Sound generating device, vibration element and method for making the same

Abstract

The present invention provides a method for preparing a vibration element, comprising the following steps: forming a photoresist on at least one surface of a vibration diaphragm; processing the photoresist to obtain a patterned photoresist, wherein a plurality of passages are exposed in the patterned photoresist; forming a metal layer on the patterned photoresist, and part of the metal layer is also filled in the passage; forming a graphene oxide layer on the metal layer, and part of the graphene oxide layer is also filled in the passage; removing the patterned photoresist, the metal layer on the patterned photoresist, and the graphene oxide layer; and reducing the graphene oxide circuit to a reduced graphene oxide circuit to obtain a plurality of spaced voice coil circuits, wherein the gap between two adjacent voice coil circuits is 8μm to 20μm. The gap between two adjacent voice coil circuits of the present invention is relatively small. The present invention also provides a vibration element and a sound generating device.

Description

Technical Field

[0001] The present invention relates to the technical field of sound generating devices, and in particular to a sound generating device, a vibration element and a preparation method thereof. Background Art

[0002] The sound generating device usually includes a vibrating diaphragm and a voice coil circuit. The sound generating principle of the sound generating device is to use electromagnetic force to convert energy to generate sound, that is, to generate a changing electromagnetic field by controlling the current of the voice coil circuit in a fixed magnetic field, and drive the vibrating diaphragm to vibrate and generate sound. A magnet / magnetic group is set on one or both sides of the vibrating diaphragm. When the voice coil circuit is connected to the alternating audio current, the voice coil circuit in the orthogonal magnetic field is acted upon by the electromagnetic force in the vertical direction, driving the vibrating diaphragm to vibrate and generate sound, generating sufficient thrust on the vibrating diaphragm, thereby pushing the air to generate sound.

[0003] Based on the sound generation principle and structure of the above-mentioned sound generating device, on the one hand, the electromagnetic force generated by the voice coil circuit is required to be as large as possible. According to the electromagnetic force formula F=BLI (where B is the magnetic field strength, L is the length of the coil circuit in the magnetic field, and I is the magnitude of the alternating current), in addition to increasing the magnetic field strength B, it is also necessary to increase the length L of the coil circuit in the magnetic field. For this reason, there are reports that voice coil circuits are designed on both sides of the vibration diaphragm, and the upper and lower layers of the voice coil circuits are connected by "spot welding" or "punching + conductive glue" on both sides of the vibration diaphragm to achieve the purpose of increasing the length L of the coil circuit. However, for extremely thin vibration diaphragms (i.e., thickness less than 6μm), the voice coil circuits of the upper and lower layers of the vibration diaphragm are easily penetrated or welded by spot welding or "punching + conductive glue" in the middle area of ​​the vibration diaphragm, and the product yield is extremely low. In addition, spot welding and conductive glue will increase the weight of the vibration diaphragm, affecting the sensitivity of the vibration diaphragm and other sound generation performance. On the other hand, the voice coil circuit is required to be evenly distributed on the vibration diaphragm, and the larger the distribution area of ​​the voice coil circuit within a limited area, the better. This will cause the entire surface of the vibration diaphragm to be affected by the electromagnetic force and vibrate synchronously, reducing or avoiding swinging and split vibration.

[0004] In short, no matter for the design of single-sided voice coil circuit or double-sided voice coil circuit, within the limited vibrating diaphragm area, the gap between two adjacent voice coil circuits in the voice coil circuit should be as small as possible and the circuit distribution area should be as large as possible. This will help to increase the length and line width of the voice coil circuit at the same time, without increasing or even decreasing the line resistance, and ultimately increase the electromagnetic force generated by the voice coil circuit in the sound generating device to the limit. Summary of the invention

[0005] Based on this, it is necessary to provide a method for preparing a vibration element with a small gap between two adjacent voice coil circuits.

[0006] In addition, it is also necessary to provide a vibration element prepared by the above preparation method.

[0007] In addition, it is also necessary to provide a sound generating device including the above-mentioned vibration element.

