Method for manufacturing an ultrasonic transducer, ultrasonic transducer

Abstract

The application relates to a preparation method of an ultrasonic transducer and the ultrasonic transducer. The method comprises the following steps: preparing a first mixed solution in which preset polymers and first acoustic impedance monomers are dissolved; preparing a flexible backing layer film based on the first mixed solution; preparing a second mixed solution in which preset polymers and second acoustic impedance monomers are dissolved; preparing a flexible matching layer film based on the second mixed solution; preparing an active layer; and respectively attaching the flexible backing layer film and the flexible matching layer film to two sides of the active layer which are arranged oppositely. Since the backing layer and the matching layer are both flexible films, different curved surfaces can be attached, and various shapes of to-be-imaged parts can be adapted, so that the attachment degree of the ultrasonic transducer and the to-be-imaged part is improved, and higher-quality ultrasonic images can be acquired.

Description

Technical Field

[0001] This application relates to the field of ultrasonic testing technology, and in particular to a method for preparing an ultrasonic transducer and an ultrasonic transducer. Background Technology

[0002] An ultrasonic transducer is a device that images the internal tissues of an object by emitting ultrasonic signals and using the reflected ultrasonic signals. The ultrasonic transducer sends ultrasonic signals to the area of ​​the object to be imaged and generates image information of the area based on the ultrasonic signals reflected from the boundaries between the internal tissues of objects with different acoustic impedances.

[0003] In traditional technology, ultrasonic transducers are solid curved surface structures. Ultrasonic imaging is achieved by fitting the curved surface to the area to be imaged.

[0004] However, traditional ultrasonic transducers, being solid structures, cannot adapt well to various curved surfaces, resulting in lower quality ultrasonic imaging for areas that do not fit the surface well. Summary of the Invention

[0005] Therefore, it is necessary to provide a method for fabricating an ultrasonic transducer that can fit different imaging sites, and an ultrasonic transducer in order to address the above-mentioned technical problems.

[0006] A method for fabricating an ultrasonic transducer, the method comprising: preparing a first mixed solution containing a preset polymer and a first acoustic impedance monomer; fabricating a flexible backing layer film based on the first mixed solution; preparing a second mixed solution containing the preset polymer and a second acoustic impedance monomer; fabricating a flexible matching layer film based on the second mixed solution; fabricating an active layer; and attaching the flexible backing layer film and the flexible matching layer film to two opposite sides of the active layer, respectively.

[0007] In one embodiment, the method further includes: preparing a third mixed solution in which the preset polymer is dissolved; preparing a first encapsulation layer film and a second encapsulation layer film based on the third mixed solution; forming the flexible backing layer film on the first encapsulation layer film; and forming the flexible matching layer film on the second encapsulation layer film.

[0008] In one embodiment, the preparation of the active layer includes: preparing a first electrode layer, a piezoelectric layer, and a second electrode layer that are stacked sequentially; the attachment of the flexible backing film and the flexible matching layer film to two opposite sides of the active layer includes: attaching the flexible backing film to the side of the first electrode layer away from the piezoelectric layer; and attaching the flexible matching layer film to the side of the second electrode layer away from the piezoelectric layer.

[0009] In one embodiment, the preparation of the first electrode layer, the piezoelectric layer, and the second electrode layer stacked sequentially includes: preparing a first mask, a second mask, and obtaining the piezoelectric layer; depositing a first preset metal on the first mask to obtain the first electrode layer; depositing a second preset metal on the second mask to obtain the second electrode layer; and attaching the first electrode layer and the second electrode layer to two opposite sides of the piezoelectric layer, respectively.

[0010] In one embodiment, the preparation of the first and second masks includes: obtaining a first flexible mask, etching the first flexible mask into a first preset serpentine pattern to obtain the first mask; obtaining a second flexible mask, etching the second flexible mask into a second preset serpentine pattern to obtain the second mask.

[0011] In one embodiment, the first electrode layer is an excitation electrode layer, and the second electrode layer is a common ground electrode layer.

[0012] In one embodiment, the first acoustic impedance monomer includes at least one of tungsten and tungsten oxide.

[0013] In one embodiment, the second acoustic impedance monomer includes at least one of quartz, aluminum, and alumina.

