CN109494294B - Piezoelectric device and electronic apparatus - Google Patents
Piezoelectric device and electronic apparatus Download PDFInfo
- Publication number
- CN109494294B CN109494294B CN201811331276.2A CN201811331276A CN109494294B CN 109494294 B CN109494294 B CN 109494294B CN 201811331276 A CN201811331276 A CN 201811331276A CN 109494294 B CN109494294 B CN 109494294B
- Authority
- CN
- China
- Prior art keywords
- electrode
- circuit board
- metal plate
- layer
- piezoelectric
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910052751 metal Inorganic materials 0.000 claims abstract description 55
- 239000002184 metal Substances 0.000 claims abstract description 55
- 230000005284 excitation Effects 0.000 claims abstract description 10
- 238000004806 packaging method and process Methods 0.000 claims abstract description 3
- 239000010410 layer Substances 0.000 claims description 48
- 239000012790 adhesive layer Substances 0.000 claims description 21
- 238000003825 pressing Methods 0.000 claims description 3
- 239000003292 glue Substances 0.000 claims 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 9
- 238000005538 encapsulation Methods 0.000 description 7
- 239000011889 copper foil Substances 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- 239000004743 Polypropylene Substances 0.000 description 4
- 239000004820 Pressure-sensitive adhesive Substances 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229920001155 polypropylene Polymers 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- 239000000853 adhesive Substances 0.000 description 3
- 230000001070 adhesive effect Effects 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 230000000875 corresponding effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000003365 glass fiber Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- -1 polypropylene Polymers 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 239000010963 304 stainless steel Substances 0.000 description 1
- 229910000619 316 stainless steel Inorganic materials 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910000589 SAE 304 stainless steel Inorganic materials 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 239000002313 adhesive film Substances 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910000623 nickel–chromium alloy Inorganic materials 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000009662 stress testing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/80—Constructional details
- H10N30/88—Mounts; Supports; Enclosures; Casings
- H10N30/883—Additional insulation means preventing electrical, physical or chemical damage, e.g. protective coatings
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/01—Manufacture or treatment
- H10N30/02—Forming enclosures or casings
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Particle Formation And Scattering Control In Inkjet Printers (AREA)
- Electronic Switches (AREA)
- Telephone Set Structure (AREA)
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
The present invention provides a piezoelectric device and an electronic apparatus, the piezoelectric device including: the metal-based printed circuit board comprises a metal plate and a circuit board arranged on the metal plate, wherein the circuit board comprises a first top surface arranged away from the metal plate, a through hole is formed in the circuit board, and the through hole penetrates through the first top surface and faces to the surface of the metal plate; the piezoelectric element is used for generating vibration under the driving of an excitation voltage, is at least partially accommodated in the through hole and comprises a second top surface arranged to be away from the metal plate; and the packaging layer covers the second top surface and extends to the circuit board around the piezoelectric element, so that the area of the surface of the piezoelectric element, which is easily invaded by water vapor, can be reduced, and the reliability and the service life of the piezoelectric element, the piezoelectric device and the electronic equipment comprising the piezoelectric device can be improved.
Description
Technical Field
The present invention relates to a piezoelectric device and an electronic apparatus.
Background
Referring to fig. 1A-1B, fig. 1A is a schematic front view illustrating a conventional piezoelectric element 150 fixed on a circuit board 134, and fig. 1B is a schematic top view illustrating the conventional piezoelectric element 150 fixed on the circuit board 134. The circuit board 134 includes a first top surface 1341 and a first bottom surface 1342, wherein the first top surface 1341 is provided with the piezoelectric element 150. The piezoelectric element 150 includes a second top surface 151 and a second bottom surface 152, and the second bottom surface 152 is attached to the first top surface 1341.
After the piezoelectric element 150 is fixed on the circuit board 134, the package layer 110, such as a film, is used to package the piezoelectric element on the circuit board 134, and five surfaces of the piezoelectric element 150 except the second bottom surface 152 are isolated from the external environment by the package layer, which is easily penetrated by moisture.
