Movable quartz pin device and liquid level distance measuring system

Abstract

The utility model provides a movable quartz pin device and a liquid level distance measuring system. The device comprises a quartz pin and a retraction control assembly, the quartz pin penetrates through the bottom of the guide cylinder through a through hole in the bottom of the guide cylinder, and when the quartz pin device is in a measurement state, the lower end of the quartz pin extends out of the bottom of the guide cylinder; in the feeding process of silicon raw materials, the quartz pin is put away, the situation that the quartz pin is broken and falls off due to collision in the feeding process, silicon melt is polluted, or the positioning function is affected due to the fact that the quartz pin is stained with splashed molten silicon is avoided, and the better liquid level positioning effect is achieved. The retracting and releasing control assembly comprises a quartz pin connecting piece, a connecting piece moving mechanism and a moving mechanism control unit, and the quartz pin connecting piece is fixedly connected with the upper end of the quartz pin. The system is used for measuring the distance between a guide cylinder and silicon melt in the monocrystalline silicon growth process, a quartz pin and an inverted image of the quartz pin are shot through a camera by adopting an inverted image method and are uploaded to an image processor, and the image processor calculates to obtain an accurate liquid level distance.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology and relates to a single crystal silicon growth technology, and in particular to a movable quartz pin device and a liquid level distance measurement system. Background Art

[0002] Single crystal silicon is widely used in infrared spectrum frequency optical components, infrared and radiation detectors, integrated circuits, solar cells, etc. It is currently the most important, largest-yield, fastest-growing, and most widely used semiconductor material. There are currently two main technologies for preparing single crystal silicon: the Float-Zone Method (Fz method) and the Czochralski Method (Cz method). Among them, single crystal silicon prepared by the Cz method is mainly used in microelectronic integrated circuits and solar cells.

[0003] The Cz method for preparing single crystal silicon is to melt silicon in a quartz crucible, insert a seed crystal into the surface of the molten silicon for welding and pull to grow single crystal silicon. A guide tube is set above the crucible and filled with argon as a protective gas. Since the distance between the guide tube and the melt affects the flow of argon, the evaporation of impurities, the temperature gradient of the melt and other parameters, which in turn affects the quality and yield of the crystal, the measurement and control of the liquid surface distance is very important. The current liquid surface distance measurement uses a quartz pin installed at the bottom of the guide tube, and a camera is used to capture the reflection of the quartz pin to locate the liquid surface. However, the installed quartz pin is easy to fall off, and it is easy to break due to collision during the addition of silicon raw materials. The fallen quartz debris will contaminate the silicon material, and the splashed molten silicon sticking to the quartz pin will also affect the liquid surface positioning, thereby affecting the quality of the single crystal silicon crystal.

[0004] Therefore, how to prevent the quartz pin from falling or breaking is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] The purpose of the present application is to provide a movable quartz pin device and a liquid level distance measurement system, which are used to solve the problem that the quartz pin falls or breaks, causing molten silicon contamination or the quartz pin cannot be used.

[0006] In a first aspect, the present application provides a movable quartz pin device, comprising a quartz pin and a retractable control assembly; the quartz pin passes through the bottom of the guide tube through a through hole at the bottom of the guide tube, and when the quartz pin device is in a measuring state, the lower end of the quartz pin protrudes from the bottom of the guide tube to form a reflection on the surface of the silicon melt for liquid level positioning;

[0007] The retractable control assembly includes a quartz pin connector, a connector moving mechanism, and a moving mechanism control unit, wherein the quartz pin connector is fixedly connected to the upper end of the quartz pin. The retractable control assembly is used to control the quartz pin to be retracted or lowered. Specifically, the moving mechanism control unit controls the connector moving mechanism, and the connector moving mechanism further controls the movement of the quartz pin through the quartz pin connector, so that the quartz pin is lowered when in a measuring state and retracted when no measurement is required.

