crucible 21 . The outer crucible 23 is made of ceramic material, and the inner crucible 21 is made of quartz material.

[0046] In the present invention, the position of the inductor coil 31 in the height direction is set so that the top of the inductor coil 31 is not higher than the open end of the crucible assembly 2, thereby avoiding energy waste; further, the inductor coil 31 is facing the area at the bottom of the crucible assembly 2 that contains the silicon liquid, thereby only heating the silicon liquid at the bottom of the crucible assembly 2, avoiding heat waste, and reducing damage to the insulation tube 8 described later, thereby extending its service life.

[0047] In the present invention, the inductor coil 31 is a copper tube coil which is hollow and into which a coolant is injected to cool the inductor coil 31 , thereby preventing the inductor coil 31 from overheating or even burning.

[0048] The single crystal silicon growth device 100 further includes a yoke 32 disposed in the furnace body 1. The yoke 32 is disposed on the periphery of the inductor 31 and is disposed close to the inner wall surface of the furnace body 1 to isolate the magnetic field lines from radiating to the furnace body or human body and reduce energy loss.

[0049] In the present invention, the inductor 31 is disposed in the middle of the extension range of the yoke 32 in the height direction, that is, the center of the inductor 31 in the height direction coincides with the center of the yoke 32 in the height direction. In addition, the height of the yoke 32 beyond the inductor 31 in the height direction is set according to the magnetic induction intensity and power of the inductor 31.

[0050] In the present invention, the single crystal silicon growth device 100 further comprises a heat preservation cotton 6 disposed in the furnace body 1 and wrapped around the outer side of the inductor 31. At the same time, the single crystal silicon growth device 100 further comprises a support member 7 connected to the furnace body 1, and the inductor 31 is carried on the support member 7. The support member 7 is made of an insulating material to maintain insulation from the inductor 31, and the furnace body 1 is provided with a mounting hole (not shown) for mounting and fixing the support member 7. Preferably, in this embodiment, the support member 7 is made of a ceramic material.

[0051] The thermal insulation cotton 6 is erected on the support member 7 and is cylindrical. In the radial direction of the furnace body 1, the thermal insulation cotton 6 is located between the inductor 31 and the yoke 32. The inductor 31 is located within the extension range of the thermal insulation cotton 6 in the height direction, thereby utilizing the thermal insulation cotton 6 to achieve preliminary electromagnetic radiation shielding.

[0052] The single crystal silicon growth equipment also includes an insulation tube 8 arranged on the periphery of the crucible assembly 2, and the insulation tube 8 includes a first insulation tube 81 and a second insulation tube 82 which are detachably arranged from each other, and the second insulation tube 82 is arranged on the lower side of the first insulation tube 81, and the inductance coil 31 is coiled on the outside of the first insulation tube 81, and the insulation cotton 6, the support member 7 and the first insulation tube 81 together surround the inductance coil 31.

[0053] Furthermore, in the present embodiment, the insulation tube 8 also has a third insulation tube 83 located on the upper side of the first insulation tube 81, the first insulation tube 81 is sandwiched between the second insulation tube 82 and the third insulation tube 83 in the height direction, and the first insulation tube 81 and the third insulation tube 83 are detachably arranged, the first and second insulation tubes 81 and 82 move upward to achieve separation from the third insulation tube 83, so as to accelerate the cooling of the single crystal silicon growth equipment, reduce damage to the insulation tube 8, and extend the service life, thereby effectively shortening the production time, improving production efficiency, and reducing production costs.

[0054] The thickness of the first thermal insulation tube 81 in the radial direction of the furnace body 1 is smaller than the thickness of the third thermal insulation tube 83 in the radial direction, and the thickness of the third thermal insulation tube 83 in the radial direction is smaller than the thickness of the second thermal insulation tube 82 in the radial direction, that is, the first thermal insulation tube 81 is thinner than the second and third thermal insulation tubes 82, 83 on its upper and lower sides, and the top and bottom ends of the thermal insulation cotton 6 are respectively abutted by the third thermal insulation tube 83 and the second thermal insulation tube 82, so that the thermal insulation cotton 6 can be sandwiched between the second and third thermal insulation tubes 82, 83.

[0055] Preferably, in this embodiment, the thickness of the first insulation tube 81 in the radial direction of the furnace body 1 ranges from 100 to 200 mm, thereby ensuring the heat utilization rate of the inductor 31 and avoiding the risk of excessive temperature of the inductor 31 caused by thermal radiation in the thermal field.