[0014] An ultrasonic transducer includes: an active layer for generating ultrasonic signals; a backing layer attached to a first side of the active layer, the backing layer being a flexible backing layer film made based on a first mixed solution containing a preset polymer and a first acoustic impedance monomer; and a matching layer attached to a second side of the active layer, the matching layer being a flexible matching layer film made based on a second mixed solution containing the preset polymer and a second acoustic impedance monomer, wherein the first side and the second side of the active layer are opposite to each other.

[0015] In one embodiment, the active layer includes: a first electrode layer, a second electrode layer, and a piezoelectric layer. The first electrode layer and the second electrode layer are respectively attached to two opposite sides of the piezoelectric layer. The side of the first electrode layer away from the piezoelectric layer is the first side of the active layer, and the side of the second electrode layer away from the piezoelectric layer is the second side of the active layer.

[0016] In one embodiment, the piezoelectric layer includes: a flexible substrate; and a plurality of ultrasonic elements, which are spaced apart and bonded to the flexible substrate for transmitting ultrasonic signals toward the side of the flexible substrate near the matching layer.

[0017] The above-described method for fabricating an ultrasonic transducer involves first preparing a first mixed solution containing a predetermined polymer and a first acoustic impedance monomer. Then, a flexible backing layer film is prepared based on the first mixed solution. Next, a second mixed solution containing the predetermined polymer and a second acoustic impedance monomer is prepared. Then, a flexible matching layer film is prepared based on the second mixed solution. Since both the flexible backing layer film and the flexible matching layer film are prepared from the mixed solution, they possess a certain degree of elasticity, allowing for better adhesion to the imaging area. An active layer is then prepared; the active layer is the film structure in the ultrasonic transducer that emits ultrasonic signals. Finally, the flexible backing layer film and the flexible matching layer film are attached to the two opposite sides of the active layer to obtain the ultrasonic transducer. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a method for fabricating an ultrasonic transducer in one embodiment;

[0020] Figure 2 This is a flowchart of a method for fabricating an ultrasonic transducer in another embodiment;

[0021] Figure 3 This is a flowchart of a method for fabricating an ultrasonic transducer in yet another embodiment;

[0022] Figure 4 This is a flowchart of a method for preparing an active layer in one embodiment;

[0023] Figure 5 This is a flowchart of a method for preparing a photomask in one embodiment;

[0024] Figure 6 This is a schematic diagram of the first mask in one embodiment;

[0025] Figure 7 This is a schematic diagram of the second mask in one embodiment;

[0026] Figure 8 This is a schematic diagram of the structure of an ultrasonic transducer in one embodiment;

[0027] Figure 9 This is a schematic diagram of the active layer structure in one embodiment;

[0028] Figure 10This is a schematic diagram of the ultrasonic transducer in another embodiment;

[0029] Figure 11 This is a schematic diagram of the piezoelectric layer structure in one embodiment;

[0030] Figure 12 This is an impedance phase curve of an ultrasonic element in one embodiment;

[0031] Figure 13 This is an echo signal diagram of an ultrasonic element in one embodiment.

[0032] Explanation of reference numerals in the attached figures: 10-first electrode, 20-second electrode, 30-third electrode, 40-fourth electrode, 50-fifth electrode, 60-backing layer, 70-active layer, 80-matching layer, 71-first electrode layer, 72-second electrode layer, 73-piezoelectric layer, 91-first encapsulation layer, 92-second encapsulation layer, 731-flexible substrate, 732-ultrasonic vibrator. Detailed Implementation

[0033] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0035] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another.

[0036] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. Furthermore, in the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if there is transmission of electrical signals or data between the connected objects.

[0037] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0038] In one embodiment, such as Figure 1 As shown, a method for manufacturing an ultrasonic transducer is provided, the method comprising:

[0039] Step S100: Prepare a first mixed solution containing a preset polymer and a first acoustic impedance monomer.

[0040] Specifically, a hot-melt, highly elastic polymer monomer powder is dissolved in an organic solvent, and a first acoustic impedance monomer powder is added. The solution is then heated at a high temperature so that both the polymer monomer powder and the first acoustic impedance monomer powder dissolve in the organic solvent, resulting in a first mixed solution.

[0041] For example, the preset polymer can be made of polyimide (PI), polyethylene terephthalate (PET), liquid crystal polymer (LCP), or rubber, etc. Any polymer that is heat-melting and highly elastic can be used.

