Method and device for measuring temperature of wafer surface

Abstract

The present invention provides a method and device for measuring the temperature of a wafer surface, belonging to the technical field of semiconductor manufacturing. The method for measuring the temperature of a wafer surface provided by the present invention includes baking a fluorescent indicator at different preset temperatures, calibrating the temperature of the fluorescent indicator after baking for different time periods at the same temperature; heating the wafer provided with the fluorescent indicator, wherein the fluorescent indicators are distributed at intervals at preset positions on the wafer; obtaining the temperature of the fluorescent indicator on the wafer; obtaining the heating temperature and heating time of the fluorescent indicator according to the baking temperature of the fluorescent indicator, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time of the corresponding position on the wafer surface. This method for measuring the temperature of a wafer surface can simultaneously obtain the temperature of the wafer surface and the time when the wafer is heated, and can obtain the true thermal power absorbed by the wafer surface.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor manufacturing, and more specifically, relates to a method and device for measuring the temperature of a wafer surface. Background Art

[0002] During the semiconductor manufacturing process, the wafer temperature is a crucial parameter, which directly affects the quality and stability of various processing technologies on the wafer. Reasonably controlling the wafer temperature can improve the performance and reliability of semiconductor devices, and reduce the failure rate and cost of products. For example, uneven wafer temperature distribution will lead to too large a temperature gradient during the manufacturing process, thereby affecting the device quality and performance on the wafer. Therefore, in the actual semiconductor processing process, it is necessary to measure the wafer surface temperature, and then control the uniformity of the wafer temperature by reasonably designing the manufacturing process and optimizing the equipment parameters to ensure the consistency of the devices on the entire wafer.

[0003] The existing wafer temperature measurement methods generally use wired thermocouple wafers (TC Wafers) and wireless temperature measurement wafers. The wired TC Wafer uses a thermocouple TC as a temperature sensor, which is connected to a temperature collector or a host computer through a lead wire, and can measure the temperature within a range of nearly 1000 degrees. The thermocouple has a simple structure, convenient operation, and easy installation. However, because the thermocouple measurement requires an external wire to the outside of the wafer processing chamber, a vacuum penetrator needs to be designed, and the thermocouple can only achieve a single point in measurement space and time. For a wafer, it can only measure the temperature parameter of a certain moment on the wafer surface, and cannot give the true thermal power absorbed by the wafer surface (thermal power is a combined effect of time and temperature). The wireless temperature measurement wafer integrates an electronic temperature measurement chip and a wireless module on the wafer, and can transmit the temperature signal to a temperature collector or a host computer through wireless communication, but it cannot measure high temperatures, and its service life is much lower than that of wired products. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and device for measuring the temperature of a wafer surface, which can obtain the heating temperature and heating time at a preset position on the wafer surface.

[0005] To achieve the above object, the technical solution adopted by the present invention is: In the first aspect of the present invention, a method for measuring the temperature of a wafer surface is provided, including:

[0006] Roasting a fluorescent indicator at different preset temperatures, and calibrating the temperature of the fluorescent indicator after roasting for different time periods at the same temperature;

[0007] Heating a wafer provided with the fluorescent indicator, wherein the fluorescent indicators are distributed at intervals on the preset positions of the wafer;

[0008] Obtaining the temperature of the fluorescent indicator on the wafer;

[0009] Obtain the heating temperature and heating time of the fluorescent indicator based on the calcination temperature of the fluorescent indicator, the temperature of the fluorescent indicator after calcination for different time periods, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time of the corresponding position on the wafer surface.

[0010] In one embodiment, in the step of calcining the indicator at different preset temperatures and obtaining the temperature of the indicator after calcination for different time periods at the same temperature, the different preset temperatures increase in a preset temperature interval, and the different time periods increase in a preset time interval.

[0011] In one embodiment, when heating the wafer provided with the indicator, where the indicators are distributed at intervals on preset positions of the wafer, the preset positions are a plurality of cavities arranged at intervals on the wafer surface.

[0012] In one embodiment, when heating the wafer provided with the indicator, the wafer is heated by a heat spreader, a heating plate or a constant temperature bath.

[0013] In one embodiment, the indicator is a fluorescent material.

[0014] A second aspect of the present invention provides a wafer surface temperature measuring device, including a wafer, an indicator, a heating structure and a temperature measuring structure;

[0015] A plurality of cavities are formed on the wafer surface, the cavities are arranged at intervals, the cavities are used to accommodate the fluorescent indicator, and the temperature measuring structure is used to obtain the temperature of the fluorescent indicator after the wafer is heated, so as to obtain the heating temperature and heating time of the fluorescent indicator according to the calcination time of the fluorescent indicator calibrated in the above-mentioned wafer surface temperature measuring method, the temperature of the fluorescent indicator after calcination for different time periods, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time of the corresponding position on the wafer surface.

[0016] In one embodiment, the cavity is a blind hole formed on the same surface of the wafer, and the blind holes are arranged at equal intervals.

[0017] In one embodiment, the cavities are arranged in an array on the wafer surface; or the cavities are evenly distributed at intervals along the circumferential direction of the center of the wafer.

[0018] In one embodiment, the fluorescent indicator is KLa(MoO4) 2+ , Eu 3+ :La2O2S, Cr:YAG, Nd:Glass, Cr 3 +: LiSrAlF6, Cr:Al2O3, Nd:YAG, Cr:BeAl2O3; or the fluorescent indicator is a fluorescent material doped with Nd 3+ of the fluorescent material, doped with Tm 3+ of the fluorescent material, doped with Er 3+ of the fluorescent material, or doped with Cr 3+ of the fluorescent material.

[0019] In one embodiment, a window is provided on the cavity, and the window is used to observe the change of the fluorescent indicator.

[0020] In one embodiment, the window is a quartz window, a sapphire window, a magnesium aluminate spinel window, or an aluminum oxynitride window; the window is bonded to the surface of the wafer.

[0021] In one embodiment, the window is parallel to the surface of the wafer, and the window is higher than the surface of the wafer or flush with the surface of the wafer.

[0022] In one embodiment, the outer contour of the opening of the cavity is circular, and the diameter of the circle is 1 - 10 mm;

[0023] Or, the outer contour of the opening of the cavity is rectangular, and the length or width of the rectangle is 1 - 10 mm;

[0024] The filling thickness of the fluorescent indicator inside the cavity is 0.1 - 0.5 mm.

[0025] In one embodiment, the temperature measurement structure is a fluorescent optical fiber temperature measurement structure, and the temperature measurement structure includes an optical fiber probe and a temperature measurement display platform. One end of the optical fiber probe is connected to the temperature measurement display platform, and the other end of the optical fiber probe is used to obtain the optical signal of the fluorescent indicator.

[0026] The wafer surface temperature measurement method provided by the present invention includes baking the fluorescent indicator at different preset temperatures, calibrating the temperature of the fluorescent indicator after baking for different time periods at the same temperature; heating the wafer provided with the fluorescent indicator, wherein the fluorescent indicators are distributed at intervals at preset positions on the wafer; obtaining the temperature of the fluorescent indicator on the wafer; obtaining the heating temperature and heating time of the fluorescent indicator according to the baking temperature of the fluorescent indicator, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time of the corresponding position on the wafer surface. This wafer surface temperature measurement method can simultaneously obtain the temperature of the wafer surface and the time when the wafer is heated, and can obtain the true thermal power absorbed by the wafer surface.

[0027] The wafer surface temperature measurement device provided by the present invention includes a wafer, a fluorescent indicator, and a temperature measurement structure. A plurality of cavities are formed on the surface of the wafer, and the cavities are arranged at intervals. The cavities are used to accommodate the fluorescent indicator. The temperature measurement structure is used to measure the temperature of the fluorescent indicator after heating the wafer, so as to obtain the heating temperature and heating time of the fluorescent indicator according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, thereby obtaining the heating temperature and heating time of the corresponding position on the wafer surface. This wafer surface temperature measurement device can simultaneously obtain the temperature of the wafer surface and the time when the wafer is heated, thereby obtaining the true thermal power absorbed by the wafer surface. Moreover, it does not require the use of an electronic temperature measurement chip and a wireless module, improving the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a flowchart of the wafer surface temperature measurement method provided by the embodiment of the present invention;

[0030] Figure 2 It is a schematic structural diagram of the wafer surface temperature measurement device provided by the embodiment of the present invention;

[0031] Figure 3 It is a top view of the wafer and the cavities formed on the wafer of the wafer surface temperature measurement device provided by the embodiment of the present invention;

[0032] Figure 4 It is a schematic structural diagram of the cavities and windows formed on the wafer of the wafer surface temperature measurement device provided by the embodiment of the present invention;

[0033] Figure 5 It is a top view of the wafer and the cavities formed on the wafer of the wafer surface temperature measurement device provided by the embodiment of the present invention.

