A sensor

Abstract

This invention provides a sensor belonging to the field of acoustic technology, comprising a circuit board, a housing on one side of the circuit board, at least one diaphragm on the side of the circuit board located inside the housing, adjacent diaphragms being connected by metal connecting ribs, and an ASIC chip. Electrode rings are provided on the diaphragms, and the electrode rings are connected to the ASIC chip via metal wires. This invention forms a sensor through the thin film and the first copper foil layer of the circuit board, simplifying the structure and making the packaging process simpler while ensuring performance. It breaks through the traditional MEMS design and process barriers, thereby improving efficiency and saving costs. The diaphragm thickness is greater than that of MEMS technology diaphragms, resulting in better mechanical reliability.

Description

Technical Field

[0001] This utility model relates to a sensor. Background Technology

[0002] Silicon microphones and the resulting electronic cigarette microphones, serving as acoustic-electric sensors and micro-pressure differential airflow sensors, are increasingly being used in the consumer electronics market. Their main component, the MEMS sensor, is manufactured using semiconductor technology, offering significant advantages in consistency and reliability, which has gained widespread consumer acceptance. In recent years, the pursuit of ultimate cost-effectiveness in consumer electronics has become a trend, leading to the development of various solutions, but often with limited success.

[0003] Existing sensor packaging methods are shown in the appendix. Figure 1 In this system, MEMS serves as the sensor component. Its diaphragm and back plate form a parallel plate capacitor. When a sound signal is transmitted, it causes the diaphragm to vibrate, changing the capacitance of the parallel plate capacitor and generating a tiny electrical signal. This signal is then processed by an ASIC and output, thus completing the sound-to-electric conversion process.

[0004] Existing MEMS solutions use silicon as the wafer substrate and are fabricated using processes such as photolithography, deposition, etching, doping, and plating, similar to integrated circuit manufacturing. This ensures consistency and reliability, but comes at the cost of higher costs. Furthermore, due to their design, the introduction of minute foreign objects can lead to functional failure. Therefore, both wafer-level manufacturing and finished product packaging require higher cleanliness levels, necessitating at least Class 1000 or even Class 100 cleanrooms, further increasing the final cost. On the other hand, MEMS are limited by the fab's process platform, with film thickness typically in the hundreds of nanometers. This results in insufficient mechanical reliability, and film breakage has become a major source of market feedback issues. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the above-mentioned traditional technologies and provide a sensor.

[0006] The purpose of this utility model is achieved through the following technical measures: a sensor, including a circuit board, with a housing on one side of the circuit board, characterized in that: at least one diaphragm is provided on the side of the circuit board located inside the housing, adjacent diaphragms are connected by metal connecting ribs, and an ASIC chip is also provided, with an electrode ring provided on the diaphragm, and the electrode ring is connected to the ASIC chip by a metal wire.

[0007] As an improvement, the diaphragm is bonded to the circuit board via an adhesive layer.

[0008] As a further improvement, the circuit board includes a first isolation layer, a first copper foil layer on one side of the first isolation layer, a substrate layer on the other side of the first copper foil layer, a second copper foil layer on the other side of the substrate layer, and a second isolation layer on the other side of the second copper foil layer.

[0009] As a further improvement, the adhesive layer is located between the diaphragm and the first isolation layer; or in the triangular area between the end face of the diaphragm and the upper plane of the first isolation layer; or between the diaphragm and the first copper foil layer.

[0010] As a further improvement, the diaphragm includes a thin film connected to the circuit board; it also includes a conductive layer connected to the electrode ring.

[0011] As a further improvement, the diaphragm is also provided with vent holes, and anti-stick protrusions are provided on the underside of the film.

[0012] As a further improvement, the substrate layer is provided with a potential connection hole, and the circuit board is also provided with a disconnect hole, which passes through the first copper foil layer, the substrate layer and the second copper foil layer.

[0013] As a further improvement, the circuit board has small holes corresponding to the area below the diaphragm.

[0014] As a further improvement, the electrode ring includes a support body, on which an electrode connection portion is provided. One end of the electrode connection portion is connected to the conductive layer, and the other end is connected to the metal wire.

[0015] As a further improvement, a mass block is provided above the diaphragm.

[0016] Due to the adoption of the above technical solution, the advantages of this utility model compared with the prior art are:

[0017] First: This novel sensor is formed by the thin film and the first copper foil layer of the circuit board. While ensuring performance, it simplifies the structure and makes the packaging process simpler, breaking through the traditional MEMS design and process barriers, thereby improving efficiency and saving costs.

[0018] Second: The gap between the diaphragm and the first copper foil layer is larger than that of MEMS technology. The first copper foil layer serves as a back electrode plate, electrical connection and electrode. Using the thin film instead of the MEMS diaphragm is relatively less sensitive to foreign objects, so the requirements for the purification level are not high. Overall, it is beneficial to cost and improves the process and the yield of the whole machine.

