Superconducting mechanical oscillator quantum device based on self-alignment processing technology and its preparation method

Abstract

The present application discloses a superconducting mechanical oscillator quantum device based on a self-aligned processing technology and a preparation method thereof, comprising: preparing a bottom electrode and a bottom lead photoresist structure on a first surface of a silicon-based substrate, etching the first surface with the above structure to make it have a groove; growing a first superconducting metal film on the first surface with the groove, stripping off the first superconducting metal film outside the groove area to obtain a bottom electrode and a bottom lead; preparing a sacrificial layer photoresist structure on the first surface where the bottom electrode and the bottom lead are formed, and then etching to make the bottom electrode flush with the first surface of the silicon-based substrate; continuing to grow a sacrificial dielectric, stripping off the sacrificial dielectric outside the sacrificial layer photoresist structure to obtain a sacrificial layer; etching the sacrificial layer to make it flush with the first surface; growing a second superconducting metal film on the first surface with the sacrificial layer; preparing a top electrode, a lead and a top release hole on the surface of the second superconducting metal film; removing the sacrificial layer through the top release hole to obtain a suspended mechanical oscillator.

Description

Technical Field

[0001] The present application relates to the field of micro-nano processing technology, and in particular to a superconducting mechanical oscillator quantum device based on a self-alignment processing technology and a preparation method thereof. Background Art

[0002] Micro-nano mechanical oscillators are widely used in precision measurement, sensors and other fields. They are also considered to have great prospects in the study of macroscopic quantum effects, quantum computing and information. In quantum hybrid systems, micro-nano mechanical oscillators can couple with a variety of common quantum systems such as optics, superconductivity, and spin due to their unique plasticity and good compatibility. They are an important tool for studying basic physics. The quantum cavity optomechanical system constructed by combining micro-nano mechanical oscillators with optical cavities or microwave cavities is an emerging direction in the field of quantum science and technology. Superconducting mechanical oscillators are important devices for quantum cavity optomechanics research and can be applied to the exploration of basic quantum phenomena, quantum precision measurement and other research; at the same time, they are compatible with superconducting quantum computing processors and optical quantum computing processors. Their ultra-high quality factor has become a potential quantum storage for superconducting quantum computing, and is also a medium or quantum interface for hybrid quantum systems. It is an important component for realizing universal quantum computing and quantum networks in the future. Its basic configuration is a bottom electrode, a vacuum gap, and a suspended vibrating top electrode.

[0003] At present, the main technical route for preparing superconducting mechanical oscillators is based on the stacking process of substrate-superconducting metal-sacrificial layer-superconducting metal, and the suspended mechanical oscillator is constructed by releasing the sacrificial layer. The process is simple, but the suspended part is configured in a step-like shape, and the structure is complex and unstable, resulting in low yield; at the same time, the multi-layer steps bring great mechanical losses, making the quality factor of the mechanical oscillator prepared by this method very poor, and it is difficult to meet further experimental needs.

[0004] Chemical mechanical polishing (CMP) combined with ion beam milling (IBE) can be used to prepare a flat superconducting mechanical oscillator, that is, the connection between the suspended area and the supporting area is flat, which can greatly improve its yield and quality. However, the introduction of CMP and IBE poses certain challenges to micro-nano processing technology, resulting in poor uniformity of micro-nano processing and difficulty in controlling the precision of the suspended distance of the suspended structure, and is incompatible with the traditional process method of stacking process that only requires lithography and etching. Summary of the invention

[0005] In order to solve the above-mentioned deficiencies in the art, the present application aims to provide a superconducting mechanical oscillator quantum device based on a self-aligned processing technology and a preparation method thereof. By using the self-aligned processing technology, a flat superconducting mechanical oscillator can be constructed without the need for CMP, which can effectively improve the quality and yield of the mechanical oscillator. At the same time, the processing technology is simple and highly repeatable.

