Multi-zone in-situ online detection method and device thereof

Abstract

The application provides a multi-region in-situ online detection method and device thereof, the multi-region in-situ online detection method comprises the following steps: before an epitaxial process, a plurality of probes are arranged opposite to a tray in an epitaxial growth device; during the epitaxial process, the plurality of probes are used to acquire reflection signals and infrared radiation signals of wafer surfaces on the tray; the reflection signals and the infrared radiation signals are processed in real time to obtain real-time changing reflectivity curves and temperature curves; after the epitaxial process is completed, the wafer epitaxial layer growth state in the epitaxial growth device is judged according to the reflectivity curves and the temperature curves. The application acquires the reflection signals and the temperature signals of the wafer surfaces in multiple regions by using the arrangement of the plurality of probes and obtains the reflectivity curves and the temperature curves, improves the accuracy of the overall detection of the wafer epitaxial layer in the epitaxial growth device, effectively reduces the yield problem of single region detection, and improves the reliability of the epitaxial growth process.

Description

Technical Field

[0001] This invention relates to the field of semiconductor epitaxial growth equipment technology, and in particular to a multi-region in-situ online detection method and apparatus. Background Technology

[0002] Epitaxial growth is a technique for growing new single-crystal layers along the crystal orientation of a single-crystal substrate. Its core principle is to achieve homo- or hetero-epitaxial growth by matching the lattice constants of the materials. In semiconductor device manufacturing, the electrical characteristics of transistors are enhanced by epitaxially growing different film materials, thereby achieving higher device drive current, higher switching frequency, and superior chip performance.

[0003] In epitaxial growth equipment, wafer substrates cannot be directly placed on metal for epitaxial deposition. This involves multiple influencing factors such as gas flow direction (horizontal, vertical), temperature, pressure, fixation, and contaminant shedding. Therefore, a graphite disk base is required, and the substrate is placed on a tray above the graphite disk before epitaxial growth deposition of the thin film is performed. The graphite disk is primarily heated by high-frequency induction heating, infrared radiation heating, and resistance heating. However, the heating temperature of the graphite disk requires strict temperature control and monitoring of heating uniformity. Therefore, real-time monitoring of temperature and reflectivity parameters in multiple areas of the wafer surface is necessary to confirm whether the growth process is abnormal. Current technology typically uses a temperature sensor to scan the graphite disk through a glass window. The graphite disk rotates at a certain speed, and the temperature sensor probe moves gradually from the center to the edge of the disk to detect the temperature distribution across the entire disk.

[0004] In existing in-situ inspection devices, the epitaxial layer growth process cannot be inspected across multiple regions; instead, only a single probe is used for single-region inspection. The inspection results cannot accurately reflect the overall condition of the epitaxial growth layer, potentially leading to yield issues in localized areas. The heating temperature and uniformity at the bottom of the graphite disk in the epitaxial growth equipment are monitoring parameters; inspecting only a single area affects the accurate assessment of film growth quality. Therefore, current methods cannot accurately detect the temperature and reflectivity of different areas on the wafer surface or the large number of wafers on a planetary turntable, making it impossible to effectively determine whether any abnormalities have occurred during the epitaxial growth process. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a multi-region in-situ online detection method and apparatus to solve the technical problem of inaccurate detection of epitaxial layer growth 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 in semiconductor epitaxial growth processes, comprising:

[0007] Before the epitaxial process, multiple probes are positioned relative to the tray inside the epitaxial growth equipment;

[0008] During the epitaxial process, multiple probes are used to acquire the reflected signals and infrared radiation signals from the wafer surface on the tray;

[0009] The reflected signal and infrared radiation signal are processed in real time to obtain the real-time changing reflectivity curve and temperature curve;

[0010] After the epitaxial process is completed, the growth state of the wafer epitaxial layer in the epitaxial growth equipment is determined based on the reflectivity curve and temperature curve.