[0008] In the present application, the quartz pin is controlled to be lowered or retracted through a retraction and extension control assembly fixedly connected to the quartz pin, so that the quartz pin can be retracted when measurement is not needed, especially when it is retracted inside the guide tube during the feeding process of silicon raw material, to avoid the quartz pin from being broken by bumps and scratches, which is beneficial for the quartz pin to be able to normally position the liquid level and extend the service life. At the same time, since the fallen quartz pin fragments will cause contamination of the silicon melt, the present application can also avoid the quartz pin fragments from contaminating the silicon melt, which is beneficial to the preparation of high-purity single crystal silicon and further improves the quality of the prepared single crystal silicon.

[0009] In one embodiment of the present invention, the quartz pin connector is a rack connector, the upper end of the rack connector is a rack, and the lower end is a smooth strip structure to ensure that the single crystal furnace is a sealed structure, and the connector moving mechanism includes a gear and a motor for controlling the rotation of the gear, and the gear and the rack are meshed with each other. The motor is used to control the rotation of the gear, and when the gear rotates, the rack connector is controlled to move up and down, and further control the movement of the quartz pin.

[0010] In one embodiment of the present invention, the moving mechanism control unit is a switch or a motor driving chip, which is used to control the connecting member moving mechanism.

[0011] In one embodiment of the present invention, a heat insulation layer is provided under the motor, and an opening is provided on the heat insulation layer, and the rack connecting member passes through the opening to be fixedly connected to the quartz pin. The heat insulation layer is used to prevent the motor from being damaged by high temperature and ensure the normal operation of the movable quartz pin device.

[0012] In one embodiment of the present invention, the rack connecting member is made of a high temperature resistant material to prevent the rack connecting member from being affected by high temperature and ensure the normal operation of the movable quartz pin device.

[0013] In one embodiment of the present invention, a slot is provided at the lower end of the quartz pin connector, and the upper end of the quartz pin is embedded in the slot and fixedly connected to the lower end of the quartz pin connector, so that the quartz pin is fixedly and reliably connected to the lower end of the quartz pin connector to prevent the quartz pin from falling.

[0014] In one embodiment of the present invention, a horizontal piece is provided at the junction of the quartz pin connector and the outer portion of the quartz pin, the horizontal piece is fixedly connected to the quartz pin, and the diameter of the horizontal piece is larger than the diameter of the quartz pin, so that the quartz pin is fixed at the bottom of the guide tube.

[0015] In one embodiment of the present invention, a groove is provided at the bottom of the guide tube, the through hole is located in the groove, and when the quartz pin device is in a measuring state, the horizontal member fits into the groove.

[0016] In one embodiment of the present invention, the horizontal member is made of graphite material.

[0017] In a second aspect, the present application provides a liquid level distance measurement system, comprising:

[0018] A guide tube, equipped with a movable quartz pin device as described above;

[0019] A camera, which is arranged outside the guide tube and is used to photograph the quartz pins and the reflection of the quartz pins in the movable quartz pin device;

[0020] An image processor is connected to the camera and is used to obtain the image taken by the camera and calculate the distance from the silicon melt surface to the guide tube according to the image.

[0021] In the present application, a quartz pin and its reflection are photographed by a camera, and an image processor acquires the photographed image. Based on the pixel distance between the quartz pin and its reflection, the distance between the guide tube and the silicon melt surface is calculated, thereby achieving precise positioning of the silicon melt surface, which is conducive to the preparation of higher quality single crystal silicon crystals.

[0022] As described above, the present application provides a movable quartz pin device and a liquid level distance measurement system, wherein the liquid level distance measurement system accurately locates the silicon melt liquid level through the quartz pin, which is conducive to the preparation of higher quality single crystal silicon crystals. At the same time, the movable quartz pin device controls the movement of the quartz pin through the retractable control component, so that the quartz pin can be used for measurement normally and can be retracted when measurement is not required, especially in the process of adding silicon raw materials, to reduce the possibility of the quartz pin being knocked and broken, and avoid the influence of the quartz pin breaking and falling on the silicon melt liquid level positioning and the pollution of the silicon melt, which is conducive to the preparation of higher quality single crystal silicon crystals. And the quartz pin is fixedly connected to the quartz pin connector through the slot at the lower end of the quartz pin connector, and a horizontal piece is provided at the connection between the two to further avoid the quartz pin from falling off, and the diameter of the horizontal piece is larger than the diameter of the quartz pin, which can avoid the quartz pin from shaking and instability, and further improve the accuracy of the silicon melt liquid level positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1Shown is a schematic diagram of the cross-sectional structure of the single crystal furnace equipment described in an embodiment of the present application.