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

[0007] Prepare a bottom electrode and bottom lead photoresist structure on the first surface of the silicon-based substrate by photolithography, then etch the first surface of the silicon-based substrate with the bottom electrode and bottom lead photoresist structure, so that the first surface of the silicon-based substrate has a groove of the bottom electrode and bottom lead photoresist structure; grow a first superconducting metal film on the first surface of the silicon-based substrate with the groove of the bottom electrode and lead photoresist structure, and peel off the first superconducting metal film outside the groove area to obtain the bottom electrode and bottom lead;

[0008] Performing photolithography on the first surface of the silicon-based substrate on which the bottom electrode and the bottom lead are formed to prepare a sacrificial layer photoresist structure, and then etching the area outside the sacrificial layer photoresist structure on the first surface of the silicon-based substrate to make the bottom electrode flush with the first surface of the silicon-based substrate; growing a sacrificial dielectric on the first surface of the silicon-based substrate having the bottom electrode, the bottom lead and the sacrificial layer photoresist structure, and stripping off the sacrificial dielectric outside the sacrificial layer photoresist structure to obtain a sacrificial layer;

[0009] Etching the sacrificial layer so that the sacrificial layer is flush with the first surface of the silicon-based substrate;

[0010] Growing a second superconducting metal film on a first surface of a silicon-based substrate having a sacrificial layer; preparing a top electrode, a lead and a top release hole photoresist structure on the surface of the second superconducting metal film, and etching to obtain the top electrode, the lead and the top release hole; and

[0011] The sacrificial layer is removed through the top release hole to obtain a suspended mechanical oscillator.

[0012] According to some embodiments of the present application, the first superconducting metal film and the second superconducting metal film are grown using electron beam evaporation technology;

[0013] The materials of the first superconducting metal film and the second superconducting metal film include: aluminum, niobium or tantalum.

[0014] According to some embodiments of the present application, the bottom electrode and lead photoresist structure are obtained by ultraviolet lithography or laser direct writing;

[0015] The shapes of the bottom electrode include: circular, square or regular hexagonal;

[0016] The diameter of the bottom electrode or its inscribed circle diameter is 10-50 μm.

[0017] According to some embodiments of the present application, the bottom lead is a microstrip line with a width greater than 2 μm.

[0018] According to some embodiments of the present application, the groove depth is 190-210 nm;

[0019] The first superconducting metal film has a thickness of 90-110 nm; the second superconducting metal film has a thickness of 120-180 nm;

[0020] The difference between the groove depth and the thickness of the first superconducting metal film is 80-120 nm.

[0021] According to some embodiments of the present application, ultraviolet lithography or laser direct writing is used to obtain a sacrificial layer photoresist structure, and electron beam evaporation technology is used to grow the sacrificial layer; the sacrificial dielectric material includes: silicon oxide;

[0022] The thickness of the sacrificial layer is 100nm-150nm.

[0023] According to some embodiments of the present application, the sacrificial layer is etched by reactive ion etching to make the sacrificial layer flush with the silicon-based substrate;

[0024] Sacrificial layer shapes include: round, square or hexagonal

[0025] The diameter of the sacrificial layer or its inscribed circle is 20-80 μm;

[0026] The sacrificial layer is larger than the bottom electrode.

[0027] According to some embodiments of the present application, ultraviolet lithography or laser direct writing is used to obtain the top electrode, lead and top release hole photoresist structure;

[0028] Inductively coupled plasma coupled etching is used to obtain the top electrode, lead wire and top release hole;

[0029] The shapes of the top electrode include: circular, square, hexagonal or plum blossom.

[0030] According to some embodiments of the present application, the diameter of the top release hole is greater than 3 μm;

[0031] The diameter of the top electrode or its inscribed circle diameter is 25-100 μm;

[0032] The top electrode is larger than the sacrificial layer.

