FBAR sensor-based film thickness measurement system and measurement method

Abstract

According to the film thickness measuring system and method based on the FBAR sensor, the fitting calibration curve database is established, and the FBAR sensor is embedded into the film deposition equipment, so that the film deposition thickness can be measured in real time, a wafer does not need to be taken out of a film deposition machine table for measurement, and the running time is shortened; in addition, the change of the deposition process can be reflected in real time by monitoring the change of the film deposition thickness in real time, the process parameters are adjusted in time accordingly, the process adjustment time is shortened, and the process optimization efficiency is improved.

Description

Technical Field

[0001] The present invention relates to thin film thickness measurement in the field of semiconductor technology, and in particular to an embedded thin film thickness measurement system and a measurement method based on a Film Bulk Acoustic Resonator (FBAR) sensor. Background Art

[0002] Thickness measurement is an indispensable measurement method in the microelectronics industry. The commonly used thickness measurement methods mainly include: 1. Ellipsometry (SE for short), which has high precision, but requires the use of an ellipsometer to collect spectra and build models, which is cumbersome and costly, and has certain limitations; 2. Spectral reflectance (SR for short), which uses a spectrometer to measure the reflectivity of a sample within a certain wavelength range, and iterates by changing the thickness of each layer of a multilayer film within a certain range, and then compares the calculated reflectivity with the actual measured reflectivity to calculate the actual film thickness. This method is suitable for thick film measurement; 3. Transmission electron microscope measurement method (TEM for short), which requires slicing and measurement using a transmission electron microscope, which is complex and highly destructive. In addition, none of the above methods can monitor process changes in real time.

[0003] In recent years, FBAR sensors have received extensive attention in the fields of radio frequency communication and biochemical sensing. FBAR sensors can be applied to chemical substance analysis, biological gene detection, protein analysis, etc. FBAR sensors are generally composed of a layer of piezoelectric film and upper and lower electrodes, wherein the upper and lower electrodes are respectively located on the upper and lower surfaces of the piezoelectric film, forming a "sandwich" sandwich structure. FBAR sensors are based on the principle of high-frequency electroacoustic resonance generated by piezoelectric film, and the resonant frequency, phase or amplitude of the sensor changes with the detected substance as the sensor response. The mass change sensitivity of the surface adsorption layer can reach the single molecular level, so it has a very broad application prospect. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a thin film thickness measurement system and measurement method based on FBAR sensor, which is used to solve the problems in the prior art in the microelectronics industry that the measurement method of thin film thickness measurement is cumbersome and costly, or can only perform thick film measurement or is destructive to thin film measurement, and cannot monitor the thickness change during the process in real time.

[0005] To achieve the above objectives and other related objectives, the present invention provides a method for measuring film thickness based on a FBAR sensor, the method comprising the following steps:

[0006] First, a fitting calibration curve database is established, wherein the fitting calibration curve database contains fitting calibration curves of different required material films, wherein the fitting calibration curve is a curve formed by the corresponding resonance frequency shift Δf under different deposition thicknesses of the same material film;

[0007] Then, the thickness of the film deposited on the surface of the wafer to be deposited is measured in real time, including:

[0008] (10) Installing the FBAR sensor below the wafer to be deposited;

[0009] (11) Powering on the FBAR sensor to start working;

[0010] (12) Setting preset parameters for deposition of a desired material film to perform film deposition on the wafer to be deposited, and retrieving a fitting calibration curve of the desired material film from the fitting calibration curve database; wherein the resonant frequency measured by the FBAR sensor before film deposition is defined as the fundamental frequency f 01 , the resonant frequency measured by the FBAR sensor after film deposition is f x1 ;

[0011] (13) The resonance frequency measured by the FBAR sensor is used to obtain the corresponding resonance frequency shift Δf1=f under different deposition thicknesses. x1 -f 01 The resonant frequency shift Δf1 is compared with the fitting calibration curve of the desired material film to directly obtain the deposition thickness of the film.

[0012] Optionally, the method for establishing the fitted calibration curve database comprises:

[0013] (20) Installing the FBAR sensor below the wafer to be deposited;

[0014] (21) Powering on the FBAR sensor to start working, and recording the fundamental frequency f0 of the FBAR sensor before thin film deposition;

[0015] (22) performing thin film deposition on the wafer to be deposited, and obtaining the corresponding resonant frequency f under different film deposition thicknesses through the FBAR sensor. x ;

[0016] (23) Obtain the corresponding resonant frequency shift Δf = f under different film deposition thicknesses x -f0;

[0017] (24) based on the resonance frequency shift Δf corresponding to the different film deposition thicknesses obtained above, a fitting calibration curve between the film deposition thickness and the resonance frequency shift Δf is drawn;

[0018] (25) Repeat the above steps (20) to (24) to obtain a plurality of fitting calibration curves of thin films of different desired materials, thereby establishing a database of fitting calibration curves of thin films of different desired materials.