[0034] Among them, the reference numerals in the drawings are as follows:

[0035] 1 - wafer; 2 - fluorescent indicator; 3 - temperature measurement structure; 11 - cavity; 12 - window; 31 - optical fiber probe; 32 - temperature measurement display platform. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] To make the objectives, technical solutions, and advantages of the embodiments 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 in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] In the description of the present invention, it should be understood that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily limit to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0038] It should be understood that the orientation or positional relationships indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0039] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. It should be understood that the term "and / or" used herein is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, both A and B exist simultaneously, and B exists alone. In the description of the present invention, unless otherwise specified, the meaning of "plural" is two or more.

[0040] The existing wafer temperature measurement methods generally use wired thermocouple wafers (TC Wafers) and wireless temperature measurement wafers. The advantage of wireless temperature measurement wafers compared to wired TC Wafers is that they can measure temperature wirelessly, without the need to stop the machine and open the semiconductor process chamber. They can directly transfer the wafer to the position where temperature measurement is required, such as the chuck, furnace tube, etc., through the robot online, reducing the maintenance time and improving the usage efficiency. The disadvantage is that they cannot measure high temperatures, especially above 500 degrees Celsius, where currently no electronic chips can work properly, and the usage time and product life are also much lower than those of wired products.

[0041] At present, the high-temperature wireless measurement technologies mainly include infrared pyrometer temperature measurement, pyrometric cone temperature measurement, temperature measurement block temperature measurement, and molten metal indicator temperature measurement. Infrared pyrometer temperature measurement measures the surface temperature of an object through the blackbody radiation method. However, it is necessary to design an installation position and an observation window for it on the cavity. Since the infrared emissivity corresponding to different materials is different, separate calibration is required. Pyrometric cone or temperature measurement block temperature measurement can monitor the temperature and time of heating materials in a furnace through temperature measurement blocks or pyrometric cones. The heating materials are affected not only by temperature but also by the time exposed to that temperature. Through temperature measurement blocks or pyrometric cones, the amount of energy transfer during the heating process can be measured, that is, the so-called heat work (heat work is the combined effect of time and temperature). During testing, the shrinkage of the temperature measurement block or the bending position of the pyrometric cone during heating can be measured, and then the heating time and temperature parameters can be deduced by looking up the table. For pyrometric cone and temperature measurement block temperature measurement methods, temperature measurement cones or temperature measurement blocks with different component ratios are used during temperature measurement to measure different ranges of temperatures, and then the specific temperature parameters are inferred based on the size change of the temperature measurement block or the bending angle change of the pyrometric cone. Molten metal indicator temperature measurement can indicate the temperature parameters of the wafer plane. However, the change in the melting point of the metal indicator is controlled by adjusting the components of the indicator. Therefore, this test method requires pre-adjusting the components of the metal indicator in each cavity and calibration in advance, which occupies a large volume and the metal indicator is heavy. Based on the above problems, this application provides a wafer surface temperature measurement method and device.

[0042] The wafer surface temperature measurement method and device provided by the present invention will be described in detail below in conjunction with specific embodiments.

[0043] Figure 1 The flowchart of the wafer surface temperature measurement method provided by the embodiment of the present invention is shown in Figure 1 As shown, in the first aspect of this embodiment, a wafer surface temperature measurement method is provided, including:

[0044] S101. Bake the fluorescent indicator at different preset temperatures and calibrate the temperature of the fluorescent indicator after baking for different time periods at the same temperature;

[0045] Specifically, in this embodiment, calcining the fluorescent indicator at different preset temperatures means calcining the fluorescent indicator at different temperature gradients, and recording the temperature values of the fluorescent indicator at a specific temperature when the calcination time at the same temperature value is different. Table 1 shows the temperatures of the corresponding fluorescent indicators at different temperatures and different calcination times. For example, after the fluorescent indicator is calcined at 1000 °C for 30 min, 60 min, 90 min, 120 min, 150 min, 160 min, and 180 min, the temperatures of the fluorescent indicator at room temperature are a1, a2, a3, a4, a5. Then, the fluorescent indicator is calcined at 1100 °C, 1150 °C, 1200 °C, and 1250 °C for 30 min, 60 min, 90 min, 120 min, 150 min, 160 min, and 180 min respectively, and the temperature of the fluorescent agent at room temperature is measured and recorded. The temperature of the fluorescent indicator at room temperature is measured by an optical fiber probe.

