CN113165017B - Ultrasonic transducer, information acquisition element and electronic equipment - Google Patents
Ultrasonic transducer, information acquisition element and electronic equipment Download PDFInfo
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- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
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Abstract
An ultrasonic transducer, an information acquisition element, and an electronic apparatus, the ultrasonic transducer (10) comprising: a first electrode (101), a second electrode (102), a piezoelectric layer (103), and a support layer (104); the piezoelectric layer (103) is made of a piezoelectric material; the first electrode (101) and the second electrode (102) are respectively fixed above and below the piezoelectric layer (103); the horizontal distance between the first electrode (101) and the second electrode (102) is greater than or equal to a preset distance; the supporting layer (104) is fixed below the piezoelectric layer (103), the supporting layer (104) is provided with an opening (1041) with an upward direction, the opening (1041) is a blind hole or a through hole, and the piezoelectric layer (103) covers the opening, so that the sensitivity of the ultrasonic transducer (10) can be improved.
Description
Technical Field
The embodiment of the application relates to the technical field of electronic information, in particular to an ultrasonic transducer, an information acquisition element and electronic equipment.
Background
The ultrasonic transducer is a device for converting sound energy and electric energy into each other, and the two ends of a piezoelectric material in the ultrasonic transducer can generate a voltage difference when the piezoelectric material deforms; the piezoelectric material can deform when a voltage difference exists between the two ends. By utilizing such characteristics of the piezoelectric material, the interconversion of mechanical vibration and alternating current can be achieved.
However, the conventional Ultrasonic Transducer has a large volume, and cannot be used in some portable mobile terminals, and with the development of Micro-manufacturing technology, the MEMS Ultrasonic Transducer (MUT) based on Micro Electro Mechanical System (MEMS) technology has a reduced volume on the basis of meeting certain performance requirements, but the MEMS Ultrasonic Transducer has a lower sensitivity compared with the conventional Ultrasonic Transducer because the volume of the MEMS Ultrasonic Transducer is reduced.
Disclosure of Invention
In view of the above, one of the technical problems to be solved by the embodiments of the present invention is to provide an ultrasound transducer, an information collecting element and an electronic device, so as to overcome the defect of low sensitivity of the ultrasound transducer in the prior art.
In a first aspect, an embodiment of the present application provides an ultrasound transducer, including: a first electrode, a second electrode, a piezoelectric layer, and a support layer;
the piezoelectric layer is made of piezoelectric material; the first electrode and the second electrode are respectively fixed above and below the piezoelectric layer; the horizontal distance between the first electrode and the second electrode is greater than or equal to a preset distance, and the preset distance is greater than 0;
the supporting layer is fixed in the below of piezoelectric layer, and the supporting layer is provided with the ascending trompil of direction, and the trompil is blind hole or through-hole, and the piezoelectric layer covers on the trompil.
Optionally, in one embodiment of the present application, the piezoelectric layer is in contact with an edge of the opening of the upper surface of the support layer, and the second electrode is disposed between the piezoelectric layer and the support layer.
Optionally, in an embodiment of the present application, an upper surface of the second electrode is in contact with a lower surface of the piezoelectric layer, and the lower surface of the second electrode is in contact with an upper surface around the opening of the support layer.
Optionally, in one embodiment of the present application, the first electrode and the second electrode are plate electrodes.
Optionally, in an embodiment of the present application, the second electrode is a ring-shaped plate electrode; the projection of the first electrode on the second electrode is located within the ring shape of the second electrode.
Optionally, in an embodiment of the present application, the opening provided in the support layer is a cylindrical hollow region, the second electrode is in a circular ring shape, and a ratio of a radius of an inner ring of the second electrode to a radius of the opening is within a preset range.
Optionally, in an embodiment of the present application, the inner ring radius of the second electrode is equal to the radius of the aperture.
Optionally, in an embodiment of the present application, the ultrasound transducer further includes a third electrode on the same side of the piezoelectric layer as the second electrode, the third electrode facing the first electrode.
Optionally, in an embodiment of the present application, the third electrode is separated from the second electrode.
Optionally, in an embodiment of the present application, the second electrode is disposed around a third electrode, and the third electrode is disposed at the opening of the support layer.