[0019] Furthermore, in step (13), a network analyzer is used to obtain the corresponding resonant frequency shift Δf1 under different deposition thicknesses; when establishing the fitting calibration curve database, a network analyzer is used to obtain the corresponding resonant frequency shift Δf under different deposition thicknesses.

[0020] Optionally, in step (10), the FBAR sensors are arranged in an array below the entire wafer to be deposited.

[0021] Furthermore, all the FBAR sensors are powered on to achieve real-time monitoring of the uniformity of the film deposition thickness on the entire surface of the wafer to be deposited.

[0022] Furthermore, when the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited exceeds a preset value, the preset parameters of the thin film deposition are adjusted in real time, and the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited after adjustment is monitored in real time, so that the thickness uniformity of the thin film deposition on the surface of the wafer to be deposited is less than the preset value, so as to improve the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited.

[0023] Optionally, some of the FBAR sensors are powered on to achieve real-time monitoring of the uniformity of the film deposition thickness on the surface of the corresponding portion of the wafer to be deposited.

[0024] Further, the powered-on FBAR sensors are arranged in a transverse direction, in a longitudinal direction, or in a circumferential ring shape.

[0025] Optionally, the FBAR sensor is disposed on a supporting platform of a thin film deposition device.

[0026] The present invention also provides a film thickness measurement system based on an FBAR sensor, which realizes real-time measurement of the film deposition thickness on the surface of a wafer to be deposited. The measurement system comprises: an FBAR sensor, a resonance frequency shift calculation module, a fitting calibration curve generation module and a storage module; wherein,

[0027] The FBAR sensor is embedded in the thin film deposition equipment and is used to obtain the fundamental frequency f of the FBAR sensor before thin film deposition. 02 , and the corresponding resonance frequency f under different film deposition thicknesses after film deposition on the wafer to be deposited x2 ;

[0028] The resonance frequency shift calculation module is used to obtain the corresponding resonance frequency shift Δf2=f under different film deposition thicknesses. x2 -f 02;

[0029] The fitting calibration curve generating module is used to draw a fitting calibration curve of the film deposition thickness and the resonance frequency shift Δf2 based on the resonance frequency shift Δf2 corresponding to the different film deposition thicknesses obtained above;

[0030] The storage module is used to store the fitting calibration curves of different required material films, thereby forming a fitting calibration curve database.

[0031] Optionally, the resonance frequency shift calculation module is a network analyzer.

[0032] Optionally, the FBAR sensors are arranged in an array and embedded in a thin film deposition device.

[0033] As described above, the FBAR sensor-based thin film thickness measurement system and measurement method of the present invention can achieve real-time measurement of thin film deposition thickness by establishing a fitting calibration curve database and embedding the FBAR sensor in the thin film deposition equipment. The wafer does not need to be taken out of the thin film deposition machine for measurement, thereby reducing the running time. In addition, by real-time monitoring of the changes in the thin film deposition thickness, the changes in the deposition process can be reflected in real time, and the process parameters can be adjusted in time accordingly, thereby reducing the process adjustment time and improving the process optimization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram showing the cross-sectional structure of the FBAR sensor in the thin film thickness measurement system based on the FBAR sensor of the present invention.

[0035] Figure 2 It is a schematic diagram of the cross-sectional structure of the position arrangement of the FBAR sensor in the thin film deposition equipment in the thin film thickness measurement method based on the FBAR sensor of the present invention.

[0036] Figure 3 It is a schematic diagram of the cross-sectional structure after thin film deposition is performed on the wafer to be deposited in the thin film thickness measurement method based on the FBAR sensor of the present invention.

[0037] Figure 4 It is a schematic top view of the position structure of the FBAR sensor array on the supporting platform of the thin film deposition equipment in the thin film thickness measurement method based on the FBAR sensor of the present invention.

[0038] Figure 5 It shows the resonance frequency shift diagram corresponding to different film deposition thicknesses obtained by the network analyzer in the film thickness measurement method based on the FBAR sensor of the present invention.

[0039] Figure 6It is a schematic diagram showing a fitting calibration curve of a certain required material film in the film thickness measurement method based on the FBAR sensor of the present invention.

[0040] Component number description

[0041] 10 FBAR sensor

[0042] 11 FBAR sensor array

[0043] 12 Loading platform

[0044] 13 Wafer to be deposited

[0045] 14 Piezoelectric film layer

[0046] 15 Upper electrode layer

[0047] 16 Lower electrode layer

[0048] 17 Thin Film Deposition DETAILED DESCRIPTION

[0049] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0050] See also Figures 1 to 6 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0051] This embodiment provides a film thickness measurement method based on a FBAR sensor, and the measurement method mainly includes two steps:

[0052] S1: Establishing a fitting calibration curve database, wherein the fitting calibration curve database contains fitting calibration curves of thin films of different required materials, wherein the fitting calibration curve is a curve formed by the corresponding resonant frequency shift Δf under different deposition thicknesses of the same material film; and S2: Based on the fitting calibration curve database, real-time measurement of the thickness of the film deposited on the surface of the wafer to be deposited is performed.

[0053] The specific method of step S2 of real-time measuring the thickness of the film deposited on the surface of the wafer to be deposited comprises:

[0054] S20, installing the FBAR sensor below the wafer to be deposited;

[0055] S21, powering on the FBAR sensor to start working;

[0056] S22, setting preset parameters for deposition of a desired material thin film to perform thin film deposition on the wafer to be deposited, and retrieving a fitting calibration curve of the desired material thin film from the fitting calibration curve database; wherein the resonant frequency measured by the FBAR sensor before thin film deposition is defined as the fundamental frequency f 01 , the resonant frequency measured by the FBAR sensor after film deposition is f x1 The preset parameters for the deposition of the required material thin film here refer to all parameters related to the thin film deposition, such as the gas source, temperature, pressure, and flow rate of the deposition reaction, which are set according to the specific situation of different processes and are not limited in detail here;

[0057] S23, obtaining the corresponding resonant frequency shift Δf1=f under different deposition thicknesses by measuring the resonant frequency of the FBAR sensor x1 -f 01 , the resonant frequency shift Δf1 is compared with the fitting calibration curve of the required material film to directly obtain the deposition thickness of the film; the resonant frequency shift Δf1 can be obtained by using a conventional resonant frequency shift calculation module, for example, using a network analyzer, by transmitting the measured resonant frequency to the network analyzer, and obtaining the resonant frequency shift Δf1 waveform from the network analyzer.

[0058] The measurement method of this embodiment can achieve real-time measurement of thin film deposition thickness by establishing a fitting calibration curve database and embedding the FBAR sensor into the thin film deposition equipment. The wafer does not need to be taken out of the thin film deposition machine for measurement, thereby reducing the time for running goods. In addition, by real-time monitoring of changes in thin film deposition thickness, changes in the deposition process can be reflected in real time, and process parameters can be adjusted in time accordingly, thereby reducing process adjustment time and improving process optimization efficiency.

[0059] The measurement method of this embodiment can realize real-time monitoring of any thickness of any material in the existing semiconductor deposition process. Taking silicon oxide film as an example, the thickness of the deposited silicon oxide film per square centimeter can be When the thickness is 1000nm, the mass of silicon oxide increases by 220ng, which is completely in line with the detection limit of the current FBAR sensor. As long as it is within the thickness detection range of the FBAR sensor used.

[0060] As a specific example, in step S1, the method for establishing a fitting calibration curve database includes:

[0061] S10, installing the FBAR sensor 10 below the wafer 13 to be deposited, as shown in Figure 2 and Figure 4 As shown;

[0062] S11, power on the FBAR sensor 10 to start working, and record the fundamental frequency f0 of the FBAR sensor before thin film deposition, that is, the resonant frequency measured by the FBAR sensor 10 before thin film deposition on the wafer 13 to be deposited, such as Figure 2 As shown, the resonant frequency is not the resonant frequency of the FBAR sensor 10 itself, but the resonant frequency obtained by the FBAR sensor 10 after adding the mass of the undeposited wafer 13 to be deposited;

