WO2023108877A1

WO2023108877A1 - Micron-scale acoustic field generation device based on an artificial structure and preparation method therefor

Info

Publication number: WO2023108877A1
Application number: PCT/CN2022/076196
Authority: WO
Inventors: 孟龙; 周伟; 郑海荣; 牛丽丽; 彭本贤; 刘晓峻; 程营; 刘文杰
Original assignee: 中国科学院深圳先进技术研究院
Priority date: 2021-12-18
Filing date: 2022-02-14
Publication date: 2023-06-22
Also published as: CN116322270A

Abstract

A micron-scale acoustic field generation device (100) based on an artificial structure and a preparation method therefor. The micron-scale acoustic field generation device (100) based on an artificial structure comprises a surface acoustic wave chip (10), and at least one artificial structure (20) coupled to the surface acoustic wave chip (10). The surface acoustic wave chip (10) is used for generating a surface acoustic wave field, and the artificial structure (20) is used for regulating and controlling the surface acoustic wave field generated by the surface acoustic wave chip (10), such that the range of the surface acoustic wave field is smaller than the wavelength of the acoustic wave, a micron-scale acoustic field is then formed, and thus a surface acoustic wave field with a single neuron scale is generated. The regulation and control of a single neuron are achieved, the single neuron discharge is recorded in combination with an electrophysiological means, and therefore the mechanism of ultrasonic nerve regulation and control is studied.

Description

Micron-scale sound field generating device based on artificial structure and its preparation method

technical field

The invention relates to the technical field of ultrasonic regulation, in particular to a micron-scale sound field generating device based on an artificial structure and a preparation method thereof.

Background technique

For a long time, mental diseases such as movement disorders, pain, epilepsy, Parkinson's disease, mental illness and angina pectoris have seriously affected human health and quality of life. Although new antipsychotic drugs have been used clinically, there are still quite a few patients who are not sensitive to drug treatment or are not satisfied with the efficacy. Neuromodulation therapy is a relatively popular treatment method in recent years. It has a good therapeutic effect on a variety of neurological diseases and is developing rapidly. Neuromodulation is the excitation, inhibition or regulation of neurons or neural signal transduction in adjacent or distant parts of the central nervous system, peripheral nervous system and autonomic nervous system through implantable or non-implantable technology, electrical or chemical action function, so as to improve the quality of life of patients and improve the biomedical engineering technology of neurological function.

Ultrasound neuromodulation is a neuromodulation method proposed in recent years. It can non-invasively penetrate the skull to regulate the nerve nuclei of the brain. It has received extensive attention in the treatment of Parkinson's, epilepsy and other diseases. However, ultrasonic neuromodulation mechanism is not clear. At present, ultrasonic nerve regulation is mainly carried out through ultrasonic transducers. However, the range of sound fields generated by traditional transducers is huge, much larger than the size of a single neuron cell, so that all types of neurons within the range of the sound field will be stimulated by ultrasonic waves. It is limited to study the mechanism of ultrasound neuromodulation from the perspective of single neurons.

Contents of the invention

An object of the present invention is to provide a micron-scale sound field generating device based on an artificial structure and a preparation method thereof. The device can regulate the sound field so that the range of the sound field is smaller than the size of a single neuron, which is convenient for ultrasonic monitoring from the perspective of a single neuron. The study of neuromodulatory mechanisms.

In one aspect, the present invention provides a micron-scale sound field generation device based on an artificial structure, the micron-scale sound field generation device based on an artificial structure includes a surface acoustic wave chip and at least one artificial structure coupled to the surface acoustic wave chip, the The surface acoustic wave chip is used to generate a surface wave sound field, and the artificial structure is used to regulate the surface wave sound field generated by the surface acoustic wave chip, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave, thereby forming a micron-scale sound field.

In an embodiment of the present invention, the surface acoustic wave chip includes a piezoelectric substrate and interdigital electrodes plated on the piezoelectric substrate, and the artificial structure is coupled to the surface acoustic wave chip provided with a Said interdigitated electrode side.

In one embodiment of the present invention, the piezoelectric substrate is 128° YX double-sided polished lithium niobate, Y36 tangential lithium niobate, X tangential lithium niobate, bismuth germanate, lithium tantalate, gallium arsenide , zinc oxide, aluminum nitride in any one.

In an embodiment of the present invention, the artificial structure includes a filled artificial structure, and the filled artificial structure includes a structural base and a filling material filling holes in the structural base, and the filling material is gallium, zinc , copper, nickel, lead in one or more.

In an embodiment of the present invention, the artificial structure is a columnar artificial structure, and the columnar artificial structure includes a structural base and periodically arranged columnar structures formed on the structural base.