[0008] In one aspect, the present invention provides a method for preparing a vibration element, comprising the following steps:

[0009] forming a photoresist on at least one surface of the vibrating diaphragm;

[0010] sequentially exposing and developing the photoresist to obtain a patterned photoresist, wherein a plurality of vias are exposed in the patterned photoresist, the vias are exposed to the vibration diaphragm, and the shortest distance between the side walls of two adjacent vias is 8 μm to 20 μm;

[0011] forming a metal layer on the patterned photoresist, and a portion of the metal layer is also filled in the via;

[0012] forming a graphene oxide layer on the metal layer, and a portion of the graphene oxide layer is also filled in the via;

[0013] removing the patterned photoresist, the metal layer on the patterned photoresist, and the graphene oxide layer on the patterned photoresist, so that the metal layer in the via forms a metal circuit, and the graphene oxide layer in the via forms a graphene oxide circuit; and

[0014] The graphene oxide circuit is reduced to a reduced graphene oxide circuit to obtain a plurality of voice coil circuits distributed at intervals, wherein a gap between two adjacent voice coil circuits is 8 μm to 20 μm.

[0015] In some embodiments, before forming the photoresist on at least one surface of the vibrating diaphragm, the preparation method further comprises:

[0016] forming a peelable film on one surface of the vibrating diaphragm;

[0017] Wherein, the strippable film and the photoresist are respectively located on different surfaces of the vibration diaphragm;

[0018] After sequentially exposing and developing the photoresist, and before or after forming the metal layer on the patterned photoresist, the preparation method further includes:

[0019] The peelable film is removed.

[0020] In some embodiments, forming the photoresist on at least one surface of the vibrating diaphragm specifically comprises the following steps:

[0021] The photoresist is formed on at least one surface of the vibration membrane by spin coating, roll coating or thermal bonding and heating and drying.

[0022] In some embodiments, forming the graphene oxide layer on the metal layer specifically comprises the following steps:

[0023] The graphene oxide layer is formed on the metal layer by using an electrostatic spraying process.

[0024] In some embodiments, forming the graphene oxide layer on the metal layer using an electrostatic spraying process specifically includes the following steps:

[0025] Spraying the graphene oxide dispersion liquid through a nozzle in an electrostatic spray device, and splitting the sprayed graphene oxide dispersion liquid into graphene oxide droplets; and

[0026] The graphene oxide liquid droplets fall on the metal layer to form the graphene oxide layer.

[0027] In some embodiments, the metal layer is prepared by evaporation or sputtering, and the material of the metal layer includes at least one of copper, aluminum, aluminum-zinc alloy, nickel, silver and gold.

[0028] In some of the embodiments, before forming the photoresist on at least one surface of the vibration diaphragm, the vibration diaphragm is subjected to plasma roughening treatment in a roll-to-roll manner.

[0029] In some embodiments, the thickness of the patterned photoresist is less than 20 μm.

[0030] In some of the embodiments, the voice coil circuit is prepared on one surface or both surfaces of the vibrating diaphragm.

[0031] Another aspect of the present invention provides a vibration element prepared by the above-mentioned method for preparing a vibration element, wherein the thickness of the vibration membrane is 0.5 μm to 6 μm.

[0032] In some of the embodiments, the thickness of the metal circuit is 1 nm to 20 nm; and / or the thickness of the reduced graphene oxide circuit is less than 50 nm.

[0033] In some embodiments, the vibration diaphragm includes an insulating film, and the material of the insulating film includes at least one of polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide and polypropylene.

[0034] In some of the embodiments, the conductivity of the voice coil line is greater than or equal to 200 S / CM.

[0035] In another aspect, the present invention provides a sound generating device, comprising a magnetic body. The sound generating device further comprises the above-mentioned vibration element, wherein the vibration element and the magnetic body are arranged apart from each other.

[0036] In some embodiments, the sound generating device also includes a plurality of gaskets and a shell, the vibration element is located between the magnetic body and the shell, at least one of the gaskets is located between the magnetic body and the vibration element, and at least another gasket is located between the vibration element and the shell.