[0063] S12, performing thin film deposition 17 on the wafer 13 to be deposited, such as Figure 3 As shown, the corresponding resonant frequency f under different film deposition thicknesses is obtained by the FBAR sensor 10. x , wherein the film deposition thickness can be obtained by using conventional thickness measurement methods, for example, by slicing and measuring the film on the wafer to be deposited after film deposition. Therefore, different film deposition thicknesses can be obtained by slicing and measuring a plurality of wafers to be deposited with different film deposition thicknesses. For example, 10 wafers to be deposited with different film deposition thicknesses are selected and sliced ​​and measured to obtain 10 different film deposition thicknesses, and the corresponding resonant frequencies f of the FBAR sensor 10 under the 10 different film deposition thicknesses are obtained. x ,It should be explained here that the smaller thickness interval of the ,different film deposition thicknesses selected is, the larger thickness range is, the higher accuracy of the ,fitting calibration curve obtained subsequently is ,higher;

[0064] S13, obtain the corresponding resonance frequency shift Δf=f under different film deposition thicknesses x -f0, such as Figure 5 As shown, the resonance frequency shift data corresponding to different film deposition thicknesses are obtained; the resonance frequency shift can be obtained by using a conventional resonance frequency shift calculation module, for example, by using a network analyzer, by transmitting the measured resonance frequency to the network analyzer, and obtaining a resonance frequency shift Δf waveform diagram by the network analyzer;

[0065] S14, based on the resonance frequency shift Δf corresponding to different film deposition thicknesses obtained above, a fitting calibration curve of film deposition thickness and resonance frequency shift Δf is drawn, such as Figure 6 12 film deposition thicknesses and 12 corresponding resonant frequency shifts Δf were selected, and a fitting calibration curve was fitted through the 12 sets of data. As mentioned above, the more thickness data selected and the smaller the thickness interval, the higher the accuracy of the fitting calibration curve obtained;

[0066] S15. Repeat the above steps (S10) to (S14) to obtain fitting calibration curves of multiple films of different required materials, so as to establish a database of fitting calibration curves of films of different required materials; for example, insulating materials such as silicon oxide and silicon nitride in the semiconductor process, or semiconductor epitaxial materials such as silicon, germanium, and silicon carbide, and the database of fitting calibration curves can be gradually increased and improved according to actual needs and the development of semiconductor process technology to improve the universality of the database of fitting calibration curves.

[0067] The process of establishing the calibration curve database is realized by applying the inverse piezoelectric effect of the FBAR sensor. Figure 1 As shown, when the upper electrode 15 and the lower electrode 16 of the FBAR sensor 10 are connected to a DC regulated power supply, the piezoelectric film layer 14 is in an external electric field, and the charge polarization inside the piezoelectric film layer 14 causes internal deformation. The sound waves generated by the internal deformation of the piezoelectric film layer 14 form standing wave oscillations, generating a resonant frequency signal; Figure 2 and Figure 3 As shown, when there is mass adsorbed on the surface of the FBAR sensor 10, the resonant frequency of the FBAR sensor 10 will change, resulting in a resonant frequency shift Δf=f x -f0, where

[0068] f0=v / 2d

[0069]

[0070] f0 is the fundamental frequency when there is no mass adsorbed on the surface of the FBAR sensor, ν represents the velocity of the bulk acoustic wave, d represents the thickness of the piezoelectric film layer, μ0 is the Young's modulus of the piezoelectric film layer, ρ0 is the density of the piezoelectric film layer, A is the effective area of ​​the FBAR sensor, and Δm is the mass attached to the surface of the FBAR sensor. Therefore, the mass Δm adsorbed on the surface of the FBAR sensor can be detected according to the change in the resonant frequency. In addition, since the mass is the product of density and volume, when the density and surface area remain unchanged, the mass is a linear function of the thickness, so a one-to-one correspondence between the resonant frequency shift and the thickness of the adsorbed material adsorbed on the surface of the FBAR sensor can be obtained, that is, a fitting calibration curve.

[0071] like Figure 2 and Figure 4 As shown, as an example, when the thickness of the film deposited on the surface of the wafer to be deposited is measured in real time, the FBAR sensors 10 can be arranged in an array below the entire wafer to be deposited 13 to form an FBAR sensor array 11, so that the thickness of the film deposited in different areas of the wafer to be deposited 13 can be measured according to different requirements. For example, all the FBAR sensors 10 are powered on, so that the uniformity of the film deposition thickness on the surface of the entire wafer to be deposited 13 can be monitored in real time. Preferably, as Figure 3 As shown, when the thickness uniformity of the thin film deposition 17 on the surface of the entire wafer 13 to be deposited exceeds the preset value, the preset parameters of the thin film deposition can be adjusted in real time accordingly, and the thickness uniformity of the thin film deposition on the surface of the entire wafer to be deposited after adjustment can be monitored in real time, so that the thickness uniformity of the thin film deposition on the surface of the wafer to be deposited is less than the preset value, thereby improving the accuracy of the thickness uniformity of the thin film deposition on the surface of the entire wafer to be deposited and improving the deposition quality; in addition, it is also possible to choose to power on part of the FBAR sensor 10 to realize real-time monitoring of the thickness uniformity of the thin film deposition 17 on the surface of the corresponding part of the wafer to be deposited, for example, Figure 4 As shown, the powered-on FBAR sensors 10 can be arranged in a horizontal X direction, in a vertical Y direction, or in a circumferential ring shape, which can be specifically arranged according to actual needs.