[0042] Step S110: Based on the first mixed solution, prepare a flexible backing layer film.

[0043] Specifically, the first mixed solution is coated onto a pre-designed rectangular substrate, which is then placed on a spin coater to form a film using a spin coating method. During the spin coating process, the rotation speed and spin coating time can be adjusted as needed, for example, adjusting the rotation speed to 35,000 rpm and the time to 45 seconds. By adjusting the spin coating speed and time, the thickness and uniformity of the resulting film can be adjusted. After obtaining the film, it is annealed at high temperature, and then the film is peeled off from the substrate to obtain the flexible backing layer film.

[0044] For example, the first acoustic impedance monomer includes at least one of tungsten and tungsten oxide. Therefore, due to the material properties of the first acoustic impedance monomer, the flexible backing film prepared using a first mixed solution containing the first acoustic impedance monomer can absorb ultrasonic signals. Thus, it can serve as a backing layer for an ultrasonic transducer, absorbing ultrasonic signals and preventing them from propagating in undesirable directions. It also reduces interference to ultrasonic imaging caused by multiple reflections of the ultrasonic signal within the ultrasonic transducer. Furthermore, it increases the damping of the ultrasonic transducer, resulting in a narrower transmitted pulse and a more concentrated ultrasonic signal, thereby improving resolution.

[0045] Step S120: Prepare a second mixed solution containing a preset polymer and a second acoustic impedance monomer.

[0046] Specifically, a hot-melt, highly elastic polymer monomer powder is dissolved in an organic solvent, and a second acoustic impedance monomer powder is added. The solution is then heated at a high temperature so that both the polymer monomer powder and the second acoustic impedance monomer powder dissolve in the organic solvent, resulting in a second mixed solution.

[0047] For example, the preset polymer can be made of polyimide (PI), polyethylene terephthalate (PET), liquid crystal polymer (LCP), or rubber, etc. Any polymer that is heat-melting and highly elastic can be used.

[0048] Step S130: Based on the second mixed solution, prepare a flexible matching layer film.

[0049] Specifically, the second mixed solution is coated onto a pre-designed rectangular substrate, which is then placed on a spin coater to form a film using a spin coating method. During the spin coating process, the rotation speed and time can be adjusted as needed, for example, adjusting the rotation speed to 35,000 rpm and the time to 45 seconds. By adjusting the spin coating speed and time, the thickness and uniformity of the resulting film can be adjusted. After obtaining the film, it is annealed at high temperature, and then the film is peeled off from the substrate to obtain the flexible matching layer film.

[0050] For example, the second acoustic impedance monomer includes at least one of quartz, aluminum, and alumina. Due to the material properties of the second acoustic impedance monomer, the flexible matching layer film prepared using a second mixed solution containing the second acoustic impedance monomer can conduct ultrasonic signals, thereby enabling the ultrasonic signals to propagate. It can effectively adjust the difference in acoustic impedance between different film layers, reducing the loss of ultrasonic signals during propagation, improving the quality of ultrasonic signals, and thus improving the quality of ultrasonic imaging. The specific material used for the matching layer needs to be determined according to actual requirements. Because the difference in acoustic impedance between the active layer of the ultrasonic transducer and the object to be imaged is large, a matching layer is needed to coordinate and buffer the signal, reducing image distortion caused by rapid changes in acoustic impedance between the active layer and the object to be imaged during ultrasonic signal propagation.

[0051] For example, the rectangular substrate has a length of 3-8cm and a width of 1-5cm.

[0052] Step S140: Prepare the active layer.

[0053] Specifically, the active layer includes an array of multiple ultrasonic elements that can generate vibrations to emit ultrasonic signals, receive ultrasonic signals reflected back from the object to be imaged, and transmit the reflected ultrasonic signals to the outside in the form of electrical signals, thereby obtaining an ultrasonic image.

[0054] In step S150, the flexible backing layer film and the flexible matching layer film are respectively attached to the two sides opposite to the active layer.

[0055] Specifically, the flexible backing layer film and the flexible matching layer film are respectively attached to the two sides opposite to the active layer using conductive silver paste.

[0056] For example, the conductive silver paste can be a silver-based epoxy resin or polyurethane.