[0033] According to another aspect of the present application, there is provided a superconducting mechanical oscillator quantum device based on a self-aligned processing technology, which is obtained by the above-mentioned preparation method;

[0034] The superconducting mechanical oscillator quantum device comprises:

[0035] A silicon-based substrate, wherein a first surface of the silicon-based substrate has a groove;

[0036] A bottom electrode and a bottom lead, a groove surface of the first surface of the silicon-based substrate;

[0037] A top electrode, a lead and a top release hole, a first surface of the silicon-based substrate, and a covering groove; and

[0038] The suspended structure is located between the bottom electrode and the bottom lead and the top electrode, the lead and the top release hole, and the suspended structure is flush with the first surface of the silicon-based substrate.

[0039] Compared with the prior art, this application has at least the following beneficial effects:

[0040] The present application provides a method for preparing a superconducting mechanical oscillator quantum device based on a self-aligned processing technology. Through self-alignment, after a photolithography exposure is completed, two steps of etching and coating stripping are performed, and grooves and metals with consistent patterns are processed at the same time to achieve the effect of eliminating steps.

[0041] In the preparation method of the superconducting mechanical oscillator quantum device based on the self-aligned processing technology of the present application, a flat suspended superconducting mechanical oscillator can be constructed without the need for a chemical mechanical polishing step, which can effectively improve the quality and yield of the mechanical oscillator, and at the same time, the processing technology is simple and highly repeatable. In the processing method of the present application, a chemical mechanical polishing step is not required, which can avoid the unevenness of chemical mechanical polishing. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a method for preparing a superconducting mechanical oscillator quantum device based on a self-aligned processing technology according to Example 1 of the present application.

[0043] Illustration description: 1 silicon-based substrate, 2 bottom electrode and bottom lead photoresist structure, 3 bottom electrode and bottom lead, 4 sacrificial layer photoresist structure, 5 sacrificial layer, 6 top electrode and top lead, 7 top electrode, lead and top release hole photoresist structure, 8 top release hole, 9 suspended structure.

[0044] Figure 2 Schematic diagram of the working state of a mechanical oscillator (top: planar microwave cavity structure, bottom: three-dimensional microwave cavity structure).

[0045] Figure 3 This is a flow chart of the stacking preparation process for traditional superconducting mechanical oscillators.

[0046] Figure 4 This is the CMP process for traditional superconducting mechanical oscillators.

[0047] Figure 5 Confocal microscope scanning structure plane height map of the suspended mechanical oscillator prepared for the exemplary embodiment of the present application.

[0048] Figure 6 A three-dimensional display of the confocal microscope scanning structure of the suspended mechanical oscillator prepared for the exemplary embodiment of the present application.

[0049] Figure 7 A confocal microscope scan of the cross-sectional height map of the suspended mechanical oscillator prepared for the exemplary embodiment of the present application. DETAILED DESCRIPTION

[0050] 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.

[0051] 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.

[0052] 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.

[0053] The application is described in detail below.

[0054] At present, the preparation of traditional superconducting mechanical oscillators is mainly based on a layer-by-layer stacking process, which results in the suspended part of the mechanical oscillator being multi-layered and stepped. The structure is complex and unstable, leading to preparation failure and poor quality factor.

[0055] If chemical mechanical polishing (CMP) is used to prepare flat mechanical oscillators, the processing technology is complicated and the polishing rate is difficult to control, making it difficult to accurately control the spacing of the suspended structure; in combination with ion beam milling (IBE) using argon plasma bombardment, in the absence of a cut-off layer, its stop time depends on empirical judgment. CMP has poor uniformity on substrates of 2 inches or larger, resulting in only some areas meeting the requirements, which is not suitable for large-scale preparation; CMP equipment is expensive and brings many new technical difficulties, which is incompatible with the traditional mechanical oscillator process that only requires lithography and etching.