[0056] In addition, the inner walls of the first heat-insulating tube 81, the second heat-insulating tube 82, and the third heat-insulating tube 83 are aligned so that the pressure-resistant member 9 disposed inside thereof can simultaneously protect various parts of the heat-insulating tube 8. At the same time, the gap between the heat-insulating cotton 6 and the magnetic yoke 32 is not less than 2 cm to ensure that there is a certain amount of shaking and offset space when moving up and down.

[0057] In the present invention, the first thermometer 41 is arranged on the upper side of the exterior of the furnace body 1 and is an infrared thermometer. In addition, the single crystal silicon growth device 100 further includes a second thermometer 42 arranged on the lower side of the crucible assembly 2, so that the temperature of the silicon liquid is detected on the upper side of the crucible assembly 2 by the first thermometer 41, and the temperature of the furnace body 1 or the insulation layer in the furnace body 1 is detected on the lower side of the crucible assembly 2 by the second thermometer 42, without manual participation in temperature detection, thereby realizing two-way real-time temperature measurement of the crucible assembly 2, and then real-time monitoring of changes in the ambient temperature of crystal growth, stabilizing the growth process and product quality.

[0058] The second thermometer 42 is in contact with the furnace body 1 located at the lower side of the crucible assembly 2 or the insulation layer inside the furnace body 1, so as to monitor the integrity of the crucible assembly 2 in real time, so as to promptly confirm whether the crucible assembly 2 has any leakage, thereby avoiding the occurrence of accidents. In this embodiment, the second thermometer 42 is a platinum-rhodium alloy thermometer.

[0059] In addition, the present invention also provides a method for growing single crystal silicon, which uses the above-mentioned single crystal silicon growing device 100 and includes the following steps:

[0060] Put silicon liquid G into the crucible assembly 2;

[0061] The inductor 31 is energized to heat the silicon liquid G contained in the crucible assembly 2;

[0062] The real-time temperature of the silicon liquid G contained in the crucible assembly 2 is monitored by the first temperature measuring instrument 41 and fed back to the control unit 5;

[0063] The control unit 5 controls the power of the inductor 31 according to the real-time temperature T detected by the first temperature measuring instrument 41 .

[0064] Specifically, the step of "the control unit 5 controls the power of the inductor 31 according to the real-time temperature T detected by the first thermometer 41" specifically includes: the control unit 5 compares the real-time temperature T detected by the first thermometer 41 with the first preset temperature T1 to obtain a temperature difference ΔT, wherein ΔT=T-T1; if the temperature difference ΔT between the two is greater than the first preset temperature difference ΔT0, the control unit 5 adjusts the power of the inductor 31; if the temperature difference ΔT between the two is not greater than the first preset temperature difference ΔT0, the control unit 5 controls the power of the inductor 31 to remain unchanged, thereby being able to accurately control the temperature of the silicon liquid, reduce the time required for the temperature stabilization link, and improve the thermal stability of the growth equipment.

[0065] The above step "the control unit 5 adjusts the power of the inductor 31" is specifically to calculate the power change value ΔW that needs to be adjusted according to the power adjustment formula of the inductor 31 ΔW=0.3×ΔT. In the present invention, the preset temperature difference ΔT0 is preferably 0.3°C. When the temperature difference ΔT between the real-time temperature T detected by the first thermometer 41 and the first preset temperature T1 is greater than 0.3°C, the power change value ΔW that needs to be adjusted is calculated according to the power adjustment formula. That is to say, in this embodiment, when the temperature difference ΔT is greater than ΔT0, the control unit 5 adjusts the power of the inductor 31 and reduces the power change value ΔW calculated according to the above power calculation formula.

[0066] The step of "the control unit 5 controls the power of the inductor 31 according to the real-time temperature T detected by the first thermometer 41" also includes: the control unit 5 starts comparing the real-time temperature T with the first preset temperature T1 at a predetermined time interval t, and determines whether to adjust the power of the inductor 31 according to the comparison result.

[0067] Furthermore, while performing the step of "monitoring the real-time temperature of the silicon liquid G contained in the crucible assembly 2 by the first thermometer 41 and feeding it back to the control unit 5", the temperature of the furnace body 1 located at the lower side of the crucible assembly 2 or the insulation layer in the furnace body 1 is detected by the second thermometer 42 to determine whether it is necessary to power off the magnetic induction coil 31.