[0011] In some embodiments, acquiring the reflected signal and infrared radiation signal from the wafer surface on the tray using multiple probes includes:

[0012] Obtain the rotational speed of the graphite disk;

[0013] The switching frequency of the light source is set according to the rotational speed of the graphite disk;

[0014] With the light source on, multiple probes are used to acquire the reflected signal;

[0015] With the light source off, multiple probes are used to acquire the infrared radiation signal.

[0016] Specifically, when the rotation speed of the graphite disk is greater than the set value, the light source is controlled to perform alternating switching frequency of 1 time / revolution; when the rotation speed of the graphite disk is less than or equal to the set value, the light source performs alternating switching frequency of 3-1000 times / revolution.

[0017] The set value ranges from 40 to 80 revolutions per minute.

[0018] In some embodiments, the step of processing the reflected signal and infrared radiation signal in real time to obtain the real-time changing reflectivity curve and temperature curve includes:

[0019] The reflectivity curve represents the change in reflectivity of the epitaxial layer of the wafer, and the formula for calculating the reflectivity is:

[0020] R = (U R -U T )*sf R ;

[0021] sf R =Standard reflectance / (U b -U T );

[0022] Where R represents reflectivity; U RThis represents the reflected signal voltage value when the light source is turned on; sf R The calibration factor represents the reflected signal; the standard reflectivity is a constant; U b This represents the voltage value reflected by the wafer when the light source is turned on; U T This represents the voltage value reflected by the wafer when the light source is turned off.

[0023] In some embodiments, the step of processing the reflected signal and infrared radiation signal in real time to obtain the real-time changing reflectivity curve and temperature curve includes:

[0024] The temperature curve represents the change in the temperature value on the wafer surface, and the formula for calculating the temperature value is:

[0025] T=h*c / λ*k B / In(sf T *k B *ε / U T +1)-273.15;

[0026] sf T =(U T -U Toffset ) / σ*(hc / λk B / e Tset+273.15 -1);

[0027] Where T represents temperature, h represents Planck's constant, c represents the speed of light, I represents radiation intensity, n represents reflectivity, and U... T U represents the voltage reflected by the wafer when the light source is turned off, λ represents the wavelength, and ε represents the vacuum dielectric constant; Toffset Background noise compensation values ​​obtained without heating, wherein the compensation values ​​range from -0.001 to 0.006V; sf T σ represents the temperature correction factor, which ranges from 0.015 to 0.075; k represents the sensing factor constant. B is the Boltzmann constant; Tset is the preset temperature threshold.

[0028] In some embodiments, determining whether the growth state of the wafer epitaxial layer in the epitaxial growth equipment is normal or abnormal based on the reflectivity curve and temperature curve includes:

[0029] When R range ≤a*R average The overall trend of the reflectivity curve is judged to be stable.

[0030] When T range ≤b*T average The temperature curve is judged to have a stable overall operating trend.

[0031] Among them, R range Indicates extremely poor reflectivity, R average This represents the mean reflectance, and 'a' represents the proportionality coefficient.

[0032] T range Indicates the temperature range, T average This represents the average temperature, and b represents the proportionality coefficient.

[0033] If the overall trend of the reflectivity curve and the temperature curve is stable, it is preliminarily judged that the growth state of the wafer epitaxial layer is normal; otherwise, it is abnormal.

[0034] Once it is preliminarily determined that the growth state of the wafer epitaxial layer is normal, the temperature value collected in the temperature curve is compared with the temperature value set by the epitaxial growth equipment to obtain the temperature difference.

[0035] If the temperature difference is within the preset temperature threshold range, the wafer epitaxial layer growth state is determined to be normal; otherwise, it is abnormal.

[0036] In some embodiments, the preset temperature threshold ranges from 70 to 100°C.

[0037] In some embodiments, the arrangement of the plurality of probes relative to a tray within the epitaxial growth apparatus includes:

[0038] Multiple probes are connected to a light source via optical fibers, so that the light emitted by the light source reaches the wafer surface via the probes;

[0039] The light source is a single-wavelength light source with a wavelength range of 400-1000nm.