Optionally, in an embodiment of the present application, the ultrasonic transducer further includes a vibration film layer, and the vibration film layer is fixed between the support layer and the piezoelectric layer.
Optionally, in one embodiment of the present application, the diaphragm layer is made of an insulating material.
In a second aspect, embodiments of the present application provide an information acquisition element comprising an ultrasound transducer as described in the first aspect or any one of the embodiments of the first aspect.
Optionally, in an embodiment of the present application, the information collecting element is a microphone, an ultrasonic radar, an ultrasonic imaging device, an ultrasonic fingerprint collecting device or a proximity sensor.
In a third aspect, embodiments of the present application provide an electronic device, including an ultrasound transducer as described in the first aspect or any one of the embodiments of the first aspect.
Optionally, in an embodiment of the application, the electronic device comprises an ultrasound transducer array, the ultrasound transducer array being an array of at least two ultrasound transducers as described in the first aspect or in any of the embodiments of the first aspect.
The ultrasonic transducer, the information acquisition component and the electronic equipment provided by the embodiment of the application have the advantages that the first electrode and the second electrode are respectively fixed above and below the piezoelectric layer, the horizontal distance between the first electrode and the second electrode is larger than or equal to the preset distance, and because the horizontal distance between the two electrodes is larger than or equal to the preset distance, under the condition that the electric charge amount is unchanged, the capacitance is reduced, the voltage is increased, and the sensitivity is improved.
Drawings
Some specific embodiments of the present application will be described in detail hereinafter by way of illustration and not limitation with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:
fig. 1 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application;
fig. 2 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application;
fig. 3 is a schematic diagram illustrating an effect of a first electrode and a second electrode provided in an embodiment of the present application;
FIG. 4a is a schematic diagram illustrating a top view of an electrode shape according to an embodiment of the present disclosure;
FIG. 4b is a schematic diagram illustrating a top view of an electrode shape according to an embodiment of the present disclosure;
FIG. 4c is a schematic diagram illustrating a top view of an electrode shape according to an embodiment of the present disclosure;
FIG. 5 is a graph of a ratio k versus sensitivity mapping provided by an embodiment of the present application;
fig. 6 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application;
fig. 7 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application;
fig. 8 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application;
FIG. 9 is a schematic diagram of a fingerprint acquisition system according to an embodiment of the present application;
FIG. 10 is a schematic longitudinal sectional view of an ultrasonic fingerprint acquisition provided by an embodiment of the present application;
FIG. 11 is a schematic longitudinal cross-sectional view of a proximity sensor according to an embodiment of the present application;
fig. 12 is a block diagram of an electronic device according to an embodiment of the present application.
Detailed Description
It is not necessary for any particular embodiment of the invention to achieve all of the above advantages at the same time.
In order to make those skilled in the art better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application shall fall within the scope of the protection of the embodiments in the present application.
The following further describes specific implementations of embodiments of the present application with reference to the drawings of the embodiments of the present application.
The first embodiment,
Fig. 1 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application; as shown in fig. 1, the ultrasonic transducer 10 includes: a first electrode 101, a second electrode 102, a piezoelectric layer 103, and a support layer 104;
the piezoelectric layer 103 is made of a piezoelectric material; the first electrode 101 and the second electrode 102 are fixed above and below the piezoelectric layer 103, respectively; the horizontal distance between the first electrode 101 and the second electrode 102 is greater than or equal to a preset distance, and the preset distance is greater than 0;
the support layer 104 is fixed below the piezoelectric layer 103, and the support layer is provided with an upward opening which is a blind hole or a through hole, and the piezoelectric layer covers the opening.
Fig. 1 illustrates the opening 1041 as a blind hole, which does not mean that the present application is limited thereto. As shown in fig. 2, fig. 2 is a schematic longitudinal sectional view of an ultrasonic transducer provided in an embodiment of the present application, and fig. 2 shows a case where the opening 1041 is a through hole. The support layer 104 is provided with openings 1041 so that the piezoelectric layer 103 can vibrate, thereby performing acousto-electric conversion.
The support layer 104 acts as an edge support for the piezoelectric layer 103. Optionally, in one embodiment of the present application, the piezoelectric layer 103 is in edge contact with the opening 1041 on the upper surface of the support layer 104.