[0068] In addition, the control unit 5 compares the temperature detected by the second thermometer 42 with the second preset temperature T2. When the temperature detected by the second thermometer is greater than the second preset temperature T2, the magnetic induction coil 31 is powered off. In this way, the temperature at the bottom of the furnace body 1 is detected to determine whether the temperature at the bottom of the furnace body is abnormal, and then to determine whether the crucible assembly 2 has abnormal phenomena such as leakage, thereby avoiding the risk of explosion caused by leakage of the crucible assembly 2.

[0069] In the present invention, the single crystal silicon growth equipment and growth method directly heat the silicon liquid through the inductor coil 31, which has a fast response speed and greatly reduces heat loss, and adjusts the power of the inductor coil 31 according to the temperature data detected by the first thermometer 41 through the control unit 5 to achieve closed-loop control of the silicon liquid temperature, thereby ensuring the stability of the silicon liquid temperature and the quality of the crystal ingot growth.

[0070] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0071] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A single crystal silicon growth device, characterized in that: include: Furnace body; A crucible assembly is disposed in the furnace body to contain silicon liquid; An inductor coil is disposed at the periphery of the crucible assembly to heat the silicon liquid contained in the crucible assembly; A first temperature measuring instrument is arranged above the crucible assembly to detect the real-time temperature of the silicon liquid contained in the crucible assembly; A control unit controls the power of the inductor coil based on the real-time temperature detected by the first thermometer.

2. The single crystal silicon growth device according to claim 1, characterized in that: The crucible assembly is non-conductive.

3. The single crystal silicon growth device according to claim 1, characterized in that: The single crystal silicon growth equipment further comprises a heat preservation tube arranged at the periphery of the crucible assembly, the heat preservation tube comprises a first heat preservation tube and a second heat preservation tube which are detachably arranged from each other, and the inductor coil is wound on the outside of the first heat preservation tube.

4. The single crystal silicon growth device according to claim 1, characterized in that: The single crystal silicon growth equipment further comprises a magnetic yoke arranged in the furnace body, wherein the magnetic yoke is arranged at the periphery of the inductor coil and is arranged close to the inner wall surface of the furnace body.

5. The single crystal silicon growth device according to claim 1, characterized in that: The single crystal silicon growth equipment also has heat insulation cotton which is arranged in the furnace body and wrapped around the outside of the inductor coil.

6. The single crystal silicon growth device according to claim 1, characterized in that: The single crystal silicon growth equipment further comprises a support member connected to the furnace body, and the inductor coil is carried on the support member.

7. The single crystal silicon growth device according to claim 1, characterized in that: The first thermometer is arranged on the upper side of the furnace body and is an infrared thermometer.

8. The single crystal silicon growth device according to claim 1, characterized in that: The single crystal silicon growth equipment further includes a second temperature measuring instrument disposed at the lower side of the crucible assembly.

9. The single crystal silicon growth device according to claim 8, characterized in that: The second temperature measuring instrument is in contact with the furnace body or the heat-insulating layer in the furnace body located at the lower side of the crucible assembly.

10. A method for growing single crystal silicon, characterized in that: A single crystal silicon growth device according to any one of claims 1 to 9 is used, and comprises the following steps: Filling the silicon liquid into the crucible assembly; energizing the induction coil so that it heats the silicon liquid contained in the crucible assembly; The real-time temperature of the silicon liquid contained in the crucible assembly is monitored by a first temperature measuring instrument and fed back to the control unit; The control unit controls the power of the inductor coil according to the real-time temperature detected by the first thermometer.

11. The method for growing single crystal silicon according to claim 10, wherein: While performing the step of "monitoring the real-time temperature of the silicon liquid contained in the crucible assembly by means of the first thermometer and feeding it back to the control unit", the temperature of the furnace body or the insulation layer inside the furnace body located at the lower side of the crucible assembly is detected by means of the second thermometer to determine whether it is necessary to power off the magnetic induction coil.

12. The method for growing single crystal silicon according to claim 10, wherein: The step of "the control unit controls the power of the inductor coil according to the real-time temperature detected by the first thermometer" specifically includes: the control unit compares the real-time temperature detected by the first thermometer with the first preset temperature; if the temperature difference ΔT between the two is greater than the first preset temperature difference ΔT0, the control unit adjusts the power of the inductor coil; if the temperature difference between the two is not greater than the first preset temperature difference ΔT0, the control unit controls the power of the inductor coil to remain unchanged.

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