CN112830447B

CN112830447B - MEMS sensor and electronic device

Info

Publication number: CN112830447B
Application number: CN202110072854.0A
Authority: CN
Inventors: 陈岭
Original assignee: Weifang Goertek Microelectronics Co Ltd
Current assignee: Weifang Goertek Microelectronics Co Ltd
Priority date: 2021-01-19
Filing date: 2021-01-19
Publication date: 2023-12-26
Anticipated expiration: 2041-01-19
Also published as: CN112830447A

Abstract

The invention discloses a MEMS sensor and electronic equipment using the same. The MEMS sensor comprises an external packaging structure, an MEMS chip, a waterproof breathable film and a heating module, wherein a containing cavity is formed in the external packaging structure, and ventilation holes communicated with the containing cavity are formed in the external packaging structure; the MEMS chip is arranged in the accommodating cavity and communicated with the air holes; the waterproof breathable film is arranged on the outer surface of the external packaging structure and covers the breathable holes; the heating module is arranged in the ventilation holes and occupies only part of ventilation channels of the ventilation holes. The technical scheme of the invention can enable the MEMS sensor to be quickly recovered after wading.

Description

MEMS sensor and electronic device

Technical Field

The invention relates to the technical field of sensors, in particular to an MEMS sensor and electronic equipment using the same.

Background

In recent years, with the rapid development of technology, microelectromechanical systems (Micro-Electro-Mechanical System, MEMS) have grown. Among them, MEMS sensors have been widely used as detection devices in electronic devices such as mobile phones, notebook computers, tablet computers, wearable devices, and the like.

Currently, there are MEMS sensors, such as MEMS microphones, MEMS gas sensors, MEMS gas pressure sensors, etc., that rely on vents on the outer packaging structure thereof to detect external parameters (e.g., sound, gas pressure, etc.); the MEMS sensor generally realizes waterproof treatment on the ventilation holes by means of a waterproof ventilation film so as to avoid water inflow.

Therefore, although the components in the MEMS sensor can be prevented from being damaged, the MEMS sensor can normally operate; however, the entire MEMS sensor cannot be put into use at once because the waterproof and breathable membrane may still be covered by a water membrane. Therefore, how to enable the MEMS sensor to be quickly recovered after wading becomes a research subject of research personnel.

Disclosure of Invention

The invention mainly aims to provide a MEMS sensor and electronic equipment applying the MEMS sensor, and aims to enable the MEMS sensor to be quickly recovered after wading.

An embodiment of the present invention proposes a MEMS sensor comprising:

the packaging structure comprises an outer packaging structure, wherein a containing cavity is formed in the outer packaging structure, and ventilation holes communicated with the containing cavity are formed in the outer packaging structure;

the MEMS chip is arranged in the accommodating cavity and communicated with the air holes;

the waterproof breathable film is arranged on the outer surface of the outer packaging structure and covers the ventilation holes; and

the heating module is arranged in the ventilation holes and occupies only part of ventilation channels of the ventilation holes.

In an embodiment of the invention, the heating module is a heat transfer element, the MEMS sensor further includes an internal heating element, the internal heating element is disposed in the accommodating cavity, a first heat conduction track is disposed in the external packaging structure, one end of the first heat conduction track contacts with the internal heating element, and the other end contacts with the heat transfer element.

In an embodiment of the invention, the external packaging structure includes a circuit board, the air holes are formed in the circuit board, and the first heat conduction track is arranged in the circuit board.

In an embodiment of the present invention, an inner wall of the ventilation hole is provided with a heat conducting cylinder body that is disposed around, the heat transfer element is disposed in the heat conducting cylinder body and contacts with the inner wall of the heat conducting cylinder body, and one end of the first heat conducting track, which is far away from the internal heating element, contacts with the heat conducting cylinder body.

In an embodiment of the present invention, an outer edge of the heat transfer element is circumferentially disposed along the heat conductive cylinder and contacts an inner wall of the heat conductive cylinder.

In an embodiment of the present invention, the heat transfer element has a plate structure, and the plate structure is provided with a plurality of through holes arranged at intervals.

In an embodiment of the present invention, a second heat conducting track is further provided in the external packaging structure, and one end of the second heat conducting track is in contact with the heat transfer element, and the other end of the second heat conducting track is exposed to the external surface of the external packaging structure and is used for contacting with an external heating element.