[0040] In some embodiments, the arrangement of the plurality of probes relative to a tray within the epitaxial growth apparatus further includes:

[0041] When the tray is a standard type tray, several standard type trays are fixed on the graphite disk. The standard type trays are arranged in a ring at intervals and are all equidistant from the center of the graphite disk.

[0042] When the tray is a planetary turntable, the planetary turntable rotates on the graphite disk. Several planetary turntables are arranged in a ring at intervals and are all equidistant from the center of the graphite disk. Each planetary turntable has multiple wafer-carrying areas.

[0043] In some embodiments, a line is drawn connecting the center of the wafer on a conventional tray to the center of the graphite disk and extending outward away from the graphite disk to form a straight line. Points on both sides of the wafer center and the center point are selected on the straight line for multi-region detection. At least one probe is provided above the wafer center and the points on both sides of the wafer center.

[0044] When the tray is a planetary turntable, at least one probe is provided above the center of each of the multiple wafer-bearing areas on the planetary turntable.

[0045] Secondly, the present invention provides a multi-region in-situ online detection device for implementing a multi-region in-situ online detection method, comprising:

[0046] The signal collection module includes multiple probes, which are arranged opposite to a tray in the epitaxial growth equipment to collect reflected signals and infrared radiation signals from the wafer surface on the tray.

[0047] An acquisition module, electrically connected to the probe, is used to acquire the reflected signal and the infrared radiation signal;

[0048] The processing module, electrically connected to the acquisition module, processes the reflected signal and infrared radiation signal in real time to obtain the reflectivity curve and temperature curve.

[0049] The judgment module determines the growth state of the wafer epitaxial layer in the epitaxial growth equipment based on the reflectivity curve and temperature curve.

[0050] The beneficial effects of the multi-region in-situ online detection method and apparatus provided by this invention are as follows: At the method level, by acquiring and distinguishing the reflection and temperature signals of multiple regions of the wafer on the tray and the signals of multiple wafers on the satellite disk, the overall epitaxial layer growth status of the wafer can be detected. Specifically, multiple probes during the epitaxial process acquire the reflection and infrared radiation signals from the wafer surface on the tray; the reflection and infrared radiation signals are processed in real time to obtain real-time changing reflectivity and temperature curves; after the epitaxial process is completed, the growth status of the wafer epitaxial layer in the epitaxial growth equipment is determined 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 positioning detection of different regions. Specifically, multiple probes are installed above the tray, electrically connected to the acquisition module, and the probes acquire the reflection and temperature signals of the wafer on the tray, which are then received by the acquisition module. The acquisition module then sends the received reflection and temperature signals to the processing module, which processes the reflection and temperature signals to obtain the reflectivity and temperature curves. The judgment module determines whether the epitaxial layer growth state in the epitaxial growth equipment is normal or abnormal by using reflectivity and temperature curves. In summary, the method and apparatus of this invention, through the use of multiple probes to acquire reflection and temperature signals from multiple regions on the wafer surface and obtain reflectivity and temperature curves, improves the accuracy of overall detection of the wafer epitaxial layer in the epitaxial growth equipment, effectively reduces the yield problem of single-region detection, and enhances the reliability of the epitaxial growth process. Attached Figure Description

[0051] Figure 1 A flowchart of a multi-region in-situ online detection method provided by the present invention;

[0052] Figure 2 This is a front view of the graphite disk and probe used in conjunction with an embodiment of the present invention.