[0019] Third: The thickness of the diaphragm is greater than that of the diaphragm in MEMS technology, resulting in better mechanical reliability;

[0020] Fourth: The dimensions and gaps of this new design can be adjusted to optimize and improve performance, breaking the fixed pattern of MEMS technology solutions.

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0022] Appendix Figure 1 This is a structural diagram of the background technology;

[0023] Appendix Figure 2 This is a structural schematic diagram of Embodiment 1 of the present invention;

[0024] Appendix Figure 3 It is attached Figure 2 A magnified view of a portion of the image;

[0025] Appendix Figure 4 These are schematic diagrams of different structures of the electrode ring described in Embodiment 1 of this utility model;

[0026] Appendix Figure 5 This is a schematic diagram of another structure of the electrode ring described in Embodiment 1 of this utility model;

[0027] Appendix Figure 6 This is a schematic diagram of the structure of Embodiment 2 of this utility model;

[0028] Appendix Figure 7 This is a structural schematic diagram of Embodiment 3 of this utility model;

[0029] Appendix Figure 8 This is a structural schematic diagram of Embodiment 4 of this utility model;

[0030] Appendix Figure 9 This is a structural schematic diagram of Embodiment 5 of this utility model;

[0031] Appendix Figure 10 This is a structural schematic diagram of Embodiment Six of this utility model;

[0032] Appendix Figure 11 This is a structural schematic diagram of Embodiment Seven of this utility model. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0035] In this utility model, unless otherwise explicitly specified and limited, the terms "installation", "setting", "connection", "fixing", "screw connection", etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. Example

[0037] As attached Figure 2-5 As shown: A sensor includes a circuit board 1, with a housing 2 on one side of the circuit board 1. The housing 2, serving as a protective layer for the main internal components, can be made of materials such as metal, plastic, fiberglass, or LCP, and is fixed with solder paste or adhesive. A diaphragm 3 is located on one side of the circuit board 1 inside the housing 2, and an ASIC chip 4 is also provided. An electrode ring 5 is provided on the diaphragm 3, and the electrode ring 5 is connected to the ASIC chip 4 via a metal wire 6. The diaphragm 3 is bonded to the circuit board 1 by an adhesive layer 7. The adhesive layer 7 is located between the diaphragm 3 and the first isolation layer 11. The adhesive layer 7 can be made of high-temperature adhesives such as epoxy resin, or other high-temperature resistant adhesives.

[0038] The diaphragm 3 includes a thin film 31, which is composed of PSS, PET, silicon-based material or other thin film material, and a metal plate. The thin film 31 is connected to the circuit board 1. It also includes a conductive layer 32, which conducts electricity and is connected to the electrode ring 5. The diaphragm 3 forms one pole of the parallel plate capacitor, and the diaphragm 3 is fixed to the electrode ring 5 by a coating process.

[0039] The circuit board 1 includes a first isolation layer 11, a first copper foil layer 12 on one side of the first isolation layer 11, and a substrate layer 13 on the other side of the first copper foil layer 12. The substrate layer 13 can be composed of materials such as FR4, ceramic, and aluminum substrate. A second copper foil layer 14 is provided on the other side of the substrate layer 13, and a second isolation layer 15 is provided on the other side of the second copper foil layer 14. The first isolation layer 11 and the second isolation layer 15 are typically composed of solder mask to protect the internal circuitry. The first copper foil layer 12 and the second copper foil layer 14 can be etched into circuitry to achieve electrical connections. The second copper foil layer 14 is an outer copper foil layer used to form client pads and basic circuit connections. The first copper foil layer 12 is an inner copper foil layer that serves as a back electrode, forming the other pole of a parallel plate capacitor and leading out pad electrodes. Electrical connections can be achieved through gold wires.

[0040] The circuit board 1 has a small hole 9 at the position below the diaphragm 3, which serves as a sound pickup or airflow passage and can reduce the vibration damping of the diaphragm 3.

[0041] The gap of the parallel plate capacitor is determined by the adhesive layer 7 and the first insulating layer 11, and the C0 value can be adjusted by changing the thickness of the adhesive layer 7 and / or the first insulating layer 11.

[0042] The electrode ring 5 includes a support body 51, which is made of non-metallic materials such as plastic, glass fiber, or LCP. The support body 51 has an electrode connection portion 52, which can be disposed inside the support body 51 (as shown in the attached figure). Figure 9 (as shown), one side (as attached) Figure 5 As shown, when located on one side, the electrode connection portion includes a metal strip 521, the outer side of which is coated with a plating layer 522. The plating layer 522 is made of the same material as the conductive layer 22 and is electrically conductive. Alternatively, the outer periphery (as shown in the attached diagram) may also be included. Figure 3 As shown in the figure, one end of the electrode connection part 52 is connected to the conductive layer 32, and the other end is connected to the metal wire 6.