[0056] This application uses self-alignment to perform etching and coating stripping after a photolithography exposure, and simultaneously processes grooves and metals with consistent patterns, thereby achieving the effect of eliminating steps. This application optimizes the process steps, and the accuracy on the same wafer depends entirely on the stability of the etching rate and coating rate, which are relatively mature in the micro-electromechanical system (MEMS) processing, avoiding the unevenness of CMP. At the same time, this application can construct a flat superconducting mechanical oscillator to achieve a higher quality factor and yield rate; it is a new technical means for superconducting mechanical oscillator processing.

[0057] The micro-nano processing method of the mechanical vibrator of the present application includes:

[0058] On the first surface of the silicon substrate, negative photoresist is spin-coated and baked, and then positive photoresist is spin-coated and baked; after ultraviolet lithography or laser direct writing exposure, it is developed and fixed with deionized water to obtain the bottom electrode and bottom lead photoresist structure, which is then developed and baked.

[0059] After removing the residual glue by oxygen plasma, the silicon substrate is etched by reactive ion etching, using CHF3 and SF6 as the gas, and a groove is obtained by etching down 190nm-210nm. A first superconducting metal film of 90-110nm is plated on the first surface of the silicon substrate with the bottom electrode and bottom lead photoresist structure by electron beam evaporation.

[0060] The silicon substrate having the bottom electrode and bottom lead photoresist structure and the first superconducting metal film is immersed in a water bath in an N-methylpyrrolidone (NMP) solution, and then stripped to remove the photoresist to obtain the bottom electrode and the bottom lead.

[0061] The bottom electrode is generally circular with a diameter of about 10-50 μm; it can also be square, hexagonal, etc. The bottom lead can be a microstrip line with a width greater than 2 μm.

[0062] On the first surface of the silicon-based substrate where the bottom electrode and the bottom lead are formed, negative photoresist is spin-coated, baked, and then positive photoresist is spin-coated, baked, developed after ultraviolet lithography or laser direct writing exposure, fixed with deionized water, to obtain a sacrificial layer photoresist structure, and baked after development.

[0063] After removing the residual glue by oxygen plasma, reactive ion etching is used to etch the area outside the sacrificial layer photoresist structure on the first surface of the silicon-based substrate. CHF3 and SF6 are used as gases, and a step profiler, confocal microscope or atomic force microscope is used for continuous measurement to etch down about 100nm, so that the bottom electrode in the silicon groove is flush with the first surface of the silicon substrate.

[0064] By using electron beam evaporation, a sacrificial layer material, such as 100nm-150nm silicon oxide, is plated on the first surface of a silicon-based substrate having a bottom electrode, a bottom lead and a sacrificial layer photoresist structure. The silicon substrate is immersed in a water bath in an N-methylpyrrolidone (NMP) solution for stripping, and the photoresist is removed to obtain a sacrificial layer.

[0065] The sacrificial layer is generally circular with a diameter of about 20-80 μm; it can also be square, hexagonal, etc. The sacrificial layer needs to be larger than the bottom electrode.

[0066] The sacrificial silicon oxide is etched by reactive ion etching, with 5% SiH4 / N2 and N2O as the gas, and the step profiler, confocal microscope or atomic force microscope are used to continuously measure, so that the etching is down to about 50nm, so that the sacrificial silicon oxide is flush with the first surface of the silicon substrate. (If the etching accuracy and coating accuracy are sufficient, and the thickness of the sacrificial layer material is precisely controlled, this step can be skipped)

[0067] Electron beam evaporation is used to plate a 120-180nm second superconducting metal film on the first surface of a silicon substrate with a sacrificial layer; positive photoresist is spin-coated, baked, and developed after UV lithography or laser direct writing exposure, fixed with deionized water to obtain a photoresist structure of a top electrode, a lead, and a top release hole, and baked after development. After oxygen plasma is used to remove the residual glue, the second superconducting metal film is etched using inductively coupled plasma, with the gas being Cl2, BCl3, and HBr; a top aluminum electrode, a lead, and a top release hole are obtained. In dry HF gas, the sacrificial layer is completely removed through the top release hole to obtain a suspended spacing, and the top electrode is a superconducting mechanical oscillator, and the spacing size is determined by the sacrificial layer.