In an embodiment of the present invention, the artificial structure is coupled to the surface acoustic wave chip through any one of water, agar, and polyvinyl alcohol resin.

In another aspect, the present invention also provides a method for preparing a micron-scale sound field generating device based on an artificial structure, comprising the steps of:

S1. Prepare a surface acoustic wave chip;

S2, preparing an artificial structure; and

S3. Coupling the artificial structure to the surface acoustic wave chip, using the artificial structure to regulate the surface wave sound field generated by the surface acoustic wave chip, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave, thereby forming a micron-scale sound field .

In an embodiment of the present invention, the step S1 includes the steps of:

S11. On the surface of the piezoelectric substrate, spin-coat positive photoresist, and heat and bake;

S12, covering the film sheet on the piezoelectric substrate coated with photoresist for exposure and developing;

S13, performing magnetron sputtering on the developed piezoelectric substrate to grow and form a metal layer on its surface; and

S14. Put the piezoelectric substrate with the metal layer grown on the surface into an acetone solution, and ultrasonically clean it to remove the photoresist, so as to obtain the surface acoustic wave chip.

In an embodiment of the present invention, the step S2 includes the steps of:

S21, spin-coating a negative photoresist on the surface of the structure substrate;

S22. Covering the film sheet on the structural substrate of the spin-coated negative photoresist for exposure, and developing to display the target etching position;

S23. Etching the target etching position to form a filling hole on the structural substrate; and

S24. Fill the filling hole with a filling substance, and after the filling substance solidifies, polish the surface of the solidified structure to obtain the artificial structure.

In an embodiment of the present invention, wherein in the step S24, the filler is filled in the filling hole by microinjection, and the filling substance is gallium, zinc, copper, nickel, lead one or more of .

In an embodiment of the present invention, the step S2 includes the steps of:

S210, spin-coating a negative photoresist on the surface of the structure substrate;

S220, covering the film sheet on the structural base of the spin-coated negative photoresist for exposure, and developing to display the target etching position;

S230. Etching the target etching position to form periodically arranged columnar structures on the structural substrate; and

S240, removing the negative photoresist on the columnar structure to obtain a columnar artificial structure.

In an embodiment of the present invention, in the step S240, the negative photoresist is removed by ultrasonic cleaning or polishing.

In an embodiment of the present invention, in the step S3, the artificial structure is coupled to the surface acoustic wave chip through any one of water, agar, and polyvinyl alcohol resin.

The artificial structure-based micron-scale sound field generation device of the present invention is formed by coupling the surface acoustic wave chip with the artificial structure, and the surface acoustic wave chip can be well compatible with the artificial structure, so as to control the sound field to realize the micron-scale sound field Formation; the specific structure of the artificial structure can make it produce the singular characteristics in nature, so that the sound wave can be effectively manipulated, and the regulation of the surface wave sound field generated by the surface acoustic wave chip can be realized, and can be designed according to actual needs. Different structural forms can produce the surface wave sound field of the desired form.

The present invention combines the surface acoustic wave chip and the artificial structure to form a micron-scale sound field generating device based on the artificial structure, which generates a surface wave sound field at the scale of a single neuron, realizes the regulation of a single neuron, and combines electrophysiological means to control a single neuron. Neuron firing can be recorded to study the mechanism of ultrasound neuromodulation.

The artificial structure-based micron-scale sound field generating device of the present invention is based on the acoustic artificial structure to regulate the sound field, and only needs at least one vibrating element (that is, a single vibrating element surface acoustic wave chip) and at least one acoustic artificial structure to achieve the regulation of the sound field The purpose is simple in structure, low in cost and easy to realize.

Further objects and advantages of the invention will fully appear from an understanding of the ensuing description and accompanying drawings.

Description of drawings

Fig. 1 is a schematic structural diagram of the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 2 is a schematic diagram of the manufacturing process of the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 3 is a simulation diagram of the micron-scale sound field generated by the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 4 is a schematic block diagram of the manufacturing method of the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 5 is a schematic block diagram of a method for fabricating a surface acoustic wave chip of the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 6 is a schematic block diagram of a method for preparing a filled artificial structure based on the artificial structure-based micron-scale sound field generating device according to the first preferred embodiment of the present invention.

Fig. 7 is a schematic structural diagram of the artificial structure-based micron-scale sound field generating device according to the second preferred embodiment of the present invention.

Fig. 8 is a schematic diagram of the manufacturing process of the artificial structure-based micron-scale sound field generating device according to the second preferred embodiment of the present invention.

Fig. 9 is a simulation diagram of the micron-scale sound field generated by the artificial structure-based micron-scale sound field generating device according to the second preferred embodiment of the present invention.