Optionally, the second electrode 102 is disposed between the piezoelectric layer 103 and the support layer 104. Further alternatively, the upper surface of the second electrode 102 is in contact with the lower surface of the piezoelectric layer 103, and the lower surface of the second electrode 102 is in contact with the upper surface around the opening 1041 of the support layer 104.
In the present application, a surface of the piezoelectric layer 103 adjacent to the support layer 104 may be defined as a lower surface of the piezoelectric layer 103, another surface may be defined as an upper surface of the piezoelectric layer 103, a side of the upper surface may be defined as an upper side, a side of the lower surface may be defined as a lower side, a direction perpendicular to the upper surface and the lower surface of the piezoelectric layer 103 may be defined as a vertical direction, and a plane parallel to the upper surface and the lower surface of the piezoelectric layer 103 may be defined as a horizontal plane. The upper surface, the lower surface, the vertical direction and the horizontal plane defined herein are defined for illustrating the technology of the present embodiment, and do not represent any limitation, and may also be defined and described in other ways, for example, a surface of the piezoelectric layer 103 close to the supporting layer 104 is defined as an upper surface of the piezoelectric layer 103, and the supporting layer 104 is fixed above the piezoelectric layer 103, which is not limited in this application.
The horizontal distance of the first electrode 101 and the second electrode 102 refers to the shortest distance between the edges of the first electrode 101 and the second electrode 102 obtained regardless of the distance in the vertical direction of the first electrode 101 and the second electrode 102. When a viewing angle from the upper surface to the lower surface of the piezoelectric layer 103 is taken as a top view, a horizontal distance between the first electrode 101 and the second electrode 102 is a distance between the first electrode 101 and the second electrode 102 in the top view. If the up-down direction is taken as a reference direction, the horizontal direction is a direction perpendicular to the reference direction, and the horizontal distance refers to the distance between two electrodes after the two electrodes are projected on the same horizontal plane.
Referring to fig. 3, fig. 3 is a schematic diagram illustrating the effects of a first electrode and a second electrode provided in this embodiment of the present invention, because the first electrode 101 and the second electrode 102 are respectively fixed above and below the piezoelectric layer 103, the two electrodes can be equivalent to a capacitor, and in order to mount the ultrasonic transducer 10 on a portable electronic device 110 (for example, a terminal device such as a smart phone, a tablet computer, etc.), it is necessary to reduce the volume of the piezoelectric layer 103 as much as possible, so the thickness of the piezoelectric layer 103 is small, the vertical distance between the first electrode 101 and the second electrode 102 is small, the capacitance based on the vertical distance between the first electrode 101 and the second electrode 102 is large, and according to the relationship between the charge amount, the capacitance, and the voltage, for example, the formula Q ═ C × V, Q represents the charge amount, C represents the capacitance, V represents the voltage, the charge amount of the two electrodes is constant, the capacitance is large, the smaller the voltage, the smaller the voltage generated based on the vertical distance of the first electrode 101 and the second electrode 102. When the horizontal distance between the first electrode 101 and the second electrode 102 is greater than or equal to the preset distance, the horizontal distance between the first electrode 101 and the second electrode 102 increases, the capacitance based on the horizontal distance between the first electrode 101 and the second electrode 102 is relatively small, and the voltage is relatively large, so that when the horizontal distance between the first electrode 101 and the second electrode 102 is greater than or equal to the preset distance, the voltage generated based on the horizontal distance between the first electrode 101 and the second electrode 102 is relatively large, the detection is easy, and the sensitivity is relatively high.
Optionally, in an embodiment of the present application, the first electrode 101 and the second electrode 102 are flat plate electrodes. The flat plate electrodes are planar electrodes, for example, the first electrode 101 and the second electrode 102 may be disk-shaped electrodes, but this is only an example.
