Monocrystalline silicon growth system and growth control method

Abstract

The invention provides a monocrystalline silicon growth system and a growth control method, a monocrystalline silicon growth device in the monocrystalline silicon growth system comprises a crucible, a guide cylinder and a support, the support is mechanically connected with the crucible and the guide cylinder, and the support is used for supporting the guide cylinder to be suspended in the crucible; the crucible is used for bearing molten monocrystalline silicon; the bottom of the guide cylinder comprises a first hole and a second hole; the light output unit transmits light into the crucible through the first hole, the light is reflected at the liquid level of the monocrystalline silicon, the reflected light is transmitted to the light receiving unit through the second hole, and the control unit judges the distance between the liquid level of the monocrystalline silicon in the crucible and the guide cylinder according to the light received by the light receiving unit; the light output unit and the light receiving unit emit and receive light through the first hole and the second hole of the guide cylinder respectively, it can be guaranteed that the distance between the liquid level of monocrystalline silicon in the crucible and the guide cylinder can be accurately obtained, and the accurate obtaining of the distance is beneficial for improving defect control of monocrystalline silicon.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of single crystal silicon preparation, and in particular to a single crystal silicon growth system and a growth control method. Background Art

[0002] High-purity single-crystal silicon is an important semiconductor material that can be made into diodes, triodes, thyristors and various integrated circuits (including the chips and CPUs in people's computers). It can also be made into solar photovoltaic cells to convert radiation energy into electrical energy.

[0003] The growth conditions of high-purity single crystal silicon are multifaceted, including temperature, pressure, atmosphere, purity of silicon raw materials and growth methods. These factors interact with each other and jointly determine the growth rate and quality of single crystal silicon. In order to meet the needs of high-performance semiconductor devices, we need high-quality single crystal silicon rods with low defects. An important parameter affecting the defect properties of single crystal silicon is the liquid mouth distance, that is, the distance from the guide tube to the liquid surface of the silicon melt. This parameter may change with changes in other conditions during the growth of single crystal silicon, thereby affecting the growth and quality of single crystal silicon. Therefore, real-time measurement of the liquid mouth distance is of great significance to the defect control of single crystal silicon. Summary of the invention

[0004] An embodiment of the present invention provides a single crystal silicon growth system and a growth control method, wherein a light output unit and a light receiving unit respectively emit and receive light through a first hole and a second hole of a guide tube, thereby ensuring accurate acquisition of the distance between the liquid level of the single crystal silicon in the crucible and the guide tube, thereby ensuring defect control of the single crystal silicon.

[0005] In a first aspect, an embodiment of the present invention provides a single crystal silicon growth system, comprising: a single crystal silicon growth device, a light output unit, a light receiving unit and a control unit;

[0006] The single crystal silicon growth device comprises a crucible, a guide tube and a bracket, wherein the bracket is mechanically connected to the crucible and the guide tube respectively, and the bracket is used to support the guide tube to be suspended in the crucible; the crucible is used to carry molten single crystal silicon; the bottom of the guide tube comprises a first hole and a second hole;

[0007] The light output unit transmits the light into the crucible through the first hole, and the light is reflected at the liquid surface of the single crystal silicon, and the reflected light is transmitted to the light receiving unit through the second hole;

[0008] The control unit is connected to the light receiving unit, and the control unit determines the distance between the liquid level of the single crystal silicon in the crucible and the guide tube according to the light received by the light receiving unit.

[0009] Optionally, the first hole comprises a first side edge, and the first side edge extends along a first direction;

[0010] The second hole comprises a second side edge, and the second side edge extends along a second direction;

[0011] The first direction and the second direction intersect at a side of the bottom of the guide tube close to the crucible.

[0012] Optionally, the opening area of ​​the first hole is S1, and the opening area of ​​the second hole is S2;

[0013] Among them, S1<S2.

[0014] Optionally, the aperture of the first hole is L1, and the spot diameter of the light output by the light output unit is L;

[0015] Among them, L1>L.

[0016] Optionally, the light output unit includes a laser.

[0017] Optionally, the light receiving unit includes a plurality of photosensitive elements, and the plurality of photosensitive elements are arranged in an array.