[0046]

[0047] Table 1

[0048] In order to improve the accuracy of the calibration of the fluorescent indicator in this embodiment, for example, the temperatures a1, a2, a3, a4, a5 are the average values obtained from multiple repeated tests of calcining the fluorescent indicator at 1000 °C for 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min. For example, a1 is the average value taken after multiple groups of fluorescent indicators are calcined at 1000 °C for 30 min.

[0049] The temperatures b1, b2, b3, b4, b5 are the average values obtained from multiple repeated tests of calcining the fluorescent indicator at 1100 °C for 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min.

[0050] The temperatures c1, c2, c3, c4, c5 are the average values obtained from multiple repeated tests of calcining the fluorescent indicator at 1150 °C for 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min.

[0051] The temperatures d1, d2, d3, d4, d5 are the average values obtained from multiple repeated tests of calcining the fluorescent indicator at 1200 °C for 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min.

[0052] The temperatures e1, e2, e3, e4, and e5 are the average values obtained from multiple repeated tests of the fluorescent indicator calcined at 1250°C for 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min respectively.

[0053] S102. Heat the wafer with the fluorescent indicator provided, where the fluorescent indicators are distributed at intervals on the preset positions of the wafer.

[0054] Specifically, the fluorescent indicators in this embodiment are distributed at intervals on the preset positions of the wafer. For example, the fluorescent indicators are arranged in an array on the surface of the wafer; or the fluorescent indicators are evenly distributed at intervals along the circumference of the center of the wafer. In this embodiment, by distributing the fluorescent indicators at intervals on the preset positions of the wafer, the heating temperature and heating time at the preset positions of the wafer are obtained through the temperature of the indicator at each preset position, so as to obtain the temperature distribution of the entire wafer surface, helping the operator to comprehensively understand the temperature condition of the wafer. In this embodiment, a heat spreader, a heating plate or a constant temperature bath can be used to heat the wafer. Exemplarily, cavities are formed at the preset positions on the surface of the wafer in this embodiment, and the fluorescent indicators are located in the cavities.

[0055] In this embodiment, the fluorescent indicator in "the fluorescent indicators are distributed at intervals" is the same kind of indicator as the calibrated fluorescent indicator, but the fluorescent indicator in "the fluorescent indicators are distributed at intervals" cannot be the fluorescent indicator used in the calibration process.

[0056] S103. Obtain the temperature of the fluorescent indicator on the wafer.

[0057] Specifically, after heating the wafer for a certain time, measure the temperature of the fluorescent indicator on the wafer. In this embodiment, the temperature of the fluorescent indicator on the wafer is measured by an optical fiber probe at room temperature.

[0058] S104. Obtain the heating temperature and heating time of the fluorescent indicator according to the calcination time calibrated by the fluorescent indicator, the temperature of the corresponding fluorescent indicator, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time at the corresponding positions on the wafer surface.

[0059] Specifically, according to Table 1 of temperature conversion, the heating time and heating temperature of the fluorescent indicator in each wafer cavity can be deduced from the temperature of the fluorescent indicator in the cavity formed on the wafer surface, and the heating temperature and heating time at the preset positions on the corresponding wafer surface are obtained.

[0060] Table 1 in the above embodiment shows the temperature of the fluorescent indicator obtained after the fluorescent indicator is calcined at 1000°C, 1100°C, 1150°C, 1200°C, and 1250°C for 30 min, 60 min, 90 min, 120 min, 150 min, 160 min, and 180 min, respectively. Of course, the temperature gradient and the heating time interval can be further adjusted in other calibration processes. For example, the starting temperature is 800°C, and the calcination is performed at different preset temperatures, and then the different preset temperatures are increased at intervals of 25 degrees Celsius. For the same preset temperature, the calcination temperature can be increased at intervals of 30 minutes.

[0061] This embodiment can obtain more calibration values ​​by reducing the preset temperature interval and the preset time interval. In this embodiment, when the temperature values ​​calibrated in Table 1 are the same when calcined at different temperatures during the calibration process, the calibration can be re-performed by replacing different types of fluorescent indicators.