[0037] The present invention exposes and develops the photoresist to obtain the patterned photoresist. Since the shortest distance between the side walls of two adjacent passages in the patterned photoresist is 8μm to 20μm, the gap between two adjacent voice coil circuits prepared by the patterned photoresist is also 8μm to 20μm, thereby realizing the preparation of a voice coil circuit with an extreme gap, maximizing the distribution area of ​​the voice coil circuit, increasing the length and line width of the voice coil circuit, and not increasing or even decreasing the resistance of the voice coil circuit, so that the electromagnetic force generated by the voice coil circuit is increased to the limit, and the electromagnetic force generated by the voice coil circuit is more optimally and synchronously vibrated to the vibration diaphragm, avoiding or reducing the influence of swing and split vibration, thereby facilitating the voice coil circuit to better drive the vibration diaphragm to sound. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A cross-sectional view of a vibrating diaphragm provided in accordance with a first embodiment of the present invention;

[0039] Figure 2 For Figure 1 A cross-sectional view of a vibrating diaphragm after a peelable film is formed on one surface thereof;

[0040] Figure 3 For Figure 2 A cross-sectional view of the vibrating diaphragm after photoresist is formed on the other surface thereof;

[0041] Figure 4 For Figure 3 The photoresist shown is a cross-sectional view after exposure and development treatment in sequence;

[0042] Figure 5 For the general Figure 4 A cross-sectional view showing the peelable film removed;

[0043] Figure 6 For Figure 5 A cross-sectional view of a patterned photoresist after a metal layer is formed thereon;

[0044] Figure 7 For Figure 6A cross-sectional view of a metal layer after a graphene oxide layer is formed on the metal layer;

[0045] Figure 8 It is a schematic diagram of forming a graphene oxide layer by electrostatic spraying in the present invention;

[0046] Fig. 9 For the general Figure 7 A cross-sectional view showing a patterned photoresist, a metal layer on the patterned photoresist, and a graphene oxide layer on the patterned photoresist after removal;

[0047] Fig.10 For the general Fig. 9 A cross-sectional view of a vibration element obtained after reduction of the graphene oxide circuit shown;

[0048] Fig.11 A cross-sectional view of a vibration element provided for a second embodiment of the present invention;

[0049] Fig.12 A cross-sectional view of a sound generating device provided by a first embodiment of the present invention;

[0050] Fig.13 A cross-sectional view of a sound generating device provided in accordance with a second embodiment of the present invention.

[0051] Icons: 10-vibrating diaphragm; 11-peelable film; 20-photoresist; 30-patterned photoresist; 31-path; 40-metal layer; 50-graphene oxide layer; 60-needle; 61-nozzle; 70-metal circuit; 71-graphene oxide circuit; 80-reduced graphene oxide circuit; 90-voice coil circuit; 91-conductive part; 100, 200-vibrating element; 300, 400-sound generating device; 310-support; 320-magnetic body; 330-shell; 340-gasket. DETAILED DESCRIPTION

[0052] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0054] A first embodiment of the present invention provides a method for preparing a vibration element, comprising the following steps:

[0055] Step S11, please refer to Figure 1 , the vibration diaphragm 10 is subjected to plasma roughening treatment.

[0056] Specifically, the vibrating diaphragm 10 may be subjected to plasma roughening treatment in a roll-to-roll manner to improve the subsequent metal layer (see Figure 6 ) and the bonding force between the vibration diaphragm 10.

[0057] In one embodiment, the thickness of the vibration diaphragm 10 is 0.5 μm to 6 μm. Preferably, the thickness of the vibration diaphragm 10 is 0.5 μm to 4 μm. In one embodiment, the vibration diaphragm 10 includes an insulating film. In one embodiment, the material of the insulating film includes at least one of polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS) and polypropylene (PP).

[0058] Step S12, please refer to Figure 2 A peelable film 11 is formed on one surface of the processed vibration membrane 10 .

[0059] The peelable film 11 and the vibrating membrane 10 form a uniform and peelable bonding force by electrostatic adsorption or rolling polymer glue. In one embodiment, the peelable film 11 can be an organic polymer base film. In one embodiment, the thickness of the peelable film 11 can be 12 μm to 100 μm.

