A temperature calibration method

Abstract

The application provides a temperature calibration method, and relates to the technical field of semiconductor equipment, which comprises the following steps: setting n contrast process temperatures, obtaining process result indexes of a reference cavity at each contrast process temperature, and obtaining measured temperatures required by a to-be-matched cavity to reach the same process result indexes, so as to obtain n measured temperatures corresponding to the contrast process temperatures; based on Planck's black-body radiation law, the radiation rate matching ratios of each contrast process temperature and the corresponding measured temperature are calculated respectively, and a relationship model between the radiation rate matching ratio and the measured temperature is established; for any measured temperature of the to-be-matched cavity, the corresponding radiation rate matching ratio is obtained by interpolation based on the relationship model, and the calibration temperature of the to-be-matched cavity is calculated by using the radiation rate matching ratio obtained by interpolation. The application improves the consistency of process result indexes among process cavities, and reduces the influence of factors such as mechanical assembly differences, temperature field-flow field coupling effects and the like in the process cavity on the temperature measurement result.

Description

Technical Field

[0001] This invention relates to the technical field of semiconductor devices, and in particular to a temperature calibration method. Background Technology

[0002] Real-time monitoring of substrate temperature is crucial for ensuring process quality during the operation of semiconductor equipment. Temperature measurement technologies are mainly divided into two categories: contact and non-contact. Contact measurements primarily utilize sensors such as resistance temperature detectors (RTDs) and thermocouples; non-contact measurements include techniques such as fluorescence thermometry and infrared thermometry. Among these, infrared thermometry is widely used in the field of semiconductor equipment temperature monitoring due to its advantages such as non-contact operation and fast response.

[0003] In semiconductor manufacturing systems, a single semiconductor device typically contains multiple independent process chambers. This necessitates the use of multiple infrared thermometers to synchronously monitor the temperature of each chamber, enabling real-time acquisition of temperature parameters for each chamber. However, the measurement accuracy of infrared thermometers is affected by several parameters, including the emissivity of the object being measured, the measurement distance, the sensor position, and the field of view. Therefore, the infrared thermometers must undergo initial calibration before the semiconductor device is put into use.

[0004] It is worth noting that during substrate processing, due to complex factors such as differences in mechanical assembly and temperature-flow field coupling effects within each process cavity, even under the same process conditions, relying solely on an initially calibrated infrared thermometer may still lead to deviations in process result indicators between different process cavities. This results in the inconsistency of process results between different process cavities in the same type of semiconductor equipment, thereby affecting the quality stability of semiconductor products. Summary of the Invention

[0005] The purpose of this invention is to provide a temperature calibration method to solve the problem that relying solely on an initially calibrated infrared thermometer may still lead to deviations in process result indicators between different process cavities.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] A temperature calibration method for a semiconductor device, the semiconductor device including a reference cavity and a cavity to be matched, comprising the following steps:

[0008] Set n comparison process temperatures, obtain the process result index of the reference cavity at each comparison process temperature, and obtain the measured temperature required for the cavity to be matched to achieve the same process result index, thereby obtaining n measured temperatures that correspond one-to-one with each of the comparison process temperatures, where n≥2;

[0009] Based on Planck's blackbody radiation law, the emissivity matching ratio between each comparative process temperature and the corresponding measured temperature was calculated, and a relationship model between the emissivity matching ratio and the measured temperature was established.

[0010] For any measured temperature of the cavity to be matched, the corresponding emissivity matching ratio is obtained by interpolation based on the relationship model, and the calibration temperature of the cavity to be matched is calculated using the emissivity matching ratio obtained by interpolation.

[0011] In some embodiments, before obtaining the process result indicators of the reference cavity at each comparative process temperature, the following steps are further included:

[0012] The temperature measuring instruments of the reference cavity and the cavity to be matched are initially calibrated using temperature standard measuring instruments to obtain the first emissivity correction ratio ε1 of the temperature measuring instrument of the reference cavity and the second emissivity correction ratio ε2 of the temperature measuring instrument of the cavity to be matched.

[0013] In some embodiments, the i-th comparative process temperature among the n comparative process temperatures is T. i The measured temperature corresponding to the i-th process temperature is T. i ', then the corresponding emissivity matching ratio M i The calculation formula is:

[0014]

[0015] Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio.