[0062] In the CVD process, the uniformity and accuracy of temperature have an important influence on the quality and yield of thin film coating. Therefore, it is necessary to test the temperature in the CVD machine chamber during the CVD installation process, calibration test process or abnormal cause analysis process. The existing CVD chamber temperature detection generally adopts a TC wafer temperature measurement system. The principle is to embed a high temperature sensor thermocouple at a specific position on the wafer surface through a special processing technology to obtain the actual temperature measurement value of the specific position of the wafer and the temperature distribution of the entire wafer. However, the TC wafer temperature measurement system requires an external wire to the outside of the CVD chamber, a vacuum through-hole needs to be designed, and the chamber needs to be shut down. In addition, the thermocouple can only measure a point in space and time, that is, for the wafer, it can only measure the temperature parameters of the wafer surface at a certain moment, and cannot give the actual heat work absorbed by the wafer surface. The wafer surface temperature measurement method of this embodiment can obtain the heating temperature and heating time of the indicator according to the calibrated baking time of the indicator, the temperature of the corresponding indicator and the temperature of the indicator on the wafer, and obtain the heating temperature and heating time of the corresponding position of the wafer. That is, the wafer surface temperature measurement method of this embodiment can simultaneously indicate the temperature of the wafer surface and the time when the wafer is heated, and can obtain the actual heat work absorbed by the wafer surface, helping operators to fully understand the temperature status of the wafer surface.

[0063] The wafer surface temperature measurement method provided in this embodiment includes baking a fluorescent indicator at different preset temperatures, calibrating the temperature of the fluorescent indicator after baking for different periods of time at the same temperature; heating the wafer provided with the fluorescent indicator, wherein the fluorescent indicator is distributed at preset positions on the wafer at intervals; obtaining the temperature of the fluorescent indicator on the wafer; obtaining the heating temperature and heating time of the fluorescent indicator according to the baking temperature of the fluorescent indicator, the temperature of the fluorescent indicator after baking for different periods of time, and the temperature of the fluorescent indicator on the wafer, so as to obtain the heating temperature and heating time of the corresponding position on the wafer surface. This wafer surface temperature measurement method can obtain the temperature of the wafer surface and the heating time of the wafer at the same time, and can obtain the true thermal power absorbed by the wafer surface.

[0064] Figure 2 FIG. is a schematic structural diagram of a wafer surface temperature measurement device provided in an embodiment of the present invention. Figure 3 FIG. is a top view of a wafer and a cavity formed on the wafer of the wafer surface temperature measurement device provided in an embodiment of the present invention. Please refer to Figure 2 and Figure 3 As shown in FIGS., a second aspect of this embodiment provides a wafer surface temperature measurement device, including a wafer 1, a fluorescent indicator 2, and a temperature measurement structure 3.

[0065] A plurality of cavities 11 are formed on the surface of the wafer 1, the cavities 11 are arranged at intervals, the cavities 11 are used to accommodate the fluorescent indicator 2, and the temperature measurement structure 3 is used to obtain the temperature of the fluorescent indicator 2 after the wafer 1 is heated, so as to obtain the heating temperature and heating time of the fluorescent indicator 2 according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method as described in the above embodiment, the temperature of the fluorescent indicator after baking for different periods of time, and the temperature of the fluorescent indicator 2 on the wafer 1, so as to obtain the heating temperature and heating time of the corresponding position on the wafer 1 surface.

[0066] The wafer surface temperature measurement device of this embodiment can be applied to the temperature detection of the reaction chamber of a CVD device. The wafer surface temperature measurement device obtains the heating temperature and heating time of the fluorescent indicator 2 according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method as described in the above embodiment, the corresponding temperature of the fluorescent indicator, and the temperature of the fluorescent indicator 2 on the wafer 1, so as to obtain the heating temperature and heating time of the corresponding position on the wafer 1. After obtaining the heating temperature, heating time and the temperature distribution of the entire wafer 1 at a specific position. These temperature data can help engineers evaluate the stability of the CVD process, track temperature changes, and adjust process parameters, so as to ensure the quality and performance of CVD process products.

[0067] In this embodiment, there is no special limitation on the size of the wafer 1, and the size of the wafer 1 can be preset in advance according to the size of the wafer 1 processed by the CVD equipment. A plurality of cavities 11 are formed on the surface of the wafer 1, and the cavities 11 are arranged at intervals. The cavities 11 are used to accommodate the fluorescent indicator 2. In this embodiment, the cavities 11 formed on the surface of the wafer 1 are used to load the fluorescent indicator 2. In this embodiment, there is no special limitation on the outer contour shape of the cavities 11. In this embodiment, a plurality of cavities 11 for accommodating the fluorescent indicator 2 are formed at different positions on the surface of the wafer 1, and the temperature of the surface of the wafer 1 is obtained by obtaining the temperature of the fluorescent indicator 2.