[0018] Optionally, the photosensitive element includes a light sensor.

[0019] Optionally, the control unit is connected to the bracket, and is used to adjust the position of the crucible through the bracket.

[0020] In a second aspect, an embodiment of the present invention provides a growth control method for single crystal silicon, which is applied to the single crystal silicon growth system described in any one of the first aspects, wherein the single crystal silicon growth system comprises: a single crystal silicon growth device, a light output unit, a light receiving unit and a control unit; the single crystal silicon growth device comprises a crucible, a guide tube and a bracket, the bracket is mechanically connected to the crucible and the guide tube respectively, and the bracket is used to support the guide tube to be suspended in the crucible; the crucible is used to carry molten single crystal silicon; the bottom of the guide tube comprises a first hole and a second hole;

[0021] The control method comprises:

[0022] Controlling the light emitted by the light output unit to be transmitted into the crucible through the first hole, and the light is transmitted to the liquid surface of the single crystal silicon to be reflected;

[0023] Controlling the light receiving unit to obtain the reflected light through the second hole;

[0024] The distance between the liquid level of the single crystal silicon in the crucible and the guide tube is determined according to the light received by the light receiving unit.

[0025] Optionally, after judging the distance between the liquid level of the silicon monocrystalline in the crucible and the guide tube according to the light received by the light receiving unit, the method further includes:

[0026] According to the distance, the position of the crucible is adjusted.

[0027] An embodiment of the present invention provides a single crystal silicon growth system, in which a single crystal silicon growth device includes a crucible, a guide tube and a bracket, the bracket is mechanically connected to the crucible, and the bracket is mechanically connected to the guide tube, that is, the bracket is used to fix and adjust the setting position of the crucible and the guide tube. Specifically, the bracket is used to support the guide tube to be suspended in the crucible, and the bottom of the guide tube is adjusted to be located in the crucible, and the crucible is used to carry molten single crystal silicon; further, the bottom of the guide tube includes a first hole and a second hole, the first hole is used to transmit the light emitted by the light output unit to the single crystal silicon in the crucible, because the single crystal silicon is in a molten state, the light is transmitted to the liquid surface of the single crystal silicon and will be reflected, and the reflected light is then transmitted to the light receiving unit through the second hole; the light receiving unit is connected to the control unit, and the control unit can judge the distance between the liquid surface of the single crystal silicon and the bottom of the guide tube according to the light information received by the light receiving unit, which is equivalent to accurately obtaining the liquid mouth distance, and the accurate acquisition of this distance is beneficial to improving the defect control of the single crystal silicon.

[0028] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required to describe the embodiments. Obviously, the drawings introduced are only drawings of a part of the embodiments to be described in the present invention, rather than all the drawings. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 is a schematic structural diagram of a single crystal silicon growth system provided by an embodiment of the present invention;

[0031] Figure 2 is an enlarged schematic diagram of the bottom of a guide tube provided by an embodiment of the present invention;

[0032] Figure 3 is a bottom top view schematic diagram of a guide tube provided by an embodiment of the present invention;

[0033] Figure 4is a structural schematic diagram of a light receiving unit provided by an embodiment of the present invention;

[0034] Figure 5 is a flow chart of a method for controlling growth of single crystal silicon provided by an embodiment of the present invention;

[0035] Figure 6 It is a flow chart of another method for controlling the growth of single crystal silicon provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] 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.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a system, product or device comprising a series of units is not necessarily limited to those steps or units clearly listed, but may include other units that are not clearly listed or inherent to these products or devices.

[0038] Figure 1 is a schematic diagram of a single crystal silicon growth system provided by an embodiment of the present invention, with reference to Figure 1 As shown, an embodiment of the present invention provides a single crystal silicon growth system 10, which includes: a single crystal silicon growth device 100, a light output unit 200, a light receiving unit 300 and a control unit 400; the single crystal silicon growth device 100 includes a crucible 110, a guide tube 120 and a bracket (not specifically shown in the figure), the bracket is mechanically connected to the crucible 110 and the guide tube 120 respectively, and the bracket is used to support the guide tube 120 to be suspended in the crucible 110; the crucible 110 is used to carry molten single crystal silicon 20; The bottom 121 of the guide tube 120 includes a first hole 121a and a second hole 121b; the light output unit 200 transmits the light to the crucible 110 through the first hole 121a, and the light is reflected at the liquid surface of the single crystal silicon 20, and the reflected light is transmitted to the light receiving unit 300 through the second hole 121b; the control unit 400 is connected to the light receiving unit 300, and the control unit 400 determines the distance between the liquid surface of the single crystal silicon 20 in the crucible 110 and the guide tube 120 according to the light received by the light receiving unit 300.

