Single-layer chip integrated reading device with thin film mechanical oscillator and preparation method

Abstract

The present application provides a single-layer chip integrated reading device with a thin film mechanical vibrator and a preparation method, which relates to the field of piezoelectric material transducer technology. The single-layer chip integrated reading device includes: a substrate substrate; a first metallization layer; a piezoelectric material layer; a sacrificial material layer; a high tensile stress film; a second metallization layer, which forms an electric field with the first metallization layer; when an external driving signal drives the thin film mechanical vibrator on the high tensile stress film, the thin film mechanical vibrator drives the second metallization layer to vibrate, thereby changing the electric field between the first metallization layer and the second metallization layer, so that the phonons emitted by the piezoelectric material layer to the substrate substrate are changed, so as to form bound phonons in the phonon Fabry-Perot cavity, realize the bulk acoustic wave coupling between the thin film mechanical vibrator on the high tensile stress film and the substrate substrate, and obtain the thin film mechanical vibrator information on the high tensile stress film, which is conducive to improving the quality and yield of the thin film mechanical vibrator, and is conducive to the miniaturization and integration of the device.

Description

Technical Field

[0001] The present application relates to the technical field of piezoelectric material transducer technology, and in particular to a single-layer chip integrated reading device with a thin film mechanical oscillator and a preparation method thereof. Background Art

[0002] At present, the quantum ground state cooling of the vibration mode of the macroscopic mechanical oscillator with high quality factor can be achieved through sideband cooling and other technologies, thereby cooling the macroscopic object to the quantum region, showing an increasingly broad application prospect in the fields of quantum sensing, quantum information storage and conversion, and quantum precision measurement. Among them, the thin film mechanical oscillator made of high tensile stress film is an excellent choice for this macroscopic mechanical oscillator because it is easier to achieve ultra-high quality factor.

[0003] At present, the state information of this thin film mechanical oscillator is mainly read by microwave field or light field coupling, among which:

[0004] Microwave field reading requires that the thin film mechanical oscillator be metallized and then coupled with a microwave resonant cavity. The microwave resonant cavity and the thin film mechanical oscillator are processed and prepared on two chips respectively, and finally connected together by flip-chip welding or other methods to form spatial capacitive coupling. When flip-chip welding is connected, a certain pressure needs to be applied to the thin film mechanical oscillator for pressing. This pressure can easily cause the high tensile stress thin film mechanical oscillator to deform and rupture, reducing the quality and yield of the device. Light field reading requires that the thin film mechanical oscillator be placed in an optical FP cavity. The size of the FP cavity is in the order of centimeters. The optical FP cavity is large and difficult to adjust. Environmental vibration and other noise can easily affect the operating frequency and quality factor of the optical FP cavity, making it difficult to read out the state of the thin film mechanical oscillator through the optical FP cavity.

[0005] Therefore, whether microwave field reading or optical field reading is used, the reading structure and the thin film mechanical oscillator cannot be prepared on the same chip, so the entire device structure and processing technology are relatively complicated. Summary of the invention

[0006] In order to solve at least one of the above problems, the present application proposes a single-layer chip integrated reading device with a thin film mechanical oscillator and a preparation method thereof.

[0007] According to the first aspect of the present application, at least one embodiment of the present application provides a single-layer chip integrated reading device with a thin film mechanical oscillator, comprising: a substrate substrate, two surfaces of the substrate substrate forming a phonon Fabry-Perot cavity; a first metallization layer grown on the substrate substrate; a piezoelectric material layer grown on the first metallization layer and used to generate phonons and emit them into the substrate substrate; a sacrificial material layer grown on the piezoelectric material layer; a high tensile stress film grown on the sacrificial material layer and forming a thin film mechanical oscillator in the high tensile stress film; a second metallization layer grown on the high tensile stress film An electric field is formed on the stress film with the first metallization layer; wherein when an external driving signal drives the thin film mechanical oscillator on the high tensile stress film, the thin film mechanical oscillator drives the second metallization layer to vibrate, thereby changing the electric field between the first metallization layer and the second metallization layer, so that the phonons emitted from the piezoelectric material layer to the substrate substrate are changed, so as to form bound phonons in the phonon Fabry-Perot cavity, realize the bulk acoustic wave coupling of the thin film mechanical oscillator on the high tensile stress film and the substrate substrate, and obtain the information of the thin film mechanical oscillator on the high tensile stress film.