[0068] In this embodiment, there is no special limitation on the specific material of the fluorescent indicator 2. Exemplarily, the fluorescent indicator 2 can be KLa(MoO4) 2+ , Eu 3+ :La2O2S, Cr:YAG, Nd:Glass, Cr 3+ :LiSrAlF6, Cr:Al2O3, Nd:YAG, Cr:BeAl2O3; or the fluorescent indicator is a fluorescent material doped with Nd 3+ , a fluorescent material doped with Tm 3+ , a fluorescent material doped with Er 3+ , or a fluorescent material doped with Cr 3+ .

[0069] The temperature measurement structure 3 in this embodiment is used to measure the temperature of the fluorescent indicator 2 after the wafer 1 is heated. In this embodiment, there is no special limitation on the specific structure of the temperature measurement structure 3, as long as it can measure the temperature of the fluorescent indicator 2 at the corresponding position after heating the wafer 1. Exemplarily, the temperature measurement structure 3 includes an optical fiber probe 31 and a temperature measurement display platform 32. One end of the optical fiber probe 31 in this embodiment is connected to the temperature measurement display platform 32, and the other end is used to obtain the optical signal of the fluorescent indicator 2.

[0070] The wafer surface temperature measurement device provided in this embodiment includes a wafer, a fluorescent indicator, and a temperature measurement structure. A plurality of cavities are formed on the surface of the wafer, and the cavities are arranged at intervals. The cavities are used to accommodate the fluorescent indicator. The temperature measurement structure is used to measure the temperature of the fluorescent indicator after heating the wafer, so as to obtain the heating temperature and heating time of the fluorescent indicator according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, thereby obtaining the heating temperature and heating time of the corresponding position on the wafer surface. This wafer surface temperature measurement device can simultaneously obtain the temperature of the wafer surface and the time when the wafer is heated, thereby obtaining the true thermal power absorbed by the wafer surface, and does not require the use of an electronic temperature measurement chip and a wireless module, improving the service life.

[0071] In a specific embodiment, the cavity 11 is a blind hole formed on the same surface of the wafer 1, and the blind holes are arranged at equal intervals. In this embodiment, the cavity 11 is formed by opening blind holes on the same surface of the wafer 1, without the need to add other materials on the upper part of the wafer 1 to make the cavity, and the manufacturing method of the cavity 11 is simple.

[0072] Optionally, the cavities 11 are arranged in an array on the surface of the wafer 1; or the cavities 11 are evenly spaced along the circumferential direction of the center of the wafer 1. Exemplarily, please refer to Figure 3 , the cavities 11 are arranged in multiple rows and columns, and the distance between every two cavities 11 is equal. The cavities 11 in this embodiment are evenly spaced on the wafer 1. By measuring the temperature of the fluorescent indicator 2 in the cavity 11, it is equivalent to obtaining the temperature at the corresponding position on the wafer 1, so as to obtain the temperature distribution of the entire surface of the wafer 1. After the analysis system obtains the temperature at the corresponding position on the wafer 1, it can draw a temperature distribution map of the surface of the wafer 1 to help the operator comprehensively understand the temperature condition on the wafer 1.

[0073] Figure 4 FIG. [ID] is a schematic structural diagram of the cavity and the window opened on the wafer of the wafer surface temperature measuring device provided by the embodiment of the present invention, Figure 5 FIG. [ID] is a top view of the wafer and the cavity opened on the wafer of the wafer surface temperature measuring device provided by the embodiment of the present invention. Please refer to Figure 4 and Figure 5 , further, a window 12 is provided on the cavity 11, and the window 12 is used to observe the change of the fluorescent indicator 2. In this embodiment, by providing the window 12 on the cavity 11, it is convenient to observe the fluorescence reaction of the fluorescent indicator 2 in the cavity 11 through the window 12. For example, the fluorescent indicator 2 will show different intensities of fluorescence under unheated and heated conditions, and it is convenient to observe the fluorescence phenomenon of the fluorescent indicator 2 in the cavity 11 through the window 12.