[0072] like Figures 2 to 4 As shown, in actual measurement, the FBAR sensor 10 can be placed on a carrier 12 of a thin film deposition device. When the FBAR sensors 10 are arranged in an array, all FBAR sensors 10 are placed on the carrier 12. The measurement method of this embodiment is applicable to existing common thin film deposition processes, such as CVD process, ALD process, PVD process, etc.

[0073] like Figure 1 As shown, the structure of the FBAR sensor 10 mainly includes a piezoelectric film layer 14 and an upper electrode layer 15 and a lower electrode layer 16 located on both sides thereof, and may also include some electrode lead structures, packaging structures, etc., which are all conventional settings and are not overly limited here. The material of the piezoelectric film layer 14 can be selected from conventional materials suitable for preparing piezoelectric films, such as any one of aluminum nitride, zinc oxide and lead zirconate titanate, or at least two of them are doped. The material of the upper electrode layer 15 and the lower electrode layer 16 is selected from metal materials suitable for preparing FBAR sensors, such as gold or aluminum.

[0074] The above-mentioned film thickness measurement method based on FBAR sensor can be implemented based on a set of measurement system. The measurement system can be used to realize real-time measurement of the film deposition thickness on the surface of the wafer to be deposited. The measurement system includes: FBAR sensor, resonance frequency shift calculation module, fitting calibration curve generation module and storage module; wherein,

[0075] The FBAR sensor is embedded in the thin film deposition equipment and is used to obtain the fundamental frequency f of the FBAR sensor before thin film deposition. 02 , and the corresponding resonance frequency f under different film deposition thicknesses after film deposition on the wafer to be deposited x2 ;

[0076] The resonance frequency shift calculation module is used to obtain the corresponding resonance frequency shift Δf2=f under different film deposition thicknesses. x2 -f 02 ;

[0077] The fitting calibration curve generating module is used to draw a fitting calibration curve of the film deposition thickness and the resonance frequency shift Δf2 based on the resonance frequency shift Δf2 corresponding to the different film deposition thicknesses obtained above;

[0078] The storage module is used to store the fitting calibration curves of different required material films, thereby forming a fitting calibration curve database.

[0079] As an example, the resonance frequency shift calculation module may be a network analyzer.

[0080] As another example, the FBAR sensors are arranged in an array and embedded in a thin film deposition device.

[0081] It is worth mentioning that the modules mentioned above are all logic modules. In practical applications, a logic unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. In addition, in order to highlight the innovative part of the present application, the present embodiment does not introduce units that are not closely related to solving the technical problems proposed by the present application, but this does not mean that there are no other units in the present embodiment.

[0082] In summary, the FBAR sensor-based film thickness measurement system and measurement method of the present invention can achieve real-time measurement of film deposition thickness by establishing a fitted calibration curve database and embedding the FBAR sensor in the film deposition equipment. The wafer does not need to be taken out of the film deposition machine for measurement, which reduces the time for running goods. In addition, by real-time monitoring of the change in film deposition thickness, the change in deposition process can be reflected in real time, and the process parameters can be adjusted in time accordingly, reducing the process adjustment time and improving the process optimization efficiency. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0083] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A film thickness measurement method based on FBAR sensor, characterized in that: The measuring method comprises the following steps: First, a fitting calibration curve database is established, wherein the fitting calibration curve database contains fitting calibration curves of different required material films, wherein the fitting calibration curve is a curve formed by the corresponding resonance frequency shift Δf under different deposition thicknesses of the same material film; Then, the thickness of the film deposited on the surface of the wafer to be deposited is measured in real time, including: (10) Installing the FBAR sensor below the wafer to be deposited; (11) Powering on the FBAR sensor to start working; (12) Setting preset parameters for deposition of a desired material film to perform film deposition on the wafer to be deposited, and retrieving a fitting calibration curve of the desired material film from the fitting calibration curve database; wherein the resonant frequency measured by the FBAR sensor before film deposition is defined as the fundamental frequency f 01 , the resonant frequency measured by the FBAR sensor after film deposition is f x1 ; (13) The resonance frequency measured by the FBAR sensor is used to obtain the corresponding resonance frequency shift Δf1=f under different deposition thicknesses. x1 -f 01 The resonant frequency shift Δf1 is compared with the fitting calibration curve of the desired material film to directly obtain the deposition thickness of the film.