In an embodiment of the invention, the heat generating module is a self-heating element, and the external packaging structure includes a circuit board, and the self-heating element is electrically connected to the circuit board.

In an embodiment of the present invention, an adhesive layer is disposed between the waterproof and breathable film and the external packaging structure, and the waterproof and breathable film is adhered to the external surface of the external packaging structure through the adhesive layer.

An embodiment of the present invention also proposes an electronic device including a MEMS sensor, the MEMS sensor including:

According to the technical scheme, the waterproof and breathable film is covered on the outer side of the air hole, and due to the special waterproof and breathable functions of the waterproof and breathable film, the MEMS chip can not be influenced to detect external parameters (such as sound, gas, air pressure and the like) through the air hole, and the function of preventing external moisture from entering the air hole can be achieved, so that the components inside the MEMS sensor are prevented from being damaged, and normal operation can be ensured. Further, according to the technical scheme, a heating module is arranged in the ventilation holes, and the heating module only occupies part of ventilation channels of the ventilation holes; therefore, the MEMS chip is not affected to detect external parameters (e.g., sound, gas, air pressure, etc.) through the vent. Meanwhile, due to the heating function of the heating module, heat can be directly dissipated to the waterproof breathable film, so that water film evaporation covered on the waterproof breathable film is accelerated, and the MEMS sensor can be quickly recovered after wading.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an embodiment of a MEMS sensor according to the present invention;

FIG. 2 is a top view of one embodiment of the circuit board of FIG. 1;

fig. 3 is a top view of another embodiment of the circuit board of fig. 1.

Reference numerals illustrate:

reference numerals	Name of the name	Reference numerals	Name of the name
				100	MEMS sensor	133	Heat conduction cylinder
10	External packaging structure	135	Second heat conduction track
				10a	Storage cavity	20	MEMS chip
10b	Air vent	30	Waterproof breathable film
				11	Housing shell	40	Heating module
13	Circuit board	50	Internal heating element
				131	First heat conduction track	60	Adhesive layer

The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present invention are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "a plurality", "a number" or "a plurality" is at least two, such as two, three, etc., unless specifically defined otherwise.

In the present invention, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical solutions of the embodiments of the present invention may be combined with each other, but it is necessary to be based on the fact that those skilled in the art can implement the technical solutions, and when the technical solutions are contradictory or cannot be implemented, the combination of the technical solutions should be considered as not existing, and not falling within the scope of protection claimed by the present invention.

MEMS sensors generally rely on waterproof breathable films to achieve waterproof treatment of their breathable holes to avoid water ingress.

Therefore, although the components in the MEMS sensor can be prevented from being damaged, the MEMS sensor can normally operate; however, the entire MEMS sensor cannot be put into use at once because the waterproof and breathable membrane may still be covered by a water membrane.

In view of the above technical problems, the present invention provides a MEMS sensor 100, which aims to enable the MEMS sensor 100 to be quickly recovered after wading.

It is understood that the MEMS sensor 100 of the present invention may be applied to electronic devices, such as, but not limited to, mobile phones, notebook computers, tablet computers, personal digital assistants (Personal Digital Assistant, PDA), electronic book readers, MP3 (moving picture experts compression standard audio layer 3,Moving Picture Experts Group Audio Layer III) players, MP4 (moving picture experts compression standard audio layer 4,Moving Picture Experts Group Audio Layer IV) players, wearable devices, navigators, palm game players, etc.

The following description will explain the specific structure of the MEMS sensor 100 according to the present invention in the specific embodiment, and will explain the MEMS sensor 100 by taking the horizontal placement as an example:

as shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, the MEMS sensor 100 includes an external package structure 10, a MEMS chip 20, a waterproof and breathable film 30, and a heat generating module 40.

Wherein, a storage cavity 10a is formed in the outer packaging structure 10, and an air vent 10b communicated with the storage cavity 10a is formed in the outer packaging structure 10; the MEMS chip 20 is disposed in the accommodating cavity 10a and is communicated with the air hole 10b; the waterproof and breathable film 30 is arranged on the outer surface of the outer packaging structure 10 and covers the breathable holes 10b; the heating module 40 is disposed in the ventilation hole 10b, and occupies only a part of ventilation channels of the ventilation hole 10b.