[0060] Step S13, please refer to Figure 3 , a photoresist 20 is formed on the other surface of the processed vibration membrane 10 .

[0061] Specifically, the photoresist 20 can be formed on the other surface of the vibration membrane 10 by spin coating, roll coating, thermal bonding, heating and drying. In one embodiment, the thickness of the photoresist 20 is less than 20 μm. Preferably, the thickness of the photoresist 20 is less than 2 μm.

[0062] Step S14, please refer to Figure 4 , the photoresist 20 is sequentially exposed and developed to obtain a patterned photoresist 30 .

[0063] A plurality of vias 31 are exposed in the patterned photoresist 30, and the vias 31 are exposed to the vibration membrane 10. The shortest distance D between the side walls of two adjacent vias 31 is 8 μm to 20 μm.

[0064] It can be understood that, since the thickness of the photoresist 20 is less than 20 μm, the thickness of the patterned photoresist 30 formed by the photoresist 20 after exposure and development is also less than 20 μm. Preferably, the thickness of the patterned photoresist 30 is also less than 2 μm.

[0065] Step S15, please refer to Figure 5 , remove the peelable film 11.

[0066] It is understandable that step S15 may also be placed at the end, that is, step S15 may be placed after step S16, after step S17, after step S18, or after step S19.

[0067] Step S16, please refer to Figure 6 A metal layer 40 is formed on the patterned photoresist 30 , and a portion of the metal layer 40 is also filled in the via 31 .

[0068] That is, the metal layer 40 is formed on the entire surface of the patterned photoresist 30. Specifically, the metal layer 40 can be formed on the patterned photoresist 30 by evaporation or sputtering. The surface of the patterned photoresist 30 away from the vibration diaphragm 10 is completely covered by the metal layer 40. It can be understood that the metal layer 40 filled in the passage 31 is in contact with the vibration diaphragm 10.

[0069] In one embodiment, the thickness of the metal layer 40 in the through hole 31 is 1 nm to 20 nm. In one embodiment, the material of the metal layer 40 is at least one of copper, aluminum, aluminum-zinc alloy, nickel, silver and gold.

[0070] Step S17, please refer to Figure 7 , a graphene oxide layer 50 is formed on the metal layer 40 , and a portion of the graphene oxide layer 50 is also filled in the via 31 .

[0071] That is, the entire graphene oxide layer 50 is formed on the metal layer 40 , and the graphene oxide layer 50 filled in the via 31 is also located on the metal layer 40 .

[0072] Please also read Figure 8 In one embodiment, the graphene oxide layer 50 is formed on the metal layer 40 by electrostatic spraying.

[0073] Specifically, a graphene oxide dispersion is prepared, and the graphene oxide dispersion is sprayed out through the nozzle 61 of the needle 60 in the electrostatic spray device. Under the action of a strong external electric field and a Maxwell stress perpendicular to and tangential to the graphene oxide dispersion, the shape of the sprayed graphene oxide dispersion changes to an inverted cone (also known as a Taylor cone). The jet drawn from the tip of the inverted cone-shaped graphene oxide dispersion automatically splits into relatively uniform graphene oxide droplets under the action of surface tension. The graphene oxide droplets fall on the metal layer 40 to form the graphene oxide layer 50 with a relatively uniform thickness. By adjusting the flow rate of the graphene oxide dispersion sprayed out by the electrostatic spray device, the temperature of the metal layer 40, and the distance between the nozzle 61 and the metal layer 40, it can be determined whether a dry graphene oxide layer 50 or a wet graphene oxide layer 50 is formed when the graphene oxide droplets contact the metal layer 40. If a wet graphene oxide layer 50 is formed, a dry graphene oxide layer 50 can be obtained after drying.

[0074] In one embodiment, based on the patterned photoresist 30, the graphene oxide layer 50 is covered or prepared on the metal layer 40 (i.e., the metal layer 40 located on the patterned photoresist 30 and the metal layer 40 located in the passage 31) in its entirety or selectively by controlling the nozzle 61 in the electrostatic spray device to move along the X-axis direction or along the Y-axis direction.