2. The thin film thickness measurement method based on FBAR sensor according to claim 1, characterized in that: The method for establishing the fitted calibration curve database comprises: (20) Installing the FBAR sensor below the wafer to be deposited; (21) Powering on the FBAR sensor to start working, and recording the fundamental frequency f0 of the FBAR sensor before thin film deposition; (22) performing thin film deposition on the wafer to be deposited, and obtaining the corresponding resonant frequency f under different film deposition thicknesses through the FBAR sensor. x ; (23) Obtain the corresponding resonant frequency shift Δf = f under different film deposition thicknesses x -f0; (24) based on the resonance frequency shift Δf corresponding to the different film deposition thicknesses obtained above, a fitting calibration curve between the film deposition thickness and the resonance frequency shift Δf is drawn; (25) Repeat the above steps (20) to (24) to obtain a plurality of fitting calibration curves of thin films of different desired materials, thereby establishing a database of fitting calibration curves of thin films of different desired materials.

3. The thin film thickness measurement method based on FBAR sensor according to claim 1 or 2, characterized in that: In step (13), a network analyzer is used to obtain the corresponding resonant frequency shift Δf1 under different deposition thicknesses; when establishing the fitting calibration curve database, a network analyzer is used to obtain the corresponding resonant frequency shift Δf under different deposition thicknesses.

4. The thin film thickness measurement method based on FBAR sensor according to claim 1, characterized in that: In step (10), the FBAR sensors are arranged in an array below the entire wafer to be deposited.

5. The thin film thickness measurement method based on FBAR sensor according to claim 4, characterized in that: All the FBAR sensors are powered on to achieve real-time monitoring of the uniformity of the film deposition thickness on the entire surface of the wafer to be deposited.

6. The thin film thickness measurement method based on FBAR sensor according to claim 5, characterized in that: When the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited exceeds a preset value, the preset parameters of the thin film deposition are adjusted in real time, and the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited after adjustment is monitored in real time, so that the thickness uniformity of the thin film deposition on the surface of the wafer to be deposited is less than the preset value, so as to improve the thickness uniformity of the thin film deposition on the entire surface of the wafer to be deposited.

7. The method for measuring film thickness based on FBAR sensor according to claim 4, characterized in that: Powering on some of the FBAR sensors can achieve real-time monitoring of the uniformity of the film deposition thickness on the surface of the corresponding portion of the wafer to be deposited.

8. The thin film thickness measurement method based on FBAR sensor according to claim 7, characterized in that: The powered-on FBAR sensors are arranged in a transverse direction, a longitudinal direction, or a circumferential ring shape.

9. The thin film thickness measurement method based on FBAR sensor according to claim 1, characterized in that: The FBAR sensor is placed on a supporting platform of a thin film deposition device.

10. A film thickness measurement system based on FBAR sensor, characterized in that: The real-time measurement of the thickness of the thin film deposited on the surface of the wafer to be deposited is realized, and the measurement system includes: an FBAR sensor, a resonance frequency shift calculation module, a fitting calibration curve generation module and a storage module; wherein, The FBAR sensor is embedded in the thin film deposition equipment and is used to obtain the fundamental frequency f of the FBAR sensor before thin film deposition. 02 , and the corresponding resonance frequency f under different film deposition thicknesses after film deposition on the wafer to be deposited x2 ; The resonance frequency shift calculation module is used to obtain the corresponding resonance frequency shift Δf2=f under different film deposition thicknesses. x2 -f 02 ; The fitting calibration curve generating module is used to draw a fitting calibration curve of the film deposition thickness and the resonance frequency shift Δf2 based on the resonance frequency shift Δf2 corresponding to the different film deposition thicknesses obtained above; The storage module is used to store the fitting calibration curves of different required material films, thereby forming a fitting calibration curve database.

11. The thin film thickness measurement system based on FBAR sensor according to claim 10, characterized in that: The resonance frequency shift calculation module is a network analyzer.

12. The thin film thickness measurement system based on FBAR sensor according to claim 10, characterized in that: The FBAR sensors are arranged in an array and embedded in a thin film deposition device.

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