Fig. 10 is a schematic block diagram of the preparation method of the columnar artificial structure of the artificial structure-based micron-scale sound field generating device according to the second preferred embodiment of the present invention.

Fig. 11 is a schematic structural diagram of the artificial structure-based micron-scale sound field generating device according to the third preferred embodiment of the present invention.

Fig. 12 is a schematic structural diagram of the artificial structure-based micron-scale sound field generating device according to the fourth preferred embodiment of the present invention.

Description of reference numerals: artificial structure-based micron-scale sound field generating device 100; surface acoustic wave chip 10; piezoelectric substrate 11; interdigitated electrodes 12; artificial structure 20; filled artificial structure 21; columnar artificial structure 22; structural substrate 211 ; filling hole 212 ; filling substance 213 ; columnar structure 221 ; coupling layer 30 ; positive photoresist 41 ; negative photoresist 42 .

Detailed ways

The following description serves to disclose the present invention to enable those skilled in the art to carry out the present invention. The preferred embodiments described below are only examples, and those skilled in the art can devise other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents and other technical solutions without departing from the spirit and scope of the present invention.

Those skilled in the art should understand that, in the disclosure of the present invention, the terms "vertical", "transverse", "upper", "lower", "front", "rear", "left", "right", The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present invention and simplified description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, so the above terms should not be construed as limiting the present invention.

It can be understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element The quantity can be multiple, and the term "a" cannot be understood as a limitation on the quantity.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected, or electrically connected, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction of two components relation. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

Surface acoustic wave, also called Rayleigh wave, is an ultrasonic wave that propagates along the surface of an object, and is usually generated by an interdigital transducer. The interdigital transducer is formed by plating interdigital electrodes on a piezoelectric substrate. When a sine wave signal of a certain frequency is used, a surface wave signal of the corresponding frequency is generated. It has the characteristics of high frequency, miniaturization and low energy loss. As a sound source, the surface wave chip can be well compatible with micro-artificial structures, thereby adjusting the sound field to achieve the formation of a micron-level sound field.

By artificially designing a specific structure, the acoustic artificial structure can produce singular characteristics that do not exist in nature, thereby effectively manipulating sound waves, realizing the regulation of the sound field, and can design different structural forms according to actual needs, so as to produce the desired shape. sound field.

Therefore, the micron-scale sound field generation device based on the artificial structure of the present invention combines the surface acoustic wave chip and the acoustic artificial structure, and the surface acoustic wave chip is a micro-ultrasound generation device, which can be used with neurobiological means such as calcium imaging and patch clamp. Compatible features to realize the recording of neural electrical activity. The acoustic artificial structure can regulate the surface wave sound field generated by the surface acoustic wave chip, so that the sound wave is localized within the range of a single neuron, so as to realize precise regulation of a single neuron. In this way, the present invention can combine electrophysiological recording to realize the research on the mechanism of ultrasonic nerve regulation at the single neuron scale.

The present invention regulates the sound field based on the acoustic artificial structure, only needs at least one vibration element and at least one acoustic artificial structure to achieve the purpose of regulating the sound field, has a simple structure, low cost, and is easy to realize.

As shown in FIGS. 1 to 12 , the artificial structure-based micron-scale sound field generating device 100 of the present invention and its manufacturing method are specifically illustrated.

As shown in Figures 1 to 6, the specific structure and preparation method of the artificial structure-based micron-scale sound field generating device 100 according to the first preferred embodiment of the present invention are illustrated. Specifically, the artificial structure-based micron-scale sound field generating device 100 includes a surface acoustic wave chip 10 and at least one artificial structure 20 coupled to the surface acoustic wave chip 10, and the surface acoustic wave chip 10 is used to generate surface waves Sound field, the artificial structure 20 is used to regulate the surface wave sound field generated by the surface acoustic wave chip 10, so that the range of the surface wave sound field is smaller than the sound wave wavelength, thereby forming a micron-scale sound field.

In particular, the artificial structure 20 is coupled to the surface acoustic wave chip 10 through a substance with good conduction characteristics, such as the artificial structure 20 is coupled to the surface acoustic wave chip 10 through any one of water, agar, and polyvinyl alcohol resin. A coupling layer 30 is also formed between the surface acoustic wave chip 10 , that is, the artificial structure 20 and the surface acoustic wave chip 10 .

Further, the surface acoustic wave chip 10 includes a piezoelectric substrate 11 and an interdigital electrode 12 plated on the piezoelectric substrate 11, and the artificial structure 20 is coupled to the arrangement of the surface acoustic wave chip 10. One side of the interdigitated electrode 12.