Disclosure of Invention
An aspect of the present invention provides a piezoelectric device including:
the metal-based printed circuit board comprises a metal plate and a circuit board arranged on the metal plate, wherein the circuit board comprises a first top surface arranged away from the metal plate, and the circuit board forms a through hole which penetrates through the first top surface and faces to the surface of the metal plate;
the piezoelectric element is used for generating vibration under the driving of an excitation voltage, is at least partially accommodated in the through hole and comprises a second top surface arranged to be away from the metal plate; and
and the packaging layer covers the second top surface and extends to the circuit board around the piezoelectric element.
In another aspect, the present invention further provides an electronic device, including the piezoelectric device as described above, the electronic device including a power supply and a processor, wherein the power supply is configured to provide the excitation voltage for the piezoelectric device, and the processor is configured to analyze and process an output signal of the piezoelectric device.
In the piezoelectric device provided by the invention, at least part of the piezoelectric element is accommodated in the through hole formed in the metal-based printed circuit board, so that at least part of the side surfaces of the piezoelectric element, which are connected with the second top surface, are accommodated in the through hole, and the second bottom surface of the piezoelectric element, which is opposite to the second top surface, and the parts, in which the side surfaces are positioned in the through hole, are not easy to be invaded by water vapor, thereby being beneficial to improving the reliability and service life of the piezoelectric element, the piezoelectric device and the electronic equipment comprising the piezoelectric device.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments/modes of the present invention, the drawings needed to be used in the description of the embodiments/modes are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments/modes of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
Fig. 1A is a schematic front view of a conventional piezoelectric element fixed on a circuit board.
Fig. 1B is a schematic top view of a conventional piezoelectric element fixed on a circuit board.
Fig. 2 is a schematic perspective view of a piezoelectric device according to a first embodiment of the present invention.
Fig. 3 is a schematic sectional view of the piezoelectric device shown in fig. 2 along the line III-III.
Fig. 4 is a schematic sectional view of the piezoelectric device shown in fig. 2 along line IV-IV in a second embodiment.
Fig. 5 is a schematic sectional view of the piezoelectric device shown in fig. 2 taken along line V-V.
Fig. 6A is a schematic perspective view of a resistance strain gauge.
FIG. 6B is an exploded view of the electrical strain gage shown in FIG. 6A.
FIG. 7 is an equivalent circuit diagram of the stress sensing assembly shown in FIG. 5.
Fig. 8 is a schematic structural view of a keypad including the piezoelectric device shown in fig. 2.
Description of the main elements
The following detailed description will further illustrate the invention in conjunction with the above-described figures.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a detailed description of the present invention will be given below with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention, and the described embodiments are merely a subset of the embodiments of the present invention, rather than a complete embodiment. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Unless defined otherwise, 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
Referring to fig. 2 to 3, fig. 2 is a schematic perspective view of a piezoelectric device 10 according to a first embodiment of the present invention, and fig. 3 is a schematic cross-sectional view of the piezoelectric device 10 shown in fig. 2 along line III-III. The piezoelectric device 10 provided by the invention can realize the interconversion between electric energy and mechanical energy, and can be widely applied to various electronic devices, such as touch panels, keyboards and other fields. The electronic device may further comprise a power supply for providing a voltage signal, such as an excitation voltage, to the piezoelectric device 10, and a processor for analyzing an output signal of the piezoelectric device 10.
The piezoelectric device 10 includes an encapsulation layer 110, a metal-based printed circuit board 130, and a piezoelectric element 150. The metal-based printed circuit board 130 includes a metal plate 131 and a circuit board 134 disposed on the metal plate 131. The circuit board 134 includes a first top surface 1341 facing away from the metal plate 131 and a first bottom surface 1342 adjacent to the metal plate 131, wherein the first top surface 1341 is disposed opposite to the first bottom surface 1342. The circuit board 134 forms a through hole 134a penetrating through the thickness direction thereof, that is, the through hole 134a penetrates through the first top surface 1341 and the first bottom surface 1342. The piezoelectric element 150 is configured to vibrate under the driving of the excitation voltage provided by the power supply, and is at least partially accommodated in the through hole 134 a. Specifically, the piezoelectric element 150 includes a second top surface 151 facing away from the metal plate 131 and a second bottom surface 152 adjacent to the metal plate 131.