[0016] In some embodiments, the step of obtaining the corresponding emissivity matching ratio based on the relational model for any measured temperature of the cavity to be matched, and calculating the calibration temperature of the cavity to be matched using the emissivity matching ratio obtained by interpolation, includes:

[0017] For any measured temperature T of the cavity to be matched k The corresponding emissivity matching ratio M is obtained by interpolation based on the relational model. k The interpolated emissivity matching ratio M k Substituting into the following formula, the calibration temperature T of the cavity to be matched is calculated. k :

[0018]

[0019] Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio.

[0020] In some embodiments, both the thermometer of the reference cavity and the thermometer of the cavity to be matched are infrared thermometers with a radiation wavelength range of 2.3 to 2.7 μm.

[0021] In some embodiments, when initial calibration is performed on the thermometers of the reference cavity and the cavity to be matched using temperature standard gauges, the total heating power of the reference cavity and the total heating power of the cavity to be matched are kept consistent.

[0022] In some embodiments, the process result index is the film growth rate.

[0023] In some embodiments, the relationship model is a linear regression model, which fits the global linear relationship between the emissivity matching ratio and the measured temperature using the least squares method.

[0024] In some embodiments, the relationship model is a piecewise linear model. The piecewise linear model divides the temperature range and independently fits the linear relationship between the emissivity matching ratio and the measured temperature in each temperature range. The temperature range is divided according to a preset temperature interval d, and satisfies d = 5m, where m is an integer and 1 ≤ m ≤ 10.

[0025] In some embodiments, the comparative process temperature of the reference cavity ranges from 400 to 1200°C.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] First, by introducing a comparison calibration mechanism between a reference cavity and a cavity to be matched, this invention effectively solves the problem that infrared thermometers may still cause deviations in process result indicators between different process cavities after initial calibration. This method significantly improves the consistency of process results between different process cavities in the same type of semiconductor equipment, providing a strong guarantee for the stability and reliability of semiconductor manufacturing processes.

[0028] Secondly, based on Planck's blackbody radiation law, this invention establishes a relationship model between measured temperature and emissivity matching ratio, thereby achieving precise calibration of any measured temperature of the cavity to be matched. This innovative method significantly reduces the influence of factors such as differences in mechanical assembly inside the cavity and temperature field-flow field coupling effect on the temperature measurement results, providing more accurate data support for process temperature control, which helps to accurately control the thin film deposition process on the substrate surface and ensures the quality stability of semiconductor products. Attached Figure Description

[0029] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the drawings described below are one embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0030] Figure 1 This is a schematic diagram of the structure of a semiconductor device provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of the epitaxial cavity provided in an embodiment of the present invention;

[0032] Figure 3 A flowchart of a temperature calibration method provided in an embodiment of the present invention;

[0033] Figures 1 to 3 The following reference numerals are included:

[0034] Reference cavity 1', matching cavity 1, transmission module 2, loading and locking cavity 3, equipment front-end module 4;

[0035] Upper liner 100, heating component 101, lower thermometer 102, upper flange 103, substrate 104, base 105, exhaust port 106, lower flange 107, lower dome 108, rotating support shaft 109, support bracket 110, pin 111, lower liner 112, air inlet 113, upper thermometer 114, preheating ring 115, upper dome 116. Detailed Implementation

[0036] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, further illustrates the solution proposed by the present invention. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, used only to facilitate and clearly illustrate the embodiments of the present invention. Please refer to the drawings to make the objectives, features, and advantages of the present invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the present invention, should still fall within the scope of the technical content disclosed in the present invention.

[0037] In actual semiconductor manufacturing, although process cavities of the same model adopt the same structural design, due to complex factors such as specific structural errors, differences in transmittance, and temperature-flow field coupling within the process cavity, the process results of different process cavities of the same model will still have certain differences under the same process conditions. In order to improve the consistency of process results of different process cavities of the same model under the same process conditions, it is necessary to calibrate the temperature measuring instruments of each process cavity of the same model.

