CN109688494B - Acoustic sensor and method for manufacturing the same - Google Patents
Acoustic sensor and method for manufacturing the same Download PDFInfo
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- CN109688494B CN109688494B CN201910010412.6A CN201910010412A CN109688494B CN 109688494 B CN109688494 B CN 109688494B CN 201910010412 A CN201910010412 A CN 201910010412A CN 109688494 B CN109688494 B CN 109688494B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/08—Mouthpieces; Microphones; Attachments therefor
- H04R1/083—Special constructions of mouthpieces
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R31/00—Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2231/00—Details of apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor covered by H04R31/00, not provided for in its subgroups
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- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Manufacturing & Machinery (AREA)
- Testing Or Calibration Of Command Recording Devices (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The invention provides an acoustic sensor and a manufacturing method thereof, relating to the field of acoustic sensors, wherein the acoustic sensor comprises: a substrate; the sound wave sensing assembly is electrically connected with the substrate, is a porous structure body and comprises a foam metal substrate and an electric conduction heat conduction film arranged on the foam metal substrate, wherein when a power supply applies constant voltage to the sound wave sensing assembly through the substrate, the sound wave sensing assembly generates an electric signal according to the received sound wave. Through exerting constant voltage for sound wave sensing assembly, when it receives the sound wave excitation, the electrically conductive heat conduction membrane on the foam metal substrate can lead to temperature variation because the sound wave arouses the air density change, and then arouses electrically conductive heat conduction membrane to produce extra electric potential, can realize the detection to the sound wave through detecting this extra electric potential, and this acoustic sensor's simple structure has reduced the risk that acoustic sensor breaks down, has guaranteed acoustic sensor's reliability.
Description
Technical Field
The invention relates to the field of acoustic sensors, in particular to an acoustic sensor and a manufacturing method thereof.
Background
With the development of socioeconomic and technical features, particularly with the popularization of various portable electronic devices, acoustic sensors capable of sensing sound are gaining wide attention.
Sound is the particle vibration propagation of an air medium, and the sound field characteristics are generally described by three physical quantities, namely sound pressure, sound particle vibration velocity and sound impedance. An acoustic sensor, commonly referred to as a microphone, is a device that converts an acoustic signal into an electrical signal. The traditional microphone is divided into a moving coil type, a capacitance type, an electret type, an aluminum strip type and the like according to the working principle. Taking a moving-coil microphone as an example, when a diaphragm of the microphone is impacted by a sound signal, the moving-coil microphone drives a coil to move in a magnetic field, thereby generating a voltage output.
However, conventional acoustic sensors are generally complex in construction and are at a high risk of failure because failure of any structural component may cause the entire acoustic sensor to fail.
Disclosure of Invention
The present invention is directed to provide an acoustic sensor and a method for manufacturing the same, which solve the problem of high risk of failure of the acoustic sensor.
In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solutions:
in a first aspect, an embodiment of the present invention provides an acoustic sensor, including:
a substrate;
the acoustic wave sensing assembly is electrically connected with the substrate, the acoustic wave sensing assembly is a porous structure body, the porous structure body comprises a foam metal substrate and an electric conduction heat conduction film arranged on the foam metal substrate,
when the power supply applies a constant voltage to the acoustic wave sensing assembly through the substrate, the acoustic wave sensing assembly generates an electric signal according to the received acoustic wave.
Optionally, the acoustic wave sensing assembly is electrically connected to the substrate through a conductive silver paste.
Optionally, the acoustic sensor further comprises:
and the signal acquisition assembly is electrically connected with the sound wave sensing assembly and is used for acquiring an electric signal generated by the sound wave sensing assembly.
Optionally, the signal acquisition assembly is a wheatstone bridge circuit.
Optionally, the electrically and thermally conductive film is a graphene film.
Optionally, the acoustic wave sensing assembly is in the shape of a sheet.
Optionally, the porosity of the porous structure is from 10% to 90%.
Optionally, the acoustic sensor further comprises:
and the dustproof assembly is covered around the acoustic wave sensing assembly and is used for preventing external pollutants from entering the acoustic wave sensing assembly.