[0057] In this embodiment, a first mixed solution containing a preset polymer and a first acoustic impedance monomer is first prepared. Then, a flexible backing layer film is prepared based on the first mixed solution. Next, a second mixed solution containing the preset polymer and a second acoustic impedance monomer is prepared. Then, a flexible matching layer film is prepared based on the second mixed solution. Since both the flexible backing layer film and the flexible matching layer film are prepared from the mixed solution, they are both films with a certain degree of elasticity, thus enabling better adhesion to the imaging area. Next, an active layer is prepared, which is the film structure in the ultrasonic transducer capable of emitting ultrasonic signals. Finally, the flexible backing layer film and the flexible matching layer film are attached to the two opposite sides of the active layer to obtain the ultrasonic transducer.

[0058] In one embodiment, such as Figure 2As shown, the fabrication method of the ultrasonic transducer also includes:

[0059] Step S200: Prepare a third mixed solution containing a preset polymer.

[0060] Specifically, a polymer monomer powder with high heat-melting elasticity is dissolved in an organic solvent, and then the solution is heated at a high temperature to completely dissolve the polymer monomer powder in the organic solvent, thus obtaining a third mixed solution.

[0061] Step S220: Based on the third mixed solution, prepare the first encapsulation layer film and the second encapsulation layer film.

[0062] Specifically, the third mixed solution is coated onto a pre-designed rectangular substrate, which is then placed on a spin coater to form a film using a spin coating method. During spin coating, the rotation speed and time can be adjusted as needed, for example, adjusting the rotation speed to 35,000 rpm and the time to 45 seconds. By adjusting the spin coating speed and time, the thickness and uniformity of the resulting film can be adjusted. After obtaining the film, it is annealed at high temperature, and then the film is peeled off from the substrate to obtain the first encapsulation layer film. Repeating the above steps once yields the second encapsulation layer film.

[0063] Step S240: A flexible backing film is formed on the first encapsulation layer film.

[0064] Specifically, the first mixed solution is coated onto the first encapsulation layer film, and then placed on a spin coater to form a film using a spin coating method. During the spin coating process, the rotation speed and spin coating time can be adjusted as needed, for example, adjusting the rotation speed to 35,000 rpm and the time to 45 seconds. By adjusting the spin coating speed and time, the thickness and uniformity of the resulting film can be adjusted. After obtaining the film, high-temperature annealing is performed to form a flexible backing layer film on the first encapsulation layer film.

[0065] Step S260: A flexible matching layer film is formed on the second encapsulation layer film.

[0066] Specifically, the second mixed solution is coated onto the second encapsulation layer film, and then placed on a spin coater to form a film using a spin coating method. During the spin coating process, the rotation speed and spin coating time can be adjusted as needed, for example, adjusting the rotation speed to 35,000 rpm and the time to 45 seconds. By adjusting the spin coating speed and time, the thickness and uniformity of the resulting film can be adjusted. After obtaining the film, high-temperature annealing is performed to form a flexible matching layer film on the second encapsulation layer film.

[0067] In this embodiment, a first encapsulation layer film and a second encapsulation layer film are prepared using a third mixed solution containing a preset polymer. A flexible backing layer film is then formed on the first encapsulation layer film, and a flexible matching layer film is formed on the second encapsulation layer film. Since the same preset polymer is dissolved in the first, second, and third mixed solutions, the intermolecular forces ensure a smooth, gapless fit between the first encapsulation layer film and the flexible backing layer film, resulting in a closer fit. Similarly, the intermolecular forces ensure a smooth, gapless fit between the second encapsulation layer film and the flexible matching layer film, further enhancing their fit. Furthermore, because the encapsulation layer of the ultrasonic transducer is also made of a flexible film, it is elastic and flexible, allowing for better conformation to different curved surfaces and adaptability to various shapes of imaging sites. This further improves the fit between the ultrasonic transducer and the imaging site, enabling the acquisition of higher quality ultrasonic images.

[0068] In one embodiment, such as Figure 3 As shown, step S140, preparing the active layer includes:

[0069] Step S300: Prepare a first electrode layer, a piezoelectric layer, and a second electrode layer that are stacked sequentially.

