Mechanical oscillator quantum device based on superconducting film and preparation method thereof

Abstract

The present application discloses a mechanical oscillator quantum device based on superconducting film and its preparation method. It includes: preparation of a bottom electrode, a first feedback circuit and an overlay mark structure; preparation of a sacrificial layer structure, the sacrificial layer structure includes a tympanic membrane area and an outward extension structure, and the edge contour of the sacrificial layer structure is consistent with the contour of the modified second photoresist pattern; preparation of a top electrode and a second feedback circuit structure, and then forming a release window structure on the first surface of the top electrode; and etching the sacrificial layer structure so that the top electrode in the tympanic membrane area forms a suspended structure. The mechanical oscillator quantum device of the present application is provided with a release window structure periodically arranged with equal spacing in a basic structural unit at the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area. When the sacrificial layer film in the tympanic membrane area is etched through the release window structure, the suspended structure formed by the superconducting film in the tympanic membrane area presents a uniform morphology, so that the device has good stability.

Description

Technical Field

[0001] The present application relates to the technical field of quantum devices, and in particular to a mechanical oscillator quantum device based on a superconducting film and a preparation method thereof. Background Art

[0002] Micro-nano devices based on radiation pressure interaction of mechanical oscillators of semiconductor thin film materials have been widely used in cutting-edge scientific research fields such as precision measurement and sensing, testing of basic problems in quantum mechanics, and hybrid quantum information processing. In recent years, based on micro-nano processing technology, the preparation and research of quantum devices of various types of oscillators have made unprecedented progress. As an important type of solid-state quantum information processing device, oscillator quantum devices also have important applications in the fields of quantum information and quantum computing, including the preparation, transmission, and storage of quantum states, and as interfaces between various types of quantum systems.

[0003] As a type of solid-state quantum information processing device, the preparation technology of the tympanic membrane mechanical oscillator quantum device relies entirely on micro-nano processing technology. The three layers of device materials of the tympanic membrane mechanical oscillator device are stacked together in sequence through micro-processing technology.

[0004] In the current processing technology, a release port is reserved on the side of the tympanic membrane area. When the sacrificial layer film in the middle of the tympanic membrane area is completely etched, the superconducting film layer of the top electrode forms a suspended structure. In this way, at the step of the superconducting film of the top electrode, due to the influence of the relatively steep step, the mechanical strength of the film at the step is very weak, which often leads to the collapse of the suspended film due to insufficient mechanical strength of the superconducting film layer of the top electrode at the step. In addition, this method of reserving a release port on the side will result in a non-uniform morphology after the top electrode forms a suspended structure, which ultimately leads to poor stability of the prepared device. Summary of the invention

[0005] In order to solve the above-mentioned deficiencies in the art, the present application aims to provide a mechanical oscillator quantum device based on superconducting film and a preparation method thereof.

[0006] According to one aspect of the present application, a method for preparing a mechanical oscillator quantum device based on a superconducting film is provided, comprising:

[0007] The bottom electrode, the first feedback circuit and the overlay mark structure are prepared, including:

[0008] forming a first photoresist pattern on a first surface of the substrate using a first photoresist;

[0009] forming a bottom electrode, a first feedback circuit and an overlay mark structure on a first surface of the substrate by a first photoresist pattern;

[0010] Preparation of sacrificial layer structure, including:

[0011] Growing a sacrificial layer film on the first surface of the substrate to cover the bottom electrode, the first feedback circuit and the overlay mark structure;

[0012] Forming a second photoresist pattern on a predetermined area of ​​the surface of the sacrificial layer film by using a second photoresist, wherein the second photoresist pattern is used to form a preset sacrificial layer structure;

[0013] Performing a reflow process on the substrate formed with the second photoresist pattern to obtain a corrected second photoresist pattern having a uniform arc-shaped edge; and

[0014] Removing the sacrificial layer film outside the modified second photoresist pattern area by etching to form a sacrificial layer structure, the sacrificial layer structure including a tympanic membrane area and an outwardly extending structure, the edge profile of the sacrificial layer structure being consistent with the profile of the modified second photoresist pattern;

[0015] The top electrode and the second feedback circuit structure are prepared, including:

[0016] A top electrode and a second feedback circuit structure are formed on the first surface of the sacrificial layer structure and the first surface of the substrate, wherein the top electrode includes a tympanic membrane portion and a support portion, and the contour of the edge of the tympanic membrane portion of the top electrode is consistent with the contour of the edge of the tympanic membrane portion of the sacrificial layer structure;

[0017] Preparation of suspended structures, including:

[0018] forming a release window structure on a first surface of the top electrode; and

[0019] The sacrificial layer structure is etched to completely etch the sacrificial layer film of the outwardly extending structure and the sacrificial layer film of the eardrum area at the same time, wherein the sacrificial layer film of the eardrum area is etched through the release window structure, so that the eardrum area portion of the top electrode forms a suspended structure.

[0020] According to some embodiments of the present application, a first photoresist pattern formed on a first surface of a substrate using a first photoresist includes:

[0021] forming a first photoresist on a first surface of the substrate;

[0022] Exposing and developing the first photoresist to form a first photoresist pattern of a preset bottom electrode, a first feedback circuit and an overlay mark structure;

[0023] Forming a bottom electrode, a first feedback circuit, and an overlay mark structure on a first surface of a substrate by a first photoresist pattern includes:

[0024] Depositing a first superconducting thin film based on the first photoresist pattern, the first superconducting thin film being formed on a first surface of the remaining first photoresist and a first surface of the substrate; and

[0025] The first superconducting film formed on the first surface of the remaining first photoresist is stripped off, and the remaining first photoresist is removed to form a bottom electrode, a first feedback line, and an overlay mark structure.

[0026] According to some embodiments of the present application, performing a reflow process on a substrate having a second photoresist pattern formed thereon to obtain a modified second photoresist pattern having a uniform arc-shaped edge includes:

[0027] placing the substrate having the second photoresist pattern formed thereon on a hot plate having a first preset temperature;

[0028] heating the hot plate so that the hot plate is heated to a second preset temperature greater than the first preset temperature within a first preset time,

[0029] The first preset temperature is 110-115°C, the second preset temperature is 140-150°C, and the first preset time is 4-7 minutes.

[0030] According to some embodiments of the present application, removing the sacrificial layer film outside the modified second photoresist pattern area by etching to form a sacrificial layer structure includes: etching the second photoresist pattern of the substrate processed by the reflow process twice,

[0031] The first etching uses O2, and the second etching uses CF4.