[0038] Please see Figure 1 , Figure 1 A schematic diagram of a semiconductor device is shown. The device includes a front-end module 4 (EFEM), a load lock cavity 3, a transfer module 2 (TM), and several process cavities (PM). One of the process cavities is selected as a reference cavity 1', and the remaining process cavities are designated as matching cavities 1. The front-end module 4 is connected to the transfer module 2 via the load lock cavity 3. One or more containers, typically front-opening wafer transfer boxes from a cleanroom, are located on the opposite side of the front-end module 4 coupled to the load lock cavity 3. The transfer module 2 is coupled to the load lock cavity 3, which is maintained under vacuum. The transfer module 2 has a built-in robotic arm for transferring substrates between the load lock cavity 3 and the process cavities (reference cavity 1' and matching cavities 1). Several process cavities are coupled to the transfer module 2. These process cavities can be used to perform substrate-related processes and include, but are not limited to, chemical vapor deposition cavities, physical vapor deposition cavities, epitaxial cavities, etching cavities, thermal oxidation cavities, and thermal nitriding cavities.

[0039] It should be noted that the temperature calibration method of this application can not only match various process cavities of the same model in the same semiconductor equipment, but also match various process cavities of the same model between different semiconductor equipment; thereby reducing the deviation of process result indicators of various process cavities of the same model under the same process conditions, and making the consistency of process results of various process cavities of the same model reach the expected level.

[0040] In this process, a person skilled in the art needs to select one process cavity as a reference cavity 1' from the various process cavities of the same model to be calibrated, and the remaining process cavities are used as matching cavities 1. The reference cavity 1 can be used to calibrate each matching cavity 1'.

[0041] For example, the temperature calibration method of this application can be used to calibrate temperature measuring instruments of the same model for various epitaxial cavities; please refer to [link to relevant documentation]. Figure 2 , Figure 2A schematic diagram of a single epitaxial cavity is shown. The epitaxial cavity includes an upper dome 116 and a lower dome 108, both made of quartz. The upper dome 116 and the lower dome 108 enclose a sealed cavity. A base 105 for supporting a substrate 104 is disposed within the epitaxial cavity. Heating components 101 are disposed at the top and bottom of the epitaxial cavity. The heating components 101 provide heat energy to the epitaxial cavity using infrared radiation. The process temperature within the epitaxial cavity is changed by controlling the power of the heating components 101. An upper temperature sensor 114 and a lower temperature sensor 102 are disposed at the top and bottom of the epitaxial cavity, respectively. The upper temperature sensor 114 is used to monitor the temperature above the substrate 104, and the lower temperature sensor 102 is used to monitor the temperature below the base 105. The aforementioned extended cavity also includes an upper inner liner 100, a lower inner liner 112, an upper flange 103, and a lower flange 107. The upper inner liner 100 and the lower inner liner 112 are both quartz rings, respectively disposed inside the upper dome 116 and the lower dome 108. The upper inner liner 100 is positioned above the lower inner liner 112, and has an air inlet 113 for process gas passage and an exhaust outlet 106 opposite to the air inlet 113 on its sides. The upper dome 116 is connected to the upper flange 103, which fixes the upper dome 116 to the side wall. The lower dome 108 is connected to the lower flange 107, which fixes the lower dome 108 to the side wall. A rotating support shaft 109, a support bracket 110, and a pin 111 are provided below the base 105. The rotating support shaft 109 is used to support the rotation and lifting of the base 105. The support bracket 110 is used to support the pin 111 when the rotating support shaft 109 descends, thereby separating the substrate 104 from the base 105 during substrate transfer. A preheating ring 115 is also provided around the base 105 for preheating the process gas entering the epitaxial cavity.

[0042] Please see Figure 3 , Figure 3 A flowchart of the temperature calibration method of this application is shown; taking the calibration of various epitaxial cavities of the same model as an example (the various epitaxial cavities of the same model can be in the same semiconductor device or in different semiconductor devices), one epitaxial cavity is selected as the reference cavity 1' among the various epitaxial cavities of the same model, and the remaining epitaxial cavities are used as the cavity 1 to be matched.

[0043] The temperature calibration method of this application includes the following steps:

[0044] S1. Set n comparison process temperatures, obtain the process result index of the reference cavity at each comparison process temperature, and obtain the measured temperature required for the cavity to be matched to achieve the same process result index, thereby obtaining n measured temperatures that correspond one-to-one with each of the comparison process temperatures, where n≥2.