[0070] Specifically, the active layer consists of a first electrode layer, a piezoelectric layer, and a second electrode layer stacked sequentially. The first electrode layer is the excitation electrode layer, used to connect to an external power source, and the second electrode layer is the ground electrode layer, used for grounding. This creates a circuit between the first and second electrode layers. Applying a driving signal to the first and second electrode layers drives multiple ultrasonic elements in the piezoelectric layer to vibrate, thereby generating ultrasonic signals.

[0071] Step S150 involves attaching the flexible backing layer film and the flexible matching layer film to the two opposite sides of the active layer, including:

[0072] Step S320: Attach the flexible backing film to the side of the first electrode layer away from the piezoelectric layer.

[0073] Specifically, the flexible backing layer film is attached to the side of the first electrode layer away from the piezoelectric layer using conductive silver paste.

[0074] Step S340: Attach the flexible matching layer film to the side of the second electrode layer away from the piezoelectric layer.

[0075] Specifically, the flexible matching layer film is attached to the side of the second electrode layer away from the piezoelectric layer using conductive silver paste. This achieves the attachment of the flexible backing layer film and the flexible matching layer film to two opposite sides of the active layer.

[0076] In this embodiment, the active layer is composed of a first electrode layer, a piezoelectric layer, and a second electrode layer stacked in sequence. After the first electrode layer, the piezoelectric layer, and the second electrode layer are stacked in sequence, a flexible backing film is attached to the side of the first electrode layer away from the piezoelectric layer, and a flexible matching layer film is attached to the side of the second electrode layer away from the piezoelectric layer, thus completing the fabrication of the ultrasonic transducer.

[0077] In one embodiment, such as Figure 4 As shown, step S300 involves fabricating a first electrode layer, a piezoelectric layer, and a second electrode layer that are sequentially stacked. This includes:

[0078] Step S400: Prepare the first mask, the second mask, and obtain the piezoelectric layer.

[0079] Specifically, the piezoelectric layer is composed of a piezoelectric polymer. The piezoelectric polymer satisfies suitable acoustic properties, such as an acoustic impedance between 2.5 M Nayl and 5 M Nayl. Materials include PVDF (polyvinylidene fluoride), PVDF-TrFe (polyvinylidene fluoride-trifluoroethylene), PTFE (polytetrafluoroethylene), PVDC (polyvinyl chloride), and DIPAB (diisopropylamine bromide). Examples of PVDF copolymers include PVDF-TrFe with molar ratios of 60:40, 70:30, 80:20, and 90:10.

[0080] Preferably, the piezoelectric layer is made of a 1-3 type composite piezoelectric ceramic. This 1-3 composite piezoelectric ceramic is formed by parallel arrangement of one-dimensionally connected piezoelectric ceramic phases within a three-dimensionally connected polymer. By adding the polymer, the ceramic's weaknesses in strength and brittleness are effectively reduced, and the lateral coupling of the ceramic is decreased, increasing the longitudinal electromechanical conversion efficiency of the composite material. It also has low acoustic impedance, making it easy to impedance match with media such as water and skin. Furthermore, due to its low dielectric constant and small electrostatic capacitance, a higher input impedance is required when the transducer is operating, resulting in higher receiving voltage sensitivity. Additionally, because the polymer has significant attenuation and a low quality factor, it is particularly suitable for fabricating broadband narrow-pulse transducers. The 1-3 type interlocking structure suppresses the lateral vibration of the piezoelectric layer, ensuring that the vibration of the piezoelectric layer primarily generates longitudinal ultrasonic vibrations, making the generated ultrasonic signals more pronounced.

[0081] Step S410: Deposit a first preset metal on the first mask to obtain a first electrode layer.

[0082] Specifically, a vacuum deposition method is used for deposition, in which a first preset metal is heated under vacuum conditions, causing the first preset metal to evaporate and condense onto a first mask, thus completing the deposition. Alternatively, magnetron sputtering can also be used for deposition.

[0083] In step S420, a second preset metal is deposited on the second mask to obtain a second electrode layer.

[0084] Specifically, a vacuum deposition method is used for deposition, in which a second preset metal is heated under vacuum conditions, causing the second preset metal to evaporate and condense onto a second mask, thus completing the deposition. Alternatively, magnetron sputtering can also be used for deposition.