The piezoelectric element 150 is at least partially received in the through hole 134 a. In one embodiment, the second top surface 151 does not protrude above the first top surface 1341. For example, the second top surface 151 is flush with the first top surface 1341, so that five surfaces of the piezoelectric element 150 except the second top surface 151 are completely accommodated in the through hole 134 a. The piezoelectric element 150 is connected to a plurality of side surfaces between the second top surface 151 and the second bottom surface 152, the metal-based printed circuit board 130 is packaged at the periphery of the second bottom surface 152, and the circuit board 134 is packaged at the periphery of the part, located in the through hole 134a, of the plurality of side surfaces, so that the second bottom surface 152 and the plurality of side surfaces located in the through hole 134a are not easily invaded by moisture, the area of the surface, which is easily invaded by moisture, of the piezoelectric element 150 is favorably reduced, and the service lives of the piezoelectric element 150 and the piezoelectric device 10 are prolonged. The encapsulation layer 110 covers the second top surface 151 and extends to the circuit board 134 around the piezoelectric element 150, and in one embodiment, the encapsulation layer 110 is a pressure sensitive adhesive layer.
In an embodiment, the distance from the second top surface 151 to the metal plate 131 is smaller than the distance from the first top surface 1341 to the metal plate 131, that is, the second top surface 151 of the piezoelectric element 150 is lower than the first top surface 1341 of the circuit board 134, the encapsulation layer 110 covers the second top surface 151, so that the outer surface of the encapsulation layer 110 is flush with the first top surface 1341, on one hand, the area of the surface of the piezoelectric element 150, which is easily penetrated by moisture, is favorably reduced, on the other hand, the area of the surface of the circuit board 134, which corresponds to the piezoelectric element 150, is flat, and the encapsulation layer 110 has a uniform thickness and is not easily damaged.
In one embodiment, the piezoelectric element 150 is partially received in the through hole 134a, the piezoelectric element 150 includes a plurality of side surfaces disposed between the second top surface 151 and the second bottom surface 152, each side surface is at least partially located in the through hole 134a, and the second bottom surface 152 and the portion of each side surface received in the through hole 134a are not easily penetrated by moisture.
The conventional piezoelectric element 150 has a rectangular parallelepiped shape or other shapes and has sharp corners, and the piezoelectric device 10 provided in this embodiment at least partially accommodates the piezoelectric element 150 in the through hole 134a, that is, the second bottom surface 152 and the plurality of side surfaces of the piezoelectric element 150 accommodated in the through hole 134a are not easily penetrated by moisture, which is beneficial to improving the reliability and the service life of the piezoelectric element 150, the piezoelectric device 10 and the electronic apparatus including the piezoelectric device 10.
The metal-based printed circuit board 130 has a metal plate 131 disposed on a circuit board 134 to improve heat dissipation performance of the metal-based printed circuit board 130. In one embodiment, the metal plate 131 is 304 stainless steel or 316 stainless steel. The metal plate 131 and the circuit board 134 are connected by an insulating heat conduction layer 132, and in one embodiment, the heat conduction layer 132 may be a glass fiber layer or a heat conduction resin layer pre-impregnated with polypropylene (PP), and the thickness is less than 100 um.
The side of the heat conductive layer 132 facing away from the metal plate 131 is provided with a plurality of electrodes, such as copper electrodes, for electrically connecting to the circuit board 134 and/or the piezoelectric element 150 to form an electrically conductive path. Wherein at least some of the electrodes are adjacent to the circuit board 134 and the piezoelectric element 150 is electrically connected to at least two of the electrodes through the adhesive layer 140. The process of forming the electrodes on the heat conductive layer 132 is the same as that of the conventional PCB, i.e. the PI film with copper foil is bonded to the metal plate 131, and then the copper foil is patterned. In the present embodiment, the adhesive layer 140 is provided with a non-conductive film (NCF).