[0075] In one embodiment, the shape of the graphene oxide layer 50 in the via 31 includes at least one of a zigzag line, a concentric circle, a nearly concentric circle, and a spiral line.

[0076] In one embodiment, the graphene oxide layer 50 in the via 31 has a thickness less than 50 nm.

[0077] Step S18, please refer to Fig. 9 , the patterned photoresist 30, the metal layer 40 on the patterned photoresist 30, and the graphene oxide layer 50 on the patterned photoresist 30 are removed, so that the metal layer 40 in the via 31 forms a metal circuit 70, and the graphene oxide layer 50 in the via 31 forms a graphene oxide circuit 71.

[0078] Specifically, the patterned photoresist 30 can be removed by a stripping solution such as a strong base NaOH or an organic solvent or a swelling agent, thereby removing the metal layer 40 on the patterned photoresist 30 and the graphene oxide layer 50 on the patterned photoresist 30. After removal, the remaining metal layer 40 (i.e., the metal layer 40 located in the via 31) forms the metal circuit 70, and the remaining graphene oxide layer 50 (i.e., the graphene oxide layer 50 located in the via 31) forms the graphene oxide circuit 71.

[0079] It can be understood that, since the thickness of the metal layer 40 located in the through hole 31 is 1nm-20nm, the thickness of the metal line 70 formed by the metal layer 40 located in the through hole 31 is also 1nm-20nm. Similarly, since the thickness of the graphene oxide layer 50 located in the via 31 is less than 50nm, the thickness of the graphene oxide line 71 formed by the graphene oxide layer 50 located in the via 31 is also less than 50nm.

[0080] Step S19, please refer to Fig.10 , the graphene oxide circuit 71 is reduced to a reduced graphene oxide circuit 80 to obtain a plurality of voice coil circuits 90 , thereby obtaining a vibration element 100 .

[0081] Specifically, the graphene oxide circuit 71 is immersed in a reducing solution to reduce the graphene oxide circuit 71 to the reduced graphene oxide circuit 80, thereby obtaining the voice coil circuit 90 and thus obtaining the vibration element 100. In one embodiment, the reducing solution may be hydroiodic acid (HI).

[0082] The gap D between two adjacent voice coil circuits 90 is also 8 μm to 20 μm.

[0083] It can be understood that since the shape of the graphene oxide circuit 71 includes at least one of a tortuous line, a concentric circle, an approximately concentric circle and a spiral line, the shape of the reduced graphene oxide circuit 80 obtained by reducing the graphene oxide circuit 71 also includes at least one of a tortuous line, a concentric circle, an approximately concentric circle and a spiral line.

[0084] Similarly, since the thickness of the graphene oxide circuit 71 is less than 50 nm, the thickness of the reduced graphene oxide circuit 80 obtained by reducing the graphene oxide circuit 71 is also less than 50 nm.

[0085] Among them, since the reduced graphene oxide circuit 80 has better conductivity than the graphene oxide circuit 71 , reducing the graphene oxide circuit 71 can improve the conductivity of the vibration element 100 .

[0086] In one embodiment, the conductivity of the voice coil circuit 90 is greater than or equal to 200 S / CM.

[0087] See also Fig.11 The second embodiment of the present invention provides a method for preparing a vibration element. The difference between the method for preparing a vibration element provided by the second embodiment and the method for preparing a vibration element provided by the first embodiment is that:

[0088] Step S12 is omitted.

[0089] In step S13 , the photoresist 20 is formed on two opposite surfaces of the vibration membrane 10 .

[0090] In step S14 , the two photoresists 20 are exposed and developed in sequence to obtain the two patterned photoresists 30 .

[0091] Step S15 is omitted.

[0092] In step S16 , the metal layer 40 is formed on the two patterned photoresists 30 respectively.

[0093] In step S17 , the graphene oxide circuit 50 is formed on the two metal layers 40 respectively.