[0085] For example, the first preset metal and the second preset metal may be one or more of the following: copper, gold, silver, aluminum, tungsten, tantalum, cobalt, nickel, indium, beryllium, brass, iron, platinum, titanium, tungsten carbide, molybdenum oxide, chromium carbide, tantalum carbide, PGS graphite sheets obtained by graphitizing polymer films, graphite, carbon nanotubes, aluminum nitride, boron nitride, silicon carbide, beryllium oxide, magnesium oxide, and zinc oxide, or other conductive materials.

[0086] Step S430: The first electrode layer and the second electrode layer are attached to the two opposite sides of the piezoelectric layer, respectively.

[0087] Specifically, the first electrode layer and the second electrode layer are attached to two opposite sides of the piezoelectric layer using conductive silver paste to complete the fabrication of the active layer.

[0088] In this embodiment, a first electrode layer and a second electrode layer are obtained by depositing metal films on a first mask and a second mask. Then, the first electrode layer and the second electrode layer are respectively attached to two opposite sides of the piezoelectric layer to obtain an active layer.

[0089] In one embodiment, such as Figure 5 As shown, step S400 involves fabricating a first mask, a second mask, and obtaining a piezoelectric layer. This includes:

[0090] Step S500: Obtain the first flexible mask and etch the first flexible mask into a first preset serpentine pattern to obtain the first mask.

[0091] Specifically, the first flexible mask is etched into a first preset serpentine pattern by photolithography to obtain the first mask.

[0092] For example, a first mask etched with a first preset serpentine pattern, such as Figure 6As shown, the first photomask includes a first electrode 10, a second electrode 20, and a third electrode 30. The first electrode 10 is used to connect to an external flexible circuit board to transmit ultrasonic signals to the outside in the form of electrical signals, thereby obtaining an ultrasonic image. The second electrode 20 is used to adhere to and connect to a piezoelectric layer to apply an excitation signal to the piezoelectric layer and acquire the ultrasonic signals of the piezoelectric layer, driving the piezoelectric layer to vibrate. The third electrode 30 is used to connect to the second photomask to form a circuit. Furthermore, the flexible photomask connecting each pair of electrodes is a serpentine curved circuit, which can fit other flexible structures of the ultrasonic transducer, facilitating stretching when the ultrasonic transducer is attached to the object to be imaged, thereby allowing the ultrasonic transducer to better fit the object to be imaged.

[0093] Step S520: Obtain the second flexible mask and etch the second flexible mask into a second preset serpentine pattern to obtain the second mask.

[0094] Specifically, the second flexible mask is etched into a second preset serpentine pattern by photolithography to obtain the second mask.

[0095] For example, a second mask etched with a second preset serpentine pattern, such as Figure 7 As shown, the second photomask includes a fourth electrode 40 and a fifth electrode 50. The fourth electrode 40 is used to attach the piezoelectric layer, and the fifth electrode 50 is used to connect with the third electrode 30.

[0096] In this embodiment, by etching both the first and second masks into corresponding preset serpentine patterns, it is possible to fit other flexible structures of the ultrasonic transducer, which facilitates stretching when the ultrasonic transducer is attached to the object to be imaged, thereby enabling the ultrasonic transducer to better fit the object to be imaged.

[0097] In one embodiment, such as Figure 8 As shown, an ultrasonic transducer is provided, comprising: an active layer 70, a backing layer 60, and a matching layer 80. Wherein:

[0098] Active layer 70 is used to generate ultrasonic signals.

[0099] The backing layer 60 is attached to the first side of the active layer 70. The backing layer 60 is a flexible backing layer 60 film made based on a first mixed solution containing a preset polymer and a first acoustic impedance monomer.

[0100] Matching layer 80 is attached to the second side of active layer 70. Matching layer 80 is a flexible matching layer 80 film made based on a second mixed solution containing a preset polymer and a second acoustic impedance monomer. The first side and the second side of active layer 70 are opposite to each other.