[0053] Figure 3 A flowchart illustrating the temperature and reflectivity obtained from embodiments of the present invention;

[0054] Figure 4 This is a top view of an embodiment of the present invention when a conventional turntable is located above the graphite disk;

[0055] Figure 5 This is a top view of an embodiment of the present invention when a planetary turntable is located above the graphite disk;

[0056] Figure 6 This is a top view of another embodiment of the present invention when a planetary turntable is located above the graphite disk;

[0057] Figure 7 A schematic diagram of the online detection device for the epitaxial growth equipment provided in this embodiment of the invention;

[0058] Figure 8 A schematic diagram of the reflectance curve and temperature curve obtained during the GaAs process in the epitaxial growth equipment provided by the present invention;

[0059] Figure label:

[0060] Probe 1, graphite disk 2, center of graphite disk 21, tray 3, bearing area 31. Detailed Implementation

[0061] To make the objectives, 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 with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. Unless otherwise specified, the term "connection" used herein can refer to a direct connection or an indirect connection, i.e., a connection through an intermediate object.

[0062] To address the problems existing in the prior art, this invention provides a multi-region in-situ online detection method for detecting the epitaxial layer growth process and determining the growth state in semiconductor epitaxial growth processes. (Refer to...) Figure 1 As shown, the multi-region in-situ online detection method includes the following steps:

[0063] S101: Before the epitaxial growth process, multiple probes are positioned relative to the tray inside the epitaxial growth equipment;

[0064] 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.

[0065] It should be noted that the epitaxial growth equipment includes a graphite disk 2, and a tray 3 is positioned above the graphite disk 2. The tray 3 is used to support the wafer, and the graphite disk 2 rotates to uniformly heat the wafer. The position of the probe 1 varies depending on the type of tray 3.

[0066] Specifically, such as Figure 4As shown, when the tray is a standard tray 3, several standard trays are fixed on the graphite disk 2. The standard trays are arranged in a ring at intervals and are all equidistant from the center 21 of the graphite disk.

[0067] At this time, a line is drawn connecting the center of the wafer on a standard tray to the center of the graphite disk 21 and extending outward away from the graphite disk to form a straight line. Points on both sides of the wafer center and the center point are selected on the straight line for multi-region detection. At least one probe 1 is set above the wafer center and the points on both sides of the wafer center to obtain the reflectivity and temperature of different areas of the wafer surface and detect the overall performance of the wafer surface.

[0068] 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 at intervals, and are all equidistant from the center 21 of the graphite disk. Each planetary turntable has multiple bearing areas 31.

[0069] At this time, the probe 1 is set up such that the three probes 1 are respectively positioned at the center of each of the bearing areas 31 on the planetary turntable.

[0070] In some embodiments, the number of probes 1 can be 4 or 5, and the arrangement of probes 1 can be made according to actual needs.

[0071] For example, refer to Figure 6 As shown, each planetary turntable is provided with 5 bearing areas 31, and a probe 1 can be provided above the center of each bearing area 31.

[0072] S102: During the epitaxial process, multiple probes are used to acquire the reflected signals and infrared radiation signals from the wafer surface on the tray;

[0073] In this step, after the wafer is placed on the tray 3, the epitaxial growth process begins. At this time, the graphite disk 2 starts to rotate, causing the wafer on the tray 3 to rotate as well. The light source is connected to the probe via an optical fiber, and shines light onto the wafer through the glass window of the epitaxial growth equipment, causing the wafer surface to generate reflected signals and infrared radiation signals. The light source is a single-wavelength light source with a wavelength range of 400-1000 nm.

[0074] During the epitaxial growth process, the graphite disk rotates under the drive of a motor, so each probe can acquire the reflected signal and the temperature signal from the wafer surface. Specifically, combined with Figure 3As shown, the rotational speed of the graphite disk is obtained in advance, and then the frequency of turning the light source on or off is controlled according to the rotational speed of the graphite disk, so that the probe can effectively acquire the reflected signal and the temperature signal.

[0075] It should be noted that the reflected signal from the wafer surface is acquired by the probe when the light source is on, while the temperature signal from the wafer surface is acquired by the probe when the light source is off. Furthermore, the light source is switched on and off according to the following rule: when the rotation speed of the graphite disk exceeds a set value, the light source is controlled to alternately switch on and off at a frequency of 1 time per revolution. That is, the light source is alternately turned on or off once per 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.