[0068] Among them, the top electrode is generally a circle with a diameter of 25-100μm, which must be larger than the sacrificial layer; the top electrode can also be designed into special shapes such as square, hexagonal, plum blossom, etc. according to needs; the top release hole is generally a circle with a diameter greater than 3μm, and other shapes that can achieve release effects are also within the scope of this application.

[0069] The connection between the suspended structure and the substrate of the suspended mechanical oscillator prepared by the micro-nano processing method of the present application is completely flat, which is a brand-new technical means for processing superconducting mechanical oscillators.

[0070] The technical solution of the present application is further described below in conjunction with specific embodiments.

[0071] Example

[0072] On the first surface of a 500 μm thick intrinsic high-resistance silicon substrate, negative photoresist LOR5A is spin-coated and baked at 180°C for 300 seconds, and then positive photoresist S1813 is spin-coated and baked at 115°C for 60 seconds. After ultraviolet lithography or laser direct writing exposure, it is developed in AZ MIF300 developer for 60 seconds and fixed with deionized water for 60 seconds to obtain a circular bottom electrode photoresist structure with a diameter of 10 μm and a microstrip line bottom lead photoresist structure of 3 μm, which are baked at 115 degrees for 60 seconds after development.

[0073] After removing the residual glue by oxygen plasma, the silicon substrate is etched down 200nm by CHF3 and SF6 reactive ion etching to obtain a groove.

[0074] A 100 nm aluminum film is deposited on the first surface of the silicon substrate having the bottom electrode and bottom lead photoresist structure by electron beam evaporation.

[0075] The silicon substrate having the above structure is immersed in an N-methylpyrrolidone solution in a water bath at 80° C. for 2 hours for stripping, and the photoresist is removed to obtain a superconducting metal aluminum bottom electrode and a bottom lead.

[0076] On the first surface of the silicon substrate which can be the bottom electrode and the bottom lead, spin-coat the negative photoresist LOR5A, bake at 180°C for 300s, then spin-coat the positive photoresist S1813, bake at 115°C for 60s, after UV lithography or laser direct writing exposure, develop in AZMIF300 developer for 60s, fix in deionized water for 60s, and obtain a circular sacrificial layer photoresist structure with a diameter of 20μm, and bake at 115 degrees for 60s after development.

[0077] After removing the residual glue by oxygen plasma, the area outside the sacrificial layer photoresist structure on the first surface of the silicon substrate is etched by reactive ion etching. CHF3 and SF6 are used as gases, and a step profiler, confocal microscope or atomic force microscope is used for continuous measurement. The etching is carried out downward by about 100nm, so that the bottom electrode in the silicon groove is flush with the first surface of the silicon substrate.

[0078] By electron beam evaporation, a 150 nm sacrificial silicon oxide material is plated on the first surface of the silicon-based substrate having the bottom electrode, the bottom lead and the sacrificial photoresist structure.

[0079] The silicon substrate having the above structure was immersed in an N-methylpyrrolidone (NMP) solution in a water bath at 80° C. for 2 hours, and then stripped to remove the photoresist to obtain a sacrificial silicon oxide layer.

[0080] The sacrificial silicon oxide layer is etched by reactive ion etching, with 5% SiH4 / N2 and N2O as the gas, and a step profiler, confocal microscope or atomic force microscope is used to continuously measure, and the sacrificial silicon oxide layer is etched down by 50nm to make it flush with the first surface of the silicon substrate.

[0081] A 150 nm aluminum film is deposited on the first surface of the silicon substrate having a sacrificial layer of silicon oxide by electron beam evaporation.

[0082] Spin-coat positive photoresist S1813, bake at 115℃ for 60s, and after UV lithography or laser direct writing exposure, develop in AZ MIF300 developer for 60s, fix in deionized water for 60s, define the photoresist structure of the top electrode, lead and top release hole, and bake at 115℃ for 180s after development. The top electrode has a diameter of 25 and the top release hole has a diameter of 4μm.