In a second aspect, an embodiment of the present invention further provides a method for manufacturing an acoustic sensor, including:
arranging a substrate;
forming an acoustic wave sensing assembly electrically connected with the substrate, wherein the acoustic wave sensing assembly is a porous structure body which comprises a foam metal substrate and an electric conduction heat conduction film arranged on the foam metal substrate;
when the power supply applies a constant voltage to the acoustic wave sensing assembly through the substrate, the acoustic wave sensing assembly generates an electric signal according to the received acoustic wave.
Optionally, the electrically and thermally conductive film is a graphene film;
the acoustic wave sensing assembly formed in electrical connection with a substrate includes:
arranging a foam metal substrate;
depositing a graphene film on a foam metal substrate to obtain an acoustic wave sensing assembly;
the acoustic wave sensing assembly is electrically connected with the substrate.
The beneficial effects of the invention include:
the acoustic sensor provided by the embodiment of the invention comprises: a substrate; the sound wave sensing assembly is electrically connected with the substrate, is a porous structure body and comprises a foam metal substrate and an electric conduction heat conduction film arranged on the foam metal substrate, wherein when a power supply applies constant voltage to the sound wave sensing assembly through the substrate, the sound wave sensing assembly generates an electric signal according to the received sound wave. Through exerting constant voltage for sound wave sensing assembly, when it receives the sound wave excitation, the electrically conductive heat conduction membrane on the foam metal substrate can lead to temperature variation because the sound wave arouses the air density change, and then arouses the inside electron motion state of electrically conductive heat conduction membrane to change and produce extra electric potential, can realize the detection to the sound wave through detecting this extra electric potential, this acoustic sensor's simple structure has reduced the risk that acoustic sensor breaks down, has guaranteed acoustic sensor's reliability.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic structural diagram of an acoustic sensor according to an embodiment of the present invention;
FIG. 2 is a photograph of an acoustic wave sensing assembly according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of an acoustic sensor according to another embodiment of the present invention;
FIG. 4 is an equivalent circuit diagram of the acoustic sensor of FIG. 3;
FIG. 5 is a sectional view taken along line A-A of FIG. 3;
FIG. 6 is a graph illustrating the response of an acoustic sensor according to an embodiment of the present invention;
fig. 7 is a schematic structural diagram of an acoustic sensor according to another embodiment of the present invention;
fig. 8 is a schematic flow chart illustrating a method for manufacturing an acoustic sensor according to an embodiment of the present invention;
fig. 9 is a schematic flow chart illustrating a method for manufacturing an acoustic sensor according to another embodiment of the present invention.
Icon: 100-a substrate; 200-an acoustic wave sensing assembly; 300-voltage electrode contacts; 400-measuring electrode contact; 500-a signal acquisition component; 600-dust prevention assembly.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention.
Fig. 1 is a schematic structural diagram of an acoustic sensor according to an embodiment of the present invention, and as shown in fig. 1, the acoustic sensor includes: a substrate 100; the acoustic wave sensing assembly 200 is electrically connected to the substrate 100, and the acoustic wave sensing assembly 200 is a porous structure including a metal foam substrate and an electrically conductive and thermally conductive film disposed on the metal foam substrate.
When a power source applies a constant voltage to the acoustic wave sensing device 200 through the substrate 100, the acoustic wave sensing device 200 can generate an electrical signal according to the received acoustic wave.
As shown in fig. 1, the substrate 100 may be electrically connected with the acoustic wave sensing assembly 200 via two voltage electrode contacts 300, so that a constant voltage may be applied to the acoustic wave sensing assembly 200 via the voltage electrode contacts 300. Although the acoustic wave sensing assembly 200 is shown in fig. 1 as being disposed in the middle region of the substrate 100, it should be understood that the invention is not limited thereto.
Further, in the region where the substrate 100 is in contact with the acoustic wave sensing component 200, the substrate 100 is insulated from the acoustic wave sensing component 200 in other contact regions, except for the region where the voltage electrode contact 300 is provided to enable electrical connection of the substrate 100 and the acoustic wave sensing component 200.