[0032] According to some embodiments of the present application, forming a top electrode and a second feedback circuit structure on a first surface of the sacrificial layer structure and a first surface of the substrate includes:

[0033] forming a third photoresist on the first surface of the sacrificial layer structure and the first surface of the substrate;

[0034] Performing alignment overlay exposure and development on the third photoresist to form a third photoresist pattern of a preset top electrode and a second feedback circuit structure;

[0035] depositing a second superconducting thin film based on the third photoresist pattern, the second superconducting thin film being formed on a first surface of the remaining third photoresist, a first surface of the substrate, and a first surface of the sacrificial layer structure; and

[0036] The second superconducting film formed on the first surface of the remaining third photoresist is stripped off, and the remaining third photoresist is removed to form a top electrode and a second feedback line structure.

[0037] According to some embodiments of the present application, forming a release window structure on a first surface of the top electrode includes:

[0038] forming a fourth photoresist on the first surface of the substrate having the top electrode and the second feedback circuit structure formed thereon;

[0039] Performing alignment overlay exposure and development on the fourth photoresist to form a fourth photoresist pattern having a preset release window structure;

[0040] Etching the second superconducting thin film through the preset release window structure of the fourth photoresist pattern region to expose the sacrificial layer structure through the release window structure; and

[0041] The remaining fourth photoresist is removed to form a release window structure.

[0042] According to some embodiments of the present application, before the sacrificial layer film in the eardrum area is removed by etching through the release window structure so that the top electrode in the eardrum area forms a suspended structure, it also includes placing the substrate formed with the release window structure on a hot plate with a third preset temperature and baking it for a second preset time, the third preset temperature is 150-180°C, and the second preset time is 10-20min.

[0043] According to some embodiments of the present application, the method further includes: removing residual photoresist in the final stage of preparing the bottom electrode, the first feedback circuit and the overlay mark structure, preparing the sacrificial layer structure, preparing the top electrode and the second feedback circuit structure, and preparing the suspended structure;

[0044] Removing the residual photoresist includes: soaking the substrate in methyl pyrrolidone, then transferring it to isopropanol for soaking, then blowing it dry with high-purity nitrogen, and finally treating it with oxygen plasma to remove the residual photoresist.

[0045] According to some embodiments of the present application, the process steps of etching the sacrificial layer structure and completely etching the sacrificial layer film of the outwardly extending structure and the sacrificial layer film of the tympanic membrane area at the same time include:

[0046] Step 1, etching process parameters are: SF6 flow rate is 50sccm, O2 flow rate is 5sccm, process pressure is 20Pa, RF power is 80W, and process time is 1min;

[0047] Step 2, etching process parameters are: Ar flow rate is 30sccm, O2 flow rate is 10sccm, process pressure is 25Pa, RF power is 0W, and process time is 30s;

[0048] Repeat steps 1 and 2 for 3-8 cycles.

[0049] According to some embodiments of the present application, the release window structure is periodically arranged in basic structural units at equal intervals in the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area;

[0050] The diameter or side length of the basic structural unit is 2-3μm.

[0051] According to some embodiments of the present application, the bottom electrode is circular with a first diameter;

[0052] The tympanic membrane region of the sacrificial layer structure is circular with a second diameter;

[0053] The top electrode is circular with a third diameter, wherein the first diameter is smaller than the second diameter, and the second diameter is smaller than the third diameter,

[0054] The difference between the second diameter and the first diameter is ≥12 μm.

[0055] According to some embodiments of the present application, the bottom electrode is located at the center of the substrate on the first surface of the substrate; the bottom electrode is circular; the first feedback line extends outward from the bottom electrode and has a T-shaped structure; the overlay mark structure is located at the edge of the substrate;

[0056] The sacrificial layer structure includes a tympanic membrane area and an outward extending structure; wherein the tympanic membrane area is circular and aligned with the center of the bottom electrode; one end of the outward extending structure is connected to the tympanic membrane area, and the other end extends outward to form a T-shaped structure, and the outward extending structure overlaps with the first feedback circuit and completely covers the first feedback circuit; wherein the sides of the tympanic membrane area and the outward extending structure are in a uniform arc shape.

[0057] According to another aspect of the present application, a mechanical oscillator quantum device based on a superconducting film is also provided, which is prepared by the above-mentioned preparation method, and the mechanical oscillator quantum device includes:

[0058] substrate;

[0059] The bottom electrode, the first feedback circuit and the overlay mark structure are located on the first surface of the substrate; wherein the bottom electrode is located in the center of the substrate; the bottom electrode is circular; the first feedback circuit extends outward from the bottom electrode and forms a T-shaped structure; the overlay mark structure is located at the edge of the substrate;

[0060] The top electrode and the second feedback circuit structure are located on the first surface of the substrate; wherein the top electrode is circular and aligned with the center of the bottom electrode; the second feedback circuit is formed by extending from the top electrode in the opposite direction of the first feedback circuit and is in a T-shaped structure;

[0061] Wherein, the top electrode comprises:

[0062] The tympanic membrane area portion is located at the center of the top electrode and is opposite to the bottom electrode, and a suspended structure is provided between the tympanic membrane area portion and the bottom electrode;

[0063] A support portion, the support portion is disposed on the first surface of the base sheet and supports the eardrum region portion, the support portion being formed integrally with the eardrum region portion;

[0064] A release window structure is located at the center of an annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area; wherein the release window structure is periodically arranged at equal intervals in a basic structural unit.

[0065] Compared with the prior art, this application has at least the following beneficial effects:

[0066] The present application provides a mechanical oscillator quantum device based on a superconducting film. The device is provided with a release window structure periodically arranged with equal intervals as a basic structural unit at the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area. When the sacrificial layer film of the tympanic membrane area is etched through the release window structure, the suspended structure formed by the superconducting film in the tympanic membrane area presents a uniform morphology, so that the device has good stability.

[0067] The present application provides a method for preparing a mechanical oscillator quantum device based on a superconducting film, wherein the morphology of the photoresist is modified through a reflow process step, and the edge sidewall of the prepared sacrificial layer structure is uniformly arc-shaped, so that the top electrode composed of the grown superconducting film material is not prone to produce steep steps. At the same time, after the sacrificial layer structure is released, the top electrode in the tympanic membrane area will not collapse.