[0039] Among them, the single crystal silicon growth system 10 includes a single crystal silicon growth device 100, which is used to carry silicon raw materials and prepare single crystal silicon by adjusting factors such as temperature and pressure. Specifically, the single crystal silicon growth device 100 includes a crucible 110 and a guide tube 120. The crucible 110 can be used to carry molten single crystal silicon 20, and its stable liquid surface can form a reflecting surface. The guide tube 120 can be understood as a heat shield. The presence of the guide tube 120 can guide inert gas such as argon to flow in a directional manner, ensuring that the molten single crystal silicon 20 in the crucible 110 is always filled with argon, so that the single crystal silicon 20 grows under the protection of the surrounding atmosphere.

[0040] Furthermore, the single crystal silicon growth device 100 further includes a bracket (not specifically shown in the figure), which is mechanically connected to the crucible 110 and the guide tube 120, that is, the bracket can support the crucible 110 and the guide tube 120, and the bracket can also adjust the positions of the crucible 110 and the guide tube 120. Specifically, the bracket is used to support the guide tube 120 to be suspended in the crucible 110. It should be noted that Figure 1 The bracket is not specifically shown in the figure. For different single crystal silicon growth systems 10, the setting shape and position of the bracket can be adaptively adjusted. The setting of the bracket is used to ensure that the positions of the crucible 110 and the guide tube 120 are fixed and adjusted. The embodiment of the present invention does not provide a specific description of this.

[0041] Among them, reference Figure 1 As shown, the bottom 121 of the guide tube 120 includes a first hole 121a and a second hole 121b. The first hole 121a and the second hole 121b penetrate the bottom 121, and light can be transmitted through the first hole 121a and the second hole 121b.

[0042] Furthermore, the single crystal silicon growth system 10 further includes a light output unit 200 and a light receiving unit 300. The light output unit 200 can emit light, and the light receiving unit 300 is used to obtain light. In combination with the first hole 121a and the second hole 121b on the guide tube 120, light is emitted and obtained. Specifically, the light output unit 200 is transmitted to the crucible 110 through the first hole 121a, and the light is reflected at the liquid surface of the single crystal silicon 20, and the reflected light is transmitted to the light receiving unit 300 through the second hole 121b. For example, refer to Figure 1 As shown, the light output unit 200 transmits the emitted light to the liquid surface of the single crystal silicon 20 in the crucible 110 through the first hole 121a, and the light is reflected at the liquid surface, and the reflected light is transmitted to the light receiving unit 300 through the second hole 121b. Figure 1As shown, when the liquid level of the single crystal silicon 20 in the crucible 110 is at the first position C1, the light a1 output by the light output unit 200 is transmitted to the liquid level of the single crystal silicon 20 through the first hole 121a, that is, the light a1 is transmitted to the first position C1 for reflection, and the reflected light b1 is transmitted to the light receiving unit 300 through the second hole 121b; when the liquid level of the single crystal silicon 20 in the crucible 110 is at the second position C2, the light a2 output by the light output unit 200 is transmitted to the liquid level of the single crystal silicon 20 through the first hole 121a, that is, the light a2 is transmitted to the second position C2 for reflection, and the reflected light b2 is transmitted to the light receiving unit 300 through the second hole 121b. When the single crystal silicon 20 in the crucible 110 is at different liquid level heights, the reflected different light b1 and light b2 will be transmitted to the light receiving unit 300, that is, the light receiving unit 300 receives different light. Furthermore, the light receiving unit 300 is connected to the control unit 400, and the control unit 400 can judge the liquid level of the single crystal silicon 20 according to the different light rays received by the light receiving unit 300, and judge the distance L between the liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120, that is, the control unit 400 can accurately judge the liquid outlet distance. Figure 1 As shown, when the liquid level of the single crystal silicon 20 is at the first position C1, the control unit 400 determines that the distance between the current liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120 is L1 based on the light b1 received by the light receiving unit 300; when the liquid level of the single crystal silicon 20 is at the second position C2, the control unit 400 determines that the distance between the current liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120 is L2 based on the light b2 received by the light receiving unit 300.