Referring to fig. 2, the acoustic wave sensing assembly 200 is a porous structure in which a large number of air gaps exist, and includes a metal foam substrate and an electrically conductive and thermally conductive film disposed on the metal foam substrate.
It should be noted that, although the acoustic wave sensing assembly 200 shown in fig. 2 is in a cubic structure, it should be understood that the photograph of the acoustic wave sensing assembly 200 provided in fig. 2 is merely illustrative of the appearance of the porous structure, and the present invention is not limited thereto, and for example, the acoustic wave sensing assembly 200 may be prepared in various shapes such as a cylinder, a sheet, a sphere, and the like.
When a constant voltage is applied to the acoustic wave sensing assembly 200 via the substrate 100, since the porous structure of the acoustic wave sensing assembly 200 is composed of the foamed metal base and the electrically and thermally conductive film, a voltage is applied to the electrically and thermally conductive film. The electric conduction and heat conduction film has certain resistance, so the electric conduction and heat conduction film can generate heat, when the applied voltage is constant, the balance state of the heat generated by the electric conduction and heat conduction film and the ambient environment can be finally realized, and the temperature of the electric conduction and heat conduction film is relatively constant in the balance state. At this time, when external acoustic wave excitation exists, density change of air in the gaps of the porous structure body is caused, so that heat balance between the conductive heat-conducting film and the surrounding environment is broken, and temperature change of the conductive heat-conducting film is caused. On the other hand, the airflow caused by the external acoustic wave excitation can also cause the heat on the surface of the conductive heat-conducting film to be lost, thereby causing the temperature change of the conductive heat-conducting film. The temperature change of the conductive heat-conducting film causes the motion state of electrons in the conductive heat-conducting film to change, so that additional electric potential is generated, and the detection of sound waves can be realized by detecting the additional electric potential.
The substrate 100 may be a PCB (Printed Circuit Board), or may be a substrate that can be electrically connected to the acoustic wave sensing assembly 200 through an electrode contact portion, and can apply a constant voltage to the acoustic wave sensing assembly 200, which is not limited in the embodiment of the present invention.
For example, in the case that the substrate 100 is a PCB, the substrate 100 is provided with a conductive lead, and the conductive lead on the substrate 100 is electrically connected to the acoustic wave sensing assembly 200 through the voltage electrode contact 300, and at this time, the power supply may apply a constant voltage to the acoustic wave sensing assembly 200 through the conductive lead on the substrate 100.
Also, the embodiment of the present invention has no limitation on the shape of the substrate 100. For example, the substrate 100 may have a ring shape as shown in fig. 1, and may have a bar shape or other shapes.
Since the foam metal substrate of the acoustic wave sensing assembly 200 can be self-supporting, in practical applications, the substrate 100 may provide a support for the acoustic wave sensing assembly 200, and the substrate 100 may not provide a support for the acoustic wave sensing assembly 200.
The substrate 100 may be electrically connected to the acoustic wave sensing device 200 through two voltage electrode contacts 300 disposed at the left and right ends of the acoustic wave sensing device 200 as shown in fig. 1, or may be electrically connected to the acoustic wave sensing device 200 through another number of voltage electrode contacts 300 disposed at another position between the substrate 100 and the acoustic wave sensing device 200, which is not limited in this disclosure.
Alternatively, in order to achieve good electrical connection between the substrate 100 and the acoustic wave sensing assembly 200, the voltage electrode contact 300 may be formed of conductive silver paste. The conductive silver paste is a viscous paste of a mechanical mixture consisting of high-purity metal silver particles, a binder, a solvent and an auxiliary agent. The conductive silver paste is liquid in the initial state, and in this case, good electrical contact between the three-dimensional porous structure and the electrode on the substrate 100 can be ensured, and contact resistance can be reduced to a large extent. After the conductive silver paste is cured, the substrate 100 and the acoustic wave sensing assembly 200 can be fixed together.
The foam metal substrate used to form the acoustic wave sensing assembly 200 refers to a specialty metal material containing foam pores. Through the unique structural characteristics of the foam metal, the foam metal has a series of good advantages of small density, good heat insulation performance, good sound insulation performance, capability of absorbing sound waves and the like. Porosity is the ratio of the volume of all pores in the porous body to the total volume of the porous body, and can be measured as the size of the void space of the porous body. The porosity of the foam metal can reach a higher value, and the foam metal has certain strength and rigidity, and the pore diameter can reach a millimeter level.
Because the foamed metal has high air permeability and is almost communicated with pores, the specific surface area of pores is large, and the weight of the material is small.
Since the foam metal is a two-phase composite material consisting of a metal matrix skeleton continuous phase and a gas pore dispersed phase or continuous phase, the properties of the foam metal depend on the metal matrix, the porosity and the gas pore structure used and are influenced by the preparation process. In general, the mechanical properties of the metal foam decrease with increasing porosity, and the electrical conductivity and thermal conductivity decrease exponentially. When the foam metal bears pressure, the stress area is increased due to air hole collapse and the material strain hardening effect, so that the foam metal has excellent impact energy absorption characteristics.
In the embodiment of the invention, the conductive and heat-conducting film is arranged on the foam metal substrate, and the thickness of the conductive and heat-conducting film is usually very thin, so that the influence on the porosity and the mechanical property of the foam metal substrate is very small. Thus, in embodiments of the present invention, the porosity of the metal foam substrate is approximately the same as the porosity of the porous structure. Preferably, in the present embodiment, the porosity of the porous structure may be 10% to 90%. Because, when the porosity is less than 10%, the air gap in the porous structure is small, the response to the excitation of the external acoustic wave is very small, thereby affecting the detection of the external acoustic wave. When the porosity is greater than 90%, the mechanical strength of the metal foam substrate may be reduced, affecting the self-support of the acoustic wave sensing assembly 200.
The foamed metal is prepared by a powder metallurgy method and an electroplating method, wherein the foaming agent is added into the melt metal to prepare the foamed metal; the latter is replicated as a metal foam on a polyurethane foam backbone by an electrodeposition process. The material of the foam metal can be aluminum, nickel, copper and alloy thereof.
The electrically and thermally conductive film on the metal foam substrate may be any film having electrically and thermally conductive properties. For example, the electrically and thermally conductive film may be a graphene film.
Graphene is a hexagonal honeycomb lattice two-dimensional carbon nanomaterial composed of carbon atoms. Graphene has excellent electrical and thermal properties. The carrier mobility of graphene at room temperature is about 15000cm2V · s, this value is more than 10 times that of the silicon material. At low temperature, the carrier mobility of graphene can even reach 250000cm2V · s. Unlike many materials, the electron mobility of graphene is less affected by temperature changes, and the electron mobility of single-layer graphene is 15000cm at any temperature between 50K and 500K2and/(V · s) or so. Graphene has very good thermal conductivity. The thermal conductivity coefficient of pure defect-free single-layer graphene is as high as 5300W/mK, which is higher than that of single-wall carbon nanotubes (3500W/mK) and multi-wall carbon nanotubes (3000W/mK). When the graphene is used as a carrier, the thermal conductivity coefficient can also reach 600W/mK.
Conventional production methods of graphene may include a mechanical exfoliation method, a redox method, an epitaxial growth method, a chemical vapor deposition method. The chemical vapor deposition method is a method for preparing a graphene film by vapor deposition by using carbon-containing organic gas as a raw material. In the embodiment of the present invention, for example, a chemical vapor deposition method may be used to deposit a graphene film on a metal foam substrate.
Alternatively, the electrically and thermally conductive film may also be a film-like structure formed of carbon nanotubes. For example, the acoustic wave sensing assembly 200 can be formed by depositing a large number of carbon nanotubes on a metal foam substrate.
In summary, the acoustic sensor provided in the embodiments of the present invention includes: a substrate 100; the acoustic wave sensing assembly 200 is electrically connected to the substrate 100, and the acoustic wave sensing assembly 200 is a porous structure body including a metal foam substrate and an electrically conductive and thermally conductive film disposed on the metal foam substrate, wherein when a power source applies a constant voltage to the acoustic wave sensing assembly 200 through the substrate 100, the acoustic wave sensing assembly 200 generates an electrical signal according to the received acoustic wave. Through exerting constant voltage for sound wave sensing assembly 200, when it receives the sound wave excitation, the electrically conductive heat conduction membrane on the foam metal substrate can lead to temperature variation because the sound wave arouses the air density change, and then arouses the inside electron motion state of electrically conductive heat conduction membrane to change and produce extra electric potential, can realize the detection to the sound wave through detecting this extra electric potential, this acoustic sensor's simple structure has reduced the risk that acoustic sensor breaks down, has guaranteed acoustic sensor's reliability.
Fig. 3 is a schematic structural diagram of an acoustic sensor according to another embodiment of the present invention, and as shown in fig. 3, compared with the acoustic sensor provided in fig. 1, the acoustic sensor further includes a signal collecting assembly 500, where the signal collecting assembly 500 is electrically connected to the acoustic wave sensing assembly 200 and is used for collecting an electrical signal generated by the acoustic wave sensing assembly 200.
For example, the signal acquisition assembly 500 may be electrically connected to the acoustic wave sensing assembly 200 through the measurement electrode contact 400. The measuring electrode contact 400 is similar to the voltage electrode contact 300, and the measuring electrode contact 400 may be formed using conductive silver paste. The measurement electrode contact 400 is used to electrically connect the signal acquisition assembly 500 and the acoustic wave sensing assembly 200, so there is no direct electrical connection between the measurement electrode contact 400 and the substrate 100.
Although the measurement electrode contact 400 is shown in fig. 3 to be located at the upper and lower ends of the acoustic wave sensing assembly 200, the invention is not limited thereto, and the measurement electrode contact 400 may be located at other positions of the acoustic wave sensing assembly 200 as long as there is no direct electrical connection between the measurement electrode contact 400 and the substrate 100.
The signal acquisition assembly 500 can be a wheatstone bridge circuit. An equivalent circuit diagram for acquiring the output signal of the acoustic wave sensing assembly 200 using a wheatstone bridge circuit is shown in fig. 4. In FIG. 4, S denotes the acoustic wave sensing assembly 200, and since the resistance of the metal foam substrate of the acoustic wave sensing assembly 200 is typically very small, the resistance of the acoustic wave sensing assembly 200 is mainly composed of the resistance of the electrically conductive and thermally conductive film, VBFor bias voltage, the three resistors R1, R2 and R3 are balanced matching resistors, the resistance values of the balanced matching resistors are the same as that of the conductive heat-conducting film, and at the moment, the resistance value of the conductive heat-conducting film changes to cause the bridge to be unbalanced, so that an output voltage signal is obtained. The voltage signal passes through a filter (formed by a capacitor C)FAnd a resistance RFComposition) the filtered output is VSAnd then the sound collecting card collects VSThen obtaining the sound signal.
Specifically, the resistance of the conductive heat-conducting film in the equilibrium state is set to be R, the resistance after being excited by sound is set to be R + Δ R, R1 ═ R2 ═ R3 ═ R, and therefore, the output voltage of the bridge arm of the wheatstone bridge is set to be:
in this embodiment, the acoustic wave sensing assembly 200 can be in the shape of a thin plate. As shown in fig. 5, the dimension of the acoustic wave sensing device 200 in the direction perpendicular to the plane of the substrate 100 is much smaller than the dimension of the acoustic wave sensing device 200 in the direction parallel to the plane of the substrate 100. In this case, the sound waves incident on the sound wave sensing assembly 200 along different directions generate voltage outputs of different magnitudes, when the sound waves are incident perpendicular to the plane of the substrate 100, the heat loss on the surface of the conductive heat-conducting film is the largest, and the output signal is the largest, and when the sound waves are incident parallel to the plane of the substrate 100, the output signal is the smallest.
As shown in FIG. 6, the solid line represents the measured response voltage versus frequency when the sound incidence direction is parallel to the plane of the substrate 100 (i.e., the incidence angle is 90), and the dotted line represents the sound incidence direction perpendicular to the plane of the substrate 100 (i.e., the incidence angle is 90 deg.)The measured response voltage in fig. 6 is an effective value (in V) of the measured voltage generated by the acoustic wave sensor in response to the incident sound, which is a function of the measured response voltage at the incident angle of 0 ° with respect to the frequencyrms) The frequency is the frequency of the incident sound. Thus, the acoustic wave sensor realizes directivity. The directivity of the acoustic wave sensor means that the acoustic wave sensor picks up sound from different directions. In practical application, it is important to determine the directivity of the acoustic wave sensor used, and by selecting and appropriately setting the acoustic wave sensor having appropriate directivity, it is possible to reduce the feedback of sound and improve the sound pickup effect.
To sum up, further set up signal acquisition assembly 500 in acoustic sensor, through exerting constant voltage for sound wave sensing assembly 200, when it receives the acoustic wave excitation, the electrically conductive heat conduction membrane on the foam metal substrate can lead to temperature variation because the sound wave arouses the air density change, and then arouse that the inside electron motion state of electrically conductive heat conduction membrane changes and produces extra electric potential, detect this extra electric potential through signal acquisition assembly 500 and can realize the detection to the sound wave, this acoustic sensor's simple structure, the risk that acoustic sensor breaks down has been reduced, acoustic sensor's reliability has been guaranteed.
Fig. 7 is a schematic structural diagram of an acoustic sensor according to another embodiment of the present invention, and as shown in fig. 7, compared with the acoustic sensor provided in fig. 1, the acoustic sensor further includes a dust-proof component 600 covering the acoustic sensing component 200, where the dust-proof component 600 is used to prevent external contaminants from entering the acoustic sensing component 200.
The acoustic wave sensing assembly 200 in the present embodiment is a porous structure, and in use, external contaminants (e.g., dust) may enter the voids of the porous structure, thereby affecting the performance of the acoustic sensor. Therefore, the dust-proof assembly 600 can be covered around the acoustic wave sensing assembly 200 to prevent external contaminants from entering the acoustic wave sensing assembly 200. The dust-proof assembly 600 may be a grid structure allowing sound waves to enter, and the material thereof may be metal or plastic, etc., which is not limited by the present invention.
Although it is illustrated in fig. 7 that the substrate 100 and the acoustic wave sensing assembly 200 are disposed together inside the dust prevention assembly 600, the present invention is not limited thereto, and in practical applications, other components than the acoustic wave sensing assembly 200 may be disposed inside or outside the dust prevention assembly 600.
In summary, the dust-proof assembly 600 is covered around the acoustic wave sensing assembly 200, so that the risk of failure of the acoustic sensor is further reduced, and the reliability of the acoustic sensor is ensured.
Fig. 8 is a schematic flowchart of a manufacturing method of an acoustic sensor according to an embodiment of the present invention, and as shown in fig. 8, the manufacturing method includes:
A substrate may be provided, which is itself insulated, the substrate being provided with electrically conductive leads for applying a voltage.
Wherein the acoustic wave sensing assembly is a porous structure body which comprises a foam metal substrate and an electric conduction and heat conduction film arranged on the foam metal substrate,
when the power supply applies a constant voltage to the acoustic wave sensing assembly through the substrate, the acoustic wave sensing assembly generates an electric signal according to the received acoustic wave.
The acoustic wave sensing device according to the foregoing embodiment of the present invention is first formed, and then electrically connected to the substrate through the conductive contact portion, such as conductive silver paste. Thus, a constant voltage can be applied to the acoustic wave sensing assembly through the substrate, and when the acoustic wave sensing assembly is excited by acoustic waves, the acoustic wave sensing assembly generates an electric signal according to the received acoustic waves.
In summary, the acoustic sensor provided in the foregoing embodiments of the present invention can be formed by the manufacturing method of the acoustic sensor provided in this embodiment. Through exerting constant voltage for sound wave sensing assembly, when it receives the sound wave excitation, the electrically conductive heat conduction membrane on the foam metal substrate can lead to temperature variation because the sound wave arouses the air density change, and then arouses the inside electron motion state of electrically conductive heat conduction membrane to change and produce extra electric potential, can realize the detection to the sound wave through detecting this extra electric potential, this acoustic sensor's simple structure has reduced the risk that acoustic sensor breaks down, has guaranteed acoustic sensor's reliability.
Fig. 9 is a schematic flow chart of a manufacturing method of an acoustic sensor according to another embodiment of the present invention, where the electrically and thermally conductive film may be a graphene film, as shown in fig. 9, and the manufacturing method includes:
This step 901 is similar to step 801 and will not be described herein again.
The metal foam substrate according to the foregoing embodiments of the present invention may be formed, and the material of the metal foam substrate may be, for example, aluminum, nickel, copper, or an alloy thereof.
And 903, depositing a graphene film on the foam metal substrate to obtain the acoustic wave sensing assembly.
The graphene film can be deposited on the foamed metal substrate through chemical vapor deposition, and a graphene film structure of a three-dimensional network can be grown by means of a three-dimensional porous skeleton of the foamed metal substrate, so that the acoustic wave sensing assembly formed by the foamed metal substrate and the graphene film is obtained.
The acoustic wave sensing assembly can be electrically connected to the substrate through conductive contacts, such as conductive silver paste. The power supply can apply a constant voltage to the acoustic wave sensing assembly through the substrate, and the acoustic wave sensing assembly generates an electrical signal according to the received acoustic wave when the acoustic wave sensing assembly is excited by the acoustic wave.
In summary, the acoustic sensor provided in the foregoing embodiments of the present invention can be formed by the manufacturing method of the acoustic sensor provided in this embodiment. By applying constant voltage to the acoustic wave sensing assembly, when the acoustic wave sensing assembly is excited by acoustic waves, the graphene film on the foam metal substrate can cause temperature change due to air density change caused by the acoustic waves, so that the electronic motion state in the graphene film is changed and extra electric potential is generated, the acoustic waves can be detected by detecting the extra electric potential, the acoustic sensor is simple in structure, the risk of failure of the acoustic sensor is reduced, and the reliability of the acoustic sensor is ensured.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. An acoustic sensor, comprising:
a substrate;
an acoustic wave sensing assembly electrically connected to the substrate, the acoustic wave sensing assembly being a porous structure having an air gap therein, the porous structure including a metal foam substrate and an electrically conductive and thermally conductive film disposed on the metal foam substrate,
when a power supply applies a constant voltage to the acoustic wave sensing assembly through the substrate, the voltage is applied to the conductive heat conduction film, when external acoustic wave excitation exists, density change of air in gaps of the porous structure is caused, the density change of the air causes temperature change of the conductive heat conduction film, the temperature change of the conductive heat conduction film causes a change of an electronic motion state inside the conductive heat conduction film, and extra electric potential is generated and used for detecting acoustic waves;
the shape of the acoustic wave sensing assembly includes at least one of: cube, cylinder, sheet, sphere.
2. The acoustic sensor of claim 1, wherein the acoustic wave sensing assembly is electrically connected to the substrate by a conductive silver paste.
3. The acoustic sensor of claim 1, further comprising:
the signal acquisition assembly is electrically connected with the sound wave sensing assembly and is used for acquiring an electric signal generated by the sound wave sensing assembly.
4. The acoustic sensor of claim 3, wherein the signal acquisition assembly is a Wheatstone bridge circuit.
5. The acoustic sensor of any of claims 1-4, wherein the electrically conductive, thermally conductive film is a graphene film.
6. The acoustic sensor of any one of claims 1 to 4, wherein the porosity of the porous structure is 10% to 90%.
7. The acoustic sensor of any one of claims 1-4, further comprising:
the dustproof assembly is covered on the periphery of the sound wave sensing assembly and used for preventing external pollutants from entering the sound wave sensing assembly.
8. A method of manufacturing an acoustic sensor, comprising:
arranging a substrate;
forming an acoustic wave sensing assembly electrically connected with the substrate, wherein the acoustic wave sensing assembly is a porous structure body, an air gap exists in the porous structure body, and the porous structure body comprises a foamed metal substrate and an electric conduction heat conduction film arranged on the foamed metal substrate;
when a constant voltage is applied to the acoustic wave sensing assembly through a power supply, the voltage is applied to the conductive heat conduction film, when external acoustic wave excitation exists, density change of air in gaps of the porous structure is caused, the density change of the air causes temperature change of the conductive heat conduction film, the temperature change of the conductive heat conduction film causes a change of an electronic motion state inside the conductive heat conduction film, and additional electric potential is generated and used for detecting acoustic waves;
the shape of the acoustic wave sensing assembly includes at least one of: cube, cylinder, sheet, sphere.
9. The manufacturing method according to claim 8, wherein the electrically and thermally conductive film is a graphene film;
the forming an acoustic wave sensing assembly in electrical connection with the substrate includes:
disposing the metal foam substrate;
depositing a graphene film on the foamed metal substrate to obtain the acoustic wave sensing assembly;
electrically connecting the acoustic wave sensing assembly with the substrate.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1989418A (en) * | 2004-07-27 | 2007-06-27 | 松下电工株式会社 | Acoustic wave sensor |
| CN106878913A (en) * | 2017-03-27 | 2017-06-20 | 清华大学 | Thermophone and preparation method based on weave mesh structure graphite alkene |
| CN108496375A (en) * | 2016-01-19 | 2018-09-04 | 索诺瓦公司 | Self-desiccation hearing aid and method for moisture to be transferred out of such hearing aid |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1764328B (en) * | 2004-10-18 | 2010-12-15 | 财团法人工业技术研究院 | Dynamic pressure sensing structure |
| CN101155437B (en) * | 2006-09-26 | 2012-12-05 | 财团法人工业技术研究院 | Back-placed microphone module group structure, microphone chip component and manufacturing method thereof |
| CN102307325B (en) * | 2011-07-21 | 2014-04-16 | 清华大学 | Thermophone device |
| CN103067838B (en) * | 2012-12-28 | 2015-10-28 | 缪建民 | A kind of preparation method of high sensitivity piezoelectric silicon microphone |
| CN103602964A (en) * | 2013-10-17 | 2014-02-26 | 常州二维碳素科技有限公司 | Method for preparing metal electrode on grapheme conductive film |
| KR102374090B1 (en) * | 2014-10-06 | 2022-03-14 | 더 로얄 인스티튜션 포 디 어드밴스먼트 오브 러닝/맥길 유니버시티 | Graphene oxide based acoustic transducer methods and devices |
| EP3166338B1 (en) * | 2015-11-05 | 2019-08-21 | Nokia Technologies Oy | An acoustic apparatus and associated methods |
| CN106937229A (en) * | 2015-12-31 | 2017-07-07 | 北京塞宾科技有限公司 | A kind of condenser type voice collection device and microphone |
| CN105671515B (en) * | 2016-03-24 | 2017-12-05 | 东南大学 | The simple method for preparing of monovalence golden nanometer particle/three-dimensional grapheme/nickel foam composite construction |
| WO2018035669A1 (en) * | 2016-08-22 | 2018-03-01 | Goertek. Inc | Capacitive mems microphone and electronic apparatus |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1989418A (en) * | 2004-07-27 | 2007-06-27 | 松下电工株式会社 | Acoustic wave sensor |
| CN108496375A (en) * | 2016-01-19 | 2018-09-04 | 索诺瓦公司 | Self-desiccation hearing aid and method for moisture to be transferred out of such hearing aid |
| CN106878913A (en) * | 2017-03-27 | 2017-06-20 | 清华大学 | Thermophone and preparation method based on weave mesh structure graphite alkene |
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