The circuit board 134 is a multilayer printed circuit board comprising multiple layers of FR-4 material, with adjacent layers of FR-4 material secured by adhesive bonding. Conductive traces are disposed on the circuit board 134, such as vias 1343 disposed on the circuit board 134 in fig. 3, and electrically connected to an electrode, in one embodiment, at least one layer of FR-4 material has a conductive copper foil disposed thereon, and in this case, the through holes 134a may be formed in a region of the circuit board 134 that does not include conductive traces. In one embodiment, the circuit board 134 does not have a conductive trace therein, and accordingly, the circuit board 134 is directly connected to the metal plate 131 through the heat conductive layer 132, and the plurality of electrodes are sandwiched between the adhesive layer 140 and the heat conductive layer 132.
Further, a piezoelectric element 150 is disposed on the plurality of electrodes, the piezoelectric element 150 includes a piezoelectric ceramic layer 155 and a first electrode 156 and a second electrode 157 covering two ends of the piezoelectric ceramic layer 155, respectively, and the first electrode 156 and the second electrode 157 are used for transmitting a voltage signal, such as an excitation voltage. The piezoelectric ceramic layer 155 is driven by a potential difference between the first electrode 156 and the second electrode 157 to generate mechanical vibration, and resonates with the metal plate 131. The plurality of electrodes include a third electrode 1331 and a fourth electrode 1332 respectively corresponding to the first electrode 156 and the second electrode 157, the first electrode 156 is used for being electrically connected with the third electrode 1331, the second electrode 157 is used for being electrically connected with the fourth electrode 1332, and the third electrode 1331 and the fourth electrode 1332 are used for transmitting a voltage signal output by a power source, such as an excitation voltage, to the first electrode 156 and the second electrode 157 and/or transmitting the voltage signal output by the first electrode 156 and the second electrode 157 to a processor. The first electrode 156 and the second electrode 157 may be electrically connected to a plurality of electrodes, respectively, and the number is not limited.
Specifically, the first electrode 156 and the second electrode 157 are disposed at intervals, and both the first electrode 156 and the second electrode 157 are counter electrodes. That is, the first electrode 156 includes a first segment 156a and a second segment 156b covering the top surface and the bottom surface of the piezoceramic layer 155, respectively, and a third segment 156c connecting the first segment 156a and the second segment 156 b. The second electrode 157 includes a first segment 157a and a second segment 157b covering the top surface and the bottom surface of the piezoceramic layer 155, respectively, and a third segment 157c connecting the first segment 157a and the second segment 157 b. In one embodiment, the adhesive layer 140 is conductive in a direction perpendicular to the metal plate 131 and is insulating in a direction parallel to the metal plate 131, such as Anisotropic Conductive Film (ACF), to electrically connect the second segment 156b with the third electrode 1331 and electrically connect the second segment 157b with the fourth electrode 1332.
A first groove 134b is formed among the third electrode 1331, the circuit board 134 and the first electrode 156, and a second groove 134c is formed among the fourth electrode 1332, the circuit board 134 and the second electrode 157. The heat conduction layer 132 and the metal plate 131 are used as a part of the bottom walls of the first groove 134b and the second groove 134c, the young modulus of the metal plate 131 is greater than 150GPa, which is favorable for reducing the probability of deformation of the metal-based printed circuit board 130, the third electrode 1331 and the fourth electrode 1332 are used as the other part of the bottom walls of the first groove 134b and the second groove 134c, the third section 156c and the third section 157c are respectively used as the side walls of the first groove 134b and the second groove 134c, so as to respectively realize the electrical connection between the third section 156c and the third electrode 1331, and the electrical connection between the third section 157c and the fourth electrode 1332.
In one embodiment, the first groove 134b and the second groove 134c are filled with a conductive medium 135, such as a conductive silver paste filled by a dropping method, and the conductive silver paste electrically connects the third section 156c and the third electrode 1331, and the third section 157c and the fourth electrode 1332.
It is understood that the electrodes of the piezoelectric element 150 can be electrically connected to the third electrode 1331 and the fourth electrode 1332 through the adhesive layer 140 and/or the conductive medium 135.