[0083] After removing the residual glue by oxygen plasma, the aluminum film is etched by inductively coupled plasma with the gases Cl2, BCl3, and HBr; the top aluminum electrode, lead and top release hole are obtained.

[0084] All sacrificial silicon oxide layers are completely removed in dry HF gas to obtain a suspended spacing of about 100 nm, and the top electrode is a superconducting mechanical oscillator.

[0085] like Figure 2 The figure shows the working schematic diagram of the mechanical vibrator of the present application. Its vibrating top electrode and bottom electrode form a variable capacitor, which can be combined with other devices through the upper and lower electrode leads: for example, an external inductor forms an LC loop, and the vibrator is placed in the center of the 3D resonant cavity to form a coupled LC loop. The position of the mechanical vibrator will affect the eigenfrequency of the LC loop, so that the vibration signal can be detected.

[0086] like Figure 5-7 All shown are confocal microscope scanning structures of the suspended mechanical oscillator of the present application. Figure 5 It is a plane height map, and its grayscale reflects the height of the device; the plum blossom structure is the top suspended electrode; the black area is the groove structure where the sacrificial layer is removed; the grayscale part is the contour grayscale map of the top suspended electrode, and its grayscale levels are evenly distributed. Figure 6 For three-dimensional display. Figure 7 It is the height of a cross section, from left to right, the substrate, the thickness of the top electrode supported on the substrate, about 150nm, the bulge-like area is the suspended area, it can be seen that it is suspended uniformly, and there is no step caused by the bottom electrode and the sacrificial layer inside the suspended range.

[0087] Comparative Example

[0088] like Figure 3 As shown, this is a flow chart of the stacking preparation process of traditional superconducting mechanical oscillators. This stacking process constructs a suspended mechanical oscillator by releasing a sacrificial layer. Although the process flow is simple, the configuration of the suspended part is complex, resulting in low yield and poor quality factor.

[0089] like Figure 4The figure shows the CMP process. The CMP rate is unstable and the IBE etching lacks a cutoff layer, which makes it difficult to control the suspension distance of the mechanical oscillator suspension structure. On a 2-inch or larger substrate, the CMP polishing is not uniform enough, and only a small area can be selected for the next step, which makes it difficult to prepare in large quantities.

[0090] The method for flattening the mechanical oscillator of the present application only uses ultraviolet lithography or laser direct writing, as well as etching processes of silicon, silicon oxide, and superconducting metals. The relevant processes are mature and stable, and are easy to integrate with other micro-electromechanical systems (MEMS) and superconducting quantum bit devices. This process solves the problem that the traditional superconducting mechanical oscillator and the substrate transition edge are step-shaped, resulting in the collapse of the suspended structure and poor quality factor.

[0091] The micro-nano processing technology of this application avoids the unevenness problem caused by chemical mechanical polishing and has good compatibility on substrates of 2 inches and above. The spacing between the suspended vibrator and the bottom electrode is an important parameter in the experimental design, and 100nm is generally the optimal value. The suspension spacing of the suspended structure of this process is controlled by the etching and coating steps, and can be accurately adjusted in MEMS processing, avoiding the problem of large or small spacing caused by polishing and ion beam milling.