It is worth mentioning that the piezoelectric substrate 11 is 128 ° YX double-sided polished lithium niobate, Y36 tangential lithium niobate, X tangential lithium niobate, Bi ₁₂ GeO ₂ (bis-germanic acid), LiTaO ₃ ( Lithium tantalate), GaAs (gallium arsenide), ZnO (zinc oxide), and AlN (aluminum nitride).

Preferably, in this embodiment of the present invention, in order to obtain a larger electromechanical coupling coefficient, lithium niobate polished on both sides of 128° YX is selected as the piezoelectric substrate 11 .

Further, in this embodiment of the present invention, the artificial structure 20 adopts a filling type artificial structure 21, and the filling type artificial structure 21 includes a structural base 211 and filling holes 212 filled in the structural base 211. Substance 213, wherein the structural base 211 can be any one of silicon wafer or tungsten wafer, the filling material 213 is a material with a huge difference in acoustic impedance from the structural base 211, such as the filling material 213 is gallium, One or more of zinc, copper, nickel, lead.

As shown in FIG. 2( a ) to FIG. 2( j ), the manufacturing process of the artificial structure-based micron-scale sound field generating device 100 of the first preferred embodiment of the present invention is specifically illustrated.

The preparation method of the micron-scale sound field generating device 100 based on the artificial structure is as follows:

(1) Prepare the surface acoustic wave chip 10

The preparation of the surface acoustic wave chip 10 is mainly made by plating interdigital electrodes 12 and recording electrodes on the piezoelectric substrate 11 . In order to obtain a larger electromechanical coupling coefficient, 128°YX double-sided polished lithium niobate is selected as the piezoelectric substrate 11 . The process of making the surface acoustic wave chip 10 mainly includes processes such as gluing, exposure, development, sputtering, and peeling off, wherein FIG. 2(a) to FIG. 2(d) show the surface acoustic wave chip 10. Production Method.

(1) Coating: Spin-coat positive photoresist 41 (such as photoresist AZ5214) at 3000 rpm on the surface of the thoroughly cleaned piezoelectric substrate 11 for 30 seconds, place the chip on a 65° C. heating plate and bake for 3 minutes. The thickness of the photoresist was tested using a step meter, and the thickness of the photoresist was about 1.5 μm, as shown in FIG. 2( a ).

(2) Exposure and development: Then cover the prepared film sheet on the structure shown in Figure 2(a) for exposure, wherein the film sheet has a part with a pattern that is opaque, and a part without a pattern that is transparent, and the photoresist corresponds to The part through which the light passes will be cured. To develop the structure covered with film sheet, mif300 can be used for development. When developing, the solidified part will be dissolved, and the uncured part will not be dissolved, and the development will form a pattern as shown in Figure 2(b). This is done. Pattern transfer of piezoelectric substrate 11.

(3) Sputtering: Magnetron sputtering is performed on the piezoelectric substrate 11 that has completed the pattern transfer, so that a metal layer with a thickness of about 200nm is grown on the surface, as shown in Figure 2(c). 11 to form interdigitated electrodes 12 .

(4) Stripping: Place the piezoelectric substrate 11 formed with electrodes in an acetone solution, and use the ultrasonic vibration of an ultrasonic cleaning machine to peel off the photoresist to complete the fabrication of the surface acoustic wave chip 10, as shown in Figure 2(d) .

It can be understood that the present invention can study the influence of these parameters on device insertion loss and device bandwidth by adjusting the metal film material, finger logarithm, and acoustic aperture size, and design the finger width of the surface acoustic wave chip, thereby regulating the acoustic The frequency of the surface wave.

(2) Preparation of filled artificial structures 21

The preparation process of the filled artificial structure 21 is shown in Figure 2(e) to Figure 2(i), the filled artificial structure 21 is mainly based on the near-field diffraction effect to realize the Controlling the sound field.

(1) Coating, exposure, and development: on the surface of the completely cleaned structural substrate 211, spin-coat negative photoresist 42 (such as photoresist SUN1300) at 3000rpm for 30s, and then cover the prepared film sheet on it , as shown in Figure 2(e), followed by exposure, in which the patterned part on the film sheet is opaque, the non-patterned part is light-transmissive, and the part of the photoresist layer that has light transmission will be cured, and the cured part will be cured during development. Dissolve, the uncured part is not dissolved, as shown in Figure 2(h), through the design of the film sheet, the dissolved part is the position to be etched, that is, the target etching position, as shown in Figure 2(f).

It is worth mentioning that since the artificial structure 20 needs to be etched, the negative photoresist is relatively thick and has a good protective effect during etching. It is also possible if a thick positive photoresist is selected, that is, the positive and negative photoresists used in the present invention can be used interchangeably. In addition, the positive and negative photoresists used in the present invention can also be used for micro-nano processing of photoresist. Such as SU-8, AZ4500, etc., the present invention is not limited thereto.

(2) Etching: the surface protection layer of the structural base 211 is etched by an etching method, and the position protection layer without photoresist is etched to form the required hole structure, which is preferably The circular hole-like structure is shown in Fig. 2(g).

In some embodiments of the present invention, the hole-like structure may also be square or irregular in shape, which is not limited in the present invention.

(3) Filling: fill the designed filling material into the etched pores by microinjection, and solidify, and use a grinder to polish the surface of the structure to obtain a filled artificial structure 21, as shown in Figure 2(i ) shown.

In some embodiments of the present invention, if the metal can be filled into the etched pores with the designed filling material by electroplating or e-book evaporation, and solidified, the present invention does not limit the filling method.

In addition, due to the material added by injection, the surface may be uneven after filling, which will affect the control effect, so it needs to be smoothed.

(3) Coupling of the filled artificial structure 21 and the surface acoustic wave chip 10

(1) Installation: the filled artificial structure 21 is coupled to the surface acoustic wave chip 10 through water or other sound-conducting materials to obtain a micron-scale sound field generating device based on an artificial structure as shown in FIG. 2(j) 100, so that the surface wave sound field generated by the filled artificial structure 21 and the surface acoustic wave chip 10 interacts to form a sound field of a desired shape.

In particular, the liquid (such as water) and the sound-conducting material only need to be completely filled between the artificial structure 20 and the surface of the surface acoustic wave chip 10 without air, thus completing the connection between the artificial structure 20 and the surface acoustic wave chip 10 The coupling between the surface acoustic wave chips 10 is described.

It is worth mentioning that the sound guide material can be any one of agar and polyvinyl alcohol resin, which is not limited in the present invention.

In particular, Fig. 3 is a simulation diagram of the micron-scale sound field generated by the artificial structure-based micron-scale sound field generating device according to the first preferred example of the present invention. The ordinate in the figure represents the sound wave intensity, and the larger the value, the darker the color , representing the greater the intensity of the sound wave. Normally, in the absence of artificial structures, the sound wave energy in the simulated sound field area is uniformly distributed and has a large range. As shown in Figure 3, after the present invention adds the filled artificial structure 21, the sound field energy generated by the surface acoustic wave chip 10 is focused to one or more small point-like areas, and the other positions The energy of the sound wave is much smaller than the point region, thus proving that the artificial structure-based micron-scale sound field generating device of the present invention can generate a micron-scale sound field.

That is to say, the artificial structure 20 of the present invention controls the surface wave acoustic field generated by the surface acoustic wave chip 10 to generate a micron-scale sound field of 5-150 μm, which is smaller than or equal to the scale of a single neuron. Therefore, the present invention can combine electrical Physiological technology, using the surface acoustic wave chip 10 to realize real-time recording of electrical signals under ultrasonic stimulation of a single neuron, so as to study the mechanism of ultrasonic nerve regulation from the perspective of a single neuron.

It can be understood that the present invention designs artificial structure dimensions and filling materials based on SAW frequency design, experimental sound field requirements and simulation results. The hole-like structure is prepared by glue coating, photolithography, development and etching, and the filling material is filled into the hole-like structure by microinjection and cured. The artificial structure 20 is coupled to the surface acoustic wave chip 10 through a liquid or a sound-conducting material to obtain the micron-scale sound field generating device based on the artificial structure.

That is to say, based on the aforementioned preparation process, the present invention also provides a preparation method of the artificial structure-based micron-scale sound field generating device 100, as shown in FIG. 4 , the artificial structure-based micron-scale sound field generation The preparation method of device 100 comprises steps:

S1. Prepare a surface acoustic wave chip 10;

S2. Prepare the artificial structure 20; and

S3. Coupling the artificial structure 20 to the surface acoustic wave chip 10, using the artificial structure 20 to regulate the surface wave sound field generated by the surface acoustic wave chip 10, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave , thus forming a micron-scale sound field.

Further, as shown in Figure 5, the step S1 includes the steps of:

S11, spin-coat positive photoresist 41 on the surface of piezoelectric substrate 11, and heat and bake;

S12, covering the film sheet on the piezoelectric substrate 11 coated with photoresist for exposure and developing;

S13. Perform magnetron sputtering on the developed piezoelectric substrate 11 to grow a metal layer on its surface; and

S14. Put the piezoelectric substrate 11 with the metal layer grown on the surface into an acetone solution, and ultrasonically clean it to remove the photoresist, and obtain the surface acoustic wave chip 10 .