Fig. 4 is a schematic cross-sectional view of the piezoelectric device 10 shown in fig. 2 along the line IV-IV in a second embodiment. For convenience, the same components are labeled with the same reference numerals. The adhesive layer 141 between the piezoelectric element 150 and the heat conductive layer 132 includes a first conductive adhesive layer 141a and a second conductive adhesive layer 141b, the first electrode 156 is electrically connected to the third electrode 1331 through the first conductive adhesive layer 141a, and the second electrode 157 is electrically connected to the fourth electrode 1332 through the second conductive adhesive layer 141 b. The first conductive adhesive layer 141a and the second conductive adhesive layer 141b are both provided with conductive adhesive, such as isotropic conductive adhesive (ICF), and a non-conductive adhesive layer 141c is further provided between the first conductive adhesive layer 141a and the second conductive adhesive layer 141 b. In one embodiment, the non-conductive adhesive layer 141c is omitted from the first conductive adhesive layer 141a and the second conductive adhesive layer 141 b.
The first groove 134b and the second groove 134c are not filled with the conductive medium 135 (fig. 3), and in one embodiment, the first groove 134b and the second groove 134c may be filled with the conductive medium 135, which is beneficial to reduce the internal resistance of the piezoelectric device 10.
Referring to fig. 5 in conjunction with fig. 2 and 3, fig. 5 is a schematic cross-sectional view of the piezoelectric device 10 shown in fig. 2 along the V-V line. In this embodiment, the piezoelectric device 10 further includes two stress sensing elements 160 for outputting corresponding feedback voltages according to the vibration frequency and intensity of the metal-based printed circuit board 130, and the two stress sensing elements 160 are respectively disposed on two sides of the piezoelectric element 150. The stress sensing element 160 is formed on a side of the heat conductive layer 132 facing away from the metal plate 131, so as to be formed on the same layer as the plurality of electrodes including the third electrode 1331 and the fourth electrode 1332. In one embodiment, the piezoelectric device 10 may be provided with one or another number of stress sensing assemblies 160.
In the field of stress testing, a strain gauge is generally applied, fig. 6A is a schematic perspective view of a resistance strain gauge 50, and fig. 6B is a schematic exploded view of the resistance strain gauge 50 shown in fig. 6A. The resistive strain gauge 50 includes a cap layer 51, a sensitive gate 52 and a substrate 53 stacked in sequence. The base 53 may be provided with a double-sided adhesive film to facilitate attachment to the member. The sensitive grid 52 is a conductive pattern made of a conductive or semi-conductive material, the shape of which is not limited to the "bow" shape shown in fig. 6. When the device is used, the resistance strain gauge 50 is firmly adhered to a component, after the component is stressed, the sensitive grid 52 deforms along with the stress, so that the resistance of the sensitive grid changes, and the resistance change is measured by a special instrument and converted into a strain value of the component.
Referring again to fig. 5, the stress sensing device 160 of the present invention is different from the resistive strain gauge 50 of fig. 5 in structure. Specifically, each stress sensing assembly 160 includes an active sensitivity grid R1 and a compensation sensitivity grid R4, and preferably, the active sensitivity grid R1 and the compensation sensitivity grid R4 are both wire windings formed by copper/nickel-chromium alloy, and the wire winding patterns are the same. The arrangement directions of the active sensitive grids R1 and the compensation sensitive grids R4 are mutually orthogonal. Referring to fig. 5 and 7 in combination, fig. 7 is an equivalent circuit diagram of the stress sensing element 160 shown in fig. 5. The equivalent circuit of the stress sensing assembly 160 is a half-bridge measuring circuit, and the active sensitive gate R1, the compensation sensitive gate R4, and the internal resistances R2 and R3 of the stress sensing assembly form a bridge arm. Specifically, two ends of the active sensitive gate R1 are respectively adjacent to the compensation sensitive gate R4 and the internal resistance R2, two ends of the active sensitive gate R1 and the compensation sensitive gate R4, which are not in contact with each other, output the feedback voltage Vout, and two ends of the active sensitive gate R1 and the internal resistance R2, which are not in contact with each other, are connected to the input voltage Vin. The input voltage Vin and the feedback voltage Vout are electrically connected to the power supply and the processor through electrodes, respectively.