[0045] For example, as shown in Table 1 below, three comparison process temperatures (610, 637, 725) can be preset, and the process result indicators of the reference cavity at each comparison process temperature can be obtained. The measured temperatures (613.9, 640.4, 726.4) required for the cavity to be matched to achieve the same process result indicators can also be obtained, resulting in three sets of comparison process temperatures and their corresponding measured temperatures.

[0046]

[0047] Table 1. Comparison process temperatures of reference cavities and their corresponding measured temperatures of the cavities to be matched.

[0048] As shown in Table 1 above, before the process result index feedback calibration is performed, there is a certain temperature difference between the reference cavity and the cavity to be matched. This temperature difference will affect the consistency of the process result index, thus causing the process result to not meet expectations.

[0049] S2. Based on Planck's blackbody radiation law, calculate the emissivity matching ratio between each comparative process temperature and the corresponding measured temperature, and establish a model relating the emissivity matching ratio to the measured temperature.

[0050] For example, as shown in Table 2 below, based on Planck's blackbody radiation law, the emissivity matching ratios corresponding to the three sets of comparative process temperatures and measured temperatures are calculated respectively; and a relationship model between the emissivity matching ratio and the measured temperature can be established based on the three measured temperatures and the calculated corresponding emissivity matching ratios.

[0051]

[0052] Table 2. Emissivity matching ratio calculated by comparing process temperature and measured temperature in each group.

[0053] S3. For any measured temperature of the cavity to be matched, the corresponding emissivity matching ratio is obtained by interpolation based on the relationship model, and the calibration temperature of the cavity to be matched is calculated using the emissivity matching ratio obtained by interpolation.

[0054] For example, the measured temperature of the cavity to be matched is 682.5°C, and the emissivity matching ratio corresponding to the measured temperature of 682.5°C is obtained by interpolation based on the relational model. The calibration temperature of the cavity to be matched is 680°C. After calibration by feedback of process result indicators, the temperature difference between the cavity to be matched and the reference cavity can be controlled within ±1, that is, the absolute value of the temperature difference does not exceed 1.

[0055] By introducing a comparison calibration mechanism between a reference cavity and a cavity to be matched, the temperature calibration method of this application effectively solves the problem of deviation in process result indicators between different process cavities, and improves the consistency of process results between different process cavities in the same type of semiconductor equipment.

[0056] Optionally, before obtaining the process result indicators of the reference cavity at each comparative process temperature, the following steps are also included:

[0057] The temperature measuring instruments of the reference cavity and the cavity to be matched are initially calibrated using temperature standard measuring instruments to obtain the first emissivity correction ratio ε1 of the temperature measuring instrument of the reference cavity and the second emissivity correction ratio ε2 of the temperature measuring instrument of the cavity to be matched.

[0058] Taking the extensional cavity as an example, such as Figure 2 As shown, an upper temperature sensor 114 and a lower temperature sensor 102 are provided at the top and bottom of the epitaxial cavity. The upper temperature sensor 114 is used to monitor the temperature above the substrate 104, and the lower temperature sensor 102 is used to monitor the temperature below the base 105.

[0059] We select one epitaxial cavity from all epitaxial cavities of the same model as the reference cavity, and the remaining epitaxial cavities as the cavities to be matched;

[0060] Therefore, a first upper temperature measuring instrument and a first lower temperature measuring instrument are respectively installed at the top and bottom of the reference cavity; a second upper temperature measuring instrument and a second lower temperature measuring instrument are respectively installed at the top and bottom of the cavity to be matched.

[0061] The total heating power of the reference cavity is set to P, and the reference temperature T of the reference cavity is measured using a temperature standard measuring instrument. c The temperature T was measured using the first upper thermometer. t The first emissivity correction factor ε1' of the first upper thermometer is calculated using the following formula:

[0062]

[0063] Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, and k is Boltzmann's constant;

[0064] The measurement temperature of the first upper thermometer is calibrated using the first emissivity correction factor ε1';

[0065] Temperature T was measured using the first thermometer. b The first emissivity correction ratio ε1 of the first lower thermometer is calculated using the following formula:

[0066]

[0067] Among them, T t 'The measured temperature of the first upper thermometer after calibration;

[0068] The first lower thermometer is calibrated using the first emissivity correction ratio ε1.