Optionally, in one embodiment of the present application, the second electrode 102 is a ring-shaped flat plate electrode; the projection of the first electrode 101 onto the second electrode 102 is located within the ring shape of the second electrode 102. Here, the shapes of the first electrode 101 and the second electrode 102 are explained in detail, and as shown in fig. 4a, 4b and 4c, fig. 4a to 4c are schematic diagrams illustrating the top view effect of the electrode shape provided by the embodiment of the present application, fig. 4a to 4c illustrate three groups of electrode shapes, in fig. 4a, the first electrode 101 is circular, the second electrode 102 is circular ring-shaped surrounding the first electrode 101, and both the inner ring and the outer ring of the second electrode 102 are circular; in fig. 4b, the first electrode 101 is hexagonal, the second electrode 102 is ring-shaped surrounding the first electrode 101, and both the inner ring and the outer ring of the second electrode 102 are hexagonal; in fig. 4c, the first electrode 101 is square, the second electrode 102 is ring-shaped surrounding the first electrode 101, and both the inner ring and the outer ring of the second electrode 102 are square. In the present application, the second electrode 102 surrounding the first electrode 101 means that the projection of the first electrode 101 on the second electrode 102 is surrounded by the second electrode 102, or the projection of the second electrode 102 on the first electrode 101 surrounds the first electrode 101, meaning that the second electrode 102 surrounds the first electrode 101 in a top view.
Further optionally, in an embodiment of the present application, the opening 1041 of the support layer 104 is a cylindrical hollow region, the second electrode 102 is a circular ring, and a ratio of a radius of an inner ring of the second electrode 102 to a radius of the opening 1041 is within a preset range. Alternatively, the inner ring radius of the second electrode 102 may be equal to the radius of the bore 1041.
Referring to fig. 5, fig. 5 is a graph of a mapping relationship between the radius of the inner ring of the second electrode 102 and the radius of the opening 1041, where the ratio k is Rp/Ri, and the graph of fig. 5 is a graph of the ratio k and the sensitivity provided in this embodiment of the present application, optionally, in the graph of fig. 5, the radius Re of the first electrode 101 and the radius Ri of the opening 1041 satisfy Re being 0.4Ri, and it can be observed from fig. 5 that when the ratio k is less than 1, the sensitivity increases with the increase of the ratio k, when the ratio k is greater than 1, the sensitivity decreases with the increase of the ratio k, and when the ratio k is equal to 1, the sensitivity is maximized, that is, when the radius of the inner ring of the second electrode 102 is equal to the ratio of the radius of the opening 1041, the sensitivity is maximized, and the sensitivity of the ultrasound transducer 10 is further improved. In the present application, the sensitivity may be expressed by a voltage, and a larger voltage indicates a higher sensitivity.
In the process of converting the energy of the mechanical vibration into the electric energy, the piezoelectric layer 103 vibrates under the influence of the mechanical wave, the mechanical wave can be an ultrasonic wave, the piezoelectric layer 103 vibrates, and the deformation caused by the vibration of the piezoelectric layer 103 enables a voltage difference to be generated between the first electrode 101 and the second electrode 102 on the upper surface and the lower surface of the piezoelectric layer 103, and the horizontal distance between the first electrode 101 and the second electrode 102 is larger than or equal to a preset distance, so that the voltage difference is larger, the detection is easy, and the sensitivity of the ultrasonic transducer 10 is higher. Similarly, when the electric energy is converted into the energy of the mechanical vibration, the voltage difference between the two electrodes on the upper and lower surfaces of the piezoelectric layer 103 may deform the piezoelectric layer 103 to cause the vibration, so as to generate the mechanical wave, for example, an ultrasonic wave may be generated.
Fig. 6 is a schematic longitudinal sectional view of an ultrasound transducer provided in an embodiment of the present application, and optionally, in an embodiment of the present application, the ultrasound transducer 10 further includes a third electrode 105, the third electrode 105 is on the same side of the piezoelectric layer 103 as the second electrode 102, and the third electrode 105 faces the first electrode 101.
The third electrode 105 is opposite to the first electrode 101, that is, the third electrode 105 and the first electrode 101 are overlapped in a top view, so that the vibration amplitude of the piezoelectric layer 103 can be enhanced, and the emission efficiency can be improved. The third electrode 105 and the first electrode 101 may be the same size or different sizes.
Optionally, in one embodiment of the present application, the third electrode 105 is separated from the second electrode 102.
Optionally, in an embodiment of the present application, the second electrode 102 is disposed around the third electrode 105, and the third electrode 105 is disposed at the opening of the support layer 104.