[0076] When the rotation speed of the graphite disk is less than or equal to the set value, the light source performs alternating switching frequency of 3-1000 times / revolution, that is, the light source is controlled to turn on and off 3-1000 times for every revolution of the graphite disk.

[0077] The set value can be in the range of 40-80 revolutions per minute.

[0078] In this embodiment, the set value is set to 60 revolutions per minute, and the control program is set to control the light source to turn on and off 100 times for every revolution of the graphite disk when the graphite disk rotates at 60 revolutions per minute.

[0079] Furthermore, the rotational speed of the graphite disk is related to the epitaxial growth process of different growth materials, and the rotational speed varies for different processes. 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.

[0080] S103: The reflected signal and infrared radiation signal are processed in real time to obtain the real-time changing reflectivity curve and temperature curve;

[0081] It should be noted that the reflectivity curve represents the change in reflectivity of the wafer epitaxial layer, and the temperature curve represents the change in the surface temperature of the wafer.

[0082] The specific steps for processing the reflected signal are as follows:

[0083] The formula for calculating the reflectivity is:

[0084] R = (UR -U T )*sf R ;

[0085] sf R =Standard reflectance / (U b -U T );

[0086] Where R represents reflectivity; U R This represents the reflected signal voltage value when the light source is turned on; sf R The calibration factor represents the reflected signal; the standard reflectivity is a constant; U b This represents the voltage value reflected by the wafer when the light source is turned on; U T This represents the voltage value reflected by the wafer when the light source is turned off.

[0087] The specific processing steps for the temperature signal are as follows:

[0088] The light source is turned off, and the infrared radiation signal on the wafer surface is acquired.

[0089] The temperature value is calculated based on the infrared radiation signal.

[0090] The formula for calculating the temperature value is:

[0091] T=h*c / λ*k B / In(sf T *k B *ε / U T +1)-273.15;

[0092] sf T =(U T -U Toffset ) / σ*(hc / λk B / e Tset+273.15 -1);

[0093] Where T represents temperature, h represents Planck's constant, c represents the speed of light, I represents radiation intensity, n represents reflectivity, λ represents wavelength, and ε represents the vacuum dielectric constant; U Toffset Background noise compensation values ​​obtained without heating, wherein the compensation values ​​range from -0.001 to 0.006V; sf T σ represents the temperature correction factor, which ranges from 0.015 to 0.075; k represents the sensing factor constant. B is the Boltzmann constant; Tset is the preset temperature threshold.

[0094] S104: After the epitaxial process is completed, the growth state of the wafer epitaxial layer in the epitaxial growth equipment is determined based on the reflectivity curve and temperature curve.

[0095] The specific judgment method in this step is as follows:

[0096] When R range ≤a*R average The overall trend of the reflectivity curve is judged to be stable.

[0097] When T range ≤b*T average The temperature curve is judged to have a stable overall operating trend.

[0098] Among them, R range Indicates extremely poor reflectivity, R average This represents the mean reflectance, and 'a' represents the proportionality coefficient.

[0099] T range Indicates the temperature range, T average This represents the average temperature, and b represents the proportionality coefficient.

[0100] If the overall trend of the reflectivity curve and the temperature curve is stable, it is preliminarily judged that the growth state of the wafer epitaxial layer is normal; otherwise, it is abnormal.

[0101] Once it is preliminarily determined that the growth state of the wafer epitaxial layer is normal, the temperature value collected in the temperature curve is compared with the temperature value set by the epitaxial growth equipment to obtain the temperature difference.

[0102] If the temperature difference is within the preset temperature threshold range, the wafer epitaxial layer growth state is determined to be normal; otherwise, it is abnormal.

[0103] The preset temperature threshold ranges from 70 to 100°C.

