Multi-region in-situ online detection method and device

Abstract

The invention provides a multi-region in-situ online detection method and device, and the method comprises the steps: enabling a plurality of probes to be opposite to a tray in epitaxial growth equipment before an epitaxial technology; in the epitaxial process, a plurality of probes are adopted to obtain a reflection signal and an infrared radiation signal of the surface of the wafer on the tray; processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve which change in real time; and after the epitaxial process is completed, judging the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment according to the reflectivity curve and the temperature curve. According to the invention, the reflection signals and the temperature signals of multiple areas on the surface of the wafer are obtained by adopting the arrangement of multiple probes, and the reflectivity curve and the temperature curve are obtained, so that the accuracy of overall detection of the epitaxial layer of the wafer in epitaxial growth equipment is improved, the yield problem of single-area detection is effectively reduced, and the reliability of the epitaxial growth process is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor epitaxial growth equipment, and in particular to a multi-region in-situ online detection method and device thereof. Background Art

[0002] Epitaxial growth is a technique for growing a new single-crystal layer along its crystal orientation on a single-crystal substrate. Its core principle is to achieve homoepitaxial or heteroepitaxial growth by matching the lattice constants of the materials. In semiconductor device manufacturing, epitaxial growth of different film materials is used to enhance the electrical characteristics of transistors, thereby achieving higher drive currents, higher switching frequencies, and superior chip performance.

[0003] In epitaxial growth equipment, wafer substrates cannot be placed directly on metal for epitaxial deposition. This involves numerous influencing factors, including gas flow direction (horizontal or vertical), temperature, pressure, fixation, and loose contaminants. Therefore, a graphite disk base is required. The substrate is then placed on a tray above the disk, and the epitaxial growth process is then used for thin film deposition. The graphite disk is heated using three main heating methods: high-frequency induction heating, infrared radiation heating, and resistance heating. However, the heating temperature of the disk requires strict precision control and heating uniformity monitoring. Therefore, real-time monitoring of temperature and reflectivity parameters at multiple locations on the wafer surface is necessary to confirm any abnormalities in the growth process. Existing technology typically uses a thermometer to scan the graphite disk through a glass window. The disk rotates at a constant speed, and the thermometer probe is moved gradually from the center to the edge of the disk to measure the temperature distribution across the disk.

[0004] Existing in-situ inspection equipment cannot monitor the epitaxial growth of multiple regions, instead using only a single probe to inspect a single area. This test result does not accurately reflect the overall condition of the epitaxial growth layer, potentially leading to yield issues in localized areas. The temperature and uniformity of the heating at the bottom of the graphite disk in epitaxial growth equipment are monitored parameters, and monitoring only a single area hinders accurate assessment of film growth quality. Consequently, the current problem is that precise temperature and reflectivity measurements cannot be performed across multiple regions of the wafer surface, particularly for the large number of wafers on a planetary turntable. This makes it impossible to effectively determine whether anomalies have occurred during the epitaxial growth process. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to propose a multi-region in-situ online detection method and device thereof, so as to solve the technical problem of inaccurate epitaxial layer growth detection in epitaxial growth equipment.

[0006] To achieve the above objectives, the present invention provides a multi-region in-situ online detection method for detecting the epitaxial layer growth process of a semiconductor epitaxial growth process, comprising: Before the epitaxial process, multiple probes are arranged relative to the tray in the epitaxial growth equipment; During the epitaxial growth process, a plurality of the probes are used to obtain reflection signals and infrared radiation signals from the surface of the wafer on the tray; Processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve that change in real time; After the epitaxial growth process is completed, the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment is determined according to the reflectivity curve and the temperature curve.

[0007] In some embodiments, the step of using a plurality of probes to obtain reflection signals and infrared radiation signals from the surface of the wafer on the tray includes: Get the graphite disk rotation speed; According to the rotation speed of the graphite disk, the switching frequency of the light source is set; When the light source is turned on, the reflection signal is acquired by using a plurality of the probes; When the light source is turned off, the plurality of probes are used to acquire the infrared radiation signal.