Fig. 7 is a schematic longitudinal cross-sectional view of an ultrasonic transducer provided in an embodiment of the present application, and optionally, in an embodiment of the present application, the ultrasonic transducer 10 further includes a diaphragm layer 106, and the diaphragm layer 106 is fixed between the support layer 104 and the piezoelectric layer 103. Fixing the diaphragm layer 106 under the piezoelectric layer 103 can increase the thickness of the entire stack (including the first electrode 101, the second electrode 102, the piezoelectric layer 103, and the diaphragm layer 106), which is more stable in vibration and also improves the lifetime of the piezoelectric layer 103. Alternatively, the laminate may be a planar film or may have a pre-bend.
The vibration film layer 106 is made of a dielectric material, and the vibration film layer 106 can improve the mechanical strength of the lamination, prolong the service life of the device, adjust the rigidity of the lamination, enhance the transmitting/receiving performance, and adjust the thickness of the lamination and the position of a neutral plane to adjust the vibration frequency and the vibration mode. Optionally, in one embodiment of the present application, the diaphragm layer 106 is made of an insulating material. For example, the diaphragm layer 106 may be made of silicon, silicon dioxide, or silicon nitride, or may be formed by stacking several materials, which is not limited in this application.
Optionally, a diaphragm layer 106 and/or a protective layer may also be added over the piezoelectric layer 103. The diaphragm layer 106 and the piezoelectric layer 103 may be continuous film layers or patterned film layers.
Fig. 8 is a schematic longitudinal cross-sectional view of an ultrasound transducer provided in an embodiment of the present application, and optionally, the ultrasound transducer 10 includes: the piezoelectric actuator comprises a first electrode 101, a second electrode 102, a piezoelectric layer 103, a support layer 104, a third electrode 105 and a vibrating membrane layer 106, wherein the first electrode 101 and the third electrode 105 are two round flat plate electrodes which are opposite to each other, the first electrode 101 and the third electrode 105 are respectively arranged above and below the piezoelectric layer 103, the second electrode 102 is a circular ring flat plate electrode, the second electrode 102 is arranged between the piezoelectric layer 103 and the vibrating membrane layer 106, the support layer is arranged below the piezoelectric layer, the vibrating membrane layer 106 is arranged between the piezoelectric layer 103 and the support layer 104, the radius of an inner ring of the second electrode 102 is larger than that of the first electrode 101, the support layer 104 is provided with a cylindrical opening 1041, and the radius of the opening 1041 is equal to that of the inner ring of the second electrode 102.
The ultrasonic transducer that this application embodiment provided, first electrode and second electrode are fixed in the top and the below of piezoelectric layer respectively, and the horizontal distance of first electrode and second electrode is more than or equal to and predetermines the distance, because the horizontal distance of two electrodes is more than or equal to and predetermines the distance, under the unchangeable condition of electric charge amount, has reduced the electric capacity size, has increased voltage, has improved sensitivity.
Example II,
Based on the ultrasound transducer 10 described in the first embodiment, the present application provides an information acquisition element including the ultrasound transducer 10 as described in the first embodiment.
Optionally, in an embodiment of the present application, the information collecting element is a microphone, an ultrasonic radar, an ultrasonic imaging device, an ultrasonic fingerprint collecting device or a proximity sensor 100.
Here, the information acquisition element is described by taking two specific examples, which are, of course, only exemplary and not meant to limit the present application:
in a first example, the information collecting element is an ultrasonic fingerprint collecting device, as shown in fig. 9, fig. 9 is a schematic diagram of fingerprint collection provided in the embodiment of the present application, the ultrasonic fingerprint collecting device may be installed on an electronic device, for example, the electronic device may be an intelligent terminal with a fingerprint collecting function, a fingerprint detection area is in a specific area of a panel of the electronic device, taking a fingerprint unlocking function of a smartphone as an example, when the smartphone needs to be unlocked, a user only needs to press a finger on the fingerprint detection area, so as to complete fingerprint identification. The fingerprint detection area can be arranged in a specific area of the display screen, and can also be arranged in a special fingerprint detection area (such as a Home key).