[0101] In this embodiment, the backing layer 60 is a flexible backing layer 60 film made from a first mixed solution containing a preset polymer and a first acoustic impedance monomer, and the matching layer 80 is a flexible matching layer 80 film made from a second mixed solution containing a preset polymer and a second acoustic impedance monomer. Since both the flexible backing layer 60 film and the flexible matching layer 80 film are prepared from mixed solutions, they are both films with a certain degree of elasticity, thus enabling them to better fit the area to be imaged. The active layer 70 is a film structure in the ultrasonic transducer that can emit ultrasonic signals. The ultrasonic transducer is then prepared by attaching the flexible backing layer 60 film and the flexible matching layer 80 film to the two opposite sides of the active layer 70. The ultrasonic transducer prepared by the method of this application, since both the backing layer 60 and the matching layer 80 are flexible films, can fit different curved surfaces and adapt to various shapes of areas to be imaged, thereby improving the fit between the ultrasonic transducer and the area to be imaged and enabling the acquisition of higher quality ultrasonic images.

[0102] In one embodiment, such as Figure 9 As shown, the active layer 70 includes: a first electrode layer 71, a second electrode layer 72, and a piezoelectric layer 73. The first electrode layer 71 and the second electrode layer 72 are respectively attached to two opposite sides of the piezoelectric layer 73. The side of the first electrode layer 71 away from the piezoelectric layer 73 is the first side of the active layer 70, and the side of the second electrode layer 72 away from the piezoelectric layer 73 is the second side of the active layer 70.

[0103] In this embodiment, the active layer 70 includes a first electrode layer 71, a piezoelectric layer 73, and a second electrode layer 72 stacked sequentially.

[0104] For example, such as Figure 10 As shown, the ultrasonic transducer also includes a first encapsulation layer 91 and a second encapsulation layer 92. The first encapsulation layer 91 is attached to the outside of the backing layer 60, and the second encapsulation layer 92 is attached to the outside of the mating layer 80. The first encapsulation layer 91 and the second encapsulation layer 92 together constitute the external encapsulation structure of the ultrasonic transducer. By setting the first encapsulation layer 91 and the second encapsulation layer 92, the internal structure of the ultrasonic transducer can be protected, while making the appearance of the ultrasonic transducer simpler.

[0105] In one embodiment, such as Figure 11 As shown, the piezoelectric layer 73 includes a flexible substrate 731 and a plurality of ultrasonic elements 732. Specifically, the flexible substrate 731 also has a built-in driving circuit for an ultrasonic transducer, which can drive the plurality of ultrasonic elements 732 to vibrate. The plurality of ultrasonic elements 732 are bonded to the flexible substrate 731 at intervals and are used to emit ultrasonic signals to the side of the flexible substrate 731 near the matching layer 80.

[0106] Specifically, the ultrasonic transducer 732 is bonded to the flexible substrate 731 using conductive silver paste. When the flexible substrate 731 is bent, the distance between the first ends of any two adjacent ultrasonic transducers 732 decreases, and the distance between the second ends of any two adjacent ultrasonic transducers 732 increases. At this time, the surface formed by the first ends of the multiple ultrasonic transducers 732 is an arc surface, which can fit well with the object to be imaged.

[0107] In this embodiment, by setting the piezoelectric layer 73 to include multiple ultrasonic elements 732 fixed on the flexible substrate 731, the piezoelectric layer 73 can be bent arbitrarily and fit well with the object to be imaged, thereby enabling high-quality transmission and reception of ultrasonic signals and obtaining high-quality ultrasonic images.

[0108] For example, such as Figure 12 The figure shows the impedance-phase curve of the ultrasonic element. It can be seen from the figure that the center frequency of the curve is about 7.5MHz, which can provide good spatial resolution. The low impedance value also indicates low power consumption.

[0109] For example, such as Figure 13 The figure shows the test echo signal diagram of the ultrasonic element. It can be seen from the figure that the amplitude of the echo signal is relatively high, thus having a good signal-to-noise ratio, which can meet the requirements of ultrasonic detection.

[0110] It should be understood that, although Figures 1-5 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order requirement for the execution of these steps; they can be executed in other orders. Furthermore, Figures 1-5 At least some of the steps in the process may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but may be executed at different times. The execution order of these steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least some of the steps or stages in other steps.