[0043] Optionally, the control unit 400 and the light receiving unit 300 may be electrically connected or communicated, and the specific connection method is not specifically shown in the embodiment of the present invention. The control unit 400 may also be electrically connected to the light output unit 200 to control whether the light output unit 200 outputs light according to demand.

[0044] In summary, an embodiment of the present invention provides a single crystal silicon growth system, wherein a single crystal silicon growth device of the single crystal silicon growth system comprises a crucible, a guide tube and a bracket, wherein the bracket is mechanically connected to the crucible, and the bracket is mechanically connected to the guide tube, that is, the bracket is used to fix and adjust the setting position of the crucible and the guide tube, specifically, the bracket is used to support the guide tube to be suspended in the crucible, and adjust the bottom of the guide tube to be located in the crucible, and the crucible is used to carry molten single crystal silicon; further, the bottom of the guide tube comprises a first hole and a second hole, the first hole is used to transmit the light emitted by the light output unit to the single crystal silicon in the crucible, since the single crystal silicon is in a molten state, the light will be reflected when it is transmitted to the liquid surface of the single crystal silicon, and the reflected light will be transmitted to the light receiving unit through the second hole; the light receiving unit is connected to the control unit, and the control unit can judge the distance between the liquid surface of the single crystal silicon and the bottom of the guide tube according to the light information received by the light receiving unit, which is equivalent to accurately obtaining the liquid mouth distance, and the accurate acquisition of this distance is beneficial to improving the defect control of the single crystal silicon.

[0045] Figure 2 is an enlarged schematic diagram of the bottom of a guide tube provided by an embodiment of the present invention, with reference to Figure 1 and Figure 2 As shown, the first hole 121a includes a first side 121a1, which extends along a first direction X1; the second hole 121b includes a second side 121b1, which extends along a second direction X2; wherein the first direction X1 and the second direction X2 intersect at a side of the bottom 121 of the guide tube 120 close to the crucible 110.

[0046] Specifically, refer to Figure 2 As shown, the first hole 121a includes a first side 121a1, and the first side 121a1 extends along the first direction X1, that is, the first hole 121a can be understood as an inclined aperture set on the bottom 121. Similarly, the second hole 121b includes a second side 121b1, and the second side 121b1 extends along the second direction X2, that is, the second hole 121b can also be understood as an inclined aperture set on the bottom 121.

[0047] For further reference, Figure 2 As shown, the first direction X1 and the second direction X2 intersect at the bottom 121 of the guide tube 120 close to the crucible 110. Figure 2 The reference direction intersection point D can be used. That is, the inclination directions of the sides of the first hole 121a and the second hole 121b are opposite and converge at a side close to the crucible 110. In combination with the transmission path of the light, by adjusting the inclination direction of the sides of the first hole 121a and the second hole 121b, it can be ensured that the light receiving unit 300 acquires the reflected light, thereby ensuring accurate judgment of the liquid mouth distance, which is beneficial to improving the defect control of single crystal silicon.

[0048] Figure 3 is a bottom top view of a guide tube provided by an embodiment of the present invention, and further reference is made to Figures 1 to 3 As shown, the opening area of ​​the first hole 121a is S1, and the opening area of ​​the second hole 121b is S2; wherein S1<S2.

[0049] Specifically, refer to Figure 3 As shown, Figure 3 The bottom 121 of the guide tube 120 is a top view of the bottom 121. The first hole 121a and the second hole 121b both penetrate the bottom 121. Figure 3 The 123 marked in the figure can be understood as the area where the surface of the first hole 121a in the bottom 121 is located away from the crucible 110. Figure 3 The 124 marked in the figure can be understood as the area where the surface of the first hole 121a in the bottom 121 is located near the crucible 110. Figure 3 The 125 marked in the figure can be understood as the area where the second hole 121b in the bottom 121 is located on the side away from the crucible 110. Figure 3 The mark 126 may be understood as the area where the surface of the second hole 121 b in the bottom 121 close to the crucible 110 is located.