[0008] For example, in some embodiments of the present application, the second metallization layer has a preset pattern; the high tensile stress film is centered on the preset pattern and has a plurality of etching windows periodically arranged around it to form the thin film mechanical oscillator.

[0009] For example, in some embodiments of the present application, the substrate substrate includes sapphire.

[0010] For example, in some embodiments of the present application, the first metallization layer and the second metallization layer are semiconductor micro-nano-processed metal materials, including gold and / or aluminum.

[0011] For example, in some embodiments of the present application, the piezoelectric material layer is a piezoelectric thin film material that can be grown by micro-nano processing, including aluminum nitride and / or lithium niobate.

[0012] For example, in some embodiments of the present application, the sacrificial material layer is a polysilicon material.

[0013] For example, in some embodiments of the present application, the high tensile stress film is made of silicon nitride and / or silicon carbide material.

[0014] According to the second aspect of the present application, at least one embodiment of the present application provides a preparation method for preparing a single-layer chip integrated reading device as described in any one of the first aspects, the preparation method comprising: depositing the first metallization layer on the substrate substrate; depositing the piezoelectric material layer on the first metallization layer; depositing the sacrificial material layer on the piezoelectric material layer; depositing the high tensile stress film on the sacrificial material layer; depositing the second metallization layer on the high tensile stress film; etching a preset pattern on the second metallization layer; windowing to remove the high tensile stress film to form a periodically arranged window area to form a thin film mechanical oscillator area and expose the sacrificial material layer; etching to release the sacrificial material layer corresponding to the periodically arranged window area in the high tensile stress film.

[0015] For example, in some embodiments of the present application, the windowing removes the high-tensile stress film to form periodically arranged window areas to form a thin film mechanical oscillator area and expose the sacrificial material layer, including: taking the preset pattern as the center, periodically etching the high-tensile stress film in all directions to form a plurality of etching windows in the high-tensile stress film to form the thin film mechanical oscillator area.

[0016] For example, in some embodiments of the present application, the etching releases the sacrificial material layer corresponding to the periodically arranged window areas in the high-tensile stress film, including: etching the sacrificial material layer using an isotropic etching method, so that the material of the sacrificial material layer corresponding to the periodically arranged window areas in the high-tensile stress film is etched and released, and the material of the sacrificial material layer in the surrounding areas is retained to support the high-tensile stress film.

[0017] Through the above-mentioned example embodiments, the present application provides a single-layer chip integrated reading device and preparation method with a thin film mechanical oscillator, which realizes the inclusion of a thin film mechanical oscillator and a reading structure on a single-layer chip through semiconductor processing technology, simplifies the processing and preparation process of the thin film mechanical oscillator device, is beneficial to improving the quality and yield of the thin film mechanical oscillator, and is beneficial to the miniaturization and integration of the device.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] By describing in detail exemplary embodiments thereof with reference to the accompanying drawings, the above and other objects, features and advantages of the present application will become more apparent. The accompanying drawings described below are only some embodiments of the present application, and are not intended to limit the present application.

[0020] Figure 1A schematic diagram showing a method for preparing a single-layer chip integrated reading device with a thin film mechanical oscillator according to an exemplary embodiment;

[0021] Figure 2 A front view of an exemplary single-layer chip-integrated reader device with a thin film mechanical vibrator is shown. DETAILED DESCRIPTION

[0022] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0023] The described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of these specific details, or other modes, components, materials, devices, etc. may be adopted. In these cases, known structures, methods, devices, implementations, materials or operations will not be shown or described in detail.

[0024] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0025] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0026] Those skilled in the art will appreciate that the drawings are merely schematic diagrams of example embodiments, and the modules or processes in the drawings are not necessarily necessary for implementing the present application, and therefore cannot be used to limit the scope of protection of the present application.