[0104] In one embodiment provided by the present invention, reference is made to... Figure 7 As shown, an online detection device for an epitaxial growth apparatus includes: a signal collection module having several probes positioned opposite a tray in the epitaxial growth apparatus; an acquisition module electrically connected to the probes, which acquires reflection and temperature signals from the wafer on the tray; a processing module electrically connected to the acquisition module, which receives and processes the reflection and temperature signals to obtain a reflectivity curve and a temperature curve; and a judgment module electrically connected to the processing module, which determines the epitaxial layer growth state of the wafer in the epitaxial growth apparatus based on the reflectivity and temperature curves. A light source is located inside the in-situ online detection device and connected to the probes via an optical fiber.

[0105] In this embodiment, the light source can be an LED lamp. Three probes are mounted above the tray, and each probe is electrically connected to the acquisition module. The probes collect reflection and temperature signals from the wafer on the graphite disk, and these signals are received by the acquisition module. The acquisition module then sends the received reflection and temperature signals to the processing module, which processes the signals to obtain reflectivity and temperature curves. Finally, the judgment module uses the reflectivity and temperature curves to determine the growth state of the epitaxial layer on the wafer in the epitaxial growth equipment.

[0106] In one embodiment provided by the present invention, reference is made to... Figure 8 As shown, when growing p-type GaAs material, the EPI process recipe is performed within the epitaxial growth equipment, and the tray type is a planetary rotary disk, as shown. Figure 6 As shown, the probes are positioned at the center of each wafer. The graphite disk rotates at 7 revolutions per minute, and the set temperature is 530°C. Using the online detection method and apparatus of the epitaxial growth equipment provided in the above embodiment, reflectivity curves and temperature curves are obtained. The reflectivity and temperature data corresponding to the graphite disk have been filtered out from the curves by an algorithm. The overall trend of the reflectivity and temperature curves in the three regions is stable and within the set threshold range. Therefore, the growth state of the epitaxial GaAs material is judged to be normal.

[0107] In summary, the method and apparatus of this invention acquire reflection and temperature signals from multiple regions on the wafer surface by setting up multiple probes, and obtain reflectivity and temperature curves, which improves the accuracy of overall detection of the wafer epitaxial layer in the epitaxial growth equipment, effectively reduces the yield problem of single-region detection, and improves the reliability of the epitaxial growth process.

[0108] The above description is merely a specific implementation of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.

Claims

1. A multi-zone in-situ on-line detection method for detecting the growth process of an epitaxial layer and determining the growth state of a semiconductor epitaxial growth process, characterized in that, The method comprises the following steps: Before epitaxial process, a plurality of probes are arranged opposite to a tray in an epitaxial growth device; During epitaxial process, the plurality of probes are used to acquire reflection signals and infrared radiation signals of wafer surfaces on the tray; The reflection signals and infrared radiation signals are processed in real time to obtain real-time changing reflectivity curves and temperature curves; After epitaxial process, the wafer epitaxial layer growth state in the epitaxial growth device is judged according to the reflectivity curves and temperature curves; The wafer epitaxial layer growth state is judged according to the reflectivity curves and temperature curves, which comprises the following steps: When R range ≤ a * R average , it is determined that the overall operation trend of the reflectivity curve is smooth. When T range ≤ b * T average , it is judged that the overall operation trend of the temperature curve is stable. wherein R range represents the reflectance range, R average represents the reflectance average, a represents the proportional coefficient; T range denotes the temperature range, T average denotes the temperature mean, b represents the proportionality coefficient; If the overall operation trend of the reflectivity curves and temperature curves is stable, it is preliminarily judged that the wafer epitaxial layer growth state is normal, otherwise, it is abnormal; After the wafer epitaxial layer growth state is preliminarily judged to be normal, the temperature difference is calculated by subtracting the temperature value collected in the temperature curve from the temperature value set in the epitaxial growth device; If the temperature difference is within a preset temperature threshold range, it is finally judged that the wafer epitaxial layer growth state is normal, otherwise, it is abnormal; The plurality of probes are arranged opposite to the tray in the epitaxial growth device, which further comprises the following steps: When the tray is a common tray, a plurality of common trays are fixed on a graphite disc, the common trays are arranged in a ring shape with equal intervals, and the centers of the common trays are equidistant from the center of the graphite disc; When the tray is a planetary turntable, the planetary turntable rotates on the graphite disc, a plurality of planetary turntables are arranged in a ring shape with equal intervals, and the centers of the planetary turntables are equidistant from the center of the graphite disc, and each planetary turntable has a plurality of wafer supporting areas; When the tray is a common tray, a straight line is formed by connecting the center of a wafer on the common tray with the center of the graphite disc and extending to the outside of the graphite disc, and the center of the wafer and the points on both sides of the wafer center on the straight line are selected for multi-region detection, and at least one probe is arranged 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 arranged above each wafer supporting area center on the planetary turntable.