[0008] When the rotation speed of the graphite disk is greater than the set value, the light source is controlled to perform alternating switching at a frequency of 1 time per revolution; when the rotation speed of the graphite disk is less than or equal to the set value, the light source is controlled to perform alternating switching at a frequency of 3-1000 times per revolution; The range of the set value is 40-80 rpm.

[0009] In some embodiments, the real-time processing of the reflection signal and the infrared radiation signal to obtain a reflectivity curve and a temperature curve that change in real time includes: The reflectivity curve represents the change in reflectivity of the wafer epitaxial layer. The reflectivity is calculated as follows: R=(U R -U T )*sf R ; sf R = standard reflectivity / (U b -U T ); Where R represents reflectivity; U R Indicates the reflected signal voltage value when the light source is turned on; sf R Represents the calibration factor of the reflected signal; the standard reflectivity is a constant; U b Indicates the voltage value reflected by the wafer when the light source is turned on; U T Indicates the voltage value reflected by the wafer when the light source is turned off.

[0010] In some embodiments, the real-time processing of the reflection signal and the infrared radiation signal to obtain a reflectivity curve and a temperature curve that change in real time includes: The temperature curve represents the change of the wafer surface temperature value, and the temperature value is calculated as follows: T=h*c / λ*k B / In(sf T *k B *ε / U T +1)-273.15; sf T =(U T -U Toffset ) / σ*(hc / λk B / e Tset+273.15 -1); Among them, T represents the temperature value, h represents the Planck constant, c represents the speed of light, I represents the radiation intensity, n represents the reflectivity, and U T represents the voltage value reflected by the wafer when the light source is turned off, λ represents the wavelength, and ε represents the vacuum dielectric constant; U Toffset The background noise compensation value obtained without heating is in the range of -0.001~0.006v; sf T represents the temperature correction factor, the correction factor range is 0.015~0.075; σ represents the sensing factor constant; k B is the Boltzmann constant; Tset is the preset temperature threshold.

[0011] In some embodiments, judging whether the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment is normal or abnormal based on the reflectivity curve and the temperature curve includes: When R range ≤a*R average , judging that the overall running trend of the reflectivity curve is stable; When T range ≤b*T average , judging that the overall operating trend of the temperature curve is stable; Among them, R range Indicates extremely poor reflectivity, R average represents the mean reflectivity, and a represents the proportional coefficient; T range Indicates the extreme temperature difference, T average represents the mean temperature, and b represents the proportional coefficient; If the overall operating trends of the reflectivity curve and the temperature curve are both stable, it is preliminarily determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal; After preliminarily determining that the growth state of the epitaxial layer of the wafer is normal, performing a difference calculation between the temperature value collected in the temperature curve and the temperature value set by the epitaxial growth equipment to obtain a temperature difference; If the temperature difference is within the preset temperature threshold range, it is ultimately determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal.

[0012] In some embodiments, the preset temperature threshold range is 70-100°C.

[0013] In some embodiments, the step of arranging the plurality of probes relative to a tray in the epitaxial growth apparatus includes: connecting the plurality of probes to a light source via optical fibers so that light emitted by the light source reaches the wafer surface via the probes; Wherein, the light source is a single-wavelength light source with a wavelength range of 400-1000nm.

[0014] In some embodiments, the step of arranging the plurality of probes relative to the tray in the epitaxial growth apparatus further comprises: When the tray is a common tray, a plurality of the common trays are fixed on the graphite disk, and the common trays are arranged in an annular manner and are equidistant from the center of the graphite disk; When the tray is a planetary turntable, the planetary turntable rotates on the graphite disk. Several planetary turntables are arranged in an annular pattern and are equidistant from the center of the graphite disk. Each planetary turntable has multiple wafer-carrying areas.