[0024] Figure 2 Shown is a schematic diagram of the quartz pin device described in an embodiment of the present application in the state of lowering the quartz pin.

[0025] Figure 3 Shown is a schematic diagram of the quartz pin device described in an embodiment of the present application in a state where the quartz pins are retracted.

[0026] Figure 4 Shown is a schematic diagram of the connection structure of the quartz pin and the quartz pin connector described in an embodiment of the present application.

[0027] Component number description

[0028] 100 Liquid level distance measurement system

[0029] 111 Camera

[0030] 112 Observation window

[0031] 113 Image Processor

[0032] 120 guide tube

[0033] 121 Through hole

[0034] 122 groove

[0035] 131 Quartz Pin

[0036] 140 Retraction and Extension Control Components

[0037] 141 Rack Connector

[0038] 142 Gear

[0039] 143 Motor

[0040] 144 Motor Control Unit

[0041] 145 Card slot

[0042] 151 Insulation

[0043] 161 Horizontal pieces

[0044] 211 Silicon Ingot

[0045] 212 Silicon Molten Liquid

[0046] 213 Crucible

[0047] 214 Heater

[0048] 215 Furnace cover

[0049] 216 Furnace Room

[0050] 217 Seed crystal rod DETAILED DESCRIPTION

[0051] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0052] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0053] The following embodiments of the present application provide a movable quartz pin device and a liquid level distance measuring system. The liquid level distance measuring system is used to locate the liquid level of molten silicon during the growth of single crystal silicon. The movable quartz pin device is used to retract the quartz pin when the liquid level distance measurement does not need to be measured. The process of growing single crystal silicon in a traditional single crystal furnace includes: the seed crystal rod descends to contact the silicon melt liquid level, and forms a solid-liquid interface with the silicon melt. Under a suitable thermal field environment, the seed crystal is rotated and slowly pulled upward, and a single crystal silicon crystal rod is formed through processes such as necking, shoulder release, shoulder rotation, equal diameter growth and tailing. In this process, the distance from the silicon melt liquid level to the guide tube needs to be measured. When the silicon melt liquid level drops, silicon raw material needs to be added. For example Figure 1The figure shows a cross-sectional structure diagram of a single crystal furnace device applicable to the movable quartz pin device and the liquid level distance measurement system of the present application. The single crystal furnace includes a furnace cover 215, a furnace chamber 216, a guide tube 120, a crucible 213, and a heater 214. The crucible 213 is arranged in the furnace chamber 216, the heater 214 is arranged on the periphery of the crucible 213, and the guide tube 120 is arranged above the crucible 213. When single crystal silicon grows, the crucible 213 is filled with silicon melt 212, and the silicon crystal rod 211 gradually grows out of the silicon melt 212 through the rotating upward seed crystal rod 217. In order to measure the distance between the liquid surface of the silicon melt 212 and the guide tube 120, a liquid surface distance measurement system 100 is installed on the guide tube 120. Specifically, the lower end of the quartz pin 131 protrudes from the bottom of the guide tube 120, forming a reflection on the liquid surface of the silicon melt 212. The camera 111 photographs the quartz pin 131 and its reflection through the observation window 112 on the single crystal furnace, and uploads the image to the image processor 113. The image processor 113 can calculate the distance between the guide tube 120 and the liquid surface of the silicon melt 212.

[0054] It should be noted that the current method of placing the quartz pin 131 at the bottom of the guide tube 120 is not stable. The quartz pin 131 is easy to fall or shake, resulting in inaccurate measurement of the distance between the guide tube 120 and the liquid surface of the silicon melt 212. In addition, in the process of adding silicon raw materials to the crucible 213, the quartz pin 131 is easy to be knocked, causing the quartz pin 131 to break and fall, causing contamination of the silicon melt 212. The quartz pin 131 is contaminated with the splashed silicon melt 212, which will also affect the accuracy of subsequent liquid surface distance measurements.

[0055] The movable quartz pin device and liquid level distance measurement system provided by the present application can accurately measure the distance between the guide tube 120 and the liquid level of the silicon melt 212, and the movable quartz pin device can retract the quartz pins when measurement is not required, so that the quartz pins are not easy to fall off and break, and have a good use effect. The following will be described in detail with reference to the accompanying drawings, and the principle and implementation method of a movable quartz pin device and liquid level distance measurement system of this embodiment will be explained in detail, so that those skilled in the art can understand the movable quartz pin device and liquid level distance measurement system of this embodiment without creative labor.

[0056] like Figure 2 As shown, this embodiment provides a movable quartz pin device, including: a quartz pin 131 and a retractable control assembly 140. The quartz pin 131 is used to form a reflection on the surface of the silicon melt 212 for measurement, and a through hole 121 is set at the bottom of the guide tube 120. The through hole 121 can just accommodate the quartz pin 131 to pass through. The length of the quartz pin 131 is greater than the length of the through hole 121, so that the quartz pin 131 can be put down through the through hole 121 on the guide tube 120 and stick out of the guide tube 120 to form a reflection.

[0057] The retractable control assembly 140 is fixedly connected to the quartz pin 131 and is used to control the movement of the quartz pin 131. Specifically, when the single crystal furnace needs to be charged, the retractable control assembly 140 retracts the quartz pin 131 and places it in the guide tube 120 to avoid being hit by the silicon raw material and causing it to break; when the single crystal furnace is charged, it is necessary to make the seed crystal rod 217 contact with the liquid surface, or to perform processes such as necking, shouldering, shoulder turning, equal diameter growth and tailing, and it is necessary to measure the distance between the guide tube 120 and the liquid surface of the silicon melt 212. The retractable control assembly 140 lowers the quartz pin 131 so that its lower end protrudes from the bottom of the guide tube 120, and the quartz pin 131 and its reflection can be captured by the camera 111 for distance measurement. Since the quartz pin 131 can be retracted to avoid collision during charging, the service life of the quartz pin 131 is increased, and the silicon melt 212 can be prevented from being contaminated, which is conducive to the growth of silicon crystal rods 211 with better crystal quality.

[0058] Specifically, the retraction and extension control component 140 includes: a quartz pin connector, a connector moving mechanism, and a moving mechanism control unit. Among them, the quartz pin connector is fixedly connected to the quartz pin 131 to prevent the quartz pin 131 from falling off; the connector moving mechanism is used to control the movement of the quartz pin connector, and further control the movement of the quartz pin 131 through the quartz pin connector; the moving mechanism control unit is used to control the connector moving mechanism, and control the connector moving mechanism to make corresponding actions according to the state in the single crystal furnace. For example, when the single crystal furnace needs to be charged, the moving mechanism control unit controls the quartz pin connector to move up through the connector moving mechanism, further drives the quartz pin 131 to move up, and finally is completely inside the guide tube 120, please refer to Figure 3 When the single crystal furnace is charged, the seed crystal rod 217 needs to be in contact with the liquid surface, or the necking, shouldering, shoulder turning, equal diameter growth and tailing processes need to be carried out. The moving mechanism control unit controls the quartz pin connector to move downward through the connector moving mechanism, further driving the quartz pin 131 to move downward, and finally protrudes from the bottom of the guide tube 120 and is fixed for measurement. Please refer to Figure 2 .

[0059] Preferably, if Figure 2As shown, the quartz pin connector is a rack connector 141, and the connector moving mechanism includes a gear 142 and a motor 143 that controls the rotation of the gear 142. It should be noted that the upper end of the rack connector 141 is a rack, and the lower end is a smooth strip structure, and only the smooth structure at the lower end enters the single crystal furnace, so that there is no gap between the rack connector 141 and the guide tube 120, ensuring that the single crystal furnace is a sealed space. The gear 142 and the rack connector 141 are meshed with each other, and the moving mechanism control unit is a motor control unit 144. The motor control unit 144 controls the rotation direction and speed of the motor 143, so that the gear 142 rotates, further driving the rack connector 141 to move, and the quartz pin 131 moves accordingly. For example, as Figure 2-3 As shown, when the single crystal furnace needs to be charged, the motor 143 drives the gear 142 to rotate counterclockwise, so that the rack connector 141 moves upward, driving the quartz pin 131 to completely enter the guide tube 120 upward to avoid collision; when the single crystal furnace is charged, it is necessary to make the seed crystal rod 217 contact with the liquid surface, or to carry out the necking, shouldering, shoulder rotation, equal diameter growth and tailing processes, the motor 143 drives the gear 142 to rotate clockwise, so that the rack connector 141 moves downward, driving the quartz pin 131 to enter the through hole 121 downward and protrude from the guide tube 120, and remain motionless to form a reflection for distance measurement. Since the quartz pin 131 protrudes from the guide tube 120 through the through hole 121 on the guide tube 120, the quartz pin 131 needs to be moved to the position of the through hole 121 when it is lowered for measurement. The rack connector 141 is made of a hard material, and the quartz pin 131 will not shake during the movement. The gear 142 rotates to drive the rack connector 141 to move, so that the rack connector 141 can maintain stable vertical movement, and further ensure that the quartz pin 131 is always in the same vertical line during the movement. It does not need to be aligned during the lowering process to enter the through hole 121, which is simple and convenient, improves the movement efficiency of the movable quartz pin device, and saves time cost.

[0060] Specifically, the quartz pin connector can also be a metal guide rope, the connector moving mechanism can also be a winding shaft connected to the motor, and the moving mechanism control unit can also be a switch or a motor driving chip. The switch or the motor driving chip controls the rotation direction and speed of the motor, thereby driving the winding shaft to rotate to tighten or lower the metal guide rope, and further causing the quartz pin 131 to be lowered or retracted; or, the quartz pin connector can also include a long rod and a sleeve, the long rod is fixedly connected to the quartz pin 131, and a thread is provided on the surface. The sleeve is sleeved on the outside of the long rod, and a thread that meshes with the long rod is provided inside, and is fixed on the guide tube 120. The connector moving mechanism is a motor, and the motor is connected to the long rod to drive it to rotate. The moving mechanism control unit is a switch or a motor driving chip. The switch or the motor driving chip controls the motor to rotate the long rod, so that the long rod is rotated out or retracted, and further drives the movement of the quartz pin 131; or, the retraction and release control component 140 can also be other structures that can control the rise or fall of the quartz pin 131, and the present application does not limit this.

[0061] Furthermore, the motor control unit 144 can be a switch, and the staff can determine whether it is necessary to measure the liquid level distance or add material by observing the situation of the single crystal furnace, and control the start and stop of the motor and the direction and speed of rotation through the switch; or, the motor control unit 144 can be a motor driving chip, which controls the start notification and the direction and speed of rotation of the motor by sending corresponding signals to the motor when the single crystal furnace is in different states.

[0062] It should be noted that, since the internal temperature of the single crystal furnace is extremely high during operation, in order to ensure that the rack connector 141 can work normally, the material of the rack connector 141 is a high temperature resistant material, for example, Teflon material.

[0063] Furthermore, a heat insulating layer 151 is provided below the motor 143 to prevent high temperature from affecting the normal operation of the motor 143. Specifically, an opening is provided on the heat insulating layer 151, so that the rack connector 141 can be connected to the quartz pin 131 through the heat insulating layer 151. In actual work, the heat insulating layer 151 can be a furnace cover 215, that is, the motor 143 and the gear 142 are arranged above the furnace cover 215, and the rack connector 141 extends downward into the interior of the guide tube 120 through the opening on the furnace cover 215 and is connected to the quartz pin 131. Since the furnace cover 215 can play a role in heat insulation, it is avoided to set up an additional heat insulating layer, reduce costs and make the movable quartz pin structure more reasonable.

[0064] Since during the measurement of the liquid level distance, if the quartz pin 131 shakes, it will affect the accuracy of the measurement, and further affect the quality of the single crystal silicon growth, the present application limits the position of the quartz pin 131 by a through hole 121 with a certain length, so as to increase stability and reduce shaking. Furthermore, the present application also provides a horizontal member 161, which is located at the position where the quartz pin 131 contacts the end of the rack connector 141. The horizontal member 161 is arranged outside the quartz pin 131, and its diameter is larger than that of the quartz pin 131. After the quartz pin 131 enters the through hole 121, the horizontal member 161 is supported above the through hole 121. When the quartz pin 131 is subjected to external forces and other factors, the horizontal member 161 can provide support to prevent the quartz pin 131 from shaking, so as to increase the stability of the quartz pin 131 and improve the accuracy of the liquid level distance measurement. At the same time, the horizontal member 161 can also prevent the quartz pin 131 from falling off.

[0065] Furthermore, a groove 122 is provided at the bottom of the guide tube 120 , and the through hole 121 is located in the groove 122 , so that when the quartz pin 131 is lowered, the quartz pin 131 enters the through hole 121 , and the horizontal member 161 fits into the groove 122 .

[0066] Furthermore, the material of the horizontal member 161 is graphite material.

[0067] Furthermore, if Figure 4 The figure shows a schematic diagram of the connection structure of the quartz pin and the quartz pin connector described in the embodiment of the present application. The lower end of the rack connector 141 is provided with an L-shaped slot 145, and the top of the quartz pin 131 is L-shaped and fits in the slot 145. The quartz pin 131 is embedded in the slot 145 of the rack connector 141, so that the rack connector 141 and the quartz pin 131 can be fixedly connected to prevent the quartz pin 131 from falling off. It should be noted that a notch can also be formed on the quartz pin 131, and a protrusion that can fit in with each other can be provided on the slot 145, or the slot 145 of the rack connector 141 can also be set to a T-shape or other shape that can fix the quartz pin 131, and the present application does not make specific restrictions here.

[0068] The movable quartz pin device of the present application realizes the movement of the quartz pin 131 through the retractable control component 140, so that the quartz pin 131 can be retracted and placed inside the guide tube 120 during the feeding process, so as to avoid the quartz pin 131 from being bumped and broken, and to avoid the quartz pin 131 from being damaged, and to prevent the silicon melt 212 from being contaminated, thereby improving the service life of the quartz pin 131 and the growth quality of the single crystal silicon. At the same time, the retractable control component includes a rack connector 141, a gear 142, a motor 143 and a motor control unit 144, which can move the quartz pin 131 on the same vertical line, so that when the quartz pin 131 is put down, the lower end can be protruded through the through hole 121 without alignment operation, which is convenient to operate and improves the moving efficiency of the quartz pin 131. The present application also provides a horizontal member 161 and a slot 145 on the rack connector 141 to prevent the quartz pin 131 from falling off, and the horizontal member 161 can also reduce the shaking of the quartz pin 131, further improving the measurement accuracy of the liquid level distance, which is beneficial to the practical application of the single crystal furnace equipment.

[0069] This embodiment also provides a liquid level distance measurement system 100, including:

[0070] The guide tube 120 is equipped with the aforementioned movable quartz pin device for auxiliary measurement. The specific structure of the movable quartz pin device is as described above and will not be described here. When the liquid level distance measurement system 100 is used to measure the distance between the guide tube 120 and the silicon melt 212 in the single crystal furnace, the guide tube 120 is arranged above the crucible 213 in the single crystal furnace and is also used to introduce argon gas.

[0071] The camera 111 is arranged outside the guide tube 120 and is used to photograph the quartz pin 131 and its reflection. When the liquid level distance measurement system 100 is used to measure the distance between the guide tube 120 and the silicon melt 212 in the single crystal furnace, the camera 111 is arranged outside the single crystal furnace and can capture the quartz pin 131 and its reflection through the observation window 112 on the single crystal furnace for photographing.

[0072] The image processor 113 is connected to the camera 111. The image captured by the camera 111 is uploaded to the image processor 113, and the distance between the guide tube 120 and the liquid surface of the silicon melt 212 is obtained by the reflection method. Specifically, the image processor 113 calculates the distance between the guide tube 120 and the liquid surface of the silicon melt 212 by proportionally amplifying the pixel distance between the quartz pin 131 and the reflection captured by the camera 111, so as to realize the positioning of the liquid surface of the silicon melt 212 and the precise control of the distance from the guide tube 120 to the liquid surface of the silicon melt 212.

[0073] The present application measures the distance between the guide tube 120 and the liquid surface of the silicon melt 212 through the liquid surface distance measurement system 100. The liquid surface distance measurement system 100 adopts the reflection method, and the quartz pin 131 and its reflection are photographed by the camera 111 outside the single crystal furnace observation window 112, and uploaded to the image processor 113, and the image processor 113 can process and obtain the distance between the guide tube 120 and the liquid surface of the silicon melt 212. Based on this, the present application can obtain an accurate liquid surface distance. Since the liquid surface distance is extremely important in the growth process of single crystal silicon, the liquid surface distance measurement system 100 of the present application can greatly improve the quality of the silicon crystal rod 211 produced. At the same time, the quartz pin 131 in the present application can be moved by the retractable control component 140, and retracted into the guide tube 120 when measurement is not required, so as to avoid being bumped and scratched, thereby improving the service life of the quartz pin 131, and also avoiding the contamination of the silicon melt 212, and improving the production quality of the silicon crystal rod 211.

[0074] The descriptions of the processes or structures corresponding to the above-mentioned figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0075] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A movable quartz pin device, characterized in that: It includes a quartz pin and a retractable control assembly; the quartz pin passes through the bottom of the guide tube through the through hole at the bottom of the guide tube, and when the quartz pin device is in a measuring state, the lower end of the quartz pin protrudes out of the bottom of the guide tube; The retractable and extendable control assembly comprises a quartz pin connector, a connector moving mechanism and a moving mechanism control unit, and the quartz pin connector is fixedly connected to the upper end of the quartz pin.

2. The device according to claim 1, characterized in that The quartz pin connector is a rack connector, the upper end of the rack connector is a rack, and the lower end is a smooth strip structure. The connector moving mechanism includes a gear and a motor for controlling the rotation of the gear, and the gear and the rack are meshed with each other.

3. The device according to claim 1, characterized in that The moving mechanism control unit is a switch or a motor driving chip.

4. The device according to claim 2, characterized in that A heat insulation layer is arranged below the motor, an opening is arranged on the heat insulation layer, and the rack connecting member passes through the opening and is fixedly connected with the quartz pin.

5. The device according to claim 2, characterized in that The rack connecting piece is made of high temperature resistant material.

6. The device according to claim 1, characterized in that The lower end of the quartz pin connector is provided with a slot, and the upper end of the quartz pin is embedded in the slot and fixedly connected to the lower end of the quartz pin connector.

7. The device according to claim 1, characterized in that A horizontal piece is provided at the junction of the quartz pin connecting piece and the outer portion of the quartz pin. The horizontal piece is fixedly connected to the quartz pin, and the diameter of the horizontal piece is greater than the diameter of the quartz pin.

8. The device according to claim 7, characterized in that A groove is provided at the bottom of the guide tube, the through hole is located in the groove, and the horizontal member fits into the groove when the quartz pin device is in a measuring state.

9. The device according to any one of claims 7 or 8, characterized in that The horizontal member is made of graphite.

10. A liquid level distance measurement system, characterized in that: include: A guide tube, equipped with a movable quartz pin device as described in any one of claims 1 to 9; A camera, which is arranged outside the guide tube and is used to photograph the quartz pins and the reflection of the quartz pins in the movable quartz pin device; An image processor is connected to the camera.

Images