In this embodiment, the external packaging structure 10 includes a housing 11 and a circuit board 13, where the housing 11 is covered on the circuit board 13 and encloses with the circuit board 13 to form a receiving cavity 10a. The MEMS chip 20 is disposed in the receiving cavity 10a and is fixed on a surface of the circuit board 13 facing the receiving cavity 10a, and the fixing manner may be glue connection, welding, or the like. It will be appreciated that the MEMS chip 20 may be configured in a corresponding manner depending on the particular type of MEMS sensor 100, such as a MEMS microphone, MEMS gas sensor, MEMS air pressure sensor, etc.

In this embodiment, the MEMS sensor 100 is a MEMS microphone. Accordingly, the MEMS chip 20 includes a substrate having a substantially cylindrical structure with both ends open, and a diaphragm, and the axis of the substrate is perpendicular to the circuit board 13. And, one end (lower end) of the substrate facing the circuit board 13 is fixed to a surface of the circuit board 13 facing the housing chamber 10a, and a diaphragm is provided in one end (upper end) of the substrate facing away from the circuit board 13. At this time, the vent holes 10b of the external package structure 10 are opened on the circuit board 13, and the cylindrical structure of the MEMS chip 20 surrounds the periphery of the vent holes 10b. In this way, communication between the MEMS chip 20 and the vent 10b is achieved, so that the MEMS chip 20 can detect external parameters (e.g., sound, gas, air pressure, etc.) through the vent 10b.

In this embodiment, the outside of the ventilation hole 10b is covered with the waterproof and breathable film 30, and the dual functions of waterproof and breathable of the waterproof and breathable film 30 not only do not affect the detection of external parameters (such as sound, gas, air pressure, etc.) by the MEMS chip 20 through the ventilation hole 10b, but also can play a role in preventing external moisture from entering the ventilation hole 10b, thereby ensuring that the components inside the MEMS sensor 100 are not damaged and can operate normally.

Further, in the present embodiment, a heating module 40 is further installed in the ventilation hole 10b, and the heating module 40 occupies only part of the ventilation channel of the ventilation hole 10b; therefore, the MEMS chip 20 is not affected to detect external parameters (e.g., sound, gas, air pressure, etc.) through the vent 10b. Meanwhile, due to the heat generating function of the heat generating module 40, heat can be directly emitted to the waterproof and breathable film 30, so that evaporation of a water film covering the waterproof and breathable film 30 is accelerated, and the MEMS sensor 100 can be quickly recovered after wading.

Furthermore, it can be appreciated that the heat generating module 40 can also support the waterproof and breathable film 30, thereby enhancing the waterproof pressure level of the waterproof and breathable film 30. Here, there are two cases:

first, the condition that the heat generating module 40 is in contact with the waterproof breathable film 30; at this time, the heat generating module 40 directly plays a supporting role;

second, the heating module 40 is spaced apart from the waterproof and breathable film 30 by a certain distance; at this time, the heating module 40 plays a supporting role when the waterproof breathable film 30 is deformed to some extent; in practical applications, the distance between the heating module 40 and the waterproof and breathable film 30 is determined by the deformability of the waterproof and breathable film 30, so long as the support is provided within the maximum elastic deformation range of the waterproof and breathable film 30, for example: the distance between the heat generating module 40 and the waterproof and breathable film 30 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm or 1mm.

In addition, in this embodiment, the MEMS sensor 100 further includes an ASIC chip, and the ASIC chip is also disposed in the accommodating cavity 10a and is also fixed on the surface of the circuit board 13 facing the accommodating cavity 10a, where the fixing manner may be glue connection, welding, or the like. The ASIC chip and the MEMS chip 20 are disposed at intervals, and can be electrically connected with each other through wires or through a circuit layer in the circuit board 13. Those skilled in the art can make reasonable selections according to the needs of the actual application scenario, and the method is not limited herein. It will be appreciated that, after the ASIC chip is mounted, the electrical signal converted by the MEMS chip 20 may be transferred to the ASIC chip, processed by the ASIC chip, and finally transferred to the outside.

The housing 11 is generally made of metal, so as to play a role of electromagnetic shielding, thereby reducing the possibility that the working performance of components (such as the MEMS chip 20, the ASIC chip, etc.) in the external packaging structure 10 is affected by the outside.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, the heat generating module 40 is a heat transfer element, the MEMS sensor 100 further includes an internal heat generating element 50, the internal heat generating element 50 is disposed in the accommodating cavity 10a, a first heat conducting track 131 is disposed in the external packaging structure 10, and one end of the first heat conducting track 131 is in contact with the internal heat generating element 50, and the other end is in contact with the heat transfer element.