[0092] 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 superconducting mechanical oscillator quantum device based on a self-aligned processing technology, characterized in that: include: Prepare a bottom electrode and bottom lead photoresist structure on the first surface of the silicon-based substrate by photolithography, then etch the first surface of the silicon-based substrate with the bottom electrode and bottom lead photoresist structure, so that the first surface of the silicon-based substrate has a groove of the bottom electrode and bottom lead photoresist structure; grow a first superconducting metal film on the first surface of the silicon-based substrate with the groove of the bottom electrode and lead photoresist structure, and peel off the first superconducting metal film outside the groove area to obtain a bottom electrode and a bottom lead; Performing photolithography on the first surface of the silicon-based substrate where the bottom electrode and the bottom lead are formed to prepare a sacrificial layer photoresist structure, and then etching the area outside the sacrificial layer photoresist structure on the first surface of the silicon-based substrate to make the bottom electrode flush with the first surface of the silicon-based substrate; growing a sacrificial dielectric on the first surface of the silicon-based substrate having the bottom electrode, the bottom lead and the sacrificial layer photoresist structure, and stripping off the sacrificial dielectric outside the sacrificial layer photoresist structure to obtain a sacrificial layer; Etching the sacrificial layer so that the sacrificial layer is flush with the first surface of the silicon-based substrate; Growing a second superconducting metal thin film on the first surface of the silicon-based substrate having the sacrificial layer; After preparing a photoresist structure of a top electrode, a lead and a top release hole on the surface of the second superconducting metal film, etching to obtain the top electrode, the lead and the top release hole; as well as The sacrificial layer is removed through the top release hole to obtain a suspended mechanical vibrator.

2. The preparation method according to claim 1, characterized in that: Growing the first superconducting metal film and the second superconducting metal film by electron beam evaporation technology; The materials of the first superconducting metal film and the second superconducting metal film include: aluminum, niobium or tantalum.

3. The preparation method according to claim 1, characterized in that: The bottom electrode and lead photoresist structure are obtained by ultraviolet lithography or laser direct writing; The shape of the bottom electrode includes: circle, square or regular hexagon; The bottom electrode has a diameter or an inscribed circle diameter of 10-50 μm.

4. The preparation method according to claim 1 or 3, characterized in that: The bottom lead is a microstrip line with a width greater than 2 μm.

5. The preparation method according to claim 1, characterized in that: The groove depth is 190-210 nm; The thickness of the first superconducting metal film is 90-110 nm; the thickness of the second superconducting metal film is 120-180 nm; The difference between the groove depth and the thickness of the first superconducting metal film is 80-120 nm.

6. The preparation method according to claim 1, characterized in that: The sacrificial layer photoresist structure is obtained by ultraviolet lithography or laser direct writing, and the sacrificial layer is grown by electron beam evaporation technology; The sacrificial dielectric material includes: silicon oxide; The thickness of the sacrificial layer is 100nm-150nm.

7. The preparation method according to claim 1 or 6, characterized in that: Reactive ion etching is used to etch the sacrificial layer so that the sacrificial layer is flush with the silicon-based substrate; The shape of the sacrificial layer includes: circular, square or hexagonal The diameter of the sacrificial layer or its inscribed circle is 20-80 μm; The sacrificial layer is larger than the bottom electrode.

8. The preparation method according to claim 1, characterized in that: The top electrode, lead and top release hole photoresist structure are obtained by ultraviolet lithography or laser direct writing; Inductively coupled plasma coupled etching is used to obtain the top electrode, lead wire and top release hole; The top electrode may have a shape of a circle, a square, a hexagon or a plum blossom.

9. The preparation method according to claim 1 or 8, characterized in that: The diameter of the top release hole is greater than 3 μm; The diameter of the top electrode or the diameter of its inscribed circle is 25-100 μm; The top electrode is larger than the sacrificial layer.

10. A superconducting mechanical oscillator quantum device based on a self-aligned processing technology, characterized in that: Obtained by the preparation method described in any one of claims 1 to 9; the superconducting mechanical oscillator quantum device comprises: A silicon-based substrate, wherein a first surface of the silicon-based substrate has a groove; A bottom electrode and a bottom lead are located on the surface of the groove on the first surface of the silicon-based substrate; A top electrode, a lead and a top release hole are located on the first surface of the silicon-based substrate and cover the groove; and The suspended structure is located between the bottom electrode and the bottom lead and the top electrode, the lead and the top release hole, and the suspended structure is flush with the first surface of the silicon-based substrate.

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