[0068] The method for preparing a mechanical oscillator quantum device based on a superconducting film of the present application also bakes the substrate before releasing the sacrificial layer structure, and controls the baking temperature and baking time of the baking hot plate to quantitatively control the size of the gap between the tympanic membrane area of ​​the top electrode and the bottom electrode (i.e., the thickness of the suspended structure), thereby obtaining a quantum device with stable performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 It is a schematic plan view of the structure of the eardrum mechanical vibrator device in which the sacrificial layer structure is not etched in the prior art.

[0070] Figure 2 This is a schematic diagram of the cross-section of the structure of the eardrum mechanical vibrator device in the prior art (a: sacrificial layer before etching; b: sacrificial layer after etching).

[0071] Figure 3 This is a morphological diagram of the tympanic membrane mechanical vibrator device after release in the prior art.

[0072] Figure 4 It is a schematic diagram of the process flow of preparing the bottom electrode, the first feedback circuit and the overlay mark structure of the exemplary embodiment of the present application.

[0073] Figure 5 1 is a plan view of a bottom electrode, a first feedback line, and an overlay mark structure according to an exemplary embodiment of the present application.

[0074] Figure 6This is a schematic diagram of the process flow for preparing a sacrificial layer structure according to an exemplary embodiment of the present application.

[0075] Figure 7 This is a plan view of the device structure after the sacrificial layer structure of the exemplary embodiment of the present application is prepared.

[0076] Figure 8 The following are scanning electron microscope images of the sacrificial layer after the reactive ion etching (RIE) process according to an exemplary embodiment of the present application (a is a cross-sectional view, b is a top view).

[0077] Fig. 9 A schematic diagram of the process flow for preparing the top electrode and the second feedback circuit structure according to an exemplary embodiment of the present application.

[0078] Fig.10 This is a plan view of the device structure after the top electrode and the second feedback line structure of the exemplary embodiment of the present application are prepared.

[0079] Fig.11 This is a schematic diagram of the process flow for preparing the release window structure according to an exemplary embodiment of the present application.

[0080] Fig.12 This is a plan view of the device structure after the release window structure of the exemplary embodiment of the present application is prepared.

[0081] Fig.13 This is a plan view of the device structure after the release window structure of another embodiment of the present application is prepared.

[0082] Fig.14 This is a flowchart of the sacrificial layer structure etching process according to an exemplary embodiment of the present application.

[0083] Fig.15 This is a schematic plan view of the sacrificial layer structure after etching according to an exemplary embodiment of the present application.

[0084] Fig.16 This is a schematic cross-sectional view of the eardrum mechanical oscillator quantum device according to an exemplary embodiment of the present application (a the sacrificial layer is not etched, b the sacrificial layer is etched).

[0085] Fig.17 This is a laser 3D microscope morphology image of the eardrum mechanical vibrator device after release according to the exemplary embodiment of the present application.

[0086] Fig.18 This is a schematic diagram of placing the eardrum mechanical vibrator device according to an exemplary embodiment of the present application in a 3D cavity. DETAILED DESCRIPTION

[0087] The technical solution of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0088] It is particularly important to point out that similar substitutions and modifications made to the present application are obvious to those skilled in the art, and they are all deemed to be included in the present application. Relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present application to implement and apply the technology of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments.

[0089] If no specific conditions are specified in this application, the preparation shall be carried out under conventional conditions or the conditions recommended by the manufacturer. The raw materials or excipients used, as well as the reagents or instruments used, for which the manufacturers are not specified, are all conventional products that can be obtained commercially.

[0090] The application is described in detail below.

[0091] At present, the process flow of preparing tympanic membrane mechanical oscillator quantum devices in the existing technology is:

[0092] Preparation of the first device layer: on a preset substrate, a layer of superconducting thin film material is deposited by sputtering or evaporation, a layer of photoresist is spin-coated on the thin film material, and a first device layer pattern is formed after exposure and development, and then the portion not covered by the photoresist is removed by plasma dry etching or corrosive liquid wet etching, so that the design pattern is transferred to the thin film material to form the first device layer;

[0093] Preparation of the second device layer: On the first device layer, a layer of dielectric thin film material is deposited by chemical vapor deposition as a sacrificial layer material, such as silicon oxide, amorphous silicon, etc., and then a layer of photoresist is spin-coated on the sacrificial layer material, and a second device layer pattern is formed after exposure and development, and then the portion not covered by the photoresist is removed by plasma dry etching technology, so that the design pattern is transferred to the sacrificial layer to form the second device layer;

[0094] Preparation of the third device layer (tympanic membrane layer): on the second device layer, a layer of superconducting thin film material is deposited by sputtering or evaporation, a layer of photoresist is spin-coated on the thin film material, and the third device layer pattern is formed after exposure and development. The portion not covered by the photoresist is then removed by plasma dry etching or corrosive liquid wet etching, so that the design pattern is transferred to the thin film material to form the third device layer; finally, the second device layer is removed by plasma etching technology or F-containing gas vapor etching, so that the third device layer is suspended above the first device layer to form a tympanic membrane mechanical oscillator quantum device structure, thereby preparing a tympanic membrane oscillator quantum device.

[0095] In the above-mentioned prior art preparation process, during the process of preparing the middle sacrificial layer, four corners are exposed at the edge of the sacrificial layer film in the eardrum area, and the four corners are not covered by the upper superconducting film layer, thereby reserving four release openings on the side, such as Figure 1 The figure shows a schematic diagram of the planar structure of the current eardrum mechanical vibrator device. Figure 2 (a) Yes Figure 1 Cross-sectional view along AA'. Figure 2 As shown in (b), it can be seen that when the sacrificial layer in the middle of the tympanic membrane area is completely etched, the top electrode (i.e., the top superconducting film layer) forms a suspended structure. In this way, at the step of the top superconducting film, due to the influence of the relatively steep step, the mechanical strength of the film at the step is very weak, which will cause the top superconducting film layer to collapse due to insufficient mechanical strength at the step. In addition, this method of reserving a release port on the side is to gradually etch the middle sacrificial layer toward the center area from four specific side directions, which will cause the top superconducting film layer to form an uneven suspended structure morphology, such as Figure 3 As shown, this ultimately leads to poor stability of the fabricated device.

[0096] In view of the above problems in the art, the present application provides a superconducting film-based mechanical oscillator quantum device and a preparation method thereof, which improves the stability of the device by adding a release window in the tympanic membrane area of ​​the top electrode, adding a reflow process, and a baking process.

