System for measuring thickness of thin film in real time by using acoustic wave element

Abstract

The invention provides a system for instantly measuring the thickness of a film by using an acoustic wave element, which comprises at least one carrier with a film with a film thickness; the at least one sound wave unit is arranged on the peripheral side of the carrier and detects the change of the thickness of the film in real time so as to generate a resonant frequency; a calculation unit receives and processes the resonant frequency generated by the detection of the acoustic wave element. The calculation unit calculates at least one film thickness frequency two-dimensional coordinate system before correction according to the film thickness and the resonant frequency, and calculates at least one temperature frequency compensation two-dimensional coordinate system according to the cavity temperature and the resonant frequency; and the calculation unit calculates the film thickness frequency two-dimensional coordinate system before correction and the temperature frequency compensation two-dimensional coordinate system to obtain a film thickness measurement three-dimensional coordinate system for interpolation search during measurement to obtain the film thickness, so that the film thickness can be detected and fed back in real time, the accuracy is high, and the coating yield is improved.

Description

Technical Field

[0001] This invention relates to thin film thickness measurement, and in particular to a system for real-time measurement of thin film thickness using acoustic wave elements. Background Technology

[0002] When coating on a wafer carrier, for example, various operating parameters need to be adjusted based on the coating thickness, and the coating thickness is also used for calculating other data. Currently, commonly used acoustic wave elements for coating thickness measurement include Surface Acoustic Wave (SAW), Film Bulk Acoustic Resonator (FBAR), and Bulk Acoustic Waves-Solidly Mounted Resonator (BAW-SMR), which use the detected resonant frequency to calculate the coating thickness. However, as the coating thickness increases, or the cavity temperature rises during coating, the detected resonant frequency is affected, resulting in a significant deviation between the coating thickness calculated using this resonant frequency and the actual coating thickness. To avoid the cavity temperature affecting the accuracy of the measured resonant frequency, manufacturers only measure the film thickness and collect resonant frequency data after the wafer carrier and acoustic wave components have cooled down after the coating is completed. However, offline measurement requires repeated measurements in a vacuum state after the cavity is evacuated and then evacuated again. In addition to the extra time consumption, it is also impossible to know the changes in the coating thickness during the coating process in real time so as to make corresponding adjustments immediately. Furthermore, after stopping and restarting the coating, there is a connection error between the old and new film layers, which leads to a decrease in coating yield and the problem of scrapping and starting over.

[0003] Furthermore, some existing technologies employ a temperature compensation layer (e.g., SiO2) on the acoustic wave element to compensate for temperature changes during coating. However, this method only reduces the interference of temperature on the resonant frequency and still cannot continuously monitor changes in coating thickness during the coating process. Moreover, these conventional technologies only consider the effect of temperature changes on the resonant frequency, without incorporating the resonant frequency change caused by increased coating thickness into the variable comparison to calculate an accurate coating thickness. Therefore, conventional technologies neither possess the ability to monitor coating thickness changes in real time nor provide a precise resonant frequency for calculating an accurate coating thickness.

[0004] Therefore, how to solve the above problems is the primary issue that this invention aims to address. Summary of the Invention

[0005] The main objective of this invention is to provide a system for real-time measurement of thin film thickness using acoustic wave elements. This system utilizes a two-dimensional coordinate system for film thickness measurement, consisting of a pre-correction film thickness frequency coordinate system (composed of film thickness and resonant frequency) and a temperature-frequency compensated two-dimensional coordinate system (composed of temperature and resonant frequency). This forms a three-dimensional coordinate system for film thickness measurement that includes the corresponding values ​​of cavity temperature, film thickness, and resonant frequency. By interpolating the real-time measured cavity temperature and resonant frequency within this three-dimensional coordinate system, a three-dimensional coordinate system of (cavity temperature - resonant frequency - film thickness) can be obtained, thus providing real-time film thickness measurement. This system not only allows for real-time detection of film thickness changes to adjust operating parameters but also enables rapid acquisition of film thickness-related values, shortening the measurement time.

[0006] To achieve the aforementioned objectives, the present invention provides a system for real-time measurement of thin film thickness using an acoustic wave element, the system comprising:

[0007] At least one carrier has a thin film deposited on its surface, the thin film having a film thickness;

[0008] At least one acoustic element is disposed on the periphery of the carrier to detect changes in the film thickness in real time and generate a resonant frequency;

[0009] A computing unit is used to receive and process the resonant frequency detected by the acoustic wave element;

[0010] When a thin film is continuously deposited on the surface of the carrier, the surface of the acoustic element is also deposited with the same thin film to detect the change in film thickness in real time. The resonant frequency generated by the acoustic element decreases as the film thickness increases. Under fixed temperature conditions, the calculation unit generates at least one pre-corrected film thickness frequency two-dimensional coordinate system based on the measured values ​​of film thickness and resonant frequency. The X-axis of the pre-corrected film thickness frequency two-dimensional coordinate system is the film thickness, and the Y-axis is the resonant frequency.

[0011] As the cavity temperature continues to rise, the temperature of the acoustic element also rises. The acoustic element detects the resonant frequency generated by the film thickness in real time, which decreases as the temperature increases. Under the condition of fixed film thickness, the calculation unit generates at least one temperature frequency compensation two-dimensional coordinate system corresponding to the measured values ​​of cavity temperature and resonant frequency. The X-axis of the temperature frequency compensation two-dimensional coordinate system is the cavity temperature, and the Y-axis is the resonant frequency.

[0012] The calculation unit further integrates the pre-correction film thickness frequency two-dimensional coordinate system and the temperature frequency compensation two-dimensional coordinate system to generate a film thickness measurement three-dimensional coordinate system. The X-axis of the film thickness measurement three-dimensional coordinate system is the cavity temperature, the Y-axis is the film thickness, and the Z-axis is the resonant frequency. A three-dimensional coordinate system containing the corresponding values ​​of cavity temperature, film thickness, and resonant frequency can be obtained. When the acoustic wave element detects the film thickness, the detected resonant frequency value and cavity temperature can be interpolated and searched in the film thickness measurement three-dimensional coordinate system to obtain a three-dimensional coordinate value containing cavity temperature, film thickness, and resonant frequency. The corresponding film thickness can then be obtained. The film thickness can be measured in real time by intermittently measuring the cavity temperature and resonant frequency during the coating process.

[0013] Preferably, the resonant frequency of the acoustic element is between

[0014] Preferably, when the acoustic wave element detects the change in the film thickness of the carrier in real time, the resonant frequency of the acoustic wave element changes by approximately 1 nm for every 1 nm increase in film thickness.

[0015] Preferably, this system is suitable for temperature variations ranging from [temperature range missing]. The thickness range of the deposited film is: The carrier coating environment.

[0016] Preferably, the carriers face a coating source, and a plurality of baffles are provided between the coating source and the carriers. The baffles communicate with the computing unit and control the relative position between the baffles and the carriers according to the film thickness detected by the computing unit in real time, so as to adjust the uniformity of the coating of the carriers by the coating source.

[0017] Preferably, when the coating process of these carriers is completed and the etching operation is started, these acoustic elements also work with the computing unit to measure the film thickness in real time in order to adjust the film etching depth.

[0018] Preferably, several acoustic wave elements are arranged in an array around each carrier, and each acoustic wave element is provided with a corresponding MEMS (Micro Electro Mechanical Systems) switch element, so that these MEMS switch elements are arranged in an array, and the operation or shutdown of the corresponding acoustic wave element is determined by turning these MEMS switches on and off.

[0019] Preferably, each carrier is placed in a deposition area, or the deposition area is arranged close to the periphery of the carrier. The surface area of ​​each MEMS switching element on the side corresponding to the acoustic element is larger than the effective resonant area of ​​the acoustic element, so as to completely block the effective resonant area of ​​the acoustic element and thus control the operation of the acoustic element.

[0020] Preferably, the above-described system for real-time measurement of film thickness includes the following operational steps during carrier coating:

[0021] In step one, each acoustic element is placed at a different distance from a coating source to collect resonant frequencies under different environmental conditions.

[0022] Step 2: The calculation unit receives the resonant frequency and calculates a film thickness deposition rate by operating the system that measures the film thickness in real time, and then sends the film thickness deposition rate data back to a control system.

[0023] Step 3: The control system adjusts the blocking area, blocking angle and blocking distance of each baffle to the source of the coating.

[0024] Step 4: Repeat Step 2 and determine whether the target film thickness deposition rate has been reached. If not, repeat Step 3; if it has been reached, proceed to Step 5.

[0025] Step 5: Fix the parameters of the baffle.

[0026] Preferably, in step one, the cavity is heated before coating and the resonant frequency generated by the acoustic wave element is tested. The coating measurement is performed after the resonant frequency is determined to be within a calibration range. During the coating measurement, the change of the resonant frequency is detected and compared with whether it exceeds the calibration range of the resonant frequency to determine whether the acoustic wave element can operate normally.

[0027] The above-mentioned objects and advantages of the present invention can be readily understood from the following detailed description and accompanying drawings of the selected embodiments. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a two-dimensional coordinate system diagram of the film thickness frequency before correction according to the present invention.

[0030] Figure 2 This is a two-dimensional coordinate curve of thin film thickness-resonance frequency for acoustic wave elements with different resonant areas under 25°C conditions according to the present invention.

[0031] Figure 3 This is a two-dimensional coordinate system diagram for temperature frequency compensation according to the present invention.

[0032] Figure 4 This is a two-dimensional coordinate system diagram of the temperature and frequency compensation of the acoustic wave element with different coating thicknesses according to the present invention.

[0033] Figure 5 This is a three-dimensional coordinate system diagram for film thickness measurement according to the present invention.

[0034] Figure 6 This is a two-dimensional coordinate curve of the resonant area-resonant frequency of the acoustic wave element with different film thicknesses under 25℃ conditions according to the present invention.

[0035] Figure 7 This is a two-dimensional coordinate curve of the resonant area-resonant frequency of the acoustic wave element with different film thicknesses under 40℃ conditions according to the present invention.

[0036] Figure 8 This is a schematic diagram showing the position and structure of the acoustic wave element and the MEMS switching element of the present invention.

[0037] Figure 9 This is a schematic diagram showing the location and structure of the coating source and carrier in this invention.

[0038] Figure 10 This is a block diagram illustrating the connection relationships between the various components of the present invention.

[0039] Figure 11 This is a schematic diagram of the film thickness monitoring and correction process of the present invention.

[0040] Among them, the acoustic wave element 1; the carrier 2; the MEMS switching element 3; the coating source 4; and the baffle 5. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] like Figures 1 to 11 As shown, this is a system for real-time measurement of thin film thickness using an acoustic wave element provided by an embodiment of the present invention. The system includes at least one carrier, at least one acoustic wave element, and a computing unit.

[0043] Please see Figure 9 As shown, this embodiment includes three carriers, each with an acoustic wave element on its periphery. This element is used to detect in real-time changes in the film thickness formed on the carrier surface during coating and to generate a resonant frequency. The resonant frequency of this acoustic wave element is between [insert frequency here]. The acoustic wave element is one of Surface Acoustic Wave (SAW), FilmBulk Acoustic Resonator (FBAR), or Bulk Acoustic Waves-Solidly Mounted Resonator (BAW-SMR). All of these acoustic wave elements change frequency with temperature. The acoustic wave element in this embodiment is FBAR.

[0044] Continuing from the above, as a thin film is continuously deposited on the surface of the carrier, the surface of the acoustic wave element is also coated with the same thin film to detect changes in the film thickness in real time. The resonant frequency generated by the acoustic wave element decreases as the film thickness increases. It should be specifically noted that for every 1 nm increase in film thickness, the resonant frequency of the acoustic wave element changes by approximately [missing information]. Under fixed temperature conditions, the calculation unit generates a value corresponding to the [thin film thickness - resonant frequency] measurement. Figure 1 The diagram shows a two-dimensional coordinate system for the pre-correction film thickness frequency. Under stable cavity temperatures of 25°C, 40°C, 50°C, and 100°C, the invention measures the change in resonant frequency with increasing film thickness. The calculation unit detects the measured values, including film thickness and resonant frequency, generated by different film thicknesses under four different temperature conditions, thus obtaining the corresponding two-dimensional coordinate system for the pre-correction film thickness frequency, where the X-axis represents film thickness and the Y-axis represents resonant frequency.

[0045] Please see Figure 2 The curves shown represent the relationship between film thickness and resonant frequency for acoustic wave elements with different resonant areas at a cavity temperature of 25°C. The resonant areas of the acoustic wave elements are 6400 μm... 2 10000μm 2 14400μm 2 and 25600μm 2 Under conditions where the film thickness is 0 nm (i.e., uncoated), 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, and 50 nm, the resonant frequency detected by the acoustic wave element gradually decreases with increasing film thickness. As can be seen from the above two-dimensional coordinate system of film thickness and frequency before correction, under the condition of constant cavity temperature, as the film thickness of the carrier increases, the resonant frequency detected by the acoustic wave element gradually decreases.

[0046] As the cavity temperature continues to rise, the temperature of the acoustic wave element also increases. The acoustic wave element, by detecting the thin film thickness in real time, determines that the resonant frequency decreases with increasing temperature. Under a fixed thin film thickness, the calculation unit generates a corresponding value based on the measured values ​​including the cavity temperature and resonant frequency. Figure 3The temperature-frequency compensation two-dimensional coordinate system shown has the cavity temperature on the X-axis and the resonant frequency on the Y-axis. Furthermore, when the effective resonant area of ​​the acoustic wave element is 6400 μm... 2 This invention measures and records the change in resonant frequency as the temperature increases when the carrier and acoustic element have different film thicknesses of 0nm (uncoated), 5nm, 10nm, 15nm, 30nm, and 50nm, and cavity temperatures of 25℃, 40℃, 50℃, and 100℃. The calculation unit detects the measured values ​​including cavity temperature and resonant frequency generated under the four different temperature conditions corresponding to different film thicknesses, and then obtains the corresponding temperature-frequency compensation two-dimensional coordinate system. The pre-correction temperature-frequency compensation two-dimensional coordinate system is then compiled as follows: Figure 4 As shown in the above temperature frequency compensation two-dimensional coordinate system, under the condition that the thickness of the carrier film remains unchanged, the cavity temperature gradually increases, while the resonant frequency detected by the acoustic wave unit gradually decreases.

[0047] Next, the calculation unit further integrates and calculates these uncorrected film thickness frequency two-dimensional coordinate systems and these temperature frequency compensation coordinate systems to generate a result as follows: Figure 5 The illustrated three-dimensional coordinate system for film thickness measurement has the X-axis representing cavity temperature, the Y-axis representing film thickness, and the Z-axis representing resonant frequency. This system provides a three-dimensional coordinate system containing the corresponding values ​​of cavity temperature, film thickness, and resonant frequency. When the acoustic wave element detects the film thickness, the detected resonant frequency and cavity temperature can be interpolated within this three-dimensional coordinate system to obtain a three-dimensional coordinate value of [cavity temperature - film thickness - resonant frequency]. This yields the corresponding film thickness. By intermittently measuring the cavity temperature and resonant frequency during the coating process, the system achieves real-time measurement of film thickness. This system is suitable for temperature variations ranging from [specific temperature range to a specified value]. The thickness range of the deposited film is: The carrier coating environment.

[0048] Among them, such as Figure 9 and Figure 10As shown, the carriers 2 face a coating source 4, which sputters a coating material onto the surface of the carriers 2 to form a thin film. The coating method can be vapor deposition, sputtering, or chemical vapor deposition. A plurality of baffles 5 are provided between the coating source 4 and the carriers 2. In this embodiment, three carriers 2 face one coating source 4, and at least two baffles 5 that can swing left and right are provided between the coating source 4 and the carriers 2. These baffles 5 communicate with the computing unit, which obtains the real-time thin film thickness in the three-dimensional coordinate system of the film thickness measurement based on the real-time detected cavity temperature and resonant frequency. The computing unit controls and changes the relative position between the baffles 5 and the carriers 2 according to the real-time thin film thickness to adjust the uniformity of the coating applied to the carriers by the coating source. In detail, the baffle 5 is used to adjust the coating rate of the coating source. The area of ​​the baffle 5 blocking the coating source 4 or the carrier 2 is inversely proportional to the film thickness. When the film thickness is thicker, it is closer to the target set thickness. At this time, the coating rate should be slowed down. Therefore, the calculation unit controls the baffle 5 to move to increase the blocking area, adjust the blocking angle and blocking distance, thereby reducing the coating rate and ensuring the uniformity of the coating on the carrier.

[0049] like Figure 8 As further illustrated, the present invention arranges several acoustic wave elements 1 in an array around each carrier 2, and each acoustic wave element 1 is correspondingly provided with a MEMS (Micro Electro Mechanical Systems) switch element 3, so that these MEMS switch elements 3 form an array arrangement. Further, each carrier is correspondingly placed in a deposition area; in other feasible embodiments, the deposition area can also be arranged close to the carrier. The surface area of ​​each MEMS switch element on the side corresponding to the acoustic wave element is larger than the effective resonant area of ​​the acoustic wave element, so as to completely shield the acoustic wave element 1. By turning the MEMS switches 3 on and off, the operation or shutdown of the corresponding acoustic wave element 1 is determined; that is, when the MEMS switch 3 is on, the corresponding acoustic wave element 1 operates and generates a resonant frequency; when the MEMS switch 3 is closed, the corresponding acoustic wave element 1 is off and stops operating, realizing flexible adjustment of the operating acoustic wave elements according to the number of carriers to be measured. During thin film thickness measurement, at least one acoustic element is activated as part of the measurement group to monitor changes in the film thickness of the carrier. Another acoustic element can be activated at different coating times and temperatures as a control group. The resonant frequency detected by the control group is compared with the data from the measurement group to determine if there are any issues with the resonant frequency detected by the measurement group. Alternatively, after a period of use, such as 1000 hours, the control group can be activated to verify the accuracy of the acoustic elements.

[0050] in addition, Figure 2 , Figure 6 and Figure 7The curve shown represents the relationship between the resonant area of ​​the acoustic wave element, the SiO2 film thickness, and the resonant frequency. This is achieved at cavity temperatures of 25℃ and 40℃, and film thicknesses of 0nm (uncoated), 5nm (nanometers), 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, and 50nm, with an effective resonant area of ​​6400μm. 2 (square micrometers, μm) 2 ), 10000μm 2 14400μm 2 25600μm 2 Under certain conditions, the resonant frequency detected by the acoustic wave element increases with the increase of the effective resonant area of ​​the acoustic wave element, but decreases with the increase of the film thickness. Based on this, the real-time thin film thickness measurement system can be finely adjusted by partially opening or closing the MEMS switch, and it can also be used to correct resonant frequency drift caused by temperature rise.

[0051] like Figure 11 As shown, the system of the present invention for real-time measurement of thin film thickness using acoustic wave elements includes the following operational steps during carrier coating:

[0052] Step 1: Each acoustic element is placed at a different distance from a coating source to collect resonant frequencies under different environmental conditions (such as cavity temperature). Before coating, the cavity is heated and the resonant frequency generated by the acoustic element is tested. The coating measurement is performed after the resonant frequency is determined to be within a calibration range. During the coating measurement, the change of the resonant frequency is detected and compared with whether it exceeds the calibration range to determine whether the acoustic element is operating normally. Step 2 is then executed after the normal operation is determined.

[0053] Step 2: The calculation unit receives the resonant frequency and calculates a film thickness deposition rate by operating the system that measures the film thickness in real time, and then sends the film thickness deposition rate data back to a control system.

[0054] Step 3: The control system adjusts the blocking area, blocking angle and blocking distance of each baffle to the source of the coating.

[0055] Step 4: Repeat Step 2 and determine whether the target film thickness deposition rate has been reached. If not, repeat Step 3; if it has been reached, proceed to Step 5.

[0056] Step 5: Fix the parameters of the baffle.

[0057] This invention can also be applied to etching operations after coating is completed. It utilizes the principle that the resonant frequency decreases as the film thickness increases during coating, and increases as the film thickness decreases during etching, while the frequency decreases as the cavity temperature rises. After the coating process of these carriers is completed, when the etching operation begins, these acoustic wave elements, in conjunction with the calculation unit, measure the film thickness in real time. The calculation unit obtains the film etching depth based on the increase in resonant frequency, and then adjusts the film etching depth according to process requirements.

[0058] As can be seen from the above embodiments, the system for real-time measurement of thin film thickness using acoustic wave elements provided by the present invention can achieve the following improvements:

[0059] First, real-time detection and feedback of film thickness improves coating yield. This invention constructs a three-dimensional coordinate system for film thickness calculation that includes cavity temperature, film thickness, and resonant frequency. In actual use, only the cavity temperature and resonant frequency need to be detected, and the above two data are interpolated and searched within the three-dimensional coordinate system for film thickness calculation to obtain an accurate film thickness. The calculation efficiency is high, and the real-time feedback of the key parameter film thickness in the process is beneficial for operators to adjust the operating parameters in a timely manner, ensuring the uniformity of coating and improving the coating yield.

[0060] Secondly, the automatic compensation for resonant frequency changes caused by cavity temperature results in high accuracy. Conventional techniques use temperature compensation layers to compensate for temperature changes in the cavity during coating, but because these layers cannot be flexibly adjusted according to actual production conditions, their compensation for temperature changes is inaccurate. This invention, however, establishes a three-dimensional coordinate system for film thickness calculation based on extensive experimental data, encompassing resonant frequencies corresponding to different cavity temperature conditions. This resonant frequency is used to compensate for the actually measured resonant frequency within the film thickness calculation three-dimensional coordinate system, thereby obtaining an accurate film thickness.

[0061] Third, the acoustic wave elements can be flexibly selected; compared with conventional technology, the present invention does not require the addition of a temperature compensation layer to the acoustic wave elements before the film thickness of the carrier coating can be detected, so most acoustic wave elements are suitable for the present invention.

[0062] Fourth, it can be applied to film thickness detection in different processes; this invention can be applied to real-time film thickness detection during coating and etching. After the coating process is completed, it can immediately switch to etching. The acoustic element of this invention also works with the calculation unit to detect the film thickness in real time. It utilizes the principle that the resonant frequency decreases when the film thickness increases during coating, and the resonant frequency increases when the film thickness decreases during etching, and the frequency decreases when the cavity temperature rises. The calculation unit obtains the film etching depth based on the increase in resonant frequency, and then adjusts the film etching depth according to process requirements.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for real-time measurement of thin film thickness using acoustic wave elements, characterized in that, The system comprises: at least one carrier, a surface of which is plated with a thin film, the thin film having a film thickness; at least one acoustic wave element arranged on the periphery of the carrier to detect the change in the film thickness in real time and generate a resonance frequency; a computing unit for receiving and processing the resonance frequency detected by the acoustic wave element; when the surface of the carrier is continuously plated with the thin film, the surface of the acoustic wave element is also plated with the same thin film to detect the change in the film thickness in real time, the resonance frequency generated by the acoustic wave element decreases with the increase of the film thickness, and under the condition of a fixed temperature, at least one pre-correction film thickness-frequency two-dimensional coordinate system is generated by the computing unit through the measured values of the film thickness and the resonance frequency, wherein the X-axis of the pre-correction film thickness-frequency two-dimensional coordinate system is the film thickness, and the Y-axis is the resonance frequency; when the temperature of the cavity continuously rises, the temperature of the acoustic wave element rises, the resonance frequency generated by the acoustic wave element in real time detecting the film thickness decreases with the increase of the temperature, and under the condition of a fixed film thickness, at least one temperature-frequency compensation two-dimensional coordinate system is generated by the computing unit through the measured values of the cavity temperature and the resonance frequency, wherein the X-axis of the temperature-frequency compensation two-dimensional coordinate system is the cavity temperature, and the Y-axis is the resonance frequency; the computing unit further integrates the pre-correction film thickness-frequency two-dimensional coordinate system and the temperature-frequency compensation two-dimensional coordinate system to generate a film thickness measurement three-dimensional coordinate system, the X-axis of the film thickness measurement three-dimensional coordinate system is the cavity temperature, the Y-axis is the film thickness, and the Z-axis is the resonance frequency, a three-dimensional coordinate containing the corresponding values of the cavity temperature, the film thickness and the resonance frequency can be obtained, so that when the acoustic wave element detects the film thickness, the detected resonance frequency value, the cavity temperature and the film thickness measurement three-dimensional coordinate system can be interpolated and searched to obtain a three-dimensional coordinate value containing the cavity temperature, the film thickness and the resonance frequency, and the corresponding film thickness can be obtained, and the cavity temperature and the resonance frequency are measured intermittently in the plating process to achieve the function of measuring the film thickness in real time.

2. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 1, wherein The resonant frequency of the acoustic wave element is between 3. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 1, wherein When the acoustic wave element detects the change in the film thickness of the carrier in real time, the resonance frequency of the acoustic wave element changes between 0.1 kHz and 1 kHz per 1 nm of increase in the film thickness 4. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 1, wherein The system is suitable for a temperature change range of The thickness of the plated film ranges from The carrier plating environment.

5. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 1, wherein The carriers face a plating source, a plurality of baffles are arranged between the plating source and the carriers, the baffles communicate with the computing unit, and the relative positions between the baffles and the carriers are controlled to adjust the uniformity of the plating of the carriers by the plating source according to the film thickness detected by the computing unit in real time.

6. The system for measuring film thickness in real time using acoustic wave elements according to claim 1, wherein When the plating process of the carriers is completed and etching is performed, the acoustic wave elements also detect the film thickness in real time to adjust the etching depth of the film in cooperation with the computing unit.

7. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 1, wherein A plurality of acoustic wave elements are arranged in an array on the periphery of each carrier, and each acoustic wave element is correspondingly provided with a MEMS switch element, so that the MEMS switch elements form an array, and the operation or shutdown of the corresponding acoustic wave element is determined by opening and closing the MEMS switch.

8. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 7, wherein Each carrier is correspondingly placed in a deposition area, or the deposition area is arranged close to the periphery of the carrier, the surface area of one side of each MEMS switch element corresponding to the acoustic wave element is greater than the resonance effective area of the acoustic wave element, so as to completely shield the resonance effective area of the acoustic wave element and control the operation of the acoustic wave element.

9. The system for measuring the thickness of a thin film in real time using acoustic waves according to any one of claims 1 to 8, wherein The system for instant measurement of film thickness comprises the following operation steps when coating a carrier: Step one, each acoustic wave element is also arranged at different distances from a coating source to collect resonance frequencies under different environmental conditions; Step two, the calculation unit receives the resonance frequencies and calculates a film thickness deposition rate by operating the system for instant measurement of film thickness, and returns the data of the film thickness deposition rate to a control system; Step three, the control system adjusts the blocking area, angle and distance of each baffle to the coating source; Step four, repeat step two and determine whether the target film thickness deposition rate is reached, if not, repeat step three, if reached, execute step five; Step five, fix the parameters of the baffle.

10. The system for measuring the thickness of a thin film in real time using an acoustic wave element according to claim 9, wherein In step one, the cavity is heated before coating and the resonance frequency generated by the acoustic wave element is tested, and after determining that the resonance frequency is within a corrected range, coating measurement is performed. During the coating measurement process, the change of the resonance frequency is detected and compared with whether it exceeds the corrected resonance frequency range to determine whether the acoustic wave element can normally operate.

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