[0015] In some embodiments, a straight line is formed by connecting the center of a wafer on a conventional tray with the center of a graphite disk and extending the straight line away from the outside of the graphite disk. Points on both sides of the wafer center and the center point are selected on the straight line for multi-area detection. At least one probe is correspondingly provided above the wafer center and the points on both sides of the wafer center. When the tray is a planetary turntable, at least one probe is provided above the center of each of the plurality of wafer-carrying areas on the planetary turntable.

[0016] In a second aspect, the present invention provides a multi-region in-situ online detection device for implementing a multi-region in-situ online detection method, comprising: A signal collection module, comprising a plurality of probes, the plurality of probes being arranged relative to a tray in the epitaxial growth device and being used to collect reflection signals and infrared radiation signals from the surface of the wafer on the tray; an acquisition module, electrically connected to the probe, and configured to acquire the reflection signal and the infrared radiation signal; a processing module, electrically connected to the acquisition module, for processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve; A judgment module is configured to judge the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment according to the reflectivity curve and the temperature curve.

[0017] The multi-region in-situ online detection method and apparatus provided by the present invention have the following beneficial effects: at the method level, by acquiring reflection signals and temperature signals from multiple regions of a wafer on a tray and distinguishing signals from multiple wafers on a satellite disk, the epitaxial layer growth status of the entire wafer can be detected. A specific implementation scheme involves using multiple probes during the epitaxial growth process to acquire reflection signals and infrared radiation signals from the wafer surface on the tray; processing these reflection and infrared radiation signals in real time to generate a real-time reflectivity curve and temperature curve; and after the epitaxial growth process is completed, determining the growth status of the epitaxial layer on the wafer in the epitaxial growth equipment based on the reflectivity and temperature curves. At the apparatus level, multiple probes are positioned above the wafer center and points on both sides of the wafer center, or at the centers of multiple wafers on a planetary turntable, to achieve positional detection of different regions. A specific implementation scheme involves installing multiple probes above the tray and electrically connecting the probes to an acquisition module. The probes acquire reflection signals and temperature signals from the wafers on the tray and receive them through the acquisition module. The acquisition module then transmits the received reflection and temperature signals to a processing module, which processes them to generate reflectivity and temperature curves. The judgment module uses the reflectivity curve and temperature curve to determine whether the epitaxial layer growth state in the epitaxial growth equipment is normal or abnormal. In summary, the method and device of the present invention obtain reflection signals and temperature signals from multiple regions of the wafer surface through the multi-probe configuration and obtain reflectivity curves and temperature curves. This improves the accuracy of the overall detection of the epitaxial layer of the wafer in the epitaxial growth equipment, effectively reduces the yield problem of single-region detection, and improves the reliability of the epitaxial growth process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A flow chart of a multi-region in-situ online detection method according to an embodiment of the present invention; Figure 2 This is a front view of the graphite disk and the probe provided in the embodiment of the present invention when used in conjunction with each other; Figure 3 A flow chart of obtaining temperature and reflectivity according to an embodiment of the present invention; Figure 4 This is a top view of the embodiment provided by the present invention when a conventional turntable is placed above the graphite disk; Figure 5 A top view of an embodiment of the present invention when a planetary turntable is located above the graphite disk; Figure 6A top view of another embodiment of the present invention when a planetary turntable is located above the graphite disk; Figure 7 A schematic diagram of an online detection device for epitaxial growth equipment according to an embodiment of the present invention; Figure 8 A schematic diagram of a reflectivity curve and a temperature value curve obtained when a GaAs process is performed in an epitaxial growth device according to an embodiment of the present invention; Reference numerals: Probe 1 , graphite disk 2 , graphite disk center 21 , tray 3 , and carrying area 31 . DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The words "including" and similar words used in this article mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Unless otherwise specified, the "connection" described in this article can be a direct connection or an indirect connection, that is, a connection through an intermediate.

