Bone conduction packaging structure

Abstract

The utility model provides a bone conduction packaging structure, which includes: a substrate, a shell that is covered with the substrate to form a receiving space, a bone conduction MEMS chip and an ASIC chip arranged in the receiving space, the bone conduction MEMS chip includes a substrate with a cavity, a diaphragm supported on the substrate, and a back plate that is spaced apart and arranged on the side of the diaphragm away from the substrate, a first cavity is formed between the diaphragm and the back plate, a second cavity is formed between the diaphragm and the substrate, and a third cavity is formed between the back plate and the shell, the substrate, and the substrate, and the first cavity is set as a low-pressure area below atmospheric pressure. The bone conduction packaging structure of the utility model sets the area between the diaphragm and the back plate as a low-pressure area to reduce the damping between the diaphragm and the back plate, thereby improving the performance of the bone conduction packaging structure.

Description

[Technical field]

[0001] The utility model relates to the field of sound-to-electricity conversion, in particular to a bone conduction packaging structure. [Background technology]

[0002] The bone conduction microphone converts the slight vibrations of the head and neck bones caused by people speaking into electrical signals. Since it collects sound through air conduction unlike traditional microphones, it can restore the sound with high clarity even in noisy environments, thus avoiding the noise interference caused by airborne sound and ensuring extremely high sound quality.

[0003] In the related art, the bone conduction packaging structure includes a housing, a circuit board that is surrounded by the housing to form a receiving space, a vibration component and a MEMS chip that are arranged in the receiving space, and the vibration component includes a vibration plate that is arranged opposite to the circuit board and spaced apart, a frame that connects the vibration component and the circuit board, and a mass block that is arranged on the vibration component. When the bone conduction packaging structure is working, the housing receives a vibration signal or a pressure signal, and the vibration plate and the mass block are excited by the vibration signal or the pressure signal, and the mass block and the vibration plate vibrate, so that the gas in the receiving space vibrates, so that the air pressure in the receiving space changes, and the MEMS detects this air pressure change, and converts the sensed information into a detectable electrical signal, which is transmitted to the circuit board. However, the bone conduction packaging structure of the related art is large in size and has poor performance.

[0004] Therefore, it is necessary to provide a new bone conduction packaging structure to solve the above technical problems. [Contents of the utility model]

[0005] The purpose of the utility model is to provide a bone conduction packaging structure with better performance.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the utility model is as follows: a bone conduction packaging structure, the bone conduction packaging structure comprising: a substrate, a shell covering the substrate to form a receiving space, a bone conduction MEMS chip and an ASIC chip arranged in the receiving space, the bone conduction MEMS chip comprising a substrate having a cavity, a diaphragm supported on the substrate, and a back plate spaced apart from the diaphragm on a side away from the substrate, a first cavity is formed between the diaphragm and the back plate, a second cavity is formed between the diaphragm and the substrate and the substrate, a third cavity is formed between the back plate and the shell, the substrate and the substrate, and the first cavity is set as a low-pressure area below atmospheric pressure.

[0007] Preferably, the diaphragm and the back plate are both complete and airtight structures.

[0008] Preferably, the diaphragm is provided with a first air hole, the first air hole connects the first cavity and the second cavity, and the second cavity is set as a low-pressure area lower than the atmospheric pressure.

[0009] Preferably, the back plate is provided with a second air vent, the second air vent connects the first cavity and the third cavity, and the third cavity is set as a low-pressure area lower than the atmospheric pressure.

[0010] Preferably, the diaphragm is provided with a first air hole, the first air hole connects the first cavity and the second cavity, the second cavity is set as a low-pressure area lower than the atmospheric pressure, and the back plate is provided with a second air hole, the second air hole connects the first cavity and the third cavity, and the third cavity is set as a low-pressure area lower than the atmospheric pressure.

[0011] Preferably, a mass block is provided on a side of the diaphragm away from the back plate.

[0012] Preferably, the bone conduction MEMS chip further comprises a connecting post connecting the mass block to a side of the diaphragm away from the back plate.

[0013] Preferably, an anti-sticking protrusion is provided on a side of the back plate close to the diaphragm.