Fig. 10 is a schematic longitudinal sectional view of an ultrasonic fingerprint acquisition according to an embodiment of the present application. The ultrasonic fingerprint acquisition device comprises an ultrasonic propagation medium 1001 and an ultrasonic transducer array 1002, wherein the ultrasonic transducer array 1002 consists of at least two ultrasonic transducers 10 as described in the first embodiment. The ultrasound propagation medium 1001 is capable of conveying ultrasound signals generated by the ultrasound transducer array 1002 to the finger via the panel of the electronic device. The ultrasonic wave is reflected at the interface of a panel, air or glass and skin, and the intensity of the reflected ultrasonic signal is different due to the large difference of acoustic impedance of the air and the skin, so that the fingerprint can be imaged.
In a second example, the information acquisition element is a proximity sensor 110, as shown in fig. 11, fig. 11 is a schematic longitudinal cross-sectional view of a proximity sensor provided in an embodiment of the present application, and the proximity sensor 110 includes an ultrasonic transducer 10, a substrate 1101, an integrated circuit 1102, and a cover 1103. Wherein, the ultrasonic transducer 10 is the ultrasonic transducer 10 described in the first embodiment, in this example, the supporting layer 104 of the ultrasonic transducer 10 is provided with a cylindrical opening 1041, the opening 1041 is a circular through hole, the substrate 1101 is provided with an acoustic hole 11011, the acoustic hole 11011 may be located below the circular through hole of the supporting layer 104, and central axes of the acoustic hole 11011 and the circular through hole are aligned in coincidence.
The ultrasonic performance of the sensor can be enhanced by designing the diameter and length dimensions of the circular through hole and the acoustic hole 11011 such that the circular through hole and the acoustic hole 11011 form an acoustic resonant cavity. For a given operating frequency f, the resonance condition may be satisfied when the effective length L of the acoustic resonator is equal to an odd multiple of the 1/4 wavelength, i.e., L ═ n λ/4, where n ═ 1,3,5 …, λ ═ c/f, λ denotes wavelength, c is the speed of sound, and f is the frequency.
After the sound wave enters the proximity sensor 110 through the sound hole 11011, air in the circular through hole is caused to vibrate, and then the piezoelectric layer 103 of the ultrasonic transducer 10 is caused to vibrate, and the electrodes on both sides of the piezoelectric layer 103 generate a voltage difference and transmit an electrical signal to the integrated circuit 1102.
The information acquisition component that this application embodiment provided, first electrode and second electrode are fixed in the top and the below of piezoelectric layer respectively, and the horizontal distance of first electrode and second electrode is more than or equal to and predetermines the distance, because the horizontal distance of two electrodes is more than or equal to and predetermines the distance, under the unchangeable condition of electric charge amount, has reduced the electric capacity size, has increased voltage, has improved sensitivity.
Example III,
Based on the ultrasonic transducer 10 described in the first embodiment, an electronic device 120 is provided in the embodiment of the present application, as shown in fig. 12, and fig. 12 is a structural diagram of an electronic device provided in the embodiment of the present application, where the electronic device 120 includes the ultrasonic transducer 10 described in the first embodiment.
Optionally, in an embodiment of the present application, the electronic device 120 includes an ultrasound transducer array, which is an array composed of at least two ultrasound transducers 10 as described in embodiment one.
Optionally, as shown in fig. 11, the electronic device 120 comprises a processor 1201, a memory 1202, and a bus 1203, the processor 1201, the memory 1202, and the ultrasound transducer 10 communicating with each other through the bus 1203.
The processor 1201 may be the central processing unit 1201CPU or a Specific Integrated circuit 1102asic (application Specific Integrated circuit) or one or more Integrated circuits 1102 configured to implement an embodiment of the present invention. The one or more processors 1201 included in the electronic device 120 may be the same type of processor 1201, such as one or more CPUs; or may be a different type of processor 1201 such as one or more CPUs and one or more ASICs.
The memory 1202 stores programs. Memory 1202 may include high-speed RAM memory 1202, and may also include non-volatile memory 1202 (e.g., at least one disk memory 1202).
The electronic equipment that this application embodiment provided, first electrode and second electrode are fixed in the top and the below of piezoelectric layer respectively, and the horizontal distance of first electrode and second electrode is more than or equal to and predetermines the distance, because the horizontal distance of two electrodes is more than or equal to and predetermines the distance, under the unchangeable condition of electric charge amount, has reduced the electric capacity size, has increased voltage, has improved sensitivity.
The electronic device of the embodiments of the present application exists in various forms, including but not limited to:
(1) mobile communication devices, which are characterized by mobile communication capabilities and are primarily targeted at providing voice and data communications. Such terminals include smart phones (e.g., iphones), multimedia phones, functional phones, and low-end phones, among others.
(2) The ultra-mobile personal computer equipment belongs to the category of personal computers, has calculation and processing functions and generally has the characteristic of mobile internet access. Such terminals include PDA, MID, and UMPC devices, such as ipads.
(3) Portable entertainment devices such devices may display and play multimedia content. Such devices include audio and video players (e.g., ipods), handheld game consoles, electronic books, as well as smart toys and portable car navigation devices.
(4) The server is similar to a general computer architecture, but has higher requirements on processing capability, stability, reliability, safety, expandability, manageability and the like because of the need of providing highly reliable services.
(5) And other electronic devices with data interaction functions.
Thus, particular embodiments of the present subject matter have been described. Other embodiments are within the scope of the present application. In some cases, the actions recited in the present application may be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may be advantageous.
In the 90 s of the 20 th century, improvements in a technology could clearly distinguish between improvements in hardware (e.g., improvements in circuit structures such as diodes, transistors, switches, etc.) and improvements in software (improvements in process flow). However, as technology advances, many of today's process flow improvements have been seen as direct improvements in hardware circuit architecture. Designers almost always obtain the corresponding hardware circuit structure by programming an improved method flow into the hardware circuit. Thus, it cannot be said that an improvement in the process flow cannot be realized by hardware physical modules. For example, a Programmable Logic Device (PLD), such as a Field Programmable Gate Array (FPGA), is an integrated circuit whose Logic functions are determined by programming the Device by a user. A digital system is "integrated" on a PLD by the designer's own programming without requiring the chip manufacturer to design and fabricate application-specific integrated circuit chips. Furthermore, nowadays, instead of manually making an Integrated Circuit chip, such Programming is often implemented by "logic compiler" software, which is similar to a software compiler used in program development and writing, but the original code before compiling is also written by a specific Programming Language, which is called Hardware Description Language (HDL), and HDL is not only one but many, such as abel (advanced Boolean Expression Language), ahdl (alternate Hardware Description Language), traffic, pl (core universal Programming Language), HDCal (jhdware Description Language), lang, Lola, HDL, laspam, hardward Description Language (vhr Description Language), vhal (Hardware Description Language), and vhigh-Language, which are currently used in most common. It will also be apparent to those skilled in the art that hardware circuitry that implements the logical method flows can be readily obtained by merely slightly programming the method flows into an integrated circuit using the hardware description languages described above.
The controller may be implemented in any suitable manner, for example, the controller may take the form of, for example, a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro) processor, logic gates, switches, an Application Specific Integrated Circuit (ASIC), a programmable logic controller, and an embedded microcontroller, examples of which include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicone Labs C8051F320, the memory controller may also be implemented as part of the control logic of the memory. Those skilled in the art will also appreciate that, in addition to implementing the controller as pure computer readable program code, the same functionality can be implemented by logically programming method steps such that the controller is in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Such a controller may thus be considered a hardware component, and the means included therein for performing the various functions may also be considered as a structure within the hardware component. Or even means for performing the functions may be conceived to be both a software module implementing the method and a structure within a hardware component.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.
The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (15)
1. An ultrasonic transducer, comprising: a first electrode, a second electrode, a piezoelectric layer, and a support layer;
the piezoelectric layer is made of a piezoelectric material; the first electrode and the second electrode are respectively fixed above and below the piezoelectric layer; the horizontal distance between the first electrode and the second electrode is greater than or equal to a preset distance, and the preset distance is greater than 0;
the supporting layer is fixed below the piezoelectric layer and provided with an upward opening which is a blind hole or a through hole, and the piezoelectric layer covers the opening;
the second electrode is an annular flat plate electrode; the projection of the first electrode on the second electrode is located within the ring shape of the second electrode.
2. The ultrasonic transducer of claim 1,
the piezoelectric layer is in contact with the edge of the opening on the upper surface of the support layer, and the second electrode is arranged between the piezoelectric layer and the support layer.