It will be appreciated that the heat transfer element may be a structural member made of a metallic material (e.g. copper or aluminium), a structural member made of an alloy material (e.g. copper alloy or aluminium alloy), or a structural member formed by curing a thermally conductive glue (e.g. thermally conductive silicone). The first heat conductive track 131 may be made of metal (such as copper or aluminum), or may be made of alloy (such as copper alloy or aluminum alloy), or may be directly formed by curing a heat conductive adhesive.

The end of the first heat conductive track 131 contacting the internal heating element 50 may be fixed to the surface of the internal heating element 50 by heat conductive adhesive, or may be fixed to the surface of the internal heating element 50 by welding to contact the internal heating element 50. Similarly, the end of the first heat conducting track 131 contacting the heat transfer element may be fixed to the surface of the heat transfer element by bonding with a heat conducting adhesive, or may be fixed to the surface of the heat transfer element by welding. Therefore, the contact thermal resistance can be greatly reduced, thereby being beneficial to improving the heat transfer efficiency and reducing the heat loss; furthermore, the stability of the connection is improved, and the heat transfer process is more stable. Of course, the so-called "contact" may also take the form of a direct abutment or other effective and reasonable form.

At this time, the heat generated when the internal heating element 50 of the MEMS sensor 100 is operated is transferred to the heat transfer member through the first heat conductive rail 131, and then the heat is emitted to the waterproof and breathable film 30 through the heat transfer member, thereby accelerating evaporation of the water film covering the waterproof and breathable film 30.

In addition, in the present embodiment, the internal heating element 50 is an ASIC chip. Of course, in other embodiments, the internal heating element 50 may be other auxiliary devices, such as capacitors, resistors, other functional chips, etc., packaged within the external packaging structure 10.

In addition, as shown in fig. 2, in an embodiment, the heat transfer member may have a cross-shaped structure, four ends of which are supported on the inner wall of the ventilation hole 10b to achieve fixation of the heat transfer member.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, the external packaging structure 10 includes a circuit board 13, the ventilation holes 10b are opened on the circuit board 13, and the first heat conducting track 131 is disposed in the circuit board 13.

In this embodiment, the ventilation holes 10b, the waterproof and breathable film 30, the heat transfer element, and the first heat conduction track 131 are all integrated on the circuit board 13 of the external packaging structure 10.

In this way, the circuit board 13 is used as a carrier to realize integration, so that the number of independent parts in the subsequent packaging process can be effectively reduced, the packaging process is simplified, the packaging process is convenient to carry out, and the production efficiency of packaging and preparing the MEMS sensor 100 is improved; and the probability of error occurrence in the packaging process can be effectively reduced, and the product yield is improved.

In addition, since the internal heating element 50 of the MEMS sensor 100 is generally fixed on the circuit board 13, the technical solution of this embodiment can also greatly reduce the difficulty in contacting the first heat conducting track 131 with the internal heating element 50, thereby greatly reducing the difficulty in manufacturing the MEMS sensor 100 and improving the reliability and yield of the MEMS sensor 100.

Of course, in other embodiments, the ventilation holes 10b, the waterproof and breathable film 30, the heat transfer element, and the first heat conduction track 131 may be integrated on the housing 11 of the external packaging structure 10.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, the inner wall of the air vent 10b is provided with a heat conducting cylinder 133 disposed around, the heat transfer element is disposed in the heat conducting cylinder 133 and contacts the inner wall of the heat conducting cylinder 133, and the end of the first heat conducting track 131 away from the internal heating element 50 contacts the heat conducting cylinder 133.

It is understood that the heat conductive cylinder 133 may be a cylinder structure made of a metal material (e.g., copper or aluminum), a cylinder structure made of an alloy material (e.g., copper alloy or aluminum alloy), or a cylinder structure formed by curing a heat conductive paste (e.g., heat conductive silicone).