[0094] In step S18, the two patterned photoresists 30, the metal layers 40 respectively located on the two patterned photoresists 30, and the graphene oxide layers 50 respectively located on the two patterned photoresists 30 are removed respectively, so that the metal layers 40 respectively located in the two passages 31 form the metal circuits 70, and the graphene oxide layers 50 respectively located in the passages 31 form the graphene oxide circuits 71.

[0095] In step S19 , the two graphene oxide circuits 71 are respectively reduced to the reduced graphene oxide circuits 80 to obtain the voice coil circuit 90 .

[0096] In addition, after step S19, a conductive portion 91 needs to be provided on the vibration diaphragm 10. The conductive portion 91 is used to electrically connect the voice coil circuits 90 located on different surfaces of the vibration diaphragm 10. In one embodiment, the conductive portion 91 can be a metallized hole, conductive glue or other conductive materials.

[0097] See also Fig.10The first embodiment of the present invention further provides a vibration element 100 prepared by the preparation method in the first embodiment. The vibration element 100 includes a vibration diaphragm 10 and a plurality of voice coil circuits 90 located on one surface of the vibration diaphragm 10 .

[0098] In one embodiment, the thickness of the vibration diaphragm 10 is 0.5 μm to 6 μm. Preferably, the thickness of the vibration diaphragm 10 is 0.5 μm to 4 μm. In one embodiment, the vibration diaphragm 10 includes an insulating film. In one embodiment, the material of the insulating film includes at least one of polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS) and polypropylene (PP).

[0099] The gap D between two adjacent voice coil circuits 90 is 8 μm to 20 μm. In one embodiment, the electrical conductivity of the voice coil circuit 90 is greater than or equal to 200 S / CM.

[0100] In one embodiment, the voice coil circuit 90 includes a metal circuit 70 and a reduced graphene oxide circuit 80 sequentially stacked on the vibration diaphragm 10 .

[0101] In one embodiment, the thickness of the metal line 70 is 1 nm to 20 nm. In one embodiment, the material of the metal line 70 is at least one of copper, aluminum, aluminum-zinc alloy, nickel, silver and gold.

[0102] In one embodiment, the reduced graphene oxide circuit 80 has a shape including at least one of a winding line, a concentric circle, a nearly concentric circle, and a spiral line. In one embodiment, the reduced graphene oxide circuit 80 has a thickness less than 50 nm.

[0103] See also Fig.11 The second embodiment of the present invention further provides a vibration element 200 prepared by the preparation method in the second embodiment. The difference between the vibration element 200 provided by the second embodiment and the vibration element 100 provided by the first embodiment is that:

[0104] The vibration element 200 further includes another voice coil circuit 90, and the other voice coil circuit 90 is located on the other surface of the vibration diaphragm 10. That is, the two voice coil circuits 90 are respectively located on two opposite surfaces of the vibration diaphragm 10.

[0105] In addition, the vibration element 200 further includes a conductive portion 91, and the conductive portion 91 is located on the vibration diaphragm 10. The conductive portion 91 is used to electrically connect the voice coil circuit 90 located on different surfaces of the vibration diaphragm 10. In one embodiment, the conductive portion 91 can be a metallized hole, conductive glue or other conductive materials.

[0106] See also Fig.12 The first embodiment of the present invention further provides a sound generating device 300 , which includes the vibration element 100 , a support member 310 , a magnetic body 320 , a shell 330 and a gasket 340 .

[0107] In one embodiment, a receiving hole (not shown) is disposed on the support member 310 , wherein the support member 310 is used to receive the magnetic body 320 .

[0108] In one embodiment, the magnetic body 320 is received in the receiving hole so that the magnetic body 320 is fixed on the support member 310. In one embodiment, the magnetic body 320 can be a magnet or a magnetic group. The magnetic body 320 can generate a magnetic field so that the vibration element 100 is subjected to a magnetic force.

[0109] The vibration element 100 and the magnetic body 320 are located on the same side of the support member 310. When the voice coil circuit 90 in the vibration element 100 is connected to the alternating audio current, the voice coil circuit 90 in the orthogonal magnetic field is acted upon by the vertical electromagnetic force and drives the vibration diaphragm 10 to vibrate and generate sound, generating sufficient thrust on the vibration diaphragm 10, thereby pushing the air to generate sound.

[0110] The housing 330 and the vibration element 100 are located on the same side of the support member 310, and the vibration element 100 is located between the housing 330 and the support member 310. The housing 330 is disposed on the vibration element 100 to protect the vibration element 100, thereby preventing the vibration element 100 from being damaged by the outside and contaminated by the outside dust.

[0111] In this embodiment, there are four gaskets 340. Two of the gaskets 340 are located between the vibration element 100 and the housing 330 to isolate the vibration element 100 from the housing 330; the other two gaskets 340 are located between the vibration element 100 and the magnetic body 320 to isolate the vibration element 100 from the magnetic body 320.

[0112] In one embodiment, the sound generating device 400 can be used in headphones, car audio, etc.

[0113] See also Fig.13 The second embodiment of the present invention further provides a sound generating device 400. The difference between the sound generating device 400 provided in the second embodiment and the sound generating device 300 provided in the first embodiment is that:

[0114] The sound generating device 400 does not include the vibration element 100 but includes the vibration element 200 . That is, the vibration element 100 is replaced by the vibration element 200 .

[0115] The present invention has the following beneficial effects:

[0116] First, the present invention exposes and develops the photoresist 20 to obtain the patterned photoresist 30. Since the shortest distance D between the side walls of two adjacent passages 31 in the patterned photoresist 30 is 8μm to 20μm, the gap D between two adjacent voice coil circuits 90 prepared by the patterned photoresist 30 is also 8μm to 20μm, thereby realizing the preparation of a voice coil circuit with a limit gap, maximizing the distribution area of ​​the voice coil circuit 90, increasing the length and line width of the voice coil circuit 90, and the resistance of the voice coil circuit 90 does not increase or even decreases, so that the electromagnetic force generated by the voice coil circuit 90 is increased to the limit, and the electromagnetic force generated by the voice coil circuit 90 can better synchronously vibrate the vibration diaphragm 10, avoiding or reducing the influence of swing and split vibration, thereby facilitating the voice coil circuit 90 to better drive the vibration diaphragm 10 to make sound.

[0117] Secondly, the present invention forms the metal layer 40 with a thickness of 1nm to 20nm on the ultra-thin vibration diaphragm 10 with a thickness of 0.5μm to 6μm, and prepares the reduced graphene oxide circuit 80 with a thickness of less than 50nm on the metal layer 40 by electrostatic spraying, thereby preparing the voice coil circuit 90. Since the metal circuit 70 and the reduced graphene oxide circuit 80 prepared by the metal layer 40 both have an ultra-thin thickness, and the metal circuit 70 and the reduced graphene oxide circuit 80 both have a high electrical conductivity, the voice coil circuit 90 with an ultra-thin thickness and high electrical conductivity is successfully prepared.

[0118] Thirdly, the vibrating diaphragm 10 of the present invention has a thinner thickness (i.e., a thickness of 0.5 μm to 6 μm), a lighter weight, and a higher rigidity, and the electrostatic spraying method of the present invention has a lower thermal impact on the vibrating diaphragm 10, so that the vibrating diaphragm 10 has a higher yield. At the same time, the vibrating diaphragm 10 of the present invention is not easy to deform and distort when making sounds, and presents very high full-band resolution or sensitivity, fast response, and especially very good transient and low-frequency and high-frequency characteristics.

[0119] Finally, the reduced graphene oxide circuit 80 in the voice coil circuit 90 of the present invention has better thermal conductivity. When the voice coil circuit 90 is connected to the current to make a sound, the heat generated by the voice coil circuit 90 is easily dissipated, thereby reducing the problem of the vibration diaphragm 10 becoming soft and the vibration being unstable due to the heat of the voice coil circuit 90.

[0120] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a vibration element, characterized in that: The following steps are involved: forming a photoresist on at least one surface of the vibrating diaphragm; sequentially exposing and developing the photoresist to obtain a patterned photoresist, wherein a plurality of vias are exposed in the patterned photoresist, the vias are exposed to the vibration diaphragm, and the shortest distance between the side walls of two adjacent vias is 8 μm to 20 μm; forming a metal layer on the patterned photoresist, and a portion of the metal layer is also filled in the via; forming a graphene oxide layer on the metal layer, and a portion of the graphene oxide layer is also filled in the via; removing the patterned photoresist, the metal layer on the patterned photoresist, and the graphene oxide layer on the patterned photoresist, so that the metal layer in the via forms a metal circuit, and the graphene oxide layer in the via forms a graphene oxide circuit; and The graphene oxide circuit is reduced to a reduced graphene oxide circuit to obtain a plurality of voice coil circuits distributed at intervals, wherein a gap between two adjacent voice coil circuits is 8 μm to 20 μm.

2. The method for preparing a vibration element according to claim 1, characterized in that: Before forming the photoresist on at least one surface of the vibration diaphragm, the preparation method further includes: forming a peelable film on one surface of the vibration diaphragm; Wherein, the strippable film and the photoresist are respectively located on different surfaces of the vibration diaphragm; After sequentially exposing and developing the photoresist, and before or after forming the metal layer on the patterned photoresist, the preparation method further includes: The peelable film is removed.

3. The method for preparing a vibration element according to claim 1, characterized in that: Forming the photoresist on at least one surface of the vibrating diaphragm specifically comprises the following steps: The photoresist is formed on at least one surface of the vibration membrane by spin coating, roll coating or thermal bonding and heating and drying.

4. The method for preparing a vibration element according to claim 1, characterized in that: Forming the graphene oxide layer on the metal layer specifically comprises the following steps: The graphene oxide layer is formed on the metal layer by using an electrostatic spraying process.

5. The method for preparing a vibration element according to claim 4, characterized in that: The process of forming the graphene oxide layer on the metal layer by electrostatic spraying specifically comprises the following steps: Spraying the graphene oxide dispersion liquid through a nozzle in an electrostatic spray device, and splitting the sprayed graphene oxide dispersion liquid into graphene oxide droplets; and The graphene oxide liquid droplets fall on the metal layer to form the graphene oxide layer.

6. The method for preparing a vibration element according to claim 1, characterized in that: The metal layer is prepared by evaporation or sputtering, and the material of the metal layer includes at least one of copper, aluminum, aluminum-zinc alloy, nickel, silver and gold.

7. The method for preparing a vibration element according to claim 1, characterized in that: Before forming the photoresist on at least one surface of the vibration diaphragm, the vibration diaphragm is subjected to plasma roughening treatment in a roll-to-roll manner.

8. The method for preparing a vibration element according to claim 1, characterized in that: The thickness of the patterned photoresist is less than 20 μm.

9. The method for preparing a vibration element according to any one of claims 1 to 8, characterized in that: The voice coil circuit is prepared on one surface or both surfaces of the vibration diaphragm.

10. A vibration element prepared by the method for preparing a vibration element according to any one of claims 1 to 9, characterized in that: The thickness of the vibration membrane is 0.5 μm to 6 μm.

11. The vibration element according to claim 10, characterized in that The thickness of the metal circuit is 1 nm to 20 nm; and / or the thickness of the reduced graphene oxide circuit is less than 50 nm.

12. The vibration element according to claim 10, characterized in that The vibration membrane includes an insulating film, and the material of the insulating film includes at least one of polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide and polypropylene.

13. The vibration element according to claim 10, characterized in that The electrical conductivity of the voice coil circuit is greater than or equal to 200 S / CM.

14. A sound generating device, comprising a magnetic body, characterized in that: The sound generating device further comprises a vibration element as claimed in any one of claims 10 to 13, wherein the vibration element and the magnetic body are arranged apart from each other.

15. The sound generating device according to claim 14, characterized in that: The sound generating device further comprises a plurality of gaskets and a shell, wherein the vibration element is located between the magnetic body and the shell, at least one of the gaskets is located between the magnetic body and the vibration element, and at least another gasket is located between the vibration element and the shell.

Images