[0027] The present application provides a single-layer chip integrated reading device with a thin film mechanical oscillator.

[0028] The single-layer chip integrated reading device with a thin film mechanical oscillator comprises: a substrate substrate 1, a first metallization layer 2, a piezoelectric material layer 3, a sacrificial material layer 4, a high tensile stress film 5 and a second metallization layer 6.

[0029] The first metallization layer 2 is grown on the substrate substrate 1 , and the piezoelectric material layer 3 is grown on the first metallization layer 2 .

[0030] The piezoelectric material layer 3, as a phonon source of bulk acoustic waves, can generate phonons of various vibration frequencies, and the generated phonons are emitted into the substrate substrate 1. The two surfaces of the substrate substrate 1 constitute a phonon Fabry-Perot cavity (FP).

[0031] The free spectral spacing of the phononic Fabry-Perot cavity ,in is the longitudinal body acoustic wave velocity in the substrate 1, d is the thickness of the substrate 1, and when the sapphire with a thickness of 0.25 mm is used as the substrate 1, the free spectrum spacing The phonon Fabry-Perot cavity will confine the phonons of a specific mode emitted from the piezoelectric material layer 3 in the phonon Fabry-Perot cavity with this free spectrum to form a series of bulk acoustic wave modes.

[0032] The sacrificial material layer 4 is grown on the piezoelectric material layer 3 .

[0033] The high tensile stress film 5 is grown on the sacrificial material layer 4 and forms a thin film mechanical oscillator in the high tensile stress film 5. The second metallization layer 6 is grown on the high tensile stress film 5 and forms an electric field with the first metallization layer 2.

[0034] According to an exemplary embodiment, the second metallization layer 6 has a preset pattern. The high tensile stress film 5 is centered on the preset pattern and has a plurality of etching windows periodically arranged around it to form a thin film mechanical oscillator.

[0035] The in-plane tensile stress of the high tensile stress film 5 itself can keep the film in a taut state. The defects in the middle part of the periodic windowing of the high tensile stress film 5 form a thin film mechanical oscillator. For example, the defect size is about 500um in diameter. When the tensile stress inside the high tensile stress film 5 is 1GPa, the fundamental vibration mode frequency of the thin film mechanical oscillator is about 700kHz.

[0036] According to some embodiments, a high tensile stress film refers to a film material having high tensile stress inside itself, and the tensile stress is generally above 1 GPa.

[0037] In the case where an external driving signal drives the thin film mechanical vibrator on the high tensile stress film 5, the thin film mechanical vibrator drives the second metallization layer 6 deposited on the surface to vibrate, and the vibration of the second metallization layer 6 further changes the electric field between the first metallization layer 2 and the second metallization layer 6, and the piezoelectric vibration of the piezoelectric material layer 3 also changes with the electric field, thereby changing the phonons emitted by the piezoelectric material layer 3 to the substrate substrate 1, so as to form bound phonons in the phonon Fabry-Perot cavity in the substrate substrate 1. The piezoelectric material layer 3 is used as an intermediate conversion medium to achieve the bulk acoustic wave coupling between the thin film mechanical vibrator on the high tensile stress film 5 and the substrate substrate 1, and the bound phonon information in the phonon Fabry-Perot cavity in the substrate substrate 1 is read through the second metallization layer 6, so that the thin film mechanical vibrator information on the high tensile stress film 5 can be characterized.

[0038] According to some embodiments, the thin film mechanical oscillator information includes the signal decay time constant T and the quality factor of the thin film mechanical oscillator. .

[0039] According to some embodiments, the substrate substrate 1 is selected to be sapphire material with a thickness of 0.25 mm. Sapphire has excellent bulk acoustic wave transmission performance, its longitudinal bulk acoustic wave velocity can reach 1.19E5m / s, and the acoustic wave transmission loss is small, and it can be used as a good acoustic device.

[0040] The first metallization layer 2 and the second metallization layer 6 can be made of common semiconductor micro-nano processing metal materials, such as gold, aluminum, etc., with a thickness of 50 nm.