[0069] Similarly, the total heating power of the cavity to be matched is set to P (i.e., the total heating power of the cavity to be matched is consistent with the total heating power of the reference cavity), and calibration is performed using a temperature standard measuring instrument to obtain the second emissivity correction factor ε2' of the second upper thermometer and the second emissivity correction ratio ε2 of the second lower thermometer of the cavity to be matched; the calculation process of the second emissivity correction factor ε2' of the second upper thermometer and the second emissivity correction ratio ε2 of the second lower thermometer can refer to the calculation process of the first emissivity correction factor ε1' of the first upper thermometer and the first emissivity correction ratio ε1 of the first lower thermometer described above, and will not be repeated here.

[0070] Optionally, the i-th comparative process temperature among the n comparative process temperatures is T. i The measured temperature corresponding to the i-th process temperature is T. i ', then the corresponding emissivity matching ratio M i The calculation formula is:

[0071]

[0072] Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio.

[0073] Optionally, the step of obtaining the corresponding emissivity matching ratio based on the relationship model for any measured temperature of the cavity to be matched, and calculating the calibration temperature of the cavity to be matched using the interpolated emissivity matching ratio, includes:

[0074] For any measured temperature T of the cavity to be matched k The corresponding emissivity matching ratio M is obtained by interpolation based on the relational model. k The interpolated emissivity matching ratio M k Substituting into the following formula, the calibration temperature T of the cavity to be matched is calculated. k :

[0075]

[0076] Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio.

[0077] Optionally, both the reference cavity's thermometer and the cavity to be matched can be infrared thermometers with a radiation wavelength range of 2.3–2.7 μm.

[0078] Optionally, when performing initial calibration of the temperature measuring instruments for the reference cavity and the cavity to be matched using temperature standard measuring instruments, the total heating power of the reference cavity and the total heating power of the cavity to be matched should be kept consistent.

[0079] Preferably, the process result index is the film growth rate, which is the thickness of the film deposited on the substrate surface per unit time.

[0080] Optionally, the relationship model is a linear regression model, which fits the global linear relationship between the emissivity matching ratio and the measured temperature using the least squares method.

[0081] Optionally, the relationship model is a piecewise linear model. The piecewise linear model divides the temperature range and independently fits the linear relationship between the emissivity matching ratio and the measured temperature in each temperature range. The temperature range is divided according to a preset temperature interval d, and satisfies d = 5m, where m is an integer and 1 ≤ m ≤ 10.

[0082] For example, the preset temperature interval d can be 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50. A smaller preset temperature interval d can make the relational model more accurate.

[0083] Optionally, the reference chamber's comparative process temperature range is 400–1200℃.

[0084] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. All devices selected in this application (components without specific structural descriptions) are general standard parts or components known to those skilled in the art, and their structures and principles are known to those skilled in the art through technical manuals or conventional experimental methods. Furthermore, the term "connection" in this document refers to a direct connection between A and B, or an indirect connection between A and B. An indirect connection includes connections between A and B via C, or even via C and D, and other components. The connection between A and B can be integral or separate, detachable or fixed. Moreover, those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination. The term "optional" in this document indicates that the technical feature can be combined with or not combined with any feature herein.