[0074] Optionally, the window 12 is a quartz window, a sapphire window, a magnesium aluminate spinel window, or an aluminum oxynitride window; the window 12 is bonded to the surface of the wafer 1. The window 12 in this embodiment is a quartz window, a sapphire window, a magnesium aluminate spinel window, or an aluminum oxynitride window, and has a long service life. The window 12 in this embodiment is bonded to the surface of the wafer 1, and the connection method between the window 12 and the wafer 1 is simple and convenient to manufacture.

[0075] Exemplarily, the window 12 is parallel to the surface of the wafer 1, the window 12 is higher than the surface of the wafer 1 or the window 12 is flush with the surface of the wafer 1. As Figure 4 shown, the position where the window 12 is located is higher than the plane of the wafer 1. The connection method between the window 12 and the wafer 1 in this structure is simpler than the connection method between the window 12 and the wafer 1 when the window 12 is flush with the surface of the wafer 1. AsFigure 5 As shown, the window 12 is flush with the surface of the wafer 1, keeping the surface of the wafer 1 still flat. When the surface of the window 12 is flush with the surface of the wafer 1, it is more convenient to adjust the overall weight to be the same as the weight of the original wafer 1.

[0076] In the above embodiment, the overall weight can be made the same as the weight of the original wafer 1 by adjusting the weight of the window 12. That is, the weight of the window 12 + the fluorescent indicator 2 + the wafer 1 is made the same as the weight of the original wafer 1 without the cavity 11 being opened, which is beneficial for the robot to transfer the wafer.

[0077] In a specific embodiment, the outer contour of the opening of the cavity 11 is circular, and the diameter of the outer contour of the opening of the cavity 11 is 1 - 10 mm; of course, in other embodiments, the outer contour of the opening of the cavity 11 can also be rectangular. When the outer contour of the opening of the cavity 11 is rectangular, the length or width of the outer contour of the opening of the cavity 11 is 1 - 10 mm. Technicians can preset the size of the cavity 11 according to the size of the wafer 1.

[0078] In the above embodiment, the filling thickness of the fluorescent indicator 2 inside the cavity 11 is 0.1 - 0.5 mm. The filling thickness of the fluorescent indicator 2 inside the cavity 11 has a certain value, which can ensure the accuracy of obtaining the temperature.

[0079] In the above embodiment, the temperature measurement structure 3 is a fluorescence optical fiber temperature measurement structure. The fluorescence optical fiber temperature measurement structure of this embodiment includes an optical fiber probe 31 and a temperature measurement display platform 32. Among them, one end of the optical fiber probe 31 is connected to the temperature measurement display platform 32, and the other end is used to obtain the optical signal of the fluorescent indicator 2. When the wafer surface temperature measurement device of this embodiment tests the CVD machine tool, only the wafer 1 provided with the fluorescent indicator 2 needs to be placed in the cavity of the CVD machine tool. After the wafer 1 is heated in the cavity of the CVD machine tool for a certain time, the wafer 1 is taken out from the cavity of the CVD machine tool. At room temperature, the fluorescence signal of the fluorescent indicator 2 at each cavity 11 on the wafer is obtained through the optical fiber probe 31. The temperature measurement display platform 32 can obtain the temperature of the fluorescent indicator 2 according to the fluorescence signal. According to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method described in the above embodiment, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator 2 on the wafer 1, the heating temperature and heating time of the fluorescent indicator 2 on the wafer are obtained, so as to obtain the heating temperature and heating time of the corresponding position on the surface of the wafer 1. The temperature measurement principle of the fluorescence optical fiber temperature measurement structure in this embodiment is prior art, and the temperature measurement principle of the fluorescence optical fiber temperature measurement structure in this embodiment will not be elaborated.

[0080] The wafer surface temperature measurement device provided by the embodiment of the present invention includes a wafer, a fluorescent indicator, and a temperature measurement structure. A plurality of cavities are formed on the surface of the wafer, and the cavities are arranged at intervals. The cavities are used to accommodate the fluorescent indicator. The temperature measurement structure is used to measure the temperature of the fluorescent indicator after heating the wafer, so as to obtain the heating temperature and heating time of the fluorescent indicator according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, thereby obtaining the heating temperature and heating time of the corresponding position on the wafer surface. This wafer surface temperature measurement device can simultaneously obtain the temperature on the wafer surface and the time when the wafer is heated, so as to obtain the true thermal power absorbed by the wafer surface. Moreover, it does not need to use an electronic temperature measurement chip and a wireless module, which improves the service life.

[0081] In the above description, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0082] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wafer surface temperature measurement method, characterized in that: include: calcining the fluorescent indicator at different preset temperatures, and calibrating the temperature of the fluorescent indicator after calcination at the same temperature for different time periods; Heating a wafer provided with the fluorescent indicator, wherein the fluorescent indicator is distributed at intervals at preset positions of the wafer; Obtaining the temperature of the fluorescent indicator on the wafer; The heating temperature and heating time of the fluorescent indicator are obtained according to the baking temperature of the fluorescent indicator, the temperature of the fluorescent indicator after baking in different time periods, and the temperature of the fluorescent indicator on the wafer, thereby obtaining the heating temperature and heating time of the corresponding position on the wafer surface.

2. The wafer surface temperature measurement method according to claim 1, characterized in that: In the method of baking the fluorescent indicator at different preset temperatures and calibrating the temperature of the fluorescent indicator after baking at the same temperature for different time periods, the different preset temperatures increase at preset temperature intervals, and the different time periods increase at preset time intervals.

3. The wafer surface temperature measurement method according to claim 2, characterized in that: The wafer provided with the fluorescent indicator is heated, wherein the fluorescent indicator is distributed at intervals on preset positions of the wafer, and the preset positions are a plurality of cavities opened on the surface of the wafer and arranged at intervals.

4. The wafer surface temperature measurement method according to claim 3, characterized in that: In the heating of the wafer provided with the indicator, the wafer is heated by a temperature equalizing plate, a heating plate or a constant temperature bath.

5. A wafer surface temperature measuring device, characterized in that: It includes a wafer, a fluorescent indicator and a temperature measurement structure; A plurality of cavities are provided on the surface of the wafer, the cavities are arranged at intervals, the cavities are used to accommodate the fluorescent indicator, and the temperature measuring structure is used to obtain the temperature of the fluorescent indicator after the wafer is heated, and the heating temperature and heating time of the fluorescent indicator are obtained according to the baking time of the fluorescent indicator calibrated in the wafer surface temperature measurement method according to any one of claims 1 to 4, the temperature of the fluorescent indicator after baking for different time periods, and the temperature of the fluorescent indicator on the wafer, thereby obtaining the heating temperature and heating time of the corresponding position on the wafer surface.

6. The wafer surface temperature measuring device according to claim 5, characterized in that: The cavity is a blind hole opened on the same surface of the wafer, and the blind holes are evenly arranged at intervals.

7. The wafer surface temperature measuring device according to claim 6, characterized in that: The cavities are distributed in an array on the surface of the wafer; or the cavities are evenly distributed along the center circumference of the wafer.

8. The wafer surface temperature measuring device according to claim 5, characterized in that: The fluorescent indicator is KLa(MoO4) 2+ 、Eu 3+ :La2O2S、Cr:YAG、Nd:Glass、Cr 3+ :LiSrAlF6, Cr:Al2O3, Nd:YAG or Cr:BeAl2O3; or the fluorescent indicator is doped with Nd 3+ Fluorescent materials, doped with Tm 3+ Fluorescent materials, doped with Er 3+ Fluorescent materials or Cr-doped 3+ of fluorescent materials.

9. The wafer surface temperature measuring device according to claim 5, characterized in that: The cavity is provided with a window, and the window is used to observe the change of the fluorescent indicator.

10. The wafer surface temperature measuring device according to claim 9, characterized in that: The window is a quartz window, a sapphire window, a magnesium aluminum spinel window or an aluminum nitride oxide window; and the window is bonded to the surface of the wafer.

11. The wafer surface temperature measuring device according to claim 9, characterized in that: The viewing window is parallel to the surface of the wafer, the viewing window is higher than the surface of the wafer, or the viewing window is flush with the surface of the wafer.

12. The wafer surface temperature measuring device according to any one of claims 5 to 11, characterized in that: The outer contour of the cavity opening is circular, and the diameter of the circle is 1-10 mm; Alternatively, the outer contour of the cavity opening is a rectangle, and the length or width of the rectangle is 1-10 mm; The filling thickness of the fluorescent indicator inside the cavity is 0.1-0.5 mm.

13. The wafer surface temperature measuring device according to any one of claims 5 to 11, characterized in that: The temperature measurement structure is a fluorescent optical fiber temperature measurement structure, which includes an optical fiber probe and a temperature measurement display platform. One end of the optical fiber probe is connected to the temperature measurement display platform, and the other end of the optical fiber probe is used to obtain the light signal of the fluorescent indicator.

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