[0020] In view of the problems existing in the prior art, the present invention provides a multi-region in-situ online detection method for detecting the epitaxial layer growth process and judging the growth state of the semiconductor epitaxial growth process. Figure 1 As shown, the multi-region in-situ online detection method includes the following steps: S101: Before the epitaxial growth process, multiple probes are arranged relative to the tray in the epitaxial growth equipment; In this embodiment, combined with Figure 1 and Figure 2 As shown, in this step, before detection, the three probes 1 need to be placed above the glass window of the epitaxial growth equipment.

[0021] It should be noted that the epitaxial growth apparatus includes a graphite disk 2, and the tray 3 is disposed above the graphite disk 2. The tray 3 is used to support wafers, and the graphite disk 2 rotates to uniformly heat the wafers. The probe 1 is positioned differently for different types of trays 3.

[0022] Specifically, if Figure 4As shown, when the tray is a common tray 3 , several common trays are fixed on the graphite disk 2 , and the common trays are arranged in an annular manner and are equidistant from the center 21 of the graphite disk.

[0023] At this time, the center of the wafer on one of the conventional trays is connected to the center of the graphite disk 21 and extended toward the outside of the graphite disk to form a straight line. Points on both sides of the center of the wafer and the center point are selected on the straight line for multi-area detection. At least one probe 1 is correspondingly set above the center of the wafer and the points on both sides of the center of the wafer to obtain the reflectivity and temperature of different areas of the wafer surface and detect the overall performance of the wafer surface.

[0024] like Figure 5 As shown, when the graphite disk 2 is a planetary turntable, the planetary turntable can rotate on the graphite disk 2, and several planetary turntables are arranged in a ring-shaped manner and are equidistant from the center 21 of the graphite disk. Each planetary turntable has multiple bearing areas 31.

[0025] At this time, the probes 1 are arranged in such a manner that three probes 1 are respectively arranged corresponding to the center of each of the bearing areas 31 on the planetary turntable.

[0026] In some embodiments, the number of the probes 1 may be 4 or 5, and the probes 1 may be arranged according to actual needs.

[0027] For example, reference Figure 6 As shown, five bearing areas 31 are provided on each of the planetary turntables, and one probe 1 can be provided above the center of each bearing area 31 .

[0028] S102: During the epitaxial growth process, a plurality of probes are used to obtain reflection signals and infrared radiation signals from the surface of the wafer on the tray; In this step, after the wafers are placed on the tray 3, the epitaxial growth process begins. The graphite plate 2 begins to rotate, driving the wafers on the tray 3. A light source is connected to the probe via an optical fiber. The probe illuminates the wafer through the glass window of the epitaxial growth equipment, generating reflection signals and infrared radiation signals on the wafer surface. The light source is a single-wavelength light source with a wavelength range of 400-1000 nm.

[0029] During the epitaxial growth process, the graphite disk is rotated by the motor, so each probe can obtain the reflection signal and the temperature signal on the wafer surface. Figure 3As shown, the rotation speed of the graphite disk is obtained in advance, and then the frequency of turning on or off the light source is controlled according to the rotation speed of the graphite disk, so that the probe can effectively obtain the reflection signal and the temperature signal.

[0030] It should be noted that the reflection signal from the wafer surface is collected by the probe when the light source is on, while the temperature signal from the wafer surface is collected by the probe when the light source is off. Furthermore, the light source is turned on or off according to a rule that, when the rotation speed of the graphite disk is greater than a set value, the light source is controlled to perform an alternating on-off frequency of 1 time per revolution, i.e., the light source is alternately turned on and off once for each revolution of the graphite disk. For example, when the graphite disk rotates for the first revolution, the light source is turned on, when it rotates for the second revolution, the light source is turned off, when it rotates for the third revolution, the light source is turned on, and when it rotates for the fourth revolution, the light source is turned off.

[0031] When the rotation speed of the graphite disk is less than or equal to the set value, the light source performs alternating switching at a frequency of 3-1000 times per revolution, that is, the light source is turned on and off 3-1000 times per revolution of the graphite disk.

[0032] The setting value may be in the range of 40-80 rpm.