[0043] As attached Figure 4 As shown: The electrode ring 5 is wider at the top and narrower at the bottom, which reduces the contact area at the bottom of the electrode ring 5, reduces parasitic capacitance, and improves performance. Example

[0044] As attached Figure 6 As shown, the structure is the same as in Embodiment 1, except that the diaphragm 3 is bonded to the circuit board 1 by an adhesive layer 7; the adhesive layer 7 is located between the diaphragm 3 and the first copper foil layer 12.

[0045] The gap of the parallel plate capacitor is determined by the adhesive layer 7, and the C0 value can be adjusted by changing the thickness of the adhesive layer 7. Example

[0046] As attached Figure 7 As shown, the structure is the same as in Embodiment 1, except that the diaphragm 3 is bonded to the circuit board 1 by an adhesive layer 7; the adhesive layer 7 is located in the triangular area between the end face of the diaphragm 3 and the upper plane of the first isolation layer 11.

[0047] The gap between the parallel plate capacitors is determined by the first isolation layer 11. The C0 value can be adjusted by changing the thickness of the first isolation layer 11. This embodiment can optimize the gap consistency, and the synchronization gap can be made smaller, further improving the sensitivity. Example

[0048] As attached Figure 8 As shown, the structure is the same as that in Embodiment 1, except that: the substrate layer 13 is provided with a potential connection hole 131, which realizes the same potential and reduces the parasitic capacitance between the first copper foil layer 12 and the second copper foil layer 14.

[0049] The circuit board 1 is also provided with a disconnect hole 132, which passes through the first copper foil layer 12, the substrate layer 13 and the second copper foil layer 14, and disconnects the first copper foil layer 12 corresponding to the back electrode plate from the second copper foil layer 14 connected to other circuits through the disconnect hole 132, so as to avoid the parasitic capacitance generated by the copper foil extending to all sides. Example

[0050] As attached Figure 9 As shown, the structure is the same as that in Embodiment 3, except that: the conductive layer 32 of the diaphragm 3 is a polycrystalline silicon layer, the thin film 31 is a silicon dioxide thin film or a silicon nitride thin film, the diaphragm 3 is also provided with a vent hole 33, and the thin film is provided with an anti-stick protrusion 34 below to prevent the diaphragm 3 and the back electrode from sticking together under a large impact. Example

[0051] As attached Figure 10 As shown, the structure is the same as that in Embodiment 1, except that: a mass block 10 is provided above the diaphragm 3. The mass block is achieved by means of bonding or electroplating, and can be used as a VPU to achieve vibration pickup. Example

[0052] As attached Figure 11 As shown, the structure is the same as that in Embodiment 1, except that: the circuit board 1 has four diaphragms 3 on one side inside the housing. The overall shape of the diaphragms 3 can be square or round. Adjacent diaphragms 3 are connected by metal connecting ribs to realize the conduction between different diaphragms 3 and between the diaphragms 3 and the electrodes.

[0053] Due to the influence of the film size, thickness and tension, the frequency response resonance peak is located relatively early, which cannot meet the high bandwidth requirements. The optimization scheme changes a single diaphragm 3 to multiple diaphragms 3, which is beneficial to shift the high frequency resonance peak to the back and can achieve a larger bandwidth.

[0054] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A sensor, comprising a circuit board, wherein a housing is provided on one side of the circuit board, characterized in that: The circuit board has at least one diaphragm on one side inside the housing. Adjacent diaphragms are connected by metal connecting ribs. An ASIC chip is also provided. Electrode rings are provided on the diaphragms. The electrode rings are connected to the ASIC chip by metal wires.

2. The sensor according to claim 1, characterized in that: The diaphragm is bonded to the circuit board via an adhesive layer.

3. The sensor according to claim 2, characterized in that: The circuit board includes a first isolation layer, a first copper foil layer on one side of the first isolation layer, a substrate layer on the other side of the first copper foil layer, a second copper foil layer on the other side of the substrate layer, and a second isolation layer on the other side of the second copper foil layer.

4. A sensor according to claim 3, characterized in that: The adhesive layer is located between the diaphragm and the first isolation layer; or in the triangular area between the end face of the diaphragm and the upper plane of the first isolation layer; or between the diaphragm and the first copper foil layer.

5. A sensor according to claim 1, characterized in that: The diaphragm includes a thin film connected to the circuit board; it also includes a conductive layer connected to the electrode ring.

6. A sensor according to claim 5, characterized in that: The diaphragm is also provided with vent holes, and anti-stick protrusions are provided on the underside of the film.

7. A sensor according to claim 3, characterized in that: The substrate layer is provided with a potential connection hole, and the circuit board is also provided with a disconnect hole, which passes through the first copper foil layer, the substrate layer and the second copper foil layer.

8. A sensor according to claim 7, characterized in that: The circuit board has a small hole below the diaphragm.

9. A sensor according to claim 5, characterized in that: The electrode ring includes a support body, on which an electrode connection portion is provided. One end of the electrode connection portion is connected to the conductive layer, and the other end is connected to the metal wire.

10. A sensor according to claim 1, characterized in that: A mass block is positioned above the diaphragm.

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