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

Abstract

A system for measuring a thin-film thickness in real time by using an acoustic wave element (1). The system comprises: at least one carrier (2), which has a thin film, wherein the thin film has a thin-film thickness; at least one acoustic wave unit (1), which is disposed around the carrier (2), and detects a change in the thin-film thickness in real time, so as to generate a resonant frequency; and a calculation unit, which receives and processes the resonant frequency, which is generated by the acoustic wave element (1) via detection. The calculation unit obtains at least one pre-correction two-dimensional film thickness frequency coordinate system on the basis of the value of the thin-film thickness and the value of the resonant frequency, and further obtains at least one two-dimensional temperature-frequency compensation coordinate system on the basis of the value of a cavity temperature and the value of the resonant frequency. The calculation unit then performs operations on the pre-correction two-dimensional film thickness frequency coordinate system and the two-dimensional temperature-frequency compensation coordinate system, so as to obtain a three-dimensional film thickness measurement coordinate system for performing an interpolation search during measurement, thereby obtaining a thin-film thickness. A thin-film thickness can be measured and fed back in real time, and the accuracy is high, thereby improving the coating yield.

Description

System for measuring film thickness in real time using acoustic wave element TECHNICAL FIELD

[0001] The present invention relates to film thickness measurement, and in particular to a system for measuring film thickness in real time using acoustic wave element. BACKGROUND

[0002] When coating on a wafer carrier, the thickness of the coating needs to be measured to adjust various operation parameters, and the thickness of the coating is also used for calculating other data. The acoustic wave elements commonly used for measuring the thickness of the coating include Surface Acoustic Wave (SAW), Film Bulk Acoustic Resonator (FBAR), Bulk Acoustic Waves-Solidly Mounted Resonator (BAW-SMR), etc. The thickness of the coating is calculated by detecting the resonant frequency. However, as the thickness of the coating increases, or the temperature of the cavity increases during coating, the resonant frequency detected is affected, resulting in a large deviation between the coating thickness calculated by the resonant frequency and the actual coating thickness. To avoid the influence of the temperature of the cavity on the accuracy of the measured resonant frequency, the manufacturer only measures the film thickness and collects resonant frequency data after the wafer carrier and the acoustic wave element are cooled after coating is completed. However, off-line measurement must be performed repeatedly in a state where the cavity is broken and then vacuumized, which not only consumes additional time, but also cannot obtain the change of the coating thickness in real time during the coating process to immediately adjust the operation, and there is a connection error between the new and old film layers after the coating is stopped and restarted, resulting in a decrease in the yield of the coating and the problem of scrapping and reworking.

[0003] In addition, some existing technologies use a temperature compensation layer (such as SiO2) in the acoustic wave element to compensate for the temperature change of the acoustic wave element during coating, but this method can only reduce the interference of temperature on the resonant frequency, and still cannot continuously and uninterruptedly detect the change of the coating thickness during the coating process. Moreover, such conventional technologies only consider the influence of temperature change on the resonant frequency, and do not jointly consider the change of the resonant frequency caused by the increase of the coating thickness to calculate the accurate coating thickness. Therefore, the conventional technologies neither have the function of real-time monitoring the change of the coating thickness, nor can provide an accurate resonant frequency to calculate the accurate coating thickness.

[0004] Therefore, how to solve the above problems is the primary object of the present invention. SUMMARY

[0005] The main object of the present application is to provide a system for real-time measurement of film thickness by using acoustic wave elements. The system comprises a film thickness measurement three-dimensional coordinate system including cavity temperature, film thickness and resonance frequency corresponding values. The cavity temperature and resonance frequency obtained by real-time measurement are inserted and searched in the film thickness measurement three-dimensional coordinate system, so that a three-dimensional coordinate of (cavity temperature-resonance frequency-film thickness) is obtained, thereby obtaining the film thickness in real time. The system can not only detect the film thickness change in real time to adjust the operation parameters, but also quickly obtain the film thickness related values, thereby shortening the measurement time.