[0014] Compared with the related art, the bone conduction packaging structure provided by the utility model comprises: a substrate, a shell that is covered with the substrate to form a receiving space, a bone conduction MEMS chip and an ASIC chip disposed in the receiving space, the bone conduction MEMS chip comprises a substrate having a cavity, a diaphragm supported on the substrate, and a back plate that is spaced apart and disposed on the side of the diaphragm away from the substrate, a first cavity is formed between the diaphragm and the back plate, a second cavity is formed between the diaphragm and the substrate and the substrate, a third cavity is formed between the back plate and the shell, the substrate and the substrate, and the first cavity is set as a low-pressure area below atmospheric pressure. The bone conduction packaging structure of the utility model does not separately set a vibration plate and a mass block to detect air pressure changes, but directly detects air pressure changes through the bone conduction MEMS chip, thereby reducing the volume of the bone conduction packaging structure, and at the same time, the area between the diaphragm and the back plate is set as a low-pressure area to reduce the damping between the diaphragm and the back plate, thereby improving the performance of the bone conduction packaging structure.

Brief Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in the field of the present invention, other drawings can be obtained based on these drawings without creative work, among which:

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the bone conduction MEMS chip in the bone conduction packaging structure of the utility model;

[0017] Figure 2 for Figure 1 An exploded view of the bone conduction MEMS chip shown;

[0018] Figure 3 It is a cross-sectional view of the bone conduction packaging structure of the first embodiment of the utility model;

[0019] Figure 4 A cross-sectional view of a bone conduction packaging structure according to a second embodiment of the present invention;

[0020] Figure 5 A cross-sectional view of a bone conduction packaging structure according to a third embodiment of the present invention;

[0021] Figure 6 It is a cross-sectional view of the bone conduction packaging structure of the fourth embodiment of the present invention. [Specific implementation method]

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] See also Figures 1 to 3 , which is a bone conduction packaging structure 100 of the first embodiment provided by the utility model, and the bone conduction packaging structure 100 includes: a substrate 1, a shell 2 covering the substrate 1 to form a receiving space 10, and a bone conduction MEMS chip 3 and an ASIC chip 4 arranged in the receiving space 10.

[0024] The substrate 1 is a circuit board, and the housing 2 can be a metal housing.

[0025] The bone conduction MEMS chip 3 includes: a substrate 31 having a cavity 310, a diaphragm 32 supported on the substrate 31, a back plate 33 arranged at a distance from the diaphragm 32 on the side away from the substrate 31, and a mass block 34 arranged on the side of the diaphragm 32 away from the back plate 33. The mass block 34 and the substrate 31 are made of the same material. The bone conduction MEMS chip 3 also includes a connecting column 35 connecting the mass block 34 to the side of the diaphragm 32 away from the back plate 33. The connecting column 35 can be a whole piece of structure or a plurality of structures. The mass block 34 is located in the cavity 310. The diaphragm 32 is fixed to the substrate 31 by a plurality of supporting columns 321. The diaphragm 32 and the supporting columns 321 are integrally formed. An anti-sticking protrusion 331 is arranged on the side of the back plate 33 close to the diaphragm 32. The anti-sticking protrusion 331 can prevent the diaphragm 32 from adhering to the back plate 33 when the diaphragm 32 vibrates.

[0026] The utility model directly arranges the mass block 34 on the diaphragm 32 of the bone conduction MEMS chip 3, so that the sensitivity of the bone conduction MEMS chip 3 can be flexibly adjusted by directly adjusting the size of the mass block 34, and the utility model has strong practicality. At the same time, the bone conduction packaging structure 100 provided by the utility model avoids the need to separately arrange a vibration plate and a mass block in the receiving space 10, thereby reducing the cost, simplifying the packaging, and making the structure smaller.

[0027] A first cavity 36 is formed between the diaphragm 32 and the back plate 33, a second cavity 37 is formed between the diaphragm 32 and the substrate 31 and the base plate 1, and a third cavity 38 is formed between the back plate 33 and the shell 2, the substrate 31 and the base plate 1. In the present embodiment, the diaphragm 32 and the back plate 33 are both complete and airtight structures to seal the first cavity 36, and the first cavity 36 is set as a low-pressure zone below atmospheric pressure. Such a setting can reduce the damping between the diaphragm 32 and the back plate 33, thereby improving the performance of the bone conduction packaging structure 100.

[0028] See also Figure 4 , which is a bone conduction packaging structure 100a of the second embodiment provided by the utility model. The difference between the second embodiment and the first embodiment is that, in the second embodiment, the diaphragm 32a is provided with a first air hole 322a, and the first air hole 322a connects the first cavity 36a and the second cavity 37a, and the second cavity 37a is further set to a low-pressure area lower than the atmospheric pressure. Such a setting can reduce the damping between the diaphragm 32a and the back plate 33a, thereby improving the performance of the bone conduction packaging structure 100a.