The end of the first heat conduction track 131 far away from the internal heating element 50 may be fixed to the outer side wall of the heat conduction cylinder 133 by heat conduction glue, or may be fixed to the outer side wall of the heat conduction cylinder 133 by welding to achieve contact with the heat conduction cylinder 133. Meanwhile, the contact mode of the heat transfer element and the inner wall of the heat conduction barrel 133 can be either a mode of bonding heat conduction glue or a welding mode. Therefore, the contact thermal resistance can be greatly reduced, thereby being beneficial to improving the heat transfer efficiency and reducing the heat loss; furthermore, the stability of the connection is improved, and the heat transfer process is more stable. Of course, the so-called "contact" may also take the form of a direct abutment or other effective and reasonable form.

At this time, the end of the first heat conductive rail 131 remote from the internal heating element 50 is brought into contact with the heat transfer member through the heat conductive cylinder 133. Thus, the heat transferred from the first heat conducting track 131 can be uniformly distributed in the heat conducting barrel 133, which is equivalent to forming a baking space around the heat transfer element; at this time, the heat transfer member is located in the "baking space", heat absorption is faster, and heat dissipation to the waterproof breathable film 30 is also more efficient. Also, the formation of the "baking space" means that the heat conductive cylinder 133 can directly heat the air inside thereof, thereby transferring heat to the waterproof and breathable film 30 through the air to further accelerate evaporation of the water film covering the waterproof and breathable film 30.

In an embodiment of the MEMS sensor 100 of the present invention, in order to further increase the heat absorption efficiency of the heat transfer element by the heat conductive cylinder 133, the heat dissipation efficiency of the heat transfer element to the waterproof and breathable film 30 is increased, so as to further accelerate the evaporation of the water film covering the waterproof and breathable film 30, the following optimization is performed on the heat transfer element:

the outer edge of the heat transfer element is circumferentially arranged along the heat conducting cylinder 133 and contacts the inner wall of the heat conducting cylinder 133.

Specifically, as shown in fig. 3, in an embodiment, the heat transfer element may be a plate-shaped structure with a plurality of hollow parts, and the outer contour shape of the plate-shaped structure matches the inner contour shape of the cross section of the heat conducting cylinder 133; thus, the outer edge of the plate-like structure may be disposed around the inner wall of the heat conductive cylinder 133 and in contact with the inner wall of the heat conductive cylinder 133. Also, as shown in fig. 2, in an embodiment, the heat transfer member may have a cross-shaped structure, four ends of which are supported on the inner wall of the heat conductive cylinder 133 and contact the inner wall of the heat conductive cylinder 133.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, a second heat conducting track 135 is further disposed in the external packaging structure 10, and one end of the second heat conducting track 135 is in contact with the heat transfer element, and the other end is exposed to the external surface of the external packaging structure 10 for contacting with an external heating element.

It is understood that the second heat conductive track 135 may be made of a metal material (such as copper or aluminum), an alloy material (such as copper alloy or aluminum alloy), or may be directly formed by curing a heat conductive glue. The end of the second heat conductive track 135 contacting the heat transfer member may be fixed to the surface of the heat transfer member by means of heat conductive adhesive, or may be fixed to the surface of the heat transfer member by means of welding. Therefore, the contact thermal resistance can be greatly reduced, thereby being beneficial to improving the heat transfer efficiency and reducing the heat loss; furthermore, the stability of the connection is improved, and the heat transfer process is more stable. Of course, the so-called "contact" may also take the form of a direct abutment or other effective and reasonable form.

At this time, after the MEMS sensor 100 is mounted to the corresponding position inside the electronic device, heat generated when the external heating element independent of the MEMS sensor 100 is operated is transferred to the heat transfer member, and then the heat is emitted to the waterproof and breathable film 30 via the heat transfer member, thereby further accelerating evaporation of the water film covering the waterproof and breathable film 30.

Further, it is understood that the external heating element may be other elements within the electronic device that are independent of the MEMS sensor 100, such as a central processor, a graphics processor, a display screen, a battery, other sensors, capacitance, resistance, and the like. When the heat conductive cylinder 133 is disposed in the ventilation hole 10b, the end of the second heat conductive rail 135 that contacts the heat transfer member may be in contact with the heat transfer member through the heat conductive cylinder 133, specifically: one end of the second heat conductive rail 135 contacting the heat transfer member is fixed to the outer side wall of the heat conductive cylinder 133 by means of heat conductive adhesive to contact the heat conductive cylinder 133, or fixed to the outer side wall of the heat conductive cylinder 133 by means of welding to contact the heat conductive cylinder 133, thereby achieving contact with the heat transfer member through the heat conductive cylinder 133.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, in order to facilitate the contact between the external heating element and the end of the second heat conduction track 135 away from the heat transfer element, and in order to avoid the encroachment of the front and back surface areas of the circuit board 13 by the end of the second heat conduction track 135 away from the heat transfer element, in order to facilitate the miniaturization of the MEMS sensor 100, the following optimization is performed on the exposed position of the end of the second heat conduction track 135 away from the heat transfer element on the outer surface of the external packaging structure 10:

the external packaging structure 10 includes a circuit board 13, and an end of the second heat conduction track 135 away from the heat transfer element is exposed from a side wall of the circuit board 13.

In practice, the external heating element may transfer heat to the end of the second heat conductive track 135 remote from the heat transfer element through an external heat conductive member (e.g., a metal member, an alloy member, etc.), thereby transferring heat to the heat transfer element through the second heat conductive track 135.

Furthermore, it will be appreciated that, in addition to the aforementioned implementation of the heat generating module 40 in the form of a heat transfer element to collect heat elsewhere at the vent 10b and thereby heat the waterproof breathable membrane 30, in an embodiment of the MEMS sensor 100 of the present invention, the heat generating module 40 may be configured in other forms: the heat generating module 40 is a self-heating element, and the external packaging structure 10 includes a circuit board 13, and the self-heating element is electrically connected to the circuit board 13.

Specifically, the self-heating element can be a resistor with a special shape (in order not to occupy all ventilation channels of the ventilation holes 10 b), a structure of a lower bracket and an upper conductive film, or a structure of a heating wire.

At this time, only the self-heating element is connected to the circuit layer of the circuit board 13, so that the self-heating element is also turned on to generate heat when the circuit board 13 is electrified, thereby radiating heat to the waterproof breathable film 30, accelerating the evaporation of the water film covered on the waterproof breathable film 30, and further enabling the MEMS sensor 100 to be quickly recovered after wading.

As shown in fig. 1, in an embodiment of the MEMS sensor 100 of the present invention, an adhesive layer 60 is disposed between the waterproof and breathable film 30 and the external packaging structure 10, and the waterproof and breathable film 30 is adhered to the external surface of the external packaging structure 10 through the adhesive layer 60.

In this embodiment, the ventilation holes 10b are provided on the circuit board 13; therefore, the waterproof breathable film 30 is adhered to the surface of the circuit board 13 facing away from the housing 11 through the adhesive layer 60, and covers the breathable holes 10b. Of course, in other embodiments, if the ventilation hole 10b is provided on the casing 11, the waterproof ventilation film 30 may be adhered to the surface of the casing 11 facing away from the storage cavity 10a by the adhesive layer 60, and cover the ventilation hole 10b.

As can be appreciated, the waterproof breathable film 30 is adhered and fixed by the adhesive layer 60, so that the operation is simple and the stability is good; and depending on the thickness of the adhesive layer 60, the waterproof and breathable film 30 and the heating module 40 can be separated by a certain distance, so as to meet the requirement of the MEMS microphone on the vibration of the waterproof and breathable film 30; meanwhile, the thickness of the bonding layer 60 is not too large, so that the waterproof breathable film 30 is prevented from being pulled to a position far away from the heating module 40, and the supporting effect of the heating module 40 in the ventilation holes 10b on the waterproof breathable film 30 is guaranteed.

In addition, in one embodiment, the adhesive layer 60 may be a pressure sensitive adhesive.

The invention also proposes an electronic device comprising a MEMS sensor 100 as described above, the specific structure of the MEMS sensor 100 being referred to the previous embodiments. Because the electronic device adopts all the technical schemes of all the embodiments, the electronic device at least has all the beneficial effects brought by all the technical schemes of all the embodiments, and the detailed description is omitted.

It is understood that the electronic device may be a cell phone, a notebook computer, a tablet computer, a personal digital assistant (Personal Digital Assistant, PDA), an electronic book reader, an MP3 (moving picture experts compression standard audio layer 3,Moving Picture Experts Group Audio Layer III) player, an MP4 (moving picture experts compression standard audio layer 4,Moving Picture Experts Group Audio Layer IV) player, a wearable device, a navigator, a palm game machine, etc.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the invention, and all equivalