Silicon rod resistivity on-line measurement system

Abstract

The utility model relates to a silicon rod resistivity on-line measurement system, and the system comprises an electromagnetic induction measurement unit which comprises an excitation mechanism for applying an alternating magnetic field to a silicon rod and an induction mechanism for inducing the variable magnetic field of the silicon rod to form an induction current; the processing unit is electrically connected with the electromagnetic induction measuring unit; the positioning device comprises a displacement mechanism which is connected with the electromagnetic induction measuring unit and is used for adjusting the position of the electromagnetic induction measuring unit; and the distance measuring unit is arranged on the displacement mechanism and is used for measuring the distance between the electromagnetic induction measuring unit and a reference substance in the single crystal furnace. According to the scheme, on-line non-contact measurement of the resistivity in the silicon rod crystal pulling process can be achieved, the purpose of monitoring the resistivity of the silicon rod in real time is achieved, and the contact damage risk of the silicon rod is avoided.

Description

Technical Field

[0001] This application relates to the field of silicon rod testing technology, and in particular to an online system for measuring the resistivity of silicon rods. Background Technology

[0002] In the production of single-crystal silicon rods, resistivity is a key parameter for measuring crystal quality. Current technologies mostly employ contact probe methods, which require measurement after the silicon rod has cooled, resulting in the following drawbacks:

[0003] 1. Inability to monitor in real time: The cooling process is time-consuming, causing production interruptions and making it difficult to adjust process parameters online.

[0004] 2. Risk of physical damage: Probe contact may scratch the surface of the silicon rod, affecting the quality of the finished product.

[0005] 3. Poor environmental adaptability: The high temperature and high vacuum environment of the single crystal furnace poses a challenge to the stability of contact equipment. Utility Model Content

[0006] Based on this, the present invention provides an online resistivity measurement system for silicon rods to solve the problems of traditional single-crystal silicon rod resistivity testing devices being unable to measure the resistivity of silicon rods in real time, resulting in long measurement cycles and difficulty in adjusting crystal pulling process parameters online.

[0007] This utility model provides an online resistivity measurement system for silicon rods, comprising:

[0008] An electromagnetic induction measurement unit is disposed in a single crystal furnace and located on the pulling path of a silicon rod. The electromagnetic induction measurement unit includes an excitation mechanism that applies an alternating magnetic field to the silicon rod and a sensing mechanism that senses the changing magnetic field of the silicon rod to generate an induced current.

[0009] The processing unit is electrically connected to the electromagnetic induction measurement unit;

[0010] Positioning device, including:

[0011] A displacement mechanism, which is connected to the electromagnetic induction measuring unit, is used to adjust the position of the electromagnetic induction measuring unit;

[0012] A ranging unit is mounted on the displacement mechanism and is used to measure the distance between the electromagnetic induction measuring unit and the reference object inside the single crystal furnace.

[0013] In one embodiment, the excitation mechanism includes an excitation coil and a high-frequency signal generator electrically connected to the excitation coil;

[0014] The sensing mechanism includes an induction coil disposed opposite to the excitation coil and a magnetic field sensor disposed on the induction coil.

[0015] In one embodiment, the induction coil and the excitation coil are coaxially disposed in a single crystal furnace;

[0016] And / or, the induction coil is located above the excitation coil.

[0017] In one embodiment, the displacement mechanism includes:

[0018] A support member for mounting the electromagnetic induction measuring unit and being horizontally aligned with the reference object;

[0019] An adjusting component, connected between the support and the furnace wall of the single crystal furnace, is used to adjust the horizontal position of the support to adjust the horizontal distance between the electromagnetic induction measuring unit and the reference object.

[0020] In one embodiment, the support includes two opposing support plates, and the adjustment element is provided between each support plate and the furnace wall of the single crystal furnace;

[0021] Both the excitation coil and the induction coil are wound around the two support plates.

[0022] In one embodiment, at least one positioning post is provided on the furnace wall of the single crystal furnace at the position corresponding to each of the support plates;

[0023] The adjusting component includes an adjusting screw threaded between the support plate and the positioning post.

[0024] In one embodiment, the reference object is horizontally positioned relative to the electromagnetic induction measurement unit within the single crystal furnace;

[0025] The ranging unit includes at least one optical ranging sensor, which is disposed on the support plate and faces the reference object along the displacement direction of the support plate. The displacement direction of the support plate is horizontal, moving towards or away from the reference object.

[0026] In one embodiment, the processing unit includes:

[0027] The signal processing module is connected to the electromagnetic induction measurement unit.

[0028] The data acquisition module is connected to the signal processing module via a signal connection.

[0029] The data processing module is signal-connected to the data acquisition module.

[0030] In one embodiment, the online resistivity measurement system for silicon rods further includes a temperature sensor that is signal-connected to the processing unit. The temperature sensor is located inside the single crystal furnace, and its measuring end points towards the silicon rod.

[0031] In one embodiment, the silicon rod resistivity online measurement system further includes a control unit electrically connected to the electromagnetic induction measurement unit, the processing unit, and the temperature sensor.

[0032] Compared with the prior art, this utility model has at least the following beneficial effects:

[0033] This online resistivity measurement system for silicon rods places an electromagnetic induction measurement unit along the lifting path of the silicon rod. As the rod is pulled up, it passes through the electromagnetic induction measurement unit, which applies an alternating magnetic field to the rod and generates an electrical signal related to its resistivity. This signal is then processed by a processing unit to output resistivity data. This achieves non-contact online testing of the silicon rod's resistivity during the lifting process, enabling real-time monitoring of the rod's resistivity while avoiding the risk of contact damage.

[0034] In addition, this online measurement system, through the cooperation of the ranging unit and the displacement mechanism, can accurately position the electromagnetic induction measurement unit in the single crystal furnace, thereby maintaining the accuracy of the relative position between the silicon rod and the electromagnetic induction measurement unit, ensuring the stability and consistency of the position during the measurement process, maintaining the stability of the measurement environment, and thus improving the reliability of the measurement. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of an online silicon rod resistivity measurement system in one embodiment;

[0036] Figure 2 This is a partial structural schematic diagram of an online silicon rod resistivity measurement system in one embodiment;

[0037] Figure 3 This is a schematic diagram of the processing unit of an online silicon rod resistivity measurement system in one embodiment;

[0038] Figure 4 This is a schematic diagram of the structure of a single crystal furnace.

[0039] The reference numerals in the accompanying drawings include: electromagnetic induction measurement unit 100, excitation coil 110, induction coil 120, magnetic field sensor 130, high-frequency signal generator 140, processing unit 200, signal processing module 210, data acquisition module 220, data processing module 230, positioning device 300, displacement mechanism 310, support component 311, adjusting component 312, ranging unit 320, positioning column 330, single crystal furnace 400, upper furnace chamber 410, temperature sensor 500, operation panel 600, and sealing device 700. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0041] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model.

[0042] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this utility model can be implemented. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0043] The orientations or positional relationships indicated by terms such as "upper," "lower," "left," "right," "middle," "longitudinal," "transverse," "horizontal," "inner," "outer," "radial," and "circumferential" used in this specification are based on the orientations or positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] As described in the background section, traditional resistivity testing of monocrystalline silicon rods often employs contact probe methods, which require measurement after the silicon rod has cooled down. This makes real-time monitoring impossible, leading to production interruptions and making it difficult to adjust process parameters online. Furthermore, probe contact may scratch the surface of the silicon rod, posing a risk of physical damage and affecting the quality of the finished product.

[0045] To address this, this utility model provides an online resistivity measurement system for silicon rods, comprising:

[0046] The electromagnetic induction measurement unit 100 is disposed in the single crystal furnace 400 and located on the pulling path of the silicon rod. The electromagnetic induction measurement unit 100 includes an excitation mechanism that applies an alternating magnetic field to the silicon rod and a sensing mechanism that senses the changing magnetic field of the silicon rod and forms an induced current.

[0047] The processing unit 200 is electrically connected to the electromagnetic induction measurement unit 100;

[0048] Positioning device 300, including:

[0049] The displacement mechanism 310 is connected to the electromagnetic induction measuring unit 100 and is used to adjust the position of the electromagnetic induction measuring unit 100.

[0050] The ranging unit 320 is mounted on the displacement mechanism 310 and is used to measure the distance between the electromagnetic induction measuring unit 100 and the reference object inside the single crystal furnace 400.

[0051] The online measurement system provided in this embodiment of the utility model sets the electromagnetic induction measurement unit 100 on the lifting path of the silicon rod, so that the silicon rod can pass through the electromagnetic induction measurement unit 100 when it is lifted. The excitation mechanism applies an alternating magnetic field to the silicon rod. The alternating magnetic field penetrates the silicon rod and induces eddy currents inside the silicon rod. The eddy currents generate a reverse magnetic field. The reverse magnetic field partially cancels out the alternating magnetic field and finally generates a composite magnetic field after cancellation around the silicon rod. Then, the sensing mechanism receives the changing composite magnetic field and generates an induced current. The processing unit 200 processes the induced current and finally outputs resistivity data, thereby obtaining the resistivity of the silicon rod.

[0052] Based on the above, this online silicon rod resistivity measurement system can be installed inside a single crystal furnace 400 to achieve non-contact online testing of silicon rod resistivity during the silicon rod pulling process, thereby achieving real-time monitoring of silicon rod resistivity and avoiding the risk of contact damage to the silicon rod.

[0053] In addition, through the cooperation of the ranging unit 320 and the displacement mechanism 310, this online measurement system can accurately position the electromagnetic induction measurement unit 100 in the single crystal furnace 400, thereby maintaining the accuracy of the relative position between the silicon rod and the electromagnetic induction measurement unit 100, ensuring the stability and consistency of the position during the measurement process, maintaining the stability of the measurement environment, and thus improving the reliability of the measurement.

[0054] The online resistivity measurement system for silicon rods provided in this embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0055] according to Figure 1An exemplary embodiment of the silicon rod resistivity online measurement system of at least one embodiment of the present invention is shown. The silicon rod resistivity online measurement system includes: an electromagnetic induction measurement unit 100, a processing unit 200, a control unit, and a positioning device 300.

[0056] The electromagnetic induction measurement unit 100 is disposed on the lifting path of the silicon rod and is used to apply an alternating magnetic field to the silicon rod and generate an electrical signal related to resistivity based on the magnetic field change caused by the silicon rod.

[0057] In this embodiment, the silicon rod pulling path can be understood as the path taken by the silicon rod during the process of pulling monocrystalline or polycrystalline silicon into a silicon rod. For example, see... Figure 4 Based on the existing crystal pulling operation of the single crystal furnace 400, the pulling path of the silicon rod refers to the path from the crucible (not shown) of the single crystal furnace 400 to the upper furnace chamber 410. Correspondingly, the electromagnetic induction measurement unit 100 being disposed on the pulling path of the silicon rod can be understood as being disposed between the crucible of the single crystal furnace 400 and the top of the upper furnace chamber 410, ensuring that the silicon rod can pass through the electromagnetic induction measurement unit 100.

[0058] See Figure 1 In this embodiment, preferably, the electromagnetic induction measurement unit 100 is disposed inside the upper furnace chamber 410. This not only ensures that the silicon rod is formed to the same diameter when tested by the electromagnetic induction measurement unit 100, meeting the measurement standards and ensuring the effectiveness of the measurement, but also increases the distance between the electromagnetic induction measurement unit 100 and the lower furnace chamber, avoiding the adverse effects of the high temperature of the lower furnace chamber on the electromagnetic induction measurement unit 100 and ensuring measurement stability.

[0059] Specifically, in this embodiment, the electromagnetic induction measurement unit 100 mainly includes an excitation mechanism and a sensing mechanism.

[0060] The excitation mechanism is used to apply an alternating magnetic field to the silicon rod. For example, see... Figure 2 The excitation mechanism includes an excitation coil 110 and a high-frequency signal generator 140. The excitation coil 110 is located inside the single crystal furnace 400 and on the pulling path of the silicon rod, meaning the silicon rod can pass through the excitation coil 110 during the pulling process. The high-frequency signal generator 140 is located outside the single crystal furnace 400 and is electrically connected to the excitation coil 110. During operation, the high-frequency signal generator 140 generates a high-frequency alternating current, which is supplied to the excitation coil 110 to generate an alternating magnetic field. This alternating magnetic field induces eddy currents inside the silicon rod, which generate a reverse magnetic field that partially cancels out the alternating magnetic field, ultimately generating a composite magnetic field around the silicon rod, providing the basis for the sensing mechanism.

[0061] In this embodiment, to ensure that the excitation coil 110 can work stably in a high-temperature environment and effectively transmit the magnetic field, the excitation coil 110 is made of a high-temperature resistant conductive material, such as silver-plated copper wire or nickel-chromium alloy wire.

[0062] In this embodiment, the diameter of the excitation coil 110 is determined according to the diameter of the single crystal furnace 400 at the installation location. For example, corresponding to the embodiment where the excitation coil 110 is installed in the upper furnace chamber 410, the diameter of the excitation coil 110 should be slightly smaller than the inner diameter of the upper furnace chamber 410 to ensure that it can be concentrically arranged inside the upper furnace chamber 410 and can also match the passage of silicon rods of different diameters.

[0063] It should be understood that the eddy current intensity of the silicon rod caused by the excitation mechanism is mainly related to the resistivity of the silicon rod. Specifically, the smaller the resistivity, the greater the eddy current intensity. The eddy current intensity is also related to the strength of the synthetic magnetic field. Therefore, the resistivity of the silicon rod can be obtained by detecting the strength of the synthetic magnetic field.

[0064] Based on this, in this embodiment, the strength of the synthetic magnetic field is measured by a sensing mechanism and converted into an electrical signal related to resistivity, so as to provide a basis for resistivity data output.

[0065] For details, see Figure 2 The sensing mechanism includes an induction coil 120 and a magnetic field sensor 130.

[0066] The induction coil 120 is disposed inside the single crystal furnace 400 and located on the pulling path of the silicon rod, meaning the silicon rod can pass through the induction coil 120 during the pulling process. The induction coil 120 is positioned opposite the excitation coil 110, for example, the induction coil 120 is positioned above the excitation coil 110. Thus, the induction coil 120 can receive the synthesized magnetic field and generate an induced current, which is then supplied to the processing unit 200.

[0067] A magnetic field sensor 130 is mounted on an induction coil 120 and is used to measure the strength and changes of a magnetic field. Specifically, the magnetic field sensor 130 can capture the magnetic field strength and then provide it to the processing unit 200. The magnetic field sensor 130 can be a Hall effect sensor or a fiber optic magnetic field sensor.

[0068] Based on the above sensing mechanism, the induced current generated by the magnetic field is captured by the induction coil 120, and the magnetic field strength is directly quantified by the magnetic field sensor 130. The two work together to achieve accurate quantification of resistivity.

[0069] In this embodiment, to ensure that the induction coil 120 can operate stably in a high-temperature environment and effectively sense the synthesized magnetic field, the induction coil 120 is also supported by a high-temperature resistant conductive material, such as silver-plated copper wire or nickel-chromium alloy wire. To ensure the stable operation of the magnetic field sensor 130, the magnetic field sensor 130 is wrapped with a high-temperature resistant material, such as high-temperature ceramic, to insulate it from external high temperatures.

[0070] In this embodiment, the diameter of the induction coil 120 is determined according to the diameter of the single crystal furnace 400 at the installation location. For example, corresponding to the embodiment where the induction coil 120 is installed in the upper furnace chamber 410, the diameter of the induction coil 120 should be slightly smaller than the inner diameter of the upper furnace chamber 410 to ensure that it can be concentrically arranged inside the upper furnace chamber 410 and can also accommodate the passage of silicon rods of different diameters. Specifically, the diameter of the induction coil 120 can be the same as the diameter of the excitation coil 110.

[0071] Furthermore, in this embodiment, the induction coil 120 and the excitation coil 110 are arranged coaxially, so that the silicon rod can be synchronously located at the center position of the induction coil 120 and the excitation coil 110, ensuring the accuracy of detection.

[0072] In this embodiment, the positioning device 300 is used to ensure the accurate relative position of the silicon rod with the excitation coil 110 and the induction coil 120, to ensure the stable position of the silicon rod during the measurement process, and to avoid measurement errors caused by position changes.

[0073] For details, see Figure 2 The positioning device 300 includes a ranging unit 320 and a displacement mechanism 310.

[0074] The displacement mechanism 310 is connected to the electromagnetic induction measurement unit 100 and is used to adjust the position of the electromagnetic induction measurement unit 100.

[0075] For example, see Figure 2 The displacement mechanism 310 includes a support member 311 and an adjusting member 312. The support member 311 is used to mount the electromagnetic induction measurement unit 100, i.e., to mount the induction coil 120 and the excitation coil 110, to ensure the positioning support of the induction coil 120 and the excitation coil 110 and to ensure that they are horizontally relative to the reference object. The adjusting member 312 is connected between the support member 311 and the furnace wall of the single crystal furnace 400, and is used to adjust the horizontal position of the support member 311, thereby adjusting the distance between the electromagnetic induction measurement unit 100 and the reference object, so as to adjust the electromagnetic induction measurement unit 100 to the specified position and ensure the accuracy of the relative position between the electromagnetic induction measurement unit 100 and the silicon rod.

[0076] For details, see Figure 2The support member 311 includes two opposing support plates. Each support plate is provided with an adjustment member 312 between itself and the furnace wall of the single crystal furnace 400. The two support plates are arranged opposite each other along the diameter direction of the upper furnace chamber 410. The induction coil 120 and the excitation coil 110 are both wound on the two support plates and arranged horizontally. This allows the induction coil 120 and the excitation coil 110 to form a whole with the two support plates. When the positions of the two support plates are adjusted synchronously, the positions of the induction coil 120 and the excitation coil 110 can be adjusted.

[0077] Furthermore, to improve the compatibility between the support plate and the induction coil 120 and the excitation coil 110, the outer surface of the support plate can be an arc-shaped surface that adapts to the inner ring of the induction coil 120 and the excitation coil 110, ensuring the fit between the support plate and the induction coil 120 and the excitation coil 110.

[0078] Each support plate is equipped with an adjustment component 312 between itself and the furnace wall of the single crystal furnace 400. The two support plates can be adjusted synchronously through the adjustment components 312 on both sides, which is more conducive to the adjustment of the induction coil 120 and the excitation coil 110.

[0079] For details, see Figure 2 On the furnace wall of the single crystal furnace 400, at least one positioning post 330 is raised at the position corresponding to each support plate. Figure 2 An exemplary embodiment is shown, comprising a support plate corresponding to two positioning posts 330. The adjusting member 312 includes an adjusting screw threaded between the support plate and the positioning posts 330, see [link to relevant documentation]. Figure 2 Each support plate is connected to two positioning posts 330 via two adjusting screws. This configuration allows for adjustment of the horizontal position of the support plate by rotating the adjusting screws, thereby adjusting the horizontal position of the induction coil 120 and the excitation coil 110.

[0080] Of course, in other embodiments, the adjusting member 312 can also be a linear adjusting mechanism disposed outside the single crystal furnace 400. For example, the adjusting member 312 can be a gear and rack mechanism, with a push rod connected to the rack that can extend into the single crystal furnace 400 and connect to the support plate. The support plate can be adjusted by rotating the gear. Alternatively, the adjusting member 312 can be a cylinder or a hydraulic cylinder. By inserting the piston rod of the cylinder or hydraulic cylinder into the single crystal furnace 400 and connecting it to the support plate, the support plate can be adjusted by the cylinder or hydraulic cylinder.

[0081] In this embodiment, the ranging unit 320 is used to measure the distance between the electromagnetic induction measuring unit 100 and the reference object inside the single crystal furnace 400. This distance is a horizontal distance, in order to confirm whether the electromagnetic induction measuring unit 100 is adjusted in place, thereby confirming whether the positioning position of the electromagnetic induction measuring unit 100 is accurate.

[0082] The reference object is horizontally opposite to the electromagnetic induction measurement unit 100 inside the single crystal furnace 400; the ranging unit 320 includes at least one optical ranging sensor, which is disposed on the support plate and faces the reference object along the displacement direction of the support plate, which is horizontal and either close to or away from the reference object.

[0083] Specifically, in this embodiment, the accuracy of the positioning of the electromagnetic induction measurement unit 100 is mainly determined by whether the induction coil 120 and the excitation coil 110 are coaxial with the upper furnace chamber 410. That is, when the induction coil 120 and the excitation coil 110 are coaxial with the upper furnace chamber 410, it can be said that the induction coil 120 and the excitation coil 110 are accurately positioned. This ensures that the silicon rod lifted to the designated position is exactly located at the center of the induction coil 120 and the excitation coil 110, thus ensuring the accuracy of the test.

[0084] Based on this, the reference object can be a reference piece set inside the single crystal furnace 400 and horizontally aligned with the induction coil 120 and the excitation coil 110. In this way, the horizontal position of the induction coil 120 and the excitation coil 110 can be adjusted by adjusting the horizontal distance between the electromagnetic induction measuring unit 100 and the reference object until the center of the induction coil 120 and the excitation coil 110 are coaxial with the upper furnace chamber 410, thus completing the positioning.

[0085] For example, the reference object can be an internal component or structure of the single crystal furnace 400 itself, such as a seed crystal rope or a furnace wall surface. The seed crystal rope is the pulling rope used for crystal pulling and silicon rod pulling in the single crystal furnace 400, and it is usually located at the center of the furnace chamber. The furnace wall surface here refers to the furnace wall surface of the upper furnace chamber 410, which is usually a cylindrical surface coaxial with the seed crystal rope. Thus, using the seed crystal rope or the furnace wall surface as a positioning reference, it is possible to accurately determine whether the induction coil 120 and the excitation coil 110 are concentric with the upper furnace chamber 410, providing a basis for confirming whether the induction coil 120 and the excitation coil 110 are in their designated positions.

[0086] In this embodiment, the ranging unit 320 includes at least one optical ranging sensor. Preferably, there are two optical ranging sensors, which are respectively disposed on two support plates. The two optical ranging sensors are simultaneously facing the seed crystal rope or the furnace wall along the displacement direction of the support plates. Taking the simultaneous facing of the seed crystal rope as an example, when the two optical ranging sensors measure that the distance between the two support plates and the seed crystal rope is equal, it indicates that the induction coil 120 and the excitation coil 110 are located at the coaxial position with the seed crystal rope. At this time, the positioning position of the induction coil 120 and the excitation coil 110 is accurate.

[0087] Based on the above, through the cooperation of the ranging unit 320 and the displacement mechanism 310, the electromagnetic induction measuring unit 100 can be precisely positioned in the single crystal furnace 400, thereby maintaining the accuracy of the relative position between the silicon rod and the electromagnetic induction measuring unit 100, ensuring the stability and consistency of the position during the measurement process, maintaining the stability of the measurement environment, and thus improving the reliability of the measurement.

[0088] In this embodiment, the processing unit 200 is electrically connected to the electromagnetic induction measurement unit 100, and is used to receive and process the signal from the magnetic field sensor 130 to output resistivity data.

[0089] For details, see Figure 3 The processing unit 200 includes a signal processing module 210, a data acquisition module 220, and a data processing module 230.

[0090] The signal processing module 210 is connected to the electromagnetic induction measurement unit 100 and is used to process the electrical signals transmitted from the induction coil 120 and the magnetic field sensor 130. The processing includes signal amplification, signal filtering and signal digitization to convert the electrical signals into accurate and processable digital signals, providing a basis for subsequent data acquisition and analysis.

[0091] For example, the signal processing module 210 may specifically include an amplifier, a filter, and an analog-to-digital converter. The amplifier amplifies the transmitted weak signal to ensure sufficient signal strength for subsequent processing; the filter filters the amplified signal to remove noise and interference and extract the effective signal; and the analog-to-digital converter converts the extracted signal into a digital signal.

[0092] The data acquisition module 220 is connected to the signal processing module 210 and is used to acquire the processed signal into a computer or data recording device to provide a basis for data analysis.

[0093] For example, the data acquisition module 220 may include a high-speed data acquisition card and a memory. The high-speed data acquisition card acquires data signals in real time, and the memory stores the signals, enabling real-time monitoring and storage of the measurement data, which facilitates subsequent analysis and processing.

[0094] The data processing module 230 is connected to the data acquisition module 220 by signal and is used to perform preliminary analysis on the data acquired by the data acquisition module 220 to calculate the instantaneous resistivity of the silicon rod.

[0095] During the pulling process and the stabilization process at 400°C in the single crystal furnace, the silicon rod will experience temperature changes. Specifically, the temperature of the silicon rod will gradually decrease. Since the resistivity of the silicon rod changes with temperature, there will be significant differences in the resistivity measured at different time points, which will lead to measurement errors in resistivity.

[0096] Based on this, in this embodiment, the online measurement system is also equipped with a temperature compensation unit, which is electrically connected to the processing unit 200 and the control unit. The temperature compensation unit is used to monitor the temperature of the silicon rod and feed it back to the processing unit 200 and the control unit, so that the processing unit 200 can correct the resistivity measurement error caused by the temperature change of the silicon rod according to the real-time temperature data of the silicon rod, thereby improving the measurement accuracy.

[0097] Specifically, in this embodiment, the temperature compensation unit includes a temperature sensor 500, which is signal-connected to the processing unit 200. See also... Figure 2 The temperature sensor 500 is installed inside the single crystal furnace 400, such as on a support plate, with its measuring end horizontally pointing towards the center of the upper furnace chamber 410. This ensures that during testing, its measuring end is horizontally aligned with the silicon rod, allowing for the measurement of the silicon rod's temperature. A high-precision thermocouple or infrared thermometer can be used. During operation, the temperature sensor 500 transmits the measured silicon rod temperature data to the processing unit 200 for resistivity compensation calculations to correct errors caused by temperature changes. The compensation calculation method is determined based on the correlation between temperature and resistivity, which will not be elaborated here.

[0098] In this embodiment, the online measurement system also includes a control unit, which is electrically connected to the electromagnetic induction measurement unit 100, the processing unit 200, the temperature sensor 500, etc., and is used to coordinate and control the operation of each component.

[0099] Specifically, the control unit is responsible for controlling the frequency, amplitude, and phase of the excitation current, as well as the time and interval of data acquisition. It sets and adjusts parameters through a computer program, using PID control or other control algorithms to achieve precise control, coordinate the work of various components, and ensure system stability and measurement accuracy. The control unit can be a programmable logic controller (PLC).

[0100] See Figure 3 In this embodiment, the measurement system also includes an operation panel 600, which is the interface for the operator to interact with the control unit. It typically includes a touch screen, buttons, etc., and is used for parameter setting and monitoring.

[0101] Additionally, it should be noted that since the power and signal lines of the induction coil 120, excitation coil 110, and temperature sensor 500 are all led out from the inside of the single crystal furnace 400 to the outside, the furnace wall of the single crystal furnace 400 is provided with wire holes, and a sealing device 700 is provided at the wire holes. The sealing device 700 can be a sealing ring, sealing ring, etc. In this way, the sealing device 700 can ensure the stability of the internal environment of the single crystal furnace 400 and reduce the impact on crystal pulling.

[0102] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An online resistivity measurement system for silicon rods, characterized in that, include: An electromagnetic induction measurement unit (100) is disposed in a single crystal furnace (400) and located on the pulling path of the silicon rod. The electromagnetic induction measurement unit (100) includes an excitation mechanism that applies an alternating magnetic field to the silicon rod and a sensing mechanism that senses the changing magnetic field of the silicon rod and forms an induced current. The processing unit (200) is electrically connected to the electromagnetic induction measurement unit (100); Positioning device (300), comprising: A displacement mechanism (310) is connected to the electromagnetic induction measuring unit (100) and is used to adjust the position of the electromagnetic induction measuring unit (100); A ranging unit (320) is disposed on the displacement mechanism (310) and is used to measure the distance between the electromagnetic induction measuring unit (100) and the reference object in the single crystal furnace (400).

2. The online resistivity measurement system for silicon rods according to claim 1, characterized in that, The excitation mechanism includes an excitation coil (110) and a high-frequency signal generator (140) electrically connected to the excitation coil (110); The sensing mechanism includes an induction coil (120) disposed opposite to the excitation coil (110) and a magnetic field sensor (130) disposed on the induction coil (120).

3. The online resistivity measurement system for silicon rods according to claim 2, characterized in that, The induction coil (120) and the excitation coil (110) are coaxially arranged in the single crystal furnace (400); And / or, the induction coil (120) is located above the excitation coil (110).

4. The online resistivity measurement system for silicon rods according to claim 2, characterized in that, The displacement mechanism (310) includes: A support member (311) is used to mount the electromagnetic induction measuring unit (100) and is horizontally opposite the reference object; An adjusting member (312) is connected between the support member (311) and the furnace wall of the single crystal furnace (400) for adjusting the horizontal position of the support member (311).

5. The online resistivity measurement system for silicon rods according to claim 4, characterized in that, The support member (311) includes two opposing support plates, and each support plate is provided with an adjustment member (312) between itself and the furnace wall of the single crystal furnace (400). Both the excitation coil (110) and the induction coil (120) are wound around the two support plates.

6. The online resistivity measurement system for silicon rods according to claim 5, characterized in that, At least one positioning post (330) is provided on the furnace wall of the single crystal furnace (400) at the position corresponding to each of the support plates; The adjusting component (312) includes an adjusting screw threaded between the support plate and the positioning post (330).

7. The online resistivity measurement system for silicon rods according to claim 5, characterized in that, The reference object is horizontally opposite the electromagnetic induction measurement unit (100) inside the single crystal furnace (400); The ranging unit (320) includes at least one optical ranging sensor, which is disposed on the support plate and faces the reference object along the displacement direction of the support plate. The displacement direction of the support plate is horizontal, either approaching or moving away from the reference object.

8. The online resistivity measurement system for silicon rods according to claim 1, characterized in that, The processing unit (200) includes: The signal processing module (210) is connected to the electromagnetic induction measurement unit (100) via signal processing. The data acquisition module (220) is connected to the signal processing module (210) via a signal. The data processing module (230) is signal-connected to the data acquisition module (220).

9. The online resistivity measurement system for silicon rods according to claim 8, characterized in that, The online resistivity measurement system for silicon rods also includes a temperature sensor (500) that is signal-connected to the processing unit (200). The temperature sensor (500) is located inside the single crystal furnace (400), and its temperature measuring end points towards the silicon rod.

10. The online resistivity measurement system for silicon rods according to claim 9, characterized in that, The silicon rod resistivity online measurement system also includes a control unit, which is electrically connected to the electromagnetic induction measurement unit (100), the processing unit (200), and the temperature sensor (500).

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