[0050] Furthermore, the opening area of ​​the first hole 121a is smaller than the opening area of ​​the second hole 121b. The first hole 121a only needs to ensure that the light can be transmitted to the crucible 110, so the size of the first hole 121a does not need to be designed to be too large. However, in order to ensure that the light receiving unit 300 can obtain the light more comprehensively, the size of the second hole 121b needs to be adjusted to be larger, which can ensure that the light is better transmitted to the light receiving unit 300, thereby improving the accuracy of judging the liquid mouth distance.

[0051] Optionally, the distance between the first hole 121a and the second hole 121b can be adaptively adjusted to ensure that the light transmitted through the first hole 121a to the liquid surface for reflection can be guided out through the second hole 121b. If the distance between the first hole 121a and the second hole 121b is adjusted, the position of the light receiving unit 300 needs to be adaptively adjusted to ensure that the light receiving unit 300 can better receive the light transmitted from the second hole 121b. In the actual production process, different processes are set for the liquid port distance, and the distance between the first hole 121a and the second hole 121b can be adjusted in a targeted manner.

[0052] Continue to refer Figures 1 to 3 As shown, the aperture of the first hole 121a is L1, and the spot diameter of the light output by the light output unit 200 is L; wherein, L1>L.

[0053] Among them, the first hole 121a is mainly used to pass the light emitted by the light output unit 200 and transmit it to the liquid surface of the single crystal silicon 20 in the crucible 110, so the aperture of the first hole 121a must be larger than the spot diameter of the light output by the light output unit 200 to ensure that the light can be transmitted through the first hole 121a.

[0054] Furthermore, the first hole 121a has a relatively small diameter and can also be used for positioning, that is, to ensure the relative position relationship between the fixed crucible 110 and the guide tube 120, etc., and further ensure the stability and reliability of the overall structure of the single crystal silicon growth system 10.

[0055] The light output unit 200 includes a laser.

[0056] Specifically, the light output unit 200 may be a laser, which is used to emit laser light, and transmit the laser light through the first hole 121a to the liquid surface of the single crystal silicon 20 in the crucible 110 for reflection. Exemplarily, the laser may be a gas laser, a fixed laser, or a semiconductor laser, etc., and the type of the laser is not specifically limited, and the laser frequency output by the laser is not specifically limited.

[0057] Figure 4 is a schematic diagram of a light receiving unit provided by an embodiment of the present invention, with reference to Figure 1 , Figure 2 and Figure 4 As shown, the light receiving unit 300 includes a plurality of photosensitive elements 301 , and the plurality of photosensitive elements 301 are arranged in an array.

[0058] Specifically, the light receiving unit 300 includes a plurality of photosensitive elements 301 arranged in an array. When the photosensitive element 301 receives the light reflected by the second hole 121b, the photosensitive element 301 can be activated, and when the photosensitive element 301 does not receive the light, it is not activated. The control unit 400 is used to obtain the number and position of the activated photosensitive elements 301 to judge the reflected light, and judge the distance between the liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120 according to the light.

[0059] Exemplary, reference Figure 4 As shown, Figure 4 The photosensitive elements 301 are arranged in an array along the row direction and the column direction, wherein the region N is used to reflect the region where light irradiates the photosensitive element 301 and the photosensitive element 301 is activated. Figure 2 The first position c1 and the second position c2 correspond to areas where different activated photosensitive elements 301 are located in the light receiving unit 300 .

[0060] Continue to refer Figure 1 , Figure 2 and Figure 4 As shown, the photosensitive element 301 includes a light sensor.

[0061] For further reference, Figure 1 , Figure 2 and Figure 4 As shown, the photosensitive element 301 includes a light sensor, and when the photosensitive element 301 is activated, an electrical signal can be generated accordingly. Since the light receiving unit 300 is electrically connected to the control unit 400, the electrical signal generated by the activated photosensitive element 301 can be transmitted to the control unit 400, and combined with the position of the activated photosensitive element 301, the liquid level position of the single crystal silicon 20 can be further judged.

[0062] Optionally, the control unit 400 is connected to the bracket, and is used to adjust the position of the crucible 110 through the bracket.

[0063] The control unit 400 determines the distance between the silicon monocrystalline 20 and the bottom 121 of the guide tube 120, i.e., the liquid inlet distance, according to the signal transmitted by the light receiving unit 300. If the determined liquid inlet distance does not meet the expected setting range, the liquid inlet distance can be further adjusted by adjusting the position of the crucible 110, and the distance between the silicon monocrystalline 20 and the bottom 121 in the crucible 110 is further determined after the position is further adjusted in combination with the light output unit 200 and the light receiving unit 300, so as to ensure that the liquid inlet distance meets the required range, and the data of the liquid inlet distance can be obtained and determined in a timely manner.

[0064] Optionally, the control unit 400 may be provided with an alarm module, and a safe range of liquid inlet distance may be pre-stored, for example, 30 mm to 60 mm. If the liquid inlet distance detected by the control unit 400 exceeds the safe range, an alarm may be given, such as a sound prompt or a light prompt, etc., which is not specifically limited in the embodiment of the present invention. The control unit 400 may also adjust the position of the crucible 110 to ensure that the distance between the liquid surface of the single crystal silicon 20 in the crucible 110 and the bottom 121 of the guide tube 120 is within the safe range, and further obtain and detect the specific value of the liquid inlet distance.

[0065] Based on the same inventive concept, an embodiment of the present invention provides a method for controlling the growth of single crystal silicon. Figure 5 1 is a flow chart of a growth control method for single crystal silicon provided by an embodiment of the present invention, the growth control method comprising:

[0066] S110, controlling the light emitted by the light output unit to be transmitted into the crucible through the first hole, and the light is transmitted to the liquid surface of the single crystal silicon to be reflected.

[0067] Among them, the single crystal silicon growth system includes a single crystal silicon growth device, which is used to carry silicon raw materials and prepare single crystal silicon by adjusting factors such as temperature and pressure. Specifically, the single crystal silicon growth device includes a crucible and a flow tube. The crucible can be used to carry molten single crystal silicon, and its stable liquid surface can form a reflecting surface. The flow tube can be understood as a heat shield. The presence of the flow tube can guide inert gas such as argon to flow in a directional manner, ensuring that the molten single crystal silicon in the crucible is always filled with argon, so that the single crystal silicon grows under the protection of the surrounding atmosphere. Furthermore, the single crystal silicon growth device also includes a bracket, which is mechanically connected to the crucible and the flow tube respectively, that is, the bracket can support the crucible and the flow tube, and the bracket can also adjust the position of the crucible and the flow tube. Specifically, the bracket is used to support the flow tube to be suspended in the crucible.

[0068] The bottom of the guide tube includes a first hole and a second hole, the first hole and the second hole penetrate the bottom, and light can be transmitted through the first hole and the second hole. Further, the single crystal silicon growth system also includes a light output unit, the light output unit can emit light, and the emitted light is transmitted to the single crystal silicon in the crucible through the first hole, that is, the light of the light output unit is transmitted to the liquid surface of the single crystal silicon through the first hole.

[0069] S120, controlling the light receiving unit to obtain reflected light through the second hole.

[0070] S130, judging the distance between the liquid level of the single crystal silicon in the crucible and the guide tube according to the light received by the light receiving unit.

[0071] Furthermore, the single crystal silicon growth system also includes a light receiving unit, which is used to acquire light. In combination with the first hole and the second hole on the guide tube, light is emitted and acquired. Specifically, the light output unit transmits the light into the crucible through the first hole, and the light is reflected at the liquid surface of the single crystal silicon, and the reflected light is transmitted to the light receiving unit through the second hole. Exemplarily, the light output unit transmits the emitted light to the liquid surface of the single crystal silicon in the crucible through the first hole, and the light is reflected at the liquid surface, and the reflected light is transmitted to the light receiving unit through the second hole. Specifically, refer to Figure 1As shown, when the liquid level of the single crystal silicon 20 in the crucible 110 is at the first position C1, the light a1 output by the light output unit 200 is transmitted to the liquid level of the single crystal silicon 20 through the first hole 121a, that is, the light a1 is transmitted to the first position C1 for reflection, and the reflected light b1 is transmitted to the light receiving unit 300 through the second hole 121b; when the liquid level of the single crystal silicon 20 in the crucible 110 is at the second position C2, the light a2 output by the light output unit 200 is transmitted to the liquid level of the single crystal silicon 20 through the first hole 121a, that is, the light a2 is transmitted to the second position C2 for reflection, and the reflected light b2 is transmitted to the light receiving unit 300 through the second hole 121b.

[0072] Specifically, when the single crystal silicon in the crucible is at different liquid level heights, different reflected light and light will be transmitted to the light receiving unit, that is, the light receiving unit receives different light. Furthermore, the light receiving unit is connected to the control unit, and the control unit can judge the liquid level of the single crystal silicon based on the different light received by the light receiving unit, and judge the distance between the liquid level of the single crystal silicon and the bottom of the guide tube, that is, the control unit can accurately judge the liquid mouth distance. Figure 1 As shown, when the liquid level of the single crystal silicon 20 is at the first position C1, the control unit 400 determines that the distance between the current liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120 is L1 based on the light b1 received by the light receiving unit 300; when the liquid level of the single crystal silicon 20 is at the second position C2, the control unit 400 determines that the distance between the current liquid level of the single crystal silicon 20 and the bottom 121 of the guide tube 120 is L2 based on the light b2 received by the light receiving unit 300.

[0073] Optionally, the control unit and the light receiving unit may be electrically connected or communicated, and the specific connection method is not specifically shown in the embodiment of the present invention. The control unit may also be electrically connected to the light output unit to control whether the light output unit outputs light according to demand.

[0074] In summary, an embodiment of the present invention provides a growth control method for single crystal silicon, and the growth control method includes: controlling the light emitted by the light output unit to be transmitted to the crucible through the first hole; controlling the light receiving unit to obtain the reflected light through the second hole; and judging the distance between the liquid surface of the single crystal silicon in the crucible and the guide tube according to the light received by the light receiving unit. The control unit can judge the distance between the liquid surface of the single crystal silicon and the bottom of the guide tube according to the light information received by the light receiving unit, which is equivalent to accurately obtaining the liquid mouth distance. The accurate acquisition of this distance is beneficial to improving the defect control of single crystal silicon.

[0075] Furthermore, Figure 6 is a flow chart of another method for controlling the growth of single crystal silicon provided by an embodiment of the present invention, with reference to Figure 6 As shown, the growth control method also includes:

[0076] S210, controlling the light emitted by the light output unit to be transmitted into the crucible through the first hole, and the light is transmitted to the liquid surface of the single crystal silicon to be reflected.

[0077] Optionally, the light output unit may be a laser, which is used to emit laser light and transmit the laser light through the first hole to the liquid surface of the single crystal silicon in the crucible for reflection. Exemplarily, the laser may be a gas laser, a fixed laser or a semiconductor laser, etc., and the type of the laser is not specifically limited, and the laser frequency output by the laser is not specifically limited.

[0078] S220, controlling the light receiving unit to obtain reflected light through the second hole.

[0079] Optionally, the light receiving unit may include a plurality of photosensitive elements arranged in an array, and the photosensitive elements may be activated when receiving light reflected by the second hole, and are inactivated when not receiving light. The control unit is used to obtain the number and position of the activated photosensitive elements to judge the reflected light, and judge the distance between the liquid level of the single crystal silicon and the bottom of the guide tube according to the light.

[0080] Furthermore, the photosensitive element includes a light sensor, and when the photosensitive element is activated, an electrical signal can be generated accordingly. Since the light receiving unit is electrically connected to the control unit, the electrical signal generated by the activated photosensitive element can be transmitted to the control unit, and combined with the position of the activated photosensitive element, the liquid level position of the single crystal silicon can be further judged.

[0081] S230, judging the distance between the liquid level of the single crystal silicon in the crucible and the guide tube according to the light received by the light receiving unit.

[0082] S240. Adjust the position of the crucible according to the distance.