[0097] In some examples, the method for preparing a superconducting film-based mechanical oscillator quantum device of the present application includes:

[0098] The bottom electrode, the first feedback circuit and the overlay mark structure are prepared, including:

[0099] Using a first photoresist to form a first photoresist pattern on a first surface of the substrate; forming a bottom electrode, a first feedback circuit and an overlay mark structure on the first surface of the substrate through the first photoresist pattern;

[0100] Preparation of sacrificial layer structure, including:

[0101] Growing a sacrificial layer film on the first surface side of the substrate to cover the bottom electrode, the first feedback circuit and the overlay mark structure;

[0102] Using a second photoresist to form a second photoresist pattern on a predetermined area on the surface of the sacrificial layer film, the second photoresist pattern is used to form a preset sacrificial layer structure;

[0103] Performing a reflow process on the substrate formed with the second photoresist pattern to obtain a corrected second photoresist pattern having a uniform arc-shaped edge; and

[0104] Removing the sacrificial layer film outside the modified second photoresist pattern area by etching to form a sacrificial layer structure, the sacrificial layer structure including a tympanic membrane area and an outwardly extending structure (i.e., an area covering the first feedback circuit), and the contour of the edge of the sacrificial layer structure is consistent with the contour of the modified second photoresist pattern;

[0105] The top electrode and the second feedback circuit structure are prepared, including:

[0106] A top electrode and a second feedback circuit structure are formed on the first surface of the sacrificial layer structure and the first surface of the substrate, wherein the top electrode includes a tympanic membrane portion and a support portion, and the contour of the edge of the tympanic membrane portion of the top electrode is consistent with the contour of the edge of the tympanic membrane portion of the sacrificial layer structure;

[0107] Preparation of suspended structures, including:

[0108] forming a release window structure on a first surface of the top electrode; and

[0109] The sacrificial layer structure is etched to completely etch the sacrificial layer film of the outwardly extending structure and the sacrificial layer film of the eardrum area at the same time, wherein the sacrificial layer film of the eardrum area is etched through the release window structure, so that the eardrum area portion of the top electrode forms a suspended structure.

[0110] In some examples, forming a first photoresist pattern on a first surface of a substrate using a first photoresist includes:

[0111] forming a first photoresist on a first surface of the substrate;

[0112] Exposing and developing the first photoresist to form a first photoresist pattern of a preset bottom electrode, a first feedback circuit and an overlay mark structure;

[0113] Forming a bottom electrode, a first feedback circuit, and an overlay mark structure on a first surface of a substrate by a first photoresist pattern includes:

[0114] Depositing a first superconducting thin film based on the first photoresist pattern, the first superconducting thin film being formed on a first surface of the remaining first photoresist and a first surface of the substrate; and

[0115] The first superconducting film formed on the first surface of the remaining first photoresist (ie, the first superconducting film outside the first photoresist pattern area) is stripped and the remaining first photoresist is removed to form a bottom electrode, a first feedback circuit, and an overlay mark structure.

[0116] In some examples, performing a reflow process on the substrate having the second photoresist pattern formed thereon to obtain a modified second photoresist pattern having a uniform arc-shaped edge includes:

[0117] placing the substrate having the second photoresist pattern formed thereon on a hot plate having a first preset temperature;

[0118] heating the hot plate so that the hot plate is heated to a second preset temperature greater than the first preset temperature within a first preset time,

[0119] The first preset temperature is 110-115°C, the second preset temperature is 140-150°C, and the first preset time is 4-7 minutes.

[0120] In some examples, removing the sacrificial layer film outside the modified second photoresist pattern area by etching to form a sacrificial layer structure includes: etching the second photoresist pattern of the substrate processed by the reflow process twice, wherein the first etching uses O2 and the second etching uses CF4.

[0121] In some embodiments of the present application, the first etching process parameters are: O2 flow rate 50sccm, process pressure 5Pa, RF power 50W, process time 20s; and the second etching process parameters are: CF4 flow rate 30sccm, process pressure 2Pa, RF power 60W, process time 200s. The process parameters are generally determined according to the size of the sacrificial layer structure, and the parameters that can achieve the effect of the present application are within the scope of the present application.

[0122] In some examples, forming a top electrode and a second feedback line structure on a first surface of the sacrificial layer structure and a first surface of the substrate includes:

[0123] forming a third photoresist on the first surface of the sacrificial layer structure and the first surface of the substrate;

[0124] Performing alignment overlay exposure and development on the third photoresist to form a third photoresist pattern of a preset top electrode and a second feedback circuit structure;

[0125] depositing a second superconducting thin film based on the third photoresist pattern, the second superconducting thin film being formed on a first surface of the remaining third photoresist, a first surface of the substrate, and a first surface of the sacrificial layer structure; and

[0126] The second superconducting film formed on the first surface of the remaining third photoresist (ie, the second superconducting film outside the third photoresist pattern region) is stripped off, and the remaining third photoresist is removed to form a top electrode and a second feedback line structure.

[0127] The first superconducting film and the second superconducting film of the present application may be films made of any superconducting material such as aluminum film, tantalum film, niobium film, etc.

[0128] In some examples, forming a release window structure on the first surface of the top electrode includes:

[0129] forming a fourth photoresist on the first surface of the substrate having the top electrode and the second feedback circuit structure formed thereon;

[0130] Performing alignment overlay exposure and development on the fourth photoresist to form a fourth photoresist pattern having a preset release window structure;

[0131] Etching the second superconducting thin film through the preset release window structure of the fourth photoresist pattern region to expose the sacrificial layer structure through the release window structure; and

[0132] The remaining fourth photoresist is removed to form a release window structure.

[0133] In some instances, before the sacrificial layer film in the eardrum area is removed by etching through the release window structure so that the eardrum area portion of the top electrode forms a suspended structure, the substrate formed with the release window structure is also included in the step of placing the substrate on a hot plate with a third preset temperature and baking it for a second preset time, wherein the third preset temperature is 150-180°C, and the second preset time is 10-20 minutes.

[0134] In some examples, the method further includes: removing residual photoresist in the final stage of preparing the bottom electrode, the first feedback line and the overlay mark structure, preparing the sacrificial layer structure, preparing the top electrode and the second feedback line structure, and preparing the suspended structure;

[0135] Removing the residual photoresist includes: soaking the substrate in methyl pyrrolidone, then transferring it to isopropanol for soaking, then blowing it dry with high-purity nitrogen, and finally treating it with oxygen plasma to remove the residual photoresist.

[0136] In some examples, the process steps of etching the sacrificial layer structure and completely etching the sacrificial layer film of the outwardly extending structure (i.e., covering the first feedback circuit area) and the sacrificial layer film of the eardrum area at the same time include:

[0137] Step 1, etching process parameters are: SF6 flow rate is 50sccm, O2 flow rate is 5sccm, process pressure is 20Pa, RF power is 80W, and process time is 1min;

[0138] Step 2, etching process parameters are: Ar flow rate is 30sccm, O2 flow rate is 10sccm, process pressure is 25Pa, RF power is 0W, and process time is 30s;

[0139] Repeat steps 1 and 2 for 3-8 cycles.

[0140] In some examples, the release window structures are periodically arranged in basic structural units at equal intervals in the center of an annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area;

[0141] The diameter or side length of the basic structural unit is 2-3μm.

[0142] In some examples, the bottom electrode is circular with a first diameter;

[0143] The tympanic membrane region of the sacrificial layer structure is circular with a second diameter;

[0144] The top electrode is circular with a third diameter, wherein the first diameter is smaller than the second diameter, and the second diameter is smaller than the third diameter,

[0145] The difference between the second diameter and the first diameter is ≥12 μm.

[0146] In some embodiments, the bottom electrode is located at the center of the substrate on the first surface of the substrate; the bottom electrode is circular; the first feedback line extends outward from the bottom electrode and has a T-shaped structure; the overlay mark structure is located at the edge of the substrate;

[0147] The sacrificial layer structure also includes a tympanic membrane area and an outward extending structure; wherein the tympanic membrane area is circular and aligned with the center of the bottom electrode; one end of the outward extending structure is connected to the tympanic membrane area, and the other end extends outward to form a T-shaped structure, and the outward extending structure overlaps with the first feedback circuit and completely covers the first feedback circuit; wherein the sides of the tympanic membrane area and the outward extending structure are in a uniform arc shape.

[0148] According to another aspect of the present application, a mechanical oscillator quantum device based on a superconducting film is also provided, which is prepared by the above-mentioned preparation method, and the mechanical oscillator quantum device includes:

[0149] substrate;

[0150] The bottom electrode, the first feedback circuit and the overlay mark structure are located on the first surface of the substrate; wherein the bottom electrode is located in the center of the substrate; the bottom electrode is circular; the first feedback circuit extends outward from the bottom electrode and forms a T-shaped structure; the overlay mark structure is located at the edge of the substrate;

[0151] A top electrode and a second feedback circuit structure are located on a first surface of the substrate; wherein the top electrode is circular and aligned with the center of the bottom electrode; the second feedback circuit is formed by extending from the top electrode in the opposite direction of the first feedback circuit and is in a T-shaped structure;

[0152] Wherein, the top electrode comprises:

[0153] The eardrum area portion is located at the center of the top electrode and is connected to the bottom electrode, and a suspended structure is provided between the eardrum area portion and the bottom electrode;

[0154] a supporting portion, the supporting portion being disposed on the first surface of the substrate and supporting the eardrum region portion, the supporting portion being integrally formed with the eardrum region portion;

[0155] A release window structure, wherein the release window structure is located at the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area; wherein the release window structure is periodically arranged at equal intervals in a basic structural unit.

[0156] The present application optimizes the process to solve the problem of collapse caused by insufficient mechanical strength at the steps in the prior art. When preparing the sacrificial layer, a reflow process is used for the photoresist after exposure and development, and the morphology of the photoresist is corrected so that the side steps form a gentle slope (uniform arc shape). In this way, after etching, a gentle slope with a smaller angle of the side steps of the sacrificial layer structure is achieved. When growing the top electrode composed of superconducting material, it is easier to cross the steps, which can avoid the problem of collapse of the tympanic membrane area of ​​the top electrode after release due to the presence of steep steps.

[0157] The present application also improves the structural design to address the problem that the suspended structure in the tympanic membrane area of ​​the top electrode formed after the middle sacrificial layer structure is etched is not uniform in morphology. In the tympanic membrane area, the three layers of material are designed into concentric circles, and the radius gradually increases in the order of the bottom electrode, the tympanic membrane area of ​​the sacrificial layer structure, and the top electrode. After the top electrode is prepared, the middle sacrificial layer structure is not exposed on the side. On this basis, an exposure / development step is added, and release windows are periodically arranged with uniform spacing around the annular area formed by concentric circles of different radii of the sacrificial layer structure and the top electrode. Then, after exposure / development / baking, the upper superconducting thin film material in the release window area is wet-etched or dry-etched until the middle sacrificial layer structure is completely exposed. Then, plasma dry etching or HF vapor or XeF2 vapor etching is used to remove the middle sacrificial layer structure through the release window to obtain a suspended structure in the tympanic membrane area of ​​the top electrode with uniform force and shape.

[0158] The present application also bakes the substrate before etching the sacrificial layer, and controls the baking temperature and baking time of the baking hot plate to quantitatively control the gap between the tympanic membrane area of ​​the top electrode and the bottom electrode to achieve the desired gap value, thereby obtaining a quantum device with stable performance.

[0159] The technical solution of the present application is further described below in conjunction with specific embodiments.

[0160] Example 1

[0161] A single-sided polished sapphire substrate with a thickness of 500 μm is cleaned with acetone and isopropanol, and then a double-layer photoresist is spin-coated on the polished surface. The lower layer photoresist LOR10B was coated with a rotation speed of 3000 rpm for 60 seconds, and then the substrate coated with the lower layer photoresist LOR10B was placed on a hot plate for baking at a temperature of 200°C for 10 minutes; after cooling to room temperature, the upper layer photoresist S1813 was spin-coated on the surface of the lower layer photoresist LOR10B, and the rotation speed was 3000 rpm for 60 seconds, and then the substrate coated with the lower layer photoresist LOR10B and the upper layer photoresist S1813 was placed on a hot plate for baking at a temperature of 115°C for 2 minutes, and the substrate coated with the lower layer photoresist LOR10B and the upper layer photoresist S1813 was exposed using a laser direct writing system, and the exposure parameters were: focus (Focus) was about -20%, light intensity (Intensity) was about 30%, and laser power (Laser The power is about 70mW, the filter coefficient is about 12.5%, and then developed with MIF319 developer for 45s to form a photoresist pattern of a preset bottom electrode, a first feedback circuit, and an overlay mark structure. The preset bottom electrode is a circle with a diameter of 16μm.

[0162] O2 plasma is used to treat the areas not covered by the photoresist after exposure and development to remove any residual photoresist. In the areas not covered by the photoresist and other areas, sputtering or evaporation techniques are used to deposit 30nm thick aluminum superconducting thin film materials.

[0163] The substrate is immersed in an organic solvent NMP at room temperature for more than 12 hours, and the aluminum superconducting film material in the unexposed area is stripped to form a bottom electrode, a first feedback circuit, and an overlay mark photoresist pattern. The substrate is immersed in isopropanol for more than 10 minutes to remove the NMP organic matter on the surface. Then an O2 plasma process is used, with an O2 flow rate of 50sccm, a process pressure of 10Pa, a radio frequency power of 100W, and a process time of 5min, to process the area of ​​the substrate where the superconducting film material is evaporated and the area of ​​the substrate that is not evaporated, to remove the photoresist that may remain, and to obtain a bottom electrode, a first feedback circuit, and an overlay mark structure.

[0164] On the substrate with the bottom electrode, the first feedback circuit and the overlay mark structure prepared, a 100nm thick amorphous silicon film is grown by plasma chemical vapor deposition (PECVD). The photoresist S1805 is spin-coated on the surface of the amorphous silicon film, the rotation speed is 3000rpm, the time is 60s, and then the substrate with the photoresist S1805 spin-coated is placed on a hot plate for baking, the baking temperature is 115℃, the time is 2min, and the substrate with the photoresist S1805 spin-coated is aligned and overlaid by a laser direct writing system. The exposure parameters are: focus (Focus) is about 40%, light intensity (Intensity) is about 55%, laser power (Laserpower) is about 100mW, and filter coefficient (Filter) is about 5%. Then, it is developed with MIF319 developer for 15s to form a circular photoresist pattern with a preset sacrificial layer structure with a diameter of 30μm.

[0165] The substrate with the photoresist pattern of the preset sacrificial layer structure is placed on a hot plate for a reflow process: the initial temperature of the hot plate is set to 115°C, the end temperature is set to 140°C, and the baking time is set to 5 minutes. After the photoresist pattern of the preset sacrificial layer structure undergoes the reflow process, the edge sidewall forms a uniform arc shape.

[0166] The substrate after the reflow process is subjected to reactive ion etching (RIE). The etching is carried out in two steps. The parameters for step 1 are: O2 flow rate is 50sccm, process pressure is 5Pa, RF power is 50W, and process time is 20s. The parameters for step 2 are: CF4 flow rate is 30sccm, process pressure is 2Pa, RF power is 60W, and process time is 200s. Figure 8 This is a scanning electron microscope image of the morphology after RIE etching.

[0167] The substrate after RIE etching is immersed in NMP for more than 2 hours, and then transferred to isopropanol and immersed for 30 minutes to remove the residual photoresist after etching, forming a sacrificial layer structure (such as Figure 7 as shown).

[0168] A double-layer photoresist is spin-coated on the substrate with the sacrificial layer structure prepared. The lower layer photoresist LOR10B was coated with a rotation speed of 3000 rpm for 60 seconds, and then the substrate coated with the lower layer photoresist LOR10B was placed on a hot plate for baking at a temperature of 200°C for 10 minutes; after cooling to room temperature, the upper layer photoresist S1813 was spin-coated on the surface of the lower layer photoresist LOR10B, and the rotation speed was 3000 rpm for 60 seconds, and then the substrate coated with the lower layer photoresist LOR10B and the upper layer photoresist S1813 was placed on a hot plate for baking at a temperature of 115°C for 2 minutes, and then the laser direct writing system was used to align and overlay the substrates coated with the lower layer photoresist LOR10B and the upper layer photoresist S1813, and the exposure parameters were: focus (Focus) was about -20%, light intensity (Intensity) was about 30%, and laser power (Laser The power is about 70mW, the filter coefficient is about 12.5%, and then developed with MIF319 developer for 45s to form a preset photoresist pattern of the top electrode and the second feedback circuit structure.

[0169] The top electrode and feedback circuit structure are as follows Fig.10 As shown, the preset top electrode is a circle with a diameter of 40 μm. An O2 plasma process is used with an O2 flow rate of 50 sccm, a process pressure of 10 Pa, a RF power of 100 W, and a process time of 5 min to process the area not covered by the photoresist after exposure and development to remove any residual photoresist.

[0170] In the area not covered by the photoresist and in the area outside the area, a layer of aluminum superconducting thin film material with a thickness of 120nm is deposited by sputtering or evaporation. The substrate is immersed in an organic solvent NMP at room temperature for more than 12 hours, and the superconducting thin film material evaporated in the unexposed area is peeled off to form a top electrode and a second feedback line structure pattern. The substrate is immersed in isopropanol for more than 10 minutes to remove the NMP organic matter on the surface. The area where the superconducting thin film material is evaporated and the area of ​​the substrate that is not evaporated are treated with O2 plasma again to remove any residual photoresist and form a top electrode and a second feedback line structure.

[0171] On the substrate formed with the top electrode and feedback circuit structure, the photoresist S1813 was spin-coated with a thickness of 1.4 μm, and baked on a preset 115°C hot plate for 2 minutes. The substrate with the spin-coated photoresist S1813 was aligned and exposed using a laser direct writing system. The exposure parameters were: focus (Focus) of about -20%, light intensity (Intensity) of about 30%, laser power (Laserpower) of about 70 mW, and filter coefficient (Filter) of about 12.5%. Then, it was developed with MIF319 developer for 35 seconds to form a preset circular release window structure photoresist pattern (such as Fig.12 As shown in FIG. 1 ), the electrodes are periodically arranged at equal intervals at the center of the annular area formed by the edge of the bottom electrode and the edge of the tympanic membrane area.

[0172] Electronic grade aluminum film etching liquid was used for wet etching, model LCKS-3, and the etching time was 10 minutes. The sacrificial layer structure in the release window area was completely exposed. After etching, the substrate was immersed in NMP for more than 2 hours, transferred to isopropanol and immersed for 30 minutes to remove the residual photoresist after etching, forming a circular release window structure.

[0173] The substrate with the release window structure is placed on a hot plate at 150°C for baking for 10 minutes. A reactive ion etching system is used to etch the sacrificial layer structure of the outwardly extending structure, and at the same time, the sacrificial layer structure of the eardrum area is etched through the release window structure. The etching is carried out in two steps. The parameters of step 1 are: SF6 flow rate 50sccm, O2 flow rate 5sccm, process pressure 20Pa, RF power 80W, and process time 60s. The parameters of step 2 process are: Ar flow rate 30sccm, O2 flow rate 10sccm, process pressure 25Pa, RF power 0W, and process time 30s. Steps 1 and 2 are run for 3 cycles, so that the top electrode in the eardrum area forms a suspended structure, and the mechanical oscillator quantum device based on superconducting film of the present application is obtained.

[0174] Example 2

[0175] The preparation process is basically the same as that of Example 1, except that:

[0176] The preset bottom electrode is circular in shape with a diameter of 12 μm; the thickness of the aluminum superconducting thin film material of the bottom electrode is 50 nm.

[0177] The preset sacrificial layer structure is circular with a diameter of 25 μm; the amorphous silicon film has a thickness of 130 nm.

[0178] The preset top electrode is circular in shape with a diameter of 40 μm. The thickness of the aluminum superconducting thin film material of the top electrode is 150 nm.

[0179] The photoresist pattern of the preset release window structure is a square (such as Fig.13 as shown).

[0180] The substrate with the release window structure was placed on a hot plate at 150° C. and baked for 20 minutes.

[0181] After 5 cycles, the mechanical oscillator quantum device based on superconducting film of the present application is obtained.

[0182] Comparative Example 1

[0183] The preparation process is basically the same as that of Example 1, except that:

[0184] The substrate forming the release window structure is not baked, and a reactive ion etching system is directly used to release the middle sacrificial layer.

[0185] Comparative Example 2

[0186] The preparation process is basically the same as that of Example 1, except that:

[0187] The substrate with the release window structure was placed on a hot plate at 175° C. and baked for 10 minutes.

[0188] Experimental example

[0189] A 3D laser microscope was used to test the gap value between the top electrode and the bottom electrode after the sacrificial layer was released at different baking temperatures and baking times. The gap value between the bottom electrode and the top electrode of the substrates of the embodiment and the comparative example after baking was tested, and the results are shown in the following table:

[0190]

[0191] According to the data in the above table, the present application quantitatively controls the gap between the tympanic membrane area of ​​the top electrode and the bottom electrode by baking the substrate before etching the sacrificial layer structure to obtain the desired gap value.

[0192] according to Fig.17 It can be seen that the tympanic membrane mechanical oscillator quantum device of the present application has a morphology after the sacrificial layer is etched, and the tympanic membrane area of ​​the top electrode is still a basically regular circle, and the device has good stability.

[0193] Application Examples

[0194] The mechanical oscillator quantum device based on superconducting film prepared in Example 2 of the present application is placed in a 3D cavity made of aluminum, and the 3D cavity is placed in a dilution refrigerator and cooled to 20mK. At the input signal port 1, the 3D cavity is driven by a fully attenuated input signal, and at the output signal port, the 3D cavity frequency ω is obtained. c ; Then input a strong driving microwave signal ω at the input signal port 1 c -ωm , where ω m The frequency of the mechanical oscillator in the tympanic membrane area, at this time the cavity frequency ω c Photomechanically induced transparency will occur nearby, and through this method, the frequency of the mechanical oscillator in the eardrum area can be found.

[0195] Then input the red sideband pump signal ω at input signal port 1. b , the system can generate a photon and annihilate a phonon. The photon dissipates into the environment through the 3D cavity. This process is continuous and will eventually make the number of thermal phonons less than 1, which can eventually cool the mechanical oscillator in the eardrum area to the quantum ground state.

[0196] After the mechanical oscillator in the eardrum area is cooled to the ground state, the quantum signal processing chip can be used for the preparation, transmission, storage of quantum states, and as an interface between various types of quantum systems.

[0197] like Fig.18 Shown is a schematic diagram of a tympanic membrane-type mechanical oscillator quantum chip placed in a 3D cavity.

[0198] The figure only shows the lower half of the 3D cavity that carries the chip, and the upper half, which serves as the 3D top cover, is not shown. In actual use, the chip is placed in the lower half of the 3D cavity and fixed, and then the 3D cavity top cover is assembled with it and fastened with bolts.

[0199] The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A method for preparing a mechanical oscillator quantum device based on a superconducting film, characterized in that: include: The bottom electrode, the first feedback circuit and the overlay mark structure are prepared, including: forming a first photoresist pattern on a first surface of the substrate using a first photoresist; forming a bottom electrode, a first feedback circuit, and an overlay mark structure on the first surface of the substrate through the first photoresist pattern; Preparation of sacrificial layer structure, including: Growing a sacrificial layer film on the first surface of the substrate to cover the bottom electrode, the first feedback circuit and the overlay mark structure; Using a second photoresist to form a second photoresist pattern on a predetermined area on the surface of the sacrificial layer film, wherein the second photoresist pattern is used to form a preset sacrificial layer structure; Performing a reflow process on the substrate formed with the second photoresist pattern to obtain a modified second photoresist pattern having a uniform arc-shaped edge; and Removing the sacrificial layer film outside the modified second photoresist pattern area by etching to form the sacrificial layer structure, wherein the sacrificial layer structure includes a tympanic membrane area and an outwardly extending structure, and the contour of the edge of the sacrificial layer structure is consistent with the contour of the modified second photoresist pattern; The top electrode and the second feedback circuit structure are prepared, including: The top electrode and the second feedback circuit structure are formed on the first surface of the sacrificial layer structure and the first surface of the substrate, wherein the top electrode includes a tympanic membrane area portion and a supporting portion, and the contour of the edge of the tympanic membrane area portion of the top electrode is consistent with the contour of the edge of the tympanic membrane area of ​​the sacrificial layer structure; Preparation of suspended structures, including: forming a release window structure on a first surface of the top electrode; and Etching the sacrificial layer structure, and etching the sacrificial layer film of the outwardly extending structure and the sacrificial layer film of the eardrum area completely at the same time; The sacrificial layer film in the eardrum region is etched through the release window structure, so that the eardrum region portion of the top electrode forms a suspended structure; Among them, before the sacrificial layer film of the eardrum area is removed by etching through the release window structure so that the top electrode of the eardrum area forms a suspended structure, it also includes: placing the substrate formed with the release window structure on a hot plate with a third preset temperature and baking it for a second preset time, the third preset temperature is 150°C, and the second preset time is 10 minutes.

2. The preparation method according to claim 1, characterized in that: The forming of a first photoresist pattern on the first surface of the substrate by using the first photoresist comprises: forming the first photoresist on the first surface of the substrate; Exposing and developing the first photoresist to form the first photoresist pattern of the preset bottom electrode, the first feedback circuit and the overlay mark structure; The forming of the bottom electrode, the first feedback circuit and the overlay mark structure on the first surface of the substrate by the first photoresist pattern comprises: depositing a first superconducting thin film based on the first photoresist pattern, wherein the first superconducting thin film is formed on a first surface of the remaining first photoresist and a first surface of the substrate; and The first superconducting film formed on the first surface of the remaining first photoresist is stripped off, and the remaining first photoresist is removed to form the bottom electrode, the first feedback line, and the overlay mark structure.

3. The preparation method according to claim 1, characterized in that: The step of performing a reflow process on the substrate formed with the second photoresist pattern to obtain a corrected second photoresist pattern having a uniform arc-shaped edge comprises: placing the substrate formed with the second photoresist pattern on a hot plate having a first preset temperature; heating the hot plate so that the hot plate is heated to a second preset temperature greater than the first preset temperature within a first preset time, The first preset temperature is 110-115° C., the second preset temperature is 140-150° C., and the first preset time is 4-7 minutes.

4. The preparation method according to claim 1, characterized in that: The step of removing the sacrificial layer film outside the modified second photoresist pattern region by etching to form the sacrificial layer structure comprises: etching the second photoresist pattern of the substrate processed by the reflow process twice, The first etching uses O2, and the second etching uses CF4.

5. The preparation method according to claim 1, characterized in that: Forming a top electrode and a second feedback circuit structure on the first surface of the sacrificial layer structure and the first surface of the substrate comprises: forming a third photoresist on the first surface of the sacrificial layer structure and the first surface of the substrate; Performing alignment overlay exposure and development on the third photoresist to form a third photoresist pattern of a preset top electrode and a second feedback circuit structure; depositing a second superconducting thin film based on the third photoresist pattern, the second superconducting thin film being formed on a first surface of the remaining third photoresist, a first surface of the substrate, and a first surface of the sacrificial layer structure; and The second superconducting thin film formed on the first surface of the remaining third photoresist is stripped, and the remaining third photoresist is removed to form the top electrode and the second feedback line structure.

6. The preparation method according to claim 1, characterized in that: Forming a release window structure on the first surface of the top electrode comprises: forming a fourth photoresist on the first surface of the substrate on which the top electrode and the second feedback line structure are formed; Performing alignment overlay exposure and development on the fourth photoresist to form a fourth photoresist pattern having a preset release window structure; Etching the second superconducting thin film through the preset release window structure of the fourth photoresist pattern region to expose the sacrificial layer structure through the release window structure; and The remaining fourth photoresist is removed to form the release window structure.

7. The preparation method according to any one of claims 1 to 6, characterized in that: Also includes: Removing residual photoresist at the final stage of preparing the bottom electrode, the first feedback circuit and the overlay mark structure, preparing the sacrificial layer structure, preparing the top electrode and the second feedback circuit structure, and preparing the suspended structure; The method for removing the residual photoresist comprises: soaking the substrate in methyl pyrrolidone, then transferring the substrate to isopropanol for soaking, then drying the substrate with high-purity nitrogen, and finally treating the substrate with oxygen plasma to remove the residual photoresist.

8. The preparation method according to claim 1, characterized in that: The process steps of etching the sacrificial layer structure and completely etching the sacrificial layer film of the outwardly extending structure and the sacrificial layer film of the eardrum area at the same time include: Step 1, etching process parameters are: SF6 flow rate is 50sccm, O2 flow rate is 5sccm, process pressure is 20Pa, RF power is 80W, and process time is 1min; Step 2, etching process parameters are: Ar flow rate is 30sccm, O2 flow rate is 10sccm, process pressure is 25Pa, RF power is 0W, and process time is 30s; The steps 1 and 2 are cycled for 3 to 8 times.

9. The preparation method according to claim 1 or 6, characterized in that: The release window structures are periodically arranged in basic structural units at equal intervals at the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area; The diameter or side length of the basic structural unit is 2-3 μm.

10. The preparation method according to claim 1, characterized in that: The bottom electrode is circular with a first diameter; The tympanic membrane region of the sacrificial layer structure is circular with a second diameter; The top electrode is circular with a third diameter; The first diameter is smaller than the second diameter, the second diameter is smaller than the third diameter, and the difference between the second diameter and the first diameter is ≥12 μm.

11. The preparation method according to claim 1 or 10, characterized in that: The bottom electrode is located on the first surface of the substrate at the center of the substrate; the first feedback line extends outward from the bottom electrode and presents a T-shaped structure; the overlay mark structure is located at the edge of the substrate; Among them, the eardrum area of ​​the sacrificial layer structure is aligned with the center of the bottom electrode; one end of the outwardly extending structure of the sacrificial layer structure is connected to the eardrum area, and the other end extends outward to form a T-shaped structure, and the outwardly extending structure overlaps with the first feedback circuit and completely covers the first feedback circuit; wherein the eardrum area and the side edges of the outwardly extending structure are in a uniform arc shape.

12. A mechanical oscillator quantum device based on superconducting film, characterized in that: The mechanical oscillator quantum device is prepared by the preparation method described in any one of claims 1 to 11, comprising: substrate; A bottom electrode, a first feedback circuit and an overlay mark structure are located on the first surface of the substrate; wherein the bottom electrode is located in the center of the substrate; the bottom electrode is circular; the first feedback circuit extends outward from the bottom electrode to form a T-shaped structure; the overlay mark structure is located at the edge of the substrate; A top electrode and a second feedback circuit structure are located on the first surface of the substrate; wherein the top electrode is circular and aligned with the center of the bottom electrode; the second feedback circuit is formed by extending from the top electrode in the opposite direction of the first feedback circuit and is in a T-shaped structure; Wherein, the top electrode comprises: an eardrum region portion, the eardrum region portion being located at the center of the top electrode and opposite to the bottom electrode, and having a suspended structure between the eardrum region portion and the bottom electrode; a supporting portion, the supporting portion being disposed on the first surface of the substrate and supporting the eardrum region portion, the supporting portion being integrally formed with the eardrum region portion; A release window structure, wherein the release window structure is located at the center of the annular area formed between the edge of the bottom electrode and the edge of the tympanic membrane area; wherein the release window structure is periodically arranged at equal intervals in a basic structural unit.

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