2. The multi-zone in-situ on-line detection method according to claim 1, wherein, The plurality of probes are used to acquire the reflection signals and infrared radiation signals of wafer surfaces on the tray, which comprises the following steps: The rotation speed of the graphite disc is acquired; The switching frequency of a light source is set according to the rotation speed of the graphite disc; In the state that the light source is turned on, the plurality of probes are used to acquire the reflection signals; In the state that the light source is turned off, the plurality of probes are used to acquire the infrared radiation signals; When the rotation speed of the graphite disc is greater than a set value, the light source is controlled to execute an alternating switching frequency of 1 time per revolution; when the rotation speed of the graphite disc is less than or equal to the set value, the light source executes an alternating switching frequency of 3-1000 times per revolution; The set value ranges from 40 to 80 revolutions per minute.

3. The multi-zone in-situ on-line detection method according to claim 2, wherein, The reflection signals and infrared radiation signals are processed in real time to obtain real-time changing reflectivity curves and temperature curves, which comprises the following steps: The reflectivity curve represents the change of the reflectivity of the wafer epitaxial layer, and the calculation formula of the reflectivity is as follows: R = (U R - U T ) * sf R ; sf R = standard reflectance / (U b -U T ); where R represents reflectivity; U R represents the reflected signal voltage value when the light source is on; sf R represents the calibration factor of the reflected signal; the standard reflectivity is a constant; U b represents the voltage value reflected by the wafer when the light source is on; U T represents the voltage value reflected by the wafer when the light source is off.

4. The multi-zone in-situ on-line detection method according to claim 2, wherein, The real-time processing of the reflection signal and the infrared radiation signal includes: The temperature curve represents the change of the wafer surface temperature value, and the calculation formula of the temperature value is: T= ； ； where 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, λ represents the wavelength, ε represents the vacuum permittivity, U T represents the voltage value reflected by the wafer when the light source is off; U Toffset represents the background noise compensation value obtained without temperature rise, the compensation value ranges from -0.001 to 0.006v; sf T represents the temperature correction factor, the correction factor ranges from 0.015 to 0.075; σ represents the sensor factor constant; k B is the Boltzmann constant; Tset is the preset temperature threshold.

5. The multi-zone in-situ on-line detection method according to claim 1, wherein, The preset temperature threshold range is 70-100 DEG C.

6. The multi-zone in-situ on-line detection method according to claim 1, wherein, The multiple probes are arranged opposite to the tray in the epitaxial growth device, including: The multiple probes are connected with the light source through optical fibers, so that the light emitted by the light source reaches the wafer surface through the probes; The light source is a single-wavelength light source, and the wavelength range is 400-1000 nm.

7. A multi-zone in-situ on-line detection apparatus for implementing the multi-zone in-situ on-line detection method according to any one of claims 1 to 6, characterized in that, Including: A signal collection module includes multiple probes arranged opposite to the tray in the epitaxial growth device, for collecting the reflection signal and the infrared radiation signal on the wafer surface of the tray; An acquisition module is electrically connected with the probes, for acquiring the reflection signal and the infrared radiation signal; A processing module is electrically connected with the acquisition module, for real-time processing of the reflection signal and the infrared radiation signal to obtain a reflectivity curve and a temperature curve; A judgment module judges the epitaxial layer growth state of the wafer in the epitaxial growth device according to the reflectivity curve and the temperature curve.

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