[0041] The piezoelectric material layer 3 is made of a piezoelectric thin film material that can be grown by micro-nano processing, such as aluminum nitride, lithium niobate, etc., with a thickness of about 1 um. The piezoelectric material layer 3 can realize the conversion between mechanical vibration and electrical energy through the piezoelectric effect of the material itself.

[0042] The sacrificial material layer 4 is made of polysilicon material, which can ensure the high temperature conditions required for the subsequent growth of the high tensile stress film 5 by LPCVD. The thickness of the sacrificial material layer 4 is approximately between 200nm and 1um, and the thickness can be adjusted according to the required capacitance between the designed second metallization layer 6 and the first metallization layer 2.

[0043] The high tensile stress film 5 is made of silicon nitride or silicon carbide, with a thickness of 100 nm and a maximum in-plane tensile stress of more than 2 GPa.

[0044] Figure 1 A schematic diagram of a method for preparing a single-layer chip integrated reading device with a thin film mechanical oscillator according to an exemplary embodiment is shown.

[0045] like Figure 1 As shown, the preparation method comprises:

[0046] 1. Deposit the first metallization layer on the substrate.

[0047] A 250 um thick sapphire is selected as the substrate 1. A layer of gold or aluminum material with a thickness of 50 nm is deposited on the substrate 1 as the first metallization layer 2 by micro-nano processing techniques such as evaporation or sputtering.

[0048] 2. Deposit a piezoelectric material layer on the first metallization layer.

[0049] A layer of aluminum nitride or lithium niobate with a thickness of 1 um is deposited on the surface of the first metallization layer 2 by metal-organic chemical vapor deposition (MOCVD) as the piezoelectric material layer 3 .

[0050] 3. Depositing a sacrificial material layer on the piezoelectric material layer.

[0051] A layer of polysilicon with a thickness of 200 nm to 1 um is deposited on the surface of the piezoelectric material layer 3 by plasma enhanced chemical vapor deposition (PECVD) technology as a sacrificial material layer 4 .

[0052] 4. Depositing a high tensile stress film on the sacrificial material layer.

[0053] A layer of silicon nitride or silicon carbide with a thickness of 100 nm is deposited on the surface of the sacrificial material layer 4 by low pressure chemical vapor deposition (LPCVD) as the in-plane high tensile stress film 5 .

[0054] 5. Depositing a second metallization layer on the high tensile stress film.

[0055] A layer of gold or aluminum material with a thickness of 20 nm is deposited on the surface of the high tensile stress film 5 by micro-nano processing techniques such as evaporation or sputtering as the second metallization layer 6 .

[0056] 6. Etch a preset pattern on the second metallization layer.

[0057] The pattern of the second metallization layer 6 is defined by photolithography and wet etching or dry etching.

[0058] 7. Windowing removes the high tensile stress film to form a periodically arranged window area to form a thin film mechanical oscillator area and expose the sacrificial material layer.

[0059] Through a dry etching process such as reactive ion etching, a portion of the high tensile stress film 5 is removed by windowing to expose the sacrificial material layer 4 below. The high tensile stress film 5 is periodically etched around the second metallization layer 6 pattern as the center, so that the high tensile stress film 5 forms a plurality of etching windows, and the plurality of etching windows are arranged periodically to form a defect structure in the periodically arranged windows, i.e., a thin film mechanical oscillator region formed by the high tensile stress film 5, such as Figure 2 shown.

[0060] According to some embodiments, the central circle of the second metallization layer 6 determines the spatial position of the bulk acoustic wave mode of the single-layer chip integrated reading device with a thin film mechanical vibrator. The spatial position of the bulk acoustic wave mode is the longitudinal acoustic wave mode in the space corresponding to the central circular part of the second metallization layer 6. The central circular position of the second metallization layer 6 is generally selected as the middle of the thin film mechanical vibrator formed by the high tensile stress film 5, and also corresponds to the middle position of the entire chip device. The size of the central circle of the second metallization layer 6 will affect the coupling strength between the thin film mechanical vibrator formed by the high tensile stress film 5 and the piezoelectric material layer 3. When the size is larger, the coupling strength is stronger. The size of the central circle of the second metallization layer 6 also determines the size of the space occupied by the bulk acoustic wave in the substrate substrate 1. When the size is larger, the corresponding space size of the bulk acoustic wave is larger, and thus the material defects and surface unevenness of the substrate substrate 1 are more affected, which will cause the quality factor of the bulk acoustic wave mode to decrease. Based on the comprehensive consideration of the above two points, the diameter of the central circle of the second metallization layer 6 is generally selected to be between 200um and 500um.