[0029] See also Figure 5, which is a bone conduction packaging structure 100b of the third embodiment provided by the utility model. The difference between the third embodiment and the first embodiment is that, in the third embodiment, the back plate 33b is provided with a second air hole 332b, and the second air hole 332b connects the first cavity 36b and the third cavity 38b. The third cavity 38b is further set to a low-pressure area lower than the atmospheric pressure. Such a setting can reduce the damping between the diaphragm 32b and the back plate 33b, thereby improving the performance of the bone conduction packaging structure 100b.

[0030] See also Figure 6 , which is a bone conduction packaging structure 100c of the fourth embodiment provided by the utility model. The difference between the fourth embodiment and the first embodiment is that, in the fourth embodiment, the diaphragm 32c is provided with a first air hole 322c, and the first air hole 322c connects the first cavity 36c and the second cavity 37c, and the back plate 33c is provided with a second air hole 332c, and the second air hole 332c connects the first cavity 36c and the third cavity 38c. In this way, the first cavity 36c, the second cavity 37c and the third cavity 38 are connected together, and the second cavity 37c is further set to a low-pressure zone below atmospheric pressure, and the third cavity 38c is also further set to a low-pressure zone below atmospheric pressure. Such a setting can reduce the damping between the diaphragm 32c and the back plate 33c, thereby improving the performance of the bone conduction packaging structure 100c.

[0031] Compared with the related art, the bone conduction packaging structure provided by the utility model comprises: a substrate, a shell that covers the substrate to form a receiving space, a bone conduction MEMS chip and an ASIC chip disposed in the receiving space, the bone conduction MEMS chip comprises a substrate having a cavity, a diaphragm supported on the substrate, and a back plate that is spaced apart and disposed on the side of the diaphragm away from the substrate, a first cavity is formed between the diaphragm and the back plate, a second cavity is formed between the diaphragm and the substrate and the substrate, a third cavity is formed between the back plate and the shell, the substrate and the substrate, and the first cavity is set as a low-pressure area below atmospheric pressure. The bone conduction packaging structure of the utility model does not separately set a vibration plate and a mass block to detect air pressure changes, but directly detects air pressure changes through a MEMS chip, thereby reducing the volume of the bone conduction packaging structure, and at the same time setting the area between the diaphragm and the back plate as a low-pressure area to reduce the damping between the diaphragm and the back plate, thereby improving the performance of the bone conduction packaging structure.

[0032] The above is only an implementation method of the present invention. It should be pointed out that a person skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements are all within the protection scope of the present invention.

Claims

1. A bone conduction packaging structure, comprising: A substrate, a shell covering the substrate to form a receiving space, a bone conduction MEMS chip and an ASIC chip arranged in the receiving space, wherein the bone conduction MEMS chip includes a substrate with a cavity, a diaphragm supported on the substrate, and a back plate spaced apart from the diaphragm on a side away from the substrate, characterized in that a first cavity is formed between the diaphragm and the back plate, a second cavity is formed between the diaphragm and the substrate and the substrate, a third cavity is formed between the back plate and the shell, the substrate and the substrate, and the first cavity is set as a low-pressure area below atmospheric pressure.

2. The bone conduction packaging structure according to claim 1, characterized in that: The diaphragm and the back plate are both complete and airtight structures.

3. The bone conduction packaging structure according to claim 1, characterized in that: The diaphragm is provided with a first air hole, the first air hole connects the first cavity and the second cavity, and the second cavity is set as a low-pressure area lower than atmospheric pressure.

4. The bone conduction packaging structure according to claim 1, characterized in that: The back plate is provided with a second air vent, the second air vent connects the first cavity and the third cavity, and the third cavity is set as a low-pressure area lower than the atmospheric pressure.

5. The bone conduction packaging structure according to claim 1, characterized in that: The diaphragm is provided with a first air hole, the first air hole connects the first cavity and the second cavity, the second cavity is set as a low-pressure area lower than the atmospheric pressure, the back plate is provided with a second air hole, the second air hole connects the first cavity and the third cavity, the third cavity is set as a low-pressure area lower than the atmospheric pressure.

6. The bone conduction packaging structure according to claim 1, characterized in that: A mass block is arranged on a side of the diaphragm away from the back plate.

7. The bone conduction packaging structure according to claim 6, characterized in that: The bone conduction MEMS chip further includes a connecting post connecting the mass block to a side of the diaphragm away from the back plate.

8. The bone conduction packaging structure according to claim 1, characterized in that: An anti-sticking protrusion is arranged on one side of the back plate close to the diaphragm.

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