[0085] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A temperature calibration method for a semiconductor device, said semiconductor device comprising a reference cavity and a cavity to be matched, characterized in that, Includes the following steps: Set n comparison process temperatures, obtain the process result index of the reference cavity at each comparison process temperature, and obtain the measured temperature required for the cavity to be matched to achieve the same process result index, thereby obtaining n measured temperatures that correspond one-to-one with each of the comparison process temperatures, where n≥2; Based on Planck's blackbody radiation law, the emissivity matching ratio between each comparative process temperature and the corresponding measured temperature was calculated, and a relationship model between the emissivity matching ratio and the measured temperature was established. For any measured temperature of the cavity to be matched, the corresponding emissivity matching ratio is obtained by interpolation based on the relationship model, and the calibration temperature of the cavity to be matched is calculated using the emissivity matching ratio obtained by interpolation. in, The reference cavity is equipped with a first upper temperature measuring instrument and a first lower temperature measuring instrument at its top and bottom, respectively; the cavity to be matched is equipped with a second upper temperature measuring instrument and a second lower temperature measuring instrument at its top and bottom, respectively; before obtaining the process result indicators of the reference cavity at each comparative process temperature, the following steps are also included: The temperature measuring instruments of the reference cavity and the cavity to be matched are initially calibrated using temperature standard measuring instruments to obtain the first emissivity correction ratio ε1 of the temperature measuring instrument of the reference cavity and the second emissivity correction ratio ε2 of the temperature measuring instrument of the cavity to be matched. The first emissivity correction ratio ε1 is obtained in the following way: The total heating power of the reference cavity is set to P, and the reference temperature T of the reference cavity is measured using a temperature standard measuring instrument. c The temperature T was measured using the first upper thermometer. t The first emissivity correction factor ε1' of the first upper thermometer is calculated using the following formula: ； Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, and k is Boltzmann's constant; The measurement temperature of the first upper thermometer is calibrated using the first emissivity correction factor ε1'; Temperature T was measured using the first thermometer. b The first emissivity correction ratio ε1 of the first lower thermometer is calculated using the following formula: ； Among them, T t ' The measured temperature of the first upper thermometer after calibration; The first lower thermometer is calibrated using the first emissivity correction ratio ε1. The second emissivity correction ratio ε2 is obtained in the following way: The total heating power of the cavity to be matched is set to P, so that the total heating power of the cavity to be matched is consistent with the total heating power of the reference cavity. The cavity is calibrated using a temperature standard measuring instrument to obtain the second emissivity correction factor ε2' of the second upper thermometer and the second emissivity correction ratio ε2 of the second lower thermometer. The calculation process of the second emissivity correction factor ε2' of the second upper thermometer and the second emissivity correction ratio ε2 of the second lower thermometer is the same as the calculation process of the first emissivity correction factor ε1' of the first upper thermometer and the first emissivity correction ratio ε1 of the first lower thermometer. The i-th comparative process temperature among the n comparative process temperatures is T. i The measured temperature corresponding to the i-th process temperature is T. i ', then the corresponding emissivity matching ratio M i The calculation formula is: Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio; The steps of obtaining the corresponding emissivity matching ratio by interpolation based on the relationship model for any measured temperature of the cavity to be matched, and calculating the calibration temperature of the cavity to be matched using the interpolated emissivity matching ratio, include: For any measured temperature T of the cavity to be matched k Based on the relationship model, the corresponding emissivity matching ratio M is obtained through interpolation. k The interpolated emissivity matching ratio M k Substituting into the following formula, the calibration temperature T of the cavity to be matched is calculated. k : Where h is Planck's constant, c is the speed of light, λ is the thermometry wavelength, k is Boltzmann's constant, ε1 is the first emissivity correction ratio, and ε2 is the second emissivity correction ratio.

2. The temperature calibration method as described in claim 1, characterized in that, Both the reference cavity's thermometer and the cavity to be matched are infrared thermometers with a radiation wavelength range of 2.3~2.7μm.

3. The temperature calibration method as described in claim 1, characterized in that, When performing initial calibration of the temperature measuring instruments for the reference cavity and the cavity to be matched using temperature standard measuring instruments, the total heating power of the reference cavity and the total heating power of the cavity to be matched are kept consistent.

4. The temperature calibration method as described in claim 1, characterized in that, The process result index is the film growth rate.

5. The temperature calibration method as described in claim 1, characterized in that, The relationship model is a linear regression model, which fits the global linear relationship between the emissivity matching ratio and the measured temperature using the least squares method.

6. The temperature calibration method as described in claim 1, characterized in that, The relationship model is a piecewise linear model. The piecewise linear model divides the temperature range and independently fits the linear relationship between the emissivity matching ratio and the measured temperature in each temperature range. The temperature range is divided according to a preset temperature interval d and satisfies d=5m, where m is an integer and 1≤m≤10.

7. The temperature calibration method as described in claim 1, characterized in that, The reference cavity has a comparison process temperature range of 400~1200℃.

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