[0111] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0112] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0113] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for manufacturing an ultrasonic transducer, characterized in that, The method includes: Prepare a first mixed solution containing a preset polymer and a first acoustic impedance monomer; The first mixed solution was coated onto a preset substrate by spin coating, and after high-temperature annealing, it was peeled off to obtain a flexible backing layer film. Prepare a second mixed solution containing the preset polymer and the second acoustic impedance monomer; The second mixed solution was coated onto a preset substrate by spin coating, and then peeled off after high-temperature annealing to obtain a flexible matching layer film. Prepare a third mixed solution containing the predetermined polymer; Based on the third mixed solution, a first encapsulation layer film and a second encapsulation layer film are prepared; The flexible backing layer film is formed on the first encapsulation layer film; the flexible matching layer film is formed on the second encapsulation layer film; An active layer is prepared, the active layer comprising a first electrode layer, a piezoelectric layer, and a second electrode layer stacked sequentially; The flexible backing film and the flexible matching layer film are respectively attached to the two opposite sides of the active layer. The fabrication of the first electrode layer, piezoelectric layer, and second electrode layer, which are sequentially stacked, includes: Obtain a first flexible mask, and etch the first flexible mask into a first preset serpentine pattern to obtain the first mask; Obtain a second flexible mask, and etch the second flexible mask into a second preset serpentine pattern to obtain the second mask; Obtaining a piezoelectric layer; The first electrode layer is obtained by depositing a first preset metal on the first mask. The second electrode layer is obtained by depositing a second preset metal on the second mask. The first electrode layer and the second electrode layer are respectively attached to the two opposite sides of the piezoelectric layer.

2. The method for preparing an ultrasonic transducer according to claim 1, characterized in that, The step of attaching the flexible backing layer film and the flexible matching layer film to the two opposite sides of the active layer includes: The flexible backing film is attached to the side of the first electrode layer away from the piezoelectric layer; The flexible matching layer film is attached to the side of the second electrode layer away from the piezoelectric layer.

3. The method for preparing an ultrasonic transducer according to claim 1, characterized in that, The first mask includes a first electrode, a second electrode, and a third electrode; the second mask includes a fourth electrode and a fifth electrode.

4. The method for preparing an ultrasonic transducer according to claim 1, characterized in that, The first electrode layer is an excitation electrode layer, and the second electrode layer is a common ground electrode layer.

5. The method for manufacturing an ultrasonic transducer according to any one of claims 1-4, characterized in that, The first acoustic impedance monomer includes at least one of tungsten and tungsten oxide.

6. The method for manufacturing an ultrasonic transducer according to any one of claims 1-4, characterized in that, The second acoustic impedance monomer includes at least one of quartz, aluminum, and alumina.

7. An ultrasonic transducer, characterized in that, include: An active layer is used to generate ultrasonic signals; the active layer includes a first electrode layer, a piezoelectric layer, and a second electrode layer stacked sequentially. The first electrode layer is an electrode layer formed by depositing a first preset metal on a first mask; the first mask is a first flexible mask etched with a first preset serpentine pattern. The second electrode layer is an electrode layer formed by depositing a second preset metal on a second mask; the second mask is a second flexible mask etched with a second preset serpentine pattern. A piezoelectric layer, wherein the first electrode layer and the second electrode layer are respectively attached to two opposite sides of the piezoelectric layer; A backing layer is attached to the first side of the active layer. The backing layer is a flexible backing layer film made based on a first mixed solution containing a preset polymer and a first acoustic impedance monomer. The first mixed solution is coated onto a predetermined substrate by spin coating, and then peeled off after high-temperature annealing to obtain a flexible backing layer film; wherein the flexible backing layer film is formed on a first encapsulation layer film, and the first encapsulation layer film is prepared from a third mixed solution containing the predetermined polymer. A matching layer is attached to the second side of the active layer. The matching layer is a flexible matching layer film made based on a second mixed solution containing the preset polymer and the second acoustic impedance monomer. The second mixed solution is coated onto a preset substrate by spin coating, and then peeled off after high-temperature annealing to obtain the flexible matching layer film. The flexible matching layer film is formed on a second encapsulation layer film, which is prepared by a third mixed solution containing the preset polymer. The first and second sides of the active layer are opposite to each other.

8. The ultrasonic transducer according to claim 7, characterized in that, The side of the first electrode layer away from the piezoelectric layer is the first side of the active layer, and the side of the second electrode layer away from the piezoelectric layer is the second side of the active layer.

9. The ultrasonic transducer according to claim 8, characterized in that, The piezoelectric layer includes: Flexible substrate; Multiple ultrasonic elements are bonded at intervals to the flexible substrate for transmitting ultrasonic signals toward the side of the flexible substrate near the matching layer.

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