Further, as shown in Figure 6, the step S2 includes the steps of:

S21. On the surface of the structural substrate 211, spin-coat a negative photoresist 42;

S22, covering the film sheet on the structural substrate 211 with the spin-coated negative photoresist 42 for exposure, and developing to display the target etching position;

S23. Etching the target etching position to form a filling hole 212 on the structural substrate 211; and

S24 , filling the filling hole 212 with the filling substance 213 , and after the filling substance 213 is solidified, smooth the surface of the solidified structure to obtain the filled artificial structure 21 .

It is worth mentioning that, in the step S24, the filler is filled in the filling hole 212 by means of microinjection, and the filling substance 213 is gallium, zinc, copper, nickel, lead one or more.

In addition, it is also worth mentioning that in the step S3, the artificial structure 20 is coupled to the surface acoustic wave chip 10 through any one of water, agar, and polyvinyl alcohol resin.

As shown in FIGS. 7 to 10 , the structure and manufacturing method of the artificial structure-based micron-scale sound field generating device 100 according to the second preferred embodiment of the present invention are specifically illustrated. The artificial structure-based micron-scale sound field generating device 100 includes a surface acoustic wave chip 10 and an artificial structure coupled to the surface acoustic wave chip 10, the surface acoustic wave chip 10 is used to generate a surface wave sound field, and the artificial structure 20 is used to regulate the surface wave sound field generated by the surface acoustic wave chip 10, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave, thereby forming a micron-scale sound field.

It can be understood that the second preferred embodiment is a modified embodiment of the first preferred embodiment, and the difference from the first preferred embodiment is that the artificial structure-based micron-scale sound field generating device 100 of the second preferred embodiment adopts Columnar artificial structures22. Specifically, the columnar artificial structure 22 includes a structural base 211 and periodically arranged columnar structures 221 formed on the structural base 211 .

It can also be understood that, except for the structure of the columnar artificial structure 22, other structures of the second preferred embodiment are the same as those of the first preferred embodiment, and the surface acoustic wave chip 10 of the second preferred embodiment The structure and preparation method are the same as those of the first preferred embodiment.

That is to say, in the second preferred embodiment, the columnar artificial structure 22 is different from the filled artificial structure 21 in the first preferred embodiment in structure and preparation method.

As shown in Figure 8(a) to Figure 8(i), the preparation method of the micron-scale sound field generating device 100 based on the artificial structure is as follows:

(1) Prepare the surface acoustic wave chip 10

The preparation of the surface acoustic wave chip 10 is mainly made by plating interdigital electrodes 12 and recording electrodes on the piezoelectric substrate 11 . In order to obtain a larger electromechanical coupling coefficient, 128°YX double-sided polished lithium niobate is selected as the piezoelectric substrate 11 . The process of making the surface acoustic wave chip 10 mainly includes processes such as gluing, exposure, development, sputtering, and peeling off, wherein FIG. 8(a) to FIG. 8(d) show the surface acoustic wave chip 10. Production Method.

(1) Coating: Spin-coat positive photoresist 41 (such as photoresist AZ5214) at 3000 rpm on the surface of the thoroughly cleaned piezoelectric substrate 11 for 30 seconds, place the chip on a 65° C. heating plate and bake for 3 minutes. The thickness of the photoresist was tested using a step meter, and the thickness of the photoresist was about 1.5 μm, as shown in FIG. 8( a ).

(2) Exposure and development: Then cover the prepared film sheet on the structure shown in Figure 8(a) for exposure, wherein the film sheet has a part with a pattern that is opaque, and a part without a pattern that is transparent, and the photoresist corresponds to The part through which the light passes will be cured. To develop the structure covered with film sheet, mif300 can be used for development. When developing, the solidified part will be dissolved, and the uncured part will not be dissolved. The pattern shown in Figure 8(b) will be formed after development. Pattern transfer of piezoelectric substrate 11.

(3) Sputtering: Magnetron sputtering is performed on the piezoelectric substrate 11 that has completed the pattern transfer, so that a metal layer with a thickness of about 200 nm grows on the surface, as shown in Figure 8(c). 11 to form interdigitated electrodes 12 .

(4) Stripping: Place the piezoelectric substrate 11 grown and formed with electrodes in an acetone solution, and use the ultrasonic vibration of an ultrasonic cleaning machine to peel off the photoresist to complete the fabrication of the surface acoustic wave chip 10, as shown in Figure 8(d) .

That is, the process of FIG. 8(a) to FIG. 8(d) is the same as the process of FIG. 2(a) to FIG. 2(d).

(2) Preparation of columnar artificial structures 22

The preparation process of the filled artificial structure 21 is shown in FIG. 8(e) to FIG. 8(i). The columnar artificial structure 22 generates a zero-dimensional angle at a specific position by constructing a high-order acoustic topological insulator. state, so as to realize the sub-wavelength focusing of the elastic wave, so as to realize the control of the surface wave sound field of the surface acoustic wave chip 10 .