[0083] The control unit determines the distance between the silicon monocrystal and the bottom of the guide tube, i.e., the liquid mouth distance, according to the signal transmitted by the light receiving unit. If the determined liquid mouth distance does not meet the expected setting range, the liquid mouth distance can be further adjusted by adjusting the position of the crucible, and the distance between the silicon monocrystal and the bottom of the crucible is further determined after the position is further adjusted in combination with the light output unit and the light receiving unit, so as to ensure that the liquid mouth distance meets the required range, and the data of the liquid mouth distance can be obtained and determined in a timely manner.

[0084] Optionally, the control unit may be provided with an alarm module, and a safe range of liquid-mouth distance may be pre-stored, for example, 30 mm to 60 mm. If the liquid-mouth distance detected by the control unit exceeds the safe range, an alarm prompt may be issued, such as a sound prompt or a light prompt, etc., which is not specifically limited in the embodiment of the present invention. The control unit may also adjust the position of the crucible to ensure that the distance between the liquid level of the single crystal silicon in the crucible and the bottom of the guide tube is within the safe range, and further obtain and detect the specific value of the liquid-mouth distance.

[0085] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A single crystal silicon growth system, characterized in that: include: A single crystal silicon growing device, a light output unit, a light receiving unit and a control unit; The single crystal silicon growth device comprises a crucible, a guide tube and a bracket, wherein the bracket is mechanically connected to the crucible and the guide tube respectively, and the bracket is used to support the guide tube to be suspended in the crucible; the crucible is used to carry molten single crystal silicon; the bottom of the guide tube comprises a first hole and a second hole; The light output unit transmits the light into the crucible through the first hole, and the light is reflected at the liquid surface of the single crystal silicon, and the reflected light is transmitted to the light receiving unit through the second hole; The control unit is connected to the light receiving unit, and the control unit determines the distance between the liquid level of the single crystal silicon in the crucible and the guide tube according to the light received by the light receiving unit.

2. The single crystal silicon growth system according to claim 1, characterized in that: The first hole comprises a first side edge, and the first side edge extends along a first direction; The second hole comprises a second side edge, and the second side edge extends along a second direction; The first direction and the second direction intersect at a side of the bottom of the guide tube close to the crucible.

3. The single crystal silicon growth system according to claim 1, characterized in that: The opening area of ​​the first hole is S1, and the opening area of ​​the second hole is S2; Among them, S1<S2.

4. The single crystal silicon growth system according to claim 3, characterized in that: The aperture of the first hole is L1, and the spot diameter of the light output by the light output unit is L; Among them, L1>L.

5. The single crystal silicon growth system according to claim 1, characterized in that: The light output unit includes a laser.

6. The single crystal silicon growth system according to claim 1, characterized in that: The light receiving unit includes a plurality of photosensitive elements, and the plurality of photosensitive elements are arranged in an array.

7. The single crystal silicon growth system according to claim 6, characterized in that: The photosensitive element includes a light sensor.

8. The single crystal silicon growth system according to claim 1, characterized in that: The control unit is connected to the bracket and is used for adjusting the position of the crucible through the bracket.

9. A method for controlling the growth of single crystal silicon, applied to the single crystal silicon growth system according to any one of claims 1 to 8, the single crystal silicon growth system comprising: A single crystal silicon growth device, a light output unit, a light receiving unit and a control unit; the single crystal silicon growth device comprises a crucible, a guide tube and a bracket, the bracket is mechanically connected to the crucible and the guide tube respectively, and the bracket is used to support the guide tube to be suspended in the crucible; the crucible is used to carry molten single crystal silicon; the bottom of the guide tube comprises a first hole and a second hole; Characterized in that the control method comprises: Controlling the light emitted by the light output unit to be transmitted into the crucible through the first hole, and the light is transmitted to the liquid surface of the single crystal silicon to be reflected; Controlling the light receiving unit to obtain the reflected light through the second hole; The distance between the liquid level of the single crystal silicon in the crucible and the guide tube is determined according to the light received by the light receiving unit.

10. The growth control method according to claim 9, characterized in that: After judging the distance between the liquid level of the silicon monocrystalline in the crucible and the guide tube according to the light received by the light receiving unit, the method further includes: According to the distance, the position of the crucible is adjusted.

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