[0033] In this embodiment, the set value is set to 60 rpm, and the control program is set so that when the rotation speed of the graphite disk is equal to 60 rpm, the light source is controlled to be turned on and off 100 times every time the graphite disk rotates one circle.

[0034] The rotational speed of the graphite disk depends on the epitaxial growth process used for different growth materials, and different processes require different rotational speeds. For example, when using GaAs epitaxial growth equipment, the rotational speed of the graphite disk is 7 rpm; when using GaO epitaxial growth equipment, the rotational speed of the graphite disk is 60 rpm; and when using SiC epitaxial growth equipment, the rotational speed of the graphite disk is 500-1000 rpm.

[0035] S103: Processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve that change in real time; It should be noted that the reflectivity curve represents the change in the reflectivity of the wafer epitaxial layer, and the temperature curve represents the change in the surface temperature of the wafer.

[0036] The specific steps of processing the reflected signal are as follows: The calculation formula of the reflectivity is: R=(U R -U T )*sfR ; sf R = standard reflectivity / (U b -U T ); Where R represents reflectivity; U R Indicates the reflected signal voltage value when the light source is turned on; sf R Represents the calibration factor of the reflected signal; the standard reflectivity is a constant; U b Indicates the voltage value reflected by the wafer when the light source is turned on; U T Indicates the voltage value reflected by the wafer when the light source is turned off.

[0037] The steps for processing the temperature signal are as follows: The light source is turned off, and an infrared radiation signal from the surface of the wafer is acquired.

[0038] A temperature value is calculated according to the infrared radiation signal.

[0039] The temperature value is calculated as follows: T=h*c / λ*k B / In(sf T *k B *ε / U T +1)-273.15; sf T =(U T -U Toffset ) / σ*(hc / λk B / e Tset+273.15 -1); Where T is the temperature, h is the Planck constant, c is the speed of light, I is the radiation intensity, n is the reflectivity, λ is the wavelength, and ε is the vacuum dielectric constant; U Toffset The background noise compensation value obtained without heating is in the range of -0.001~0.006v; sf T represents the temperature correction factor, the correction factor range is 0.015~0.075; σ represents the sensing factor constant; k B is the Boltzmann constant; Tset is the preset temperature threshold.

[0040] S104: After the epitaxial process is completed, the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment is determined according to the reflectivity curve and the temperature curve.

[0041] In this step, the specific judgment method is as follows: When R range ≤a*R average , judging that the overall running trend of the reflectivity curve is stable; When T range ≤b*T average , judging that the overall operating trend of the temperature curve is stable; Among them, R range Indicates extremely poor reflectivity, R average represents the mean reflectivity, and a represents the proportional coefficient; T range Indicates the extreme temperature difference, T average represents the mean temperature, and b represents the proportional coefficient; If the overall operating trends of the reflectivity curve and the temperature curve are both stable, it is preliminarily determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal; After preliminarily determining that the growth state of the epitaxial layer of the wafer is normal, performing a difference calculation between the temperature value collected in the temperature curve and the temperature value set by the epitaxial growth equipment to obtain a temperature difference; If the temperature difference is within the preset temperature threshold range, it is ultimately determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal.

[0042] The preset temperature threshold range is 70-100°C.

[0043] In one embodiment provided by the present invention, reference Figure 7 As shown, an online detection device for an epitaxial growth device is provided, comprising: a signal collection module, the signal collection module having a plurality of probes, the probes being used to be arranged relative to the tray in the epitaxial growth device. An acquisition module, electrically connected to the probes, and used to acquire the reflection signal and temperature signal of the wafer on the tray through the probes. A processing module, electrically connected to the acquisition module, for receiving the reflection signal and the temperature signal and processing the reflection signal and the temperature signal to obtain a reflectivity curve and a temperature curve. A judgment module, electrically connected to the processing module, judges the growth state of the epitaxial layer of the wafer in the epitaxial growth device according to the reflectivity curve and the temperature curve. Wherein, the light source is arranged inside the in-situ online detection device, and is connected to the probe via an optical fiber.

[0044] In this embodiment, the light source may be an LED lamp. Three probes are installed above the tray and are electrically connected to the acquisition module. The probes collect reflection signals and temperature signals from the wafers on the graphite tray and receive them via the acquisition module. The acquisition module transmits the received reflection and temperature signals to the processing module, which processes them to generate a reflectivity curve and a temperature curve. Finally, the judgment module uses the reflectivity and temperature curves to determine the growth status of the epitaxial layer on the wafers in the epitaxial growth apparatus.

[0045] In one embodiment provided by the present invention, reference Figure 8 As shown, when growing p-type GaAs material, the EPI process recipe is carried out in the epitaxial growth equipment, and the tray type is a planetary turntable, such as Figure 6 As shown, the probe is set at the center of each wafer. The rotation speed of the graphite disk is 7 rpm, and the set temperature is 530°C. By adopting the online detection method and device of the epitaxial growth equipment provided in the above embodiment, a reflectivity curve and a temperature value curve are obtained. Among them, the corresponding reflectivity and temperature data on the graphite disk have been filtered by the algorithm and are not displayed in the curve. It is judged that the overall operating trends of the corresponding reflectivity curves and temperature curves in the three areas are stable and within the set threshold range. Therefore, the growth state of the epitaxial layer GaAs material is judged to be normal.

[0046] In summary, the method and device of the present invention obtain the reflection signals and temperature signals of multiple areas on the wafer surface through the setting of multiple probes and obtain the reflectivity curve and temperature curve, which improves the accuracy of the overall detection of the epitaxial layer of the wafer in the epitaxial growth equipment, effectively reduces the yield problem of single area detection, and improves the reliability of the epitaxial growth process.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A multi-region in-situ online detection method for detecting the epitaxial layer growth process and judging the growth state of a semiconductor epitaxial growth process, characterized in that: include: Before the epitaxial growth process, multiple probes are arranged relative to the tray in the epitaxial growth equipment; During the epitaxial growth process, a plurality of the probes are used to obtain reflection signals and infrared radiation signals from the surface of the wafer on the tray; Processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve that change in real time; After the epitaxial growth process is completed, the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment is determined according to the reflectivity curve and the temperature curve.

2. The multi-region in-situ online detection method according to claim 1, characterized in that: The method of using the plurality of probes to obtain the reflection signal and infrared radiation signal from the surface of the wafer on the tray includes: Get the graphite disk rotation speed; According to the rotation speed of the graphite disk, the switching frequency of the light source is set; When the light source is turned on, the reflection signal is acquired by using a plurality of the probes; When the light source is turned off, the infrared radiation signal is obtained by using multiple probes; When the rotation speed of the graphite disk is greater than the set value, the light source is controlled to perform alternating switching at a frequency of 1 time per revolution; when the rotation speed of the graphite disk is less than or equal to the set value, the light source is controlled to perform alternating switching at a frequency of 3-1000 times per revolution; The range of the set value is 40-80 rpm.

3. The multi-region in-situ online detection method according to claim 2, characterized in that: The process of processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve that change in real time includes: The reflectivity curve represents the change in reflectivity of the wafer epitaxial layer. The reflectivity is calculated as follows: R=(U R -U T )*sf R ; sf R = standard reflectivity / (U b -U T ); Where R represents reflectivity; U R Indicates the reflected signal voltage value when the light source is turned on; sf R Represents the calibration factor of the reflected signal; the standard reflectivity is a constant; U b Indicates the voltage value reflected by the wafer when the light source is turned on; U T Indicates the voltage value reflected by the wafer when the light source is turned off.

4. The multi-region in-situ online detection method according to claim 2, characterized in that: The process of processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve that change in real time includes: The temperature curve represents the change of the wafer surface temperature value, and the temperature value is calculated as follows: T=h*c / λ*k B / In(sf T *k B *ε / U T +1)-273.15; sf T =(U T -U Toffset ) / σ*(hc / λk B / e Tset+273.15 -1); Where T is the temperature, h is the Planck constant, c is the speed of light, I is the radiation intensity, n is the reflectivity, λ is the wavelength, ε is the vacuum dielectric constant, and U is the T Indicates the voltage value reflected by the wafer when the light source is turned off; U Toffset The background noise compensation value obtained without heating is in the range of -0.001~0.006v; sf T represents the temperature correction factor, the correction factor range is 0.015~0.075; σ represents the sensing factor constant; k B is the Boltzmann constant; Tset is the preset temperature threshold.

5. The multi-region in-situ online detection method according to claim 1, characterized in that: The step of judging the growth state of the epitaxial layer of the wafer in the epitaxial growth device according to the reflectivity curve and the temperature curve includes: When R range ≤a*R average , judging that the overall running trend of the reflectivity curve is stable; When T range ≤b*T average , judging that the overall operating trend of the temperature curve is stable; Among them, R range Indicates extremely poor reflectivity, R average represents the mean reflectivity, and a represents the proportional coefficient; T range Indicates the extreme temperature difference, T average represents the mean temperature, and b represents the proportional coefficient; If the overall operating trends of the reflectivity curve and the temperature curve are both stable, it is preliminarily determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal; After preliminarily determining that the growth state of the epitaxial layer of the wafer is normal, performing a difference calculation between the temperature value collected in the temperature curve and the temperature value set by the epitaxial growth equipment to obtain a temperature difference; If the temperature difference is within the preset temperature threshold range, it is ultimately determined that the growth state of the wafer epitaxial layer is normal, otherwise it is abnormal.

6. The multi-region in-situ online detection method according to claim 5, characterized in that: The preset temperature threshold range is 70-100°C.

7. The multi-region in-situ online detection method according to claim 1, characterized in that: The method of arranging the plurality of probes relative to the tray in the epitaxial growth device includes: connecting the plurality of probes to a light source via optical fibers so that light emitted by the light source reaches the wafer surface via the probes; Wherein, the light source is a single-wavelength light source with a wavelength range of 400-1000nm.

8. The multi-region in-situ online detection method according to claim 1, characterized in that: The method of arranging the plurality of probes relative to the tray in the epitaxial growth device further comprises: When the tray is a common tray, a plurality of the common trays are fixed on the graphite disk, and the common trays are arranged in an annular manner and are equidistant from the center of the graphite disk; When the tray is a planetary turntable, the planetary turntable rotates on the graphite disk. Several planetary turntables are arranged in an annular pattern and are equidistant from the center of the graphite disk. Each planetary turntable has multiple wafer-carrying areas.

9. The multi-region in-situ online detection method according to claim 8, characterized in that: When the tray is a conventional tray, a straight line is formed by connecting the center of a wafer on the conventional tray with the center of the graphite disk and extending the straight line away from the outside of the graphite disk. Points on both sides of the wafer center and the center point are selected on the straight line for multi-area detection. At least one probe is correspondingly provided above the wafer center and the points on both sides of the wafer center. When the tray is a planetary turntable, at least one probe is provided above the center of each of the plurality of wafer-carrying areas on the planetary turntable.

10. A multi-region in-situ online detection device for implementing a multi-region in-situ online detection method, characterized in that: include: A signal collection module, comprising a plurality of probes, the plurality of probes being arranged relative to a tray in the epitaxial growth device and being used to collect reflection signals and infrared radiation signals from the surface of the wafer on the tray; an acquisition module, electrically connected to the probe, and configured to acquire the reflection signal and the infrared radiation signal; a processing module, electrically connected to the acquisition module, for processing the reflection signal and the infrared radiation signal in real time to obtain a reflectivity curve and a temperature curve; A judgment module is configured to judge the growth state of the epitaxial layer of the wafer in the epitaxial growth equipment according to the reflectivity curve and the temperature curve.

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