The resistances of the active sensitive gate R1, the compensation sensitive gate R4, and the internal resistances R2 and R3 of the stress sensing device are R1, R2, R3, and R4, respectively, and the feedback voltage Vout satisfies formula 1:
assuming that R1-R2-R3-R4-R and the active sensing grid R1 generates an increase Δ R of resistance under the action of strain, the feedback voltage Vout is positively correlated with the increase Δ R of resistance, and formula 2 is satisfied:
referring to fig. 8, fig. 8 is a schematic structural diagram of a keyboard 60 including the piezoelectric device 10 shown in fig. 2. The keyboard 60 is preferably a flat keyboard as shown in fig. 8, it being understood that the keyboard 60 may also be other types of keyboards.
The keyboard 60 includes a projection device 61 and a cover plate 62, and a plurality of piezoelectric devices 10, a power source (not shown) and a processor (not shown) disposed on the cover plate 62. The power supply is used for providing voltage signals, such as an excitation voltage and an input voltage Vin, for the piezoelectric devices 10, and the processor is used for calculating the pressure magnitude of the pressing operation according to the received feedback voltages output by the plurality of piezoelectric devices 10.
The present invention also provides a method for manufacturing a piezoelectric device 10, including the steps of:
s1: the circuit board 134 is fabricated, and a through hole 134a for accommodating the piezoelectric element 150 is formed in the thickness direction of the circuit board 134, for example, multiple layers of FR-4 materials may be bonded to each other to obtain a multi-layer circuit board, and the adhesive may be a glass fiber layer or a heat-conducting resin layer pre-impregnated with polypropylene (PP). If the circuit board 134 has a position, such as the via 1343, that needs to be opened and filled with copper, a predetermined distance is required to be kept between the via 1343 and the through hole 134a to ensure the mechanical strength of the circuit board 134.
S2: the metal plate 131 and the piezoelectric element 150 are provided, and the piezoelectric element 150 includes a first electrode 156 and a second electrode 157 covering one end thereof, respectively.
S3: a heat conducting layer 132 and a plurality of electrodes are formed on the metal plate 131, wherein the heat conducting layer 132 is formed between the metal plate 131 and the plurality of electrodes, the plurality of electrodes include a third electrode 1331 and a fourth electrode 1332 respectively corresponding to the first electrode 156 and the second electrode 157, and the first electrode 156 and the second electrode 157 of the piezoelectric element 150 are correspondingly adhered to the surfaces of the third electrode 1331 and the fourth electrode 1332. In one embodiment, a copper foil is formed on the PI film, the PI film with the copper foil is bonded to the thermally conductive layer 132, and the copper foil is subsequently patterned to form a plurality of electrodes. In one embodiment, conductive patterns for forming the active sensitive gate R1 and the compensation sensitive gate R4 are also patterned on the same layer of the plurality of electrodes.
S4: the circuit board 134 is bonded to the side of the metal plate 131 where the plurality of electrodes are disposed, so that at least a portion of the piezoelectric element 150 is accommodated in the through hole 134a, a first recess 134b is formed among the third electrode 1331, the circuit board 134 and the first electrode 156, and a second recess 134c is formed among the fourth electrode 1332, the circuit board 134 and the second electrode 157.
S5: the first groove 134b and the second groove 134c are filled with a conductive medium 135 by a dropping method and cured, and the conductive medium 135 is preferably conductive silver paste.
S6: the package layer 110 is formed on the piezoelectric element 150 and the surface of the circuit board 134 facing away from the metal plate 131. Preferably, the encapsulation layer is a pressure sensitive adhesive, such as an acrylic pressure sensitive adhesive psa (pressure sensitive adhesive).