(1) Coating, exposure, and development: on the surface of the completely cleaned structural substrate 211, spin-coat negative photoresist 42 (such as photoresist SUN1300) at 3000rpm for 30s, and then cover the prepared film sheet on it , as shown in Figure 8(e), followed by exposure, in which the patterned part on the film sheet is opaque, the non-patterned part is light-transmissive, and the part of the photoresist layer through which light passes will be cured, and the cured part will be cured during development. Dissolve, the non-cured part is not dissolved, and it is developed by the developer (mif300) as shown in Figure 8(h). Through the design of the film, the dissolved part is the position that needs to be etched, that is, the target etching position, as shown in Figure 8 (f) shown.

(2) Etching: the protective layer on the surface of the chip is etched by an etching method, and the positional protective layer without photoresist is etched to form the required periodic columnar structure 221, as shown in Figure 8(g) .

(3) Glue removal: remove the negative photoresist 42 on the columnar structure 221 by means of ultrasonic or grinding, and obtain the columnar artificial structure 22 .

(3) Coupling of the columnar artificial structure 22 and the surface acoustic wave chip 10

(1) Installation: the columnar artificial structure 22 is coupled to the surface acoustic wave chip 10 through water or other sound-conducting materials to obtain a micron-scale sound field generating device 100 based on an artificial structure as shown in FIG. 8(i) , so that the surface wave sound field generated by the columnar artificial structure 22 and the surface acoustic wave chip 10 interacts to form a sound field of a desired shape.

In particular, Fig. 9 is a simulation diagram of the micron-scale sound field generated by the artificial structure-based micron-scale sound field generating device according to the second preferred example of the present invention, the ordinate in the figure represents the sound wave intensity, and the larger the value, the darker the color , representing the greater the intensity of the sound wave. Normally, in the absence of artificial structures, the sound wave energy in the simulated sound field area is uniformly distributed and has a large range. As shown in Figure 9, after the present invention has added the columnar artificial structure 22, the sound field energy generated by the surface acoustic wave chip 10 is focused to one or more small point-shaped areas, and the sound waves at other positions The energy is much smaller than the point region, thus proving that the artificial structure-based micron-scale sound field generating device of the present invention can generate a micron-scale sound field.

It can be understood that the present invention designs the size and arrangement of the columnar artificial structure 22 through the surface acoustic wave frequency design, experimental sound field requirements and simulation results. The columnar artificial structure 22 is prepared by glue coating, photolithography, development and etching. The artificial structure-based micron-scale sound field generating device 100 is obtained by coupling the columnar artificial structure 22 to the surface acoustic wave chip 10 through a liquid or a sound-conducting material.

As shown in Figure 10, in the second preferred embodiment, the step S2 includes the steps of:

S210, spin coating a negative photoresist 42 on the surface of the structure substrate 211;

S220, covering the film sheet on the structural substrate 211 with the spin-coated negative photoresist 42 for exposure, and developing to display the target etching position;

S230. Etching the target etching position to form periodically arranged columnar structures 221 on the structural substrate 211; and

S240 , removing the negative photoresist 42 on the columnar structure 221 to obtain the columnar artificial structure 22 .

It is worth mentioning that, in the step S240, the negative photoresist 42 can be removed by ultrasonic cleaning or grinding, which is not limited in the present invention.

As shown in Fig. 11 and Fig. 12, the present invention also provides a micron-scale sound field generating device 100 based on artificial structures 20 using a plurality of artificial structures 20. In a third preferred embodiment, the artificial-based The micron-scale sound field generating device 100 of the structure can adopt two or more filling-type artificial structures 21, and can also adopt two or more columnar artificial structures 22; in the fourth preferred embodiment, the artificial-based Structured micron-scale sound field generating device 100 may also use a combination of filled artificial structures 21 and columnar artificial structures 22 to meet the requirements of different stimulation sites, which is not limited in the present invention.

It can be understood that the present invention uses the artificial structure 20 to regulate the surface wave sound field generated by the surface acoustic wave chip 10, so that the range of the sound field is smaller than the wavelength of the sound wave, localized to the scale of a single neuron, and the stimulation of a single neuron is realized. . Since the surface acoustic wave chip 10 and the artificial structure 20 are both prepared by micro-nano processing technology, the structure is small and compatible with calcium imaging, patch clamp and other means, so it is easy to study the neural regulation mechanism.

Moreover, since the artificial structure 20 includes a filled artificial structure 21 and a columnar artificial structure 22, through the structural design of the artificial structure 20, multiple precise focal points or different sound field shapes can be realized in a plane, thereby achieving Simultaneous stimulation of multiple locations.

In addition, the artificial structure-based micron-scale sound field generating device 100 of the present invention can be separated from the sound source. In use, one sound source can be used, and multiple artificial structures 20 can be used. On the artificial structure 20, the artificial structure 20 is continuously placed at the sound source for stimulation, thereby realizing high-throughput regulation.

It should also be understood that the artificial structure-based micron-scale sound field generating device of the present invention can be applied not only to the technical field of neuromodulation, but also to technical fields such as sonoporation, acoustic manipulation, and acoustic flow. The application of the micron-scale sound field generating device based on the artificial structure is not limited.

The technical features of the above embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be It is considered to be within the range described in this specification.

The above examples only express the preferred implementation of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the scope of the patent for the invention. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims

A micron-scale sound field generating device based on an artificial structure, characterized in that the artificial structure-based micron-scale sound field generating device includes a surface acoustic wave chip and at least one artificial structure coupled to the surface acoustic wave chip, and the surface acoustic wave The chip is used to generate a surface wave sound field, and the artificial structure is used to regulate the surface wave sound field generated by the surface acoustic wave chip, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave, thereby forming a micron-scale sound field.
The micron-scale sound field generating device based on an artificial structure according to claim 1, wherein the surface acoustic wave chip includes a piezoelectric substrate and interdigitated electrodes plated on the piezoelectric substrate, and the artificial structure Coupled to the side of the surface acoustic wave chip provided with the interdigital electrodes, the piezoelectric substrate is 128°YX double-sided polished lithium niobate, Y36 tangential lithium niobate, X tangential lithium niobate, germanium Any of bismuth, lithium tantalate, gallium arsenide, zinc oxide, and aluminum nitride.
The micron-scale sound field generating device based on an artificial structure according to claim 2, wherein the artificial structure includes a filled artificial structure, and the filled artificial structure includes a structural base and filling holes filled in the structural base The filling material is one or more of gallium, zinc, copper, nickel, and lead.
The micron-scale sound field generating device based on an artificial structure according to claim 2 or 3, wherein the artificial structure includes a columnar artificial structure, and the columnar artificial structure includes a structural base and a period formed on the structural base A columnar structure arranged in a row.
The artificial structure-based micron-scale sound field generating device according to any one of claims 1 to 3, wherein the artificial structure is coupled to the artificial structure through any one of water, agar, and polyvinyl alcohol resin Surface acoustic wave chip.
According to the preparation method of the micron-scale sound field generating device based on artificial structure according to any one of claims 1 to 5, it is characterized in that, comprising the steps:

S1. Prepare a surface acoustic wave chip;

S2, preparing an artificial structure; and

S3. Coupling the artificial structure to the surface acoustic wave chip, using the artificial structure to regulate the surface wave sound field generated by the surface acoustic wave chip, so that the range of the surface wave sound field is smaller than the wavelength of the sound wave, thereby forming a micron-scale sound field .
The method for preparing a micron-scale sound field generating device based on an artificial structure according to claim 6, wherein the step S1 comprises the steps of:

S11. On the surface of the piezoelectric substrate, spin-coat positive photoresist, and heat and bake;

S12, covering the film sheet on the piezoelectric substrate coated with photoresist for exposure and developing;

S13, performing magnetron sputtering on the developed piezoelectric substrate to grow and form a metal layer on its surface; and

S14. Put the piezoelectric substrate with the metal layer grown on the surface into an acetone solution, and ultrasonically clean it to remove the photoresist, so as to obtain the surface acoustic wave chip.
The method for preparing a micron-scale sound field generating device based on an artificial structure according to claim 6, wherein the step S2 includes the steps of:

S21, spin-coating a negative photoresist on the surface of the structure substrate;

S22. Covering the film sheet on the structural substrate of the spin-coated negative photoresist for exposure, and developing to display the target etching position;

S23. Etching the target etching position to form a filling hole on the structural substrate; and

S24. Fill the filling hole with a filling material, and after the filling material is cured, polish the surface of the cured structure to obtain a filled artificial structure.
The method for preparing a micron-scale sound field generating device based on an artificial structure according to claim 6, wherein the step S2 includes the steps of:

S210, spin-coating a negative photoresist on the surface of the structure substrate;

S220, covering the film sheet on the structural base of the spin-coated negative photoresist for exposure, and developing to display the target etching position;

S230. Etching the target etching position to form periodically arranged columnar structures on the structural substrate; and

S240, removing the negative photoresist on the columnar structure to obtain a columnar artificial structure.
According to the preparation method of the micron-scale sound field generating device based on artificial structure according to any one of claims 6 to 9, it is characterized in that, in said step S3, any one of water, agar, polyvinyl alcohol resin A substance is used to couple the artificial structure to the surface acoustic wave chip.