[0006] To achieve the above-mentioned object, the present application provides a system for real-time measurement of film thickness by using acoustic wave elements. The system comprises:

[0007] At least one carrier having a film plated on the surface thereof, the film having a film thickness;

[0008] At least one acoustic wave element arranged on the side of the carrier to detect the change of the film thickness in real time and generate a resonance frequency;

[0009] A computing unit for receiving and processing the resonance frequency detected by the acoustic wave element;

[0010] When the film is continuously plated on the surface of the carrier, the surface of the acoustic wave element is also plated with the same film to detect the change of the film thickness in real time. The resonance frequency generated by the acoustic wave element decreases with the increase of the film thickness. Under the condition of fixed temperature, at least one pre-correction film thickness frequency two-dimensional coordinate system is generated by the computing unit corresponding to the measured values of the film thickness and the resonance frequency. In the pre-correction film thickness frequency two-dimensional coordinate system, the X-axis is the film thickness and the Y-axis is the resonance frequency.

[0011] When the cavity temperature continuously rises, the temperature of the acoustic wave element rises. The resonance frequency generated by the acoustic wave element detecting the film thickness decreases with the increase of the temperature. Under the condition of fixed film thickness, at least one temperature frequency compensation two-dimensional coordinate system is generated by the computing unit corresponding to the measured values of the cavity temperature and the resonance frequency. In the temperature frequency compensation two-dimensional coordinate system, the X-axis is the cavity temperature and the Y-axis is the resonance frequency.

[0012] 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, so that 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 are interpolated and searched to obtain a three-dimensional coordinate value containing the cavity temperature, the film thickness, and the resonance frequency, so that the corresponding film thickness can be obtained, and the cavity temperature and the resonance frequency are intermittently measured during the film deposition process to achieve the effect of real-time measurement of the film thickness.

[0013] Preferably, the resonance frequency of the acoustic wave element is between 100 MHz and 1000 MHz.

[0014] Preferably, 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 MHz / nm and 10 MHz / nm when the film thickness increases by 1 nm.

[0015] Preferably, the system is suitable for a temperature change range of 0°C to 100°C. Preferably, the film thickness range of the deposited film is 0 nm to 1000 nm. Preferably, the system is suitable for a film deposition environment of the carrier.

[0016] Preferably, the carriers face a film deposition source, and a plurality of baffles are arranged between the film deposition source and the carriers. The baffles are in communication with the computing unit, and the relative positions between the baffles and the carriers are controlled to adjust the uniformity of the film deposition on the carriers according to the film thickness detected by the computing unit in real time.

[0017] Preferably, when the film deposition process of the carriers is completed and etching is performed, the acoustic wave elements also cooperate with the computing unit to measure the film thickness in real time to adjust the film etching depth.

[0018] Preferably, a plurality of acoustic wave elements are arranged in an array on the periphery of each carrier, and each acoustic wave element is provided with a MEMS (Micro Electro Mechanical Systems) 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.

[0019] Preferably, each carrier is placed in a deposition area or arranged close to the periphery of the carrier, and the surface area of each MEMS switch element on one side of 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.

[0020] Preferably, the system for instant measuring film thickness comprises the following steps when coating the carrier:

[0021] Step 1, each acoustic wave element is also arranged at different distances from a coating source to collect resonance frequencies under different environmental conditions;

[0022] Step 2, the calculation unit receives the resonance frequencies and calculates a film thickness deposition rate by operating the system for instant measuring film thickness, and returns the data of the film thickness deposition rate to a control system;

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

[0024] Step 4, repeat step 2 and determine whether the target film thickness deposition rate is reached, if not, repeat step 3, if reached, perform step 5;

[0025] Step 5, fix the parameters of the baffle.

[0026] Preferably, in step 1, 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 operate normally.

[0027] The above-mentioned objects and advantages of the present application can be clearly understood from the following detailed description of the selected embodiments and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0029] Fig. 1 is a two-dimensional coordinate system diagram of film thickness frequency before correction of the present application.

[0030] Fig. 2 is a film thickness-resonance frequency two-dimensional coordinate curve diagram of acoustic wave elements with different resonance areas under the condition of 25℃ of the present application.

[0031] Fig. 3 is a temperature frequency compensation two-dimensional coordinate system diagram of the present application.

[0032] Fig. 4 is a temperature frequency compensation two-dimensional coordinate system diagram of acoustic wave elements with different coating thicknesses of the present application.

[0033] Fig. 5 is a three-dimensional coordinate system diagram of film thickness measurement of the present application.

[0034] Figure 6 is a resonance area-resonance frequency two-dimensional coordinate graph of the acoustic wave element of the present application with different film thicknesses at 25°C.

[0035] Figure 7 is a resonance area-resonance frequency two-dimensional coordinate graph of the acoustic wave element of the present application with different film thicknesses at 40°C.

[0036] Figure 8 is a schematic diagram of the position structure of the acoustic wave element and the MEMS switch element of the present application.

[0037] Figure 9 is a schematic diagram of the position structure of the film plating source and the carrier of the present application.

[0038] Figure 10 is a block schematic diagram of the connection relationship of the components of the present application.

[0039] Figure 11 is a flowchart of the film thickness monitoring and correction of the present application.

[0040] Among them, the acoustic wave element 1; the carrier 2; the MEMS switch element 3; the film plating source 4; the baffle 5. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0042] As shown in Figures 1 to 11, the present application provides a system for real-time measurement of thin film thickness using an acoustic wave element, which comprises at least one carrier, at least one acoustic wave element, and a computing unit.

[0043] As shown in Figure 9, three carriers are provided in the present embodiment, and each carrier is provided with an acoustic wave element on the side, which is used to detect the change of the thin film thickness formed on the surface of the carrier during film plating in real time and generate a resonance frequency. The resonance frequency of the acoustic wave element is between 100 MHz and 300 MHz. The acoustic wave element is one of Surface Acoustic Wave (SAW), Film Bulk Acoustic Resonator (FBAR), and Bulk Acoustic Waves-Solidly Mounted Resonator (BAW-SMR), and the above-mentioned acoustic wave elements all change in frequency with temperature. The acoustic wave element of the present embodiment is FBAR.

[0044] As mentioned above, when the surface of the carrier is coated with a thin film, the surface of the acoustic wave element is also coated with the same thin film to detect the change in the thickness of the thin film in real time. The resonance frequency of the acoustic wave element decreases with the increase in the thickness of the thin film. It is particularly noted that the resonance frequency of the acoustic wave element changes between 0.1% and 0.2% when the thickness of the thin film increases by 1 nm. Under the condition of a fixed temperature, the calculation unit generates a pre-correction film thickness-frequency two-dimensional coordinate system as shown in FIG. 1 by measuring the values of the thickness of the thin film and the resonance frequency. The present application measures the change in the resonance frequency with the increase in the thickness of the thin film under the conditions that the temperature of the cavity is respectively stabilized at 25°C, 40°C, 50°C and 100°C. The calculation unit obtains the values of the thickness of the thin film and the resonance frequency generated by different thicknesses of the thin film under the conditions of four different temperatures, and further obtains the corresponding pre-correction film thickness-frequency two-dimensional coordinate system, in which the X-axis is the thickness of the thin film and the Y-axis is the resonance frequency.

[0045] Please refer to the curve shown in FIG. 2, which is the relationship between the thickness of the thin film and the resonance frequency of the acoustic wave element with different resonance areas under the condition that the temperature of the cavity is 25°C. The resonance areas of the acoustic wave element are respectively 6400 μm 2 , 10000 μm 2 , 14400 μm 2 and 25600 μm 2 , and the thicknesses of the thin film are respectively 0 nm (i.e. no coating), 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm and 50 nm. The resonance frequency detected by the acoustic wave element gradually decreases with the increase in the thickness of the coating. From the above-mentioned pre-correction film thickness-frequency two-dimensional coordinate system, it can be seen that under the condition that the temperature of the cavity is unchanged, the resonance frequency detected by the acoustic wave element gradually decreases with the increase in the thickness of the thin film on the carrier.

[0046] When the temperature of the cavity continues to rise, the temperature of the acoustic wave element also rises, and the acoustic wave element detects the resonance frequency generated by the thickness of the thin film in real time, which decreases with the increase in the temperature. Under the condition of a fixed thickness of the thin film, the calculation unit generates a temperature-frequency compensation two-dimensional coordinate system as shown in FIG. 3 by detecting the values of the temperature of the cavity and the resonance frequency, in which the X-axis is the temperature of the cavity and the Y-axis is the resonance frequency. Further, when the effective resonance area of the acoustic wave element is 6400 μm 2The present application measures and records the change of resonant frequency with temperature rise under the conditions that the cavity temperature is 25℃, 40℃, 50℃ and 100℃ respectively when the carrier and the acoustic wave element have different film thicknesses of 0nm (i.e. no coating), 5nm, 10nm, 15nm, 30nm and 50nm. The calculation unit obtains the measurement values of cavity temperature and resonant frequency generated by different film thicknesses under four different temperature conditions through detection, and then obtains the corresponding temperature-frequency compensation two-dimensional coordinate system. The above-mentioned temperature-frequency compensation two-dimensional coordinate system is integrated as shown in FIG. 4. As can be seen from the above-mentioned temperature-frequency compensation two-dimensional coordinate system, under the condition that the film thickness of the carrier is unchanged, the cavity temperature gradually increases, and the resonant frequency detected by the acoustic wave element gradually decreases.

[0047] Then, the calculation unit further comprehensively operates the above-mentioned film thickness-frequency two-dimensional coordinate system before correction and the above-mentioned temperature-frequency compensation coordinate system to generate a film thickness measurement three-dimensional coordinate system as shown in FIG. 5. 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. Through the film thickness measurement three-dimensional coordinate system, the three-dimensional coordinates containing the corresponding values of the cavity temperature, the film thickness and the resonant frequency can be obtained. Therefore, when the acoustic wave element detects the film thickness, the detected resonant frequency and cavity temperature can be interpolated and searched in the film thickness measurement three-dimensional coordinate system to obtain a three-dimensional coordinate value of (cavity temperature-film thickness-resonant frequency), so that the corresponding film thickness can be obtained. The cavity temperature and the resonant frequency are measured intermittently during the coating process to achieve the function of measuring the film thickness in real time. The system is suitable for the coating environment of the carrier with a temperature change range of The range of the film thickness to be coated is

[0048] ​As shown in FIG. 9 and FIG. 10, the carriers 2 face a film deposition source 4, which forms a thin film on the surface of the carrier 2 by sputtering. The film deposition method can be evaporation, sputtering or chemical vapor deposition. A plurality of baffles 5 are arranged between the film deposition source 4 and the carriers 2. In this embodiment, three carriers 2 face a film deposition source 4, and at least two baffles 5 are arranged between the film deposition source 4 and the carriers 2, which can swing left and right. The baffles 5 are in communication with the computing unit, which obtains the real-time film thickness from the film thickness measurement three-dimensional coordinate system according to the real-time detection of the cavity temperature and the resonant frequency, and controls the relative position between the baffles 5 and the carriers 2 according to the real-time film thickness to adjust the uniformity of the film deposition of the film deposition source on the carriers. In detail, the baffles 5 are used to adjust the film deposition rate of the film deposition source, and the shielding area of the baffles 5 to the film deposition source 4 or the carriers 2 is inversely proportional to the film thickness. When the film thickness is thicker, it indicates that it is closer to the target set thickness, at which time the film deposition rate needs to be slowed down, so the computing unit controls the baffles 5 to move to increase the shielding area, adjust the shielding angle and the shielding distance, thereby reducing the film deposition rate and ensuring the uniformity of the film deposition of the carriers.

[0049] As shown in FIG. 8, the acoustic wave elements 1 are arranged 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 the MEMS switch elements 3 are arranged in an array. Further, each carrier is placed in a deposition area, and in other implementable modes, the deposition area can also be arranged close to the carrier. The surface area of each MEMS switch element on one side of the corresponding acoustic wave element is greater than the resonant effective area of the acoustic wave element, so as to completely shield the acoustic wave element 1, and the operation or shutdown of the corresponding acoustic wave element 1 is determined by opening and closing the MEMS switch 3, that is, when the MEMS switch 3 is opened, the corresponding acoustic wave element 1 operates and generates a resonant frequency; if the MEMS switch 3 is closed, the corresponding acoustic wave element 1 is shut down and stops operating, so that the corresponding operating acoustic wave elements can be flexibly adjusted according to the number of carriers to be measured. During the film thickness measurement process, at least one acoustic wave element is turned on as a measurement group to monitor the film thickness change of the carrier, and another acoustic wave element can be turned on as a comparison group at different film deposition times and temperatures, so that the resonant frequency detected by the comparison group is compared with the data of the measurement group to determine whether the resonant frequency detected by the measurement group has a problem. Or after a period of use, for example, after 1000 hours, the comparison group is turned on to verify the accuracy of the acoustic wave element.

[0050] In addition, Figures 2, 6, and 7 show the curves relating the resonant area of ​​the acoustic wave element, the SiO2 film thickness, and the resonant frequency. These curves were drawn at cavity temperatures of 25°C and 40°C, and film thicknesses of 0 nm (uncoated), 5 nm (nanometers), 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, and 50 nm, with an effective resonant area of ​​6400 μm. 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] As shown in Figure 11, 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] The application can also be applied to etching operation after film plating. When film plating, the resonance frequency decreases with the increase of the film thickness. When etching the film, the resonance frequency increases with the decrease of the film thickness, and the frequency decreases with the increase of the cavity temperature. After the film plating process of the carriers is completed, the etching operation is performed. The acoustic wave element is also used to measure the film thickness in real time by the calculation unit. The calculation unit obtains the film etching depth according to the increase of the resonance frequency, and then adjusts the film etching depth according to the process requirement.

[0058] From the above embodiments, the system for measuring the film thickness in real time by the acoustic wave element provided by the application can achieve the following improvement effects:

[0059] First, the film thickness is detected in real time to improve the film plating yield. The film thickness calculation three-dimensional coordinate system including the cavity temperature, the film thickness and the resonance frequency is constructed. In actual use, only the cavity temperature and the resonance frequency need to be detected. The above two data are searched in the film thickness calculation three-dimensional coordinate system to obtain the accurate film thickness. The calculation efficiency is high, and the key parameter of the film thickness in the process is fed back in real time. The operating personnel can adjust the operation parameters in time to ensure the uniformity of the film plating and improve the film plating yield.

[0060] Second, the resonance frequency change caused by the cavity temperature is automatically compensated, and the result accuracy is high. The temperature compensation layer is used in the prior art to compensate the temperature change of the cavity during film plating. However, the temperature compensation layer cannot be flexibly adjusted according to the actual production situation, so that the compensated temperature change is not accurate. The film thickness calculation three-dimensional coordinate system is established by a large amount of experimental data. The corresponding resonance frequency under different cavity temperature conditions is included. The resonance frequency actually measured is compensated by the resonance frequency in the film thickness calculation three-dimensional coordinate system, so that the accurate film thickness is obtained.

[0061] Third, the acoustic wave element can be flexibly selected. Compared with the prior art, the film thickness of the carrier can be detected after the temperature compensation layer is added to the acoustic wave element in the application. Therefore, most of the acoustic wave elements are suitable for the application.

[0062] Fourth, the film thickness detection can be applied to different processes. The film thickness detection in real time during film plating and etching can be applied to the application. The etching operation can be immediately converted after the film plating process is completed. The acoustic wave element of the application also detects the film thickness in real time by the calculation unit. When film plating, the resonance frequency decreases with the increase of the film thickness. When etching the film, the resonance frequency increases with the decrease of the film thickness, and the frequency decreases with the increase of the cavity temperature. The calculation unit obtains the film etching depth according to the increase of the resonance frequency, and then adjusts the film etching depth according to the process requirement.

[0063] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced by equivalents; 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 application.

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 plating environment of the carrier.

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 the thickness of a thin film in real time using an acoustic wave element 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.

Images