[0061] The present application takes the case where the central pattern of the second metallization layer 6 is a circle as an example, but the present application is not limited thereto, and the set pattern of the second metallization layer 6 can be other patterns.

[0062] 8. Etching to release the sacrificial material layer corresponding to the periodically arranged window regions in the high tensile stress film.

[0063] The sacrificial material layer 4 under the windowed portion of the high-tensile stress film 5 is released through a vapor phase release process. Since the vapor phase release process is used and the sacrificial material layer 4 is etched by an isotropic etching method, the sacrificial material layer 4 can also be laterally etched through the windows of the high-tensile stress film 5. By controlling the etching time, the material of the sacrificial material layer 4 corresponding to the periodically arranged window area in the high-tensile stress film 5 is etched and released, and most of the sacrificial material layer 4 is retained at the peripheral edge due to its large lateral size. The retained sacrificial material layer 4 is used to support the high-tensile stress film 5.

[0064] The present application provides a single-layer chip integrated reading device and preparation method with a thin film mechanical oscillator. Through semiconductor processing technology, a thin film mechanical oscillator and a reading structure are simultaneously included on a single-layer chip, which simplifies the processing and preparation process of the thin film mechanical oscillator device. There is no need for flip-chip welding and other operations that may cause certain damage to the quality of the thin film mechanical oscillator, which is beneficial to improving the quality and yield of the thin film mechanical oscillator. There is no need for large-size structures such as optical FP cavities, which is beneficial to the miniaturization and integration of devices.

[0065] The present application also provides an information reading method of a single-layer chip integrated reading device with a thin film mechanical oscillator.

[0066] A method for reading thin film mechanical vibrator information of a single-layer chip integrated reading device having a thin film mechanical vibrator comprises the following steps:

[0067] 1. A single-layer chip integrated reading device with a thin film mechanical oscillator is prepared through the above-mentioned preparation process steps.

[0068] 2. Connect the second metallization layer 6 through a network signal analyzer to perform reflection transmission characteristic test, and obtain a series of absorption resonance peaks. Each resonance peak corresponds to a phonon mode in the substrate 1. Each resonance peak is distributed at equal frequency intervals, and the frequency interval is the free spectrum spacing of the phonon mode in the substrate 1. .

[0069] 3. Select one of the phonon modes as the measurement object and record the resonant frequency as , a frequency of The driving signal, scanning frequency, when the resonant frequency is When a transmission frequency window appears in the middle of the absorption resonance peak of the phonon mode reflection transmission characteristics, the film mechanical oscillator and the phonon mode form an electromagnetically induced transparency phenomenon. That is, the vibration mode frequency of the corresponding thin film mechanical oscillator .

[0070] 4. Apply a frequency of and the frequency is The two signals will excite the vibration of the mechanical oscillator. After a period of time, the frequency is removed. The driving signal of At the same time, the signal acquisition and recording equipment such as the spectrum analyzer collects the signal with a frequency of Since the vibration mode of the thin film mechanical oscillator is coupled with the phonon mode in the substrate 1, the thermal noise vibration of the thin film mechanical oscillator will pass through the frequency The driving signal is transferred to the phonon mode in the substrate 1 The frequency collected by the signal acquisition and recording equipment such as spectrum analyzer is The signal contains the vibration information of the mechanical oscillator. The attenuation of the signal intensity is proportional to the vibration attenuation of the thin film mechanical oscillator, thereby obtaining the signal attenuation time constant T and quality factor of the thin film mechanical oscillator. .

[0071] It should be clearly understood that the present application describes how to form and use specific examples, but the present application is not limited to any details of these examples. On the contrary, based on the teaching of the content disclosed in the present application, these principles can be applied to many other embodiments.

[0072] In addition, it should be noted that the above figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, and are not intended to be limiting. It is easy to understand that the processes shown in the above figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0073] The exemplary embodiments of the present application are specifically shown and described above. It should be understood that the present application is not limited to the detailed structures, configurations or implementations described herein; on the contrary, the present application is intended to cover various modifications and equivalent configurations included in the spirit and scope of the appended claims.

Claims

1. A single-layer chip integrated reading device with a thin film mechanical oscillator, characterized in that: include: A substrate substrate, two surfaces of which constitute a phonon Fabry-Perot cavity; A first metallization layer is grown on the substrate; A piezoelectric material layer, grown on the first metallization layer, for generating phonons to be emitted into the substrate; a sacrificial material layer, grown on the piezoelectric material layer; A high tensile stress film is grown on the sacrificial material layer and forms a thin film mechanical oscillator in the high tensile stress film; a second metallization layer, grown on the high tensile stress film, and forming an electric field with the first metallization layer; When an external driving signal drives the thin film mechanical oscillator on the high tensile stress film, the thin film mechanical oscillator drives the second metallization layer to vibrate, thereby changing the electric field between the first metallization layer and the second metallization layer, causing the phonons emitted from the piezoelectric material layer to the substrate to change, so as to form bound phonons in the phonon Fabry-Perot cavity, realize the bulk acoustic wave coupling of the thin film mechanical oscillator on the high tensile stress film and the substrate, and obtain the information of the thin film mechanical oscillator on the high tensile stress film.

2. The single-layer chip integrated reading device according to claim 1, characterized in that: The second metallization layer has a preset pattern; The high tensile stress film is centered on the preset pattern, and a plurality of etching windows are periodically arranged around it to form the thin film mechanical oscillator.

3. The single-layer chip integrated reading device according to claim 1, characterized in that: The substrate base comprises sapphire.

4. The single-layer chip integrated reading device according to claim 1, characterized in that: The first metallization layer and the second metallization layer are made of semiconductor micro-nano processing metal materials, including gold and / or aluminum.

5. The single-layer chip integrated reading device according to claim 1, characterized in that: The piezoelectric material layer is a piezoelectric thin film material that can be grown by micro-nano processing, including aluminum nitride and / or lithium niobate.

6. The single-layer chip integrated reading device according to claim 1, characterized in that: The sacrificial material layer is made of polysilicon material.

7. The single-layer chip integrated reading device according to claim 1, characterized in that: The high tensile stress film is made of silicon nitride and / or silicon carbide material.

8. A preparation method, characterized in that: Used to prepare a single-layer chip integrated reading device as claimed in any one of claims 1 to 7, the preparation method comprising: Depositing the first metallization layer on the substrate substrate; depositing the piezoelectric material layer on the first metallization layer; depositing the sacrificial material layer on the piezoelectric material layer; depositing the high tensile stress film on the sacrificial material layer; depositing the second metallization layer on the high tensile stress film; Etching a preset pattern on the second metallization layer; Windowing to remove the high tensile stress film to form a periodically arranged window area to form a thin film mechanical oscillator area and expose the sacrificial material layer; The sacrificial material layer corresponding to the periodically arranged window regions in the high tensile stress film is released by etching.

9. The preparation method according to claim 8, characterized in that: The windowing removes the high tensile stress film to form a periodically arranged window area to form a thin film mechanical oscillator area and expose the sacrificial material layer, including: Taking the preset pattern as the center, the high tensile stress film is periodically etched in all directions to form a plurality of etching windows in the high tensile stress film to form the thin film mechanical oscillator region.

10. The preparation method according to claim 8, characterized in that: The etching releases the sacrificial material layer corresponding to the periodically arranged window regions in the high tensile stress film, comprising: The sacrificial material layer is etched by an isotropic etching method, so that the material of the sacrificial material layer corresponding to the periodically arranged window area in the high tensile stress film is etched and released, and the material of the sacrificial material layer around is retained to support the high tensile stress film.

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