3. The ultrasonic transducer of claim 2, wherein an upper surface of the second electrode is in contact with a lower surface of the piezoelectric layer, and wherein the lower surface of the second electrode is in contact with an upper surface around the opening of the support layer.
4. The ultrasonic transducer of claim 1, wherein the first and second electrodes are flat plate electrodes.
5. The ultrasonic transducer according to claim 4, wherein the opening of the support layer is a cylindrical hollow region, the second electrode is circular ring-shaped, and the ratio of the radius of the inner ring of the second electrode to the radius of the opening is within a preset range.
6. The ultrasonic transducer of claim 5, wherein the inner ring radius of the second electrode is equal to the radius of the aperture.
7. The ultrasonic transducer of claim 1, further comprising a third electrode on the same side of the piezoelectric layer as the second electrode, the third electrode facing the first electrode.
8. The ultrasonic transducer of claim 7, wherein the third electrode is separated from the second electrode.
9. The ultrasonic transducer of claim 8, wherein the second electrode is disposed around the third electrode, the third electrode being disposed at the aperture of the support layer.
10. The ultrasonic transducer according to any one of claims 1 to 9 further comprising a membrane layer secured between said support layer and said piezoelectric layer.
11. The ultrasonic transducer of claim 10, wherein the diaphragm layer is made of an insulating material.
12. An information acquisition element comprising an ultrasound transducer according to any of claims 1 to 11.
13. The information-gathering component of claim 12, wherein the information-gathering component is a microphone, an ultrasonic radar, an ultrasonic imaging device, an ultrasonic fingerprint-gathering device, or a proximity sensor.
14. An electronic device comprising the ultrasound transducer of any of claims 1-11.
15. An electronic device according to claim 14, characterized in that the electronic device comprises an ultrasound transducer array, which is an array of at least two ultrasound transducers according to any of claims 1-11.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/CN2019/119922 WO2021097749A1 (en) | 2019-11-21 | 2019-11-21 | Ultrasonic transducer, information acquisition element, and electronic device |
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| CN113165017A CN113165017A (en) | 2021-07-23 |
| CN113165017B true CN113165017B (en) | 2022-06-10 |
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| CN113617622B (en) * | 2021-08-12 | 2022-07-12 | 深圳市青鼎装备有限公司 | Ultrasonic knife handle based on solid piezoelectric ceramic piece |
| CN116320916B (en) * | 2023-01-31 | 2023-11-24 | 广州市声讯电子科技股份有限公司 | Transduction driver |
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| CN102596431B (en) * | 2009-11-09 | 2016-01-20 | 皇家飞利浦电子股份有限公司 | With the high-intensity focusing ultrasonic transducer of nonmagnetic conductive passage |
| CN103456795A (en) * | 2013-09-02 | 2013-12-18 | 合肥京东方光电科技有限公司 | Thin film transistor, manufacturing method thereof, array substrate and display device |
| CN103675348B (en) * | 2013-12-09 | 2015-10-21 | 南京信息工程大学 | Z axis capacitance type micromechanical accelerometer |
| CN104461208B (en) * | 2015-01-05 | 2017-12-05 | 京东方科技集团股份有限公司 | A kind of capacitance type in-cell touch panel and display device |
| JP6724502B2 (en) * | 2016-04-06 | 2020-07-15 | セイコーエプソン株式会社 | Ultrasonic device |
| US10656255B2 (en) * | 2016-05-04 | 2020-05-19 | Invensense, Inc. | Piezoelectric micromachined ultrasonic transducer (PMUT) |
| CN106412780B (en) * | 2016-09-05 | 2020-06-05 | 南昌欧菲生物识别技术有限公司 | Ultrasonic probe and method for manufacturing same |
| CN109301061A (en) * | 2018-09-28 | 2019-02-01 | 天津大学 | Flexible miniature piezoelectric ultrasonic transducer, array and forming method thereof |
| CN109561876A (en) * | 2018-10-24 | 2019-04-02 | 深圳市汇顶科技股份有限公司 | Ultrasonic transducer and its manufacturing method |
| CN209531368U (en) * | 2018-11-20 | 2019-10-25 | 深圳市汇顶科技股份有限公司 | Supersonic changer element and electronic device |
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| WO2021097749A1 (en) | 2021-05-27 |
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