The above-mentioned technical solutions applied to the piezoelectric device 10 may be applied to the manufacturing method of the piezoelectric device 10, and are not described herein again. According to the piezoelectric device 10 provided by the invention, the piezoelectric element 150 is at least accommodated in the through hole 134a, that is, at least part of the side surfaces between the second top surface 151 and the second bottom surface 152 of the piezoelectric element 150 are accommodated in the through hole 134a, and the second bottom surface 152 and the part of each side surface accommodated in the through hole 134a of the piezoelectric element 150 are not easily penetrated by moisture, which is beneficial to improving the reliability and service life of the piezoelectric element 150, the piezoelectric device 10 and the electronic equipment comprising the piezoelectric device 10.
It should be noted that, within the scope of the spirit or the basic features of the present invention, the embodiments applicable to the respective modes can be mutually applicable, and for the sake of brevity and avoidance of repetition, detailed description is omitted here.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned. Furthermore, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. Several of the means recited in the apparatus claims may also be embodied by one and the same means or system in software or hardware. The terms first, second, etc. are used to denote names, but not any particular order. "connected" means that two elements are connected in contact or in the alternative, the two elements are connected together by other elements.
Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (9)
1. A piezoelectric device, comprising:
the metal-based printed circuit board comprises a metal plate and a circuit board arranged on the metal plate, wherein the circuit board comprises a first top surface arranged away from the metal plate, and a through hole is formed in the circuit board and penetrates through the first top surface to face the surface of the metal plate;
the piezoelectric element is used for generating vibration under the driving of an excitation voltage, is at least partially accommodated in the through hole and comprises a second top surface arranged to be away from the metal plate;
the packaging layer covers the second top surface and extends to the circuit board around the piezoelectric element;
the insulating heat conduction layer is arranged on the metal plate; and
the piezoelectric element is connected with the at least two electrodes through the bonding layer.
2. A piezoelectric device according to claim 1, wherein the piezoelectric element includes a piezoceramic layer, and first and second electrodes respectively covering both ends of the piezoceramic layer, and among the plurality of electrodes, third and fourth electrodes respectively provided in correspondence with the first and second electrodes are included, the first electrode being adapted to be electrically connected to the third electrode, and the second electrode being adapted to be electrically connected to the fourth electrode.
3. A piezoelectric device according to claim 2, wherein a first recess is formed between the third electrode, the circuit board, and the first electrode, a second recess is formed between the fourth electrode, the circuit board, and the second electrode, and a conductive medium is filled in each of the first recess and the second recess.
4. A piezoelectric device according to claim 3, wherein the adhesive layer is provided with a non-conductive glue.
5. A piezoelectric device according to claim 2 or 3, wherein the adhesive layer is conductive in a direction perpendicular to the metal plate and insulating in a direction parallel to the metal plate.
6. A piezoelectric device according to claim 2 or 3, wherein the adhesive layer comprises a first layer of conductive glue and a second layer of conductive glue, the first electrode being electrically connected to the third electrode via the first layer of conductive glue, the second electrode being electrically connected to the fourth electrode via the second layer of conductive glue.
7. A piezoelectric device according to any one of claims 1 to 4, further comprising a stress sensing component for outputting a corresponding feedback voltage in dependence on the frequency and intensity of vibration of the metal-based printed circuit board.
8. An electronic device comprising a piezoelectric device according to any one of claims 1 to 7, the electronic device comprising a power supply for supplying the piezoelectric device with the excitation voltage and a processor for analyzing an output signal of the piezoelectric device.
9. The electronic device of claim 8, wherein the electronic device is a flat keyboard, the flat keyboard further comprising a cover for receiving a pressing operation, the cover having a plurality of piezoelectric devices disposed thereon, and the processor is configured to calculate the magnitude of the pressing operation based on the received feedback voltages output by the plurality of piezoelectric devices.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811331276.2A CN109494294B (en) | 2018-11-09 | 2018-11-09 | Piezoelectric device and electronic apparatus |
| TW107140936A TWI710148B (en) | 2018-11-09 | 2018-11-16 | Piezoelectric device and electronic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811331276.2A CN109494294B (en) | 2018-11-09 | 2018-11-09 | Piezoelectric device and electronic apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109494294A CN109494294A (en) | 2019-03-19 |
| CN109494294B true CN109494294B (en) | 2022-06-21 |
Family
ID=65694147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811331276.2A Active CN109494294B (en) | 2018-11-09 | 2018-11-09 | Piezoelectric device and electronic apparatus |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN109494294B (en) |
| TW (1) | TWI710148B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110162174B (en) * | 2019-05-16 | 2022-05-13 | 业成科技（成都）有限公司 | Tactile feedback and sensing device |
| CN214256810U (en) * | 2020-12-09 | 2021-09-21 | 华为技术有限公司 | Piezoelectric ceramic waterproof structure, piezoelectric ceramic device and electronic equipment |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107032291A (en) * | 2016-01-21 | 2017-08-11 | 奥特斯奥地利科技与***技术有限公司 | The MEMS piezoelectric transducers formed at PCB supporting constructions |
| WO2017160296A1 (en) * | 2016-03-17 | 2017-09-21 | Intel Corporation | Package integrated piezoelectric haptic actuators |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10013058B2 (en) * | 2010-09-21 | 2018-07-03 | Apple Inc. | Touch-based user interface with haptic feedback |
| TW201246023A (en) * | 2011-05-03 | 2012-11-16 | Yao-Tsung Tang | Touch pressure sensing module |
| EP2662909A1 (en) * | 2012-05-08 | 2013-11-13 | Aito B.V. | A piezoelectric device |
| KR102016489B1 (en) * | 2014-12-02 | 2019-09-02 | 삼성전기주식회사 | Printed circuit board and manufacturing method thereof |
| US10423253B2 (en) * | 2017-04-20 | 2019-09-24 | Htc Corporation | Handheld electronic apparatus, touch sensor and touch detection method thereof |
-
2018
- 2018-11-09 CN CN201811331276.2A patent/CN109494294B/en active Active
- 2018-11-16 TW TW107140936A patent/TWI710148B/en active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107032291A (en) * | 2016-01-21 | 2017-08-11 | 奥特斯奥地利科技与***技术有限公司 | The MEMS piezoelectric transducers formed at PCB supporting constructions |
| WO2017160296A1 (en) * | 2016-03-17 | 2017-09-21 | Intel Corporation | Package integrated piezoelectric haptic actuators |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109494294A (en) | 2019-03-19 |
| TW202018980A (en) | 2020-05-16 |
| TWI710148B (en) | 2020-11-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI338125B (en) | Arrayed electrostatic capacitance sensor | |
| JP5605433B2 (en) | Piezoelectric vibration device | |
| US7181977B2 (en) | Sensor assembly with lead attachment | |
| CN109494294B (en) | Piezoelectric device and electronic apparatus | |
| CN108235748B (en) | Piezoresistive sensor, pressure detection device, and electronic apparatus | |
| US20090265927A1 (en) | Input device and its manufacturing method | |
| JP6004123B2 (en) | Method for manufacturing piezoelectric sensor | |
| US8256292B2 (en) | Acceleration sensor with surface protection | |
| JP2015118032A (en) | Inspection method of piezoelectric sensor | |
| JP2020053433A (en) | Strain sensor resistor | |
| JP4822769B2 (en) | Acceleration sensor | |
| JP6342896B2 (en) | 1-up 1-down connection structure for piezoelectric elements in tire patches | |
| CN211956411U (en) | Touch feedback module and electronic equipment | |
| JP3805644B2 (en) | Piezoelectric actuator | |
| CN214474934U (en) | Touch feedback module and electronic equipment | |
| JPWO2015098723A1 (en) | Method for manufacturing piezoelectric sensor | |
| CN210629449U (en) | Piezoelectric module and electronic equipment | |
| JP6324803B2 (en) | Pressure-sensitive sensor and manufacturing method thereof | |
| JP5346684B2 (en) | Piezoelectric generator unit | |
| JP2004184127A (en) | Stress sensor | |
| WO2022215462A1 (en) | Pressure-sensitive switch | |
| WO2020179731A1 (en) | Vibration sensor | |
| CN215954276U (en) | Touch pad and electronic equipment | |
| CN215954278U (en) | Touch pad and electronic equipment | |
| CN113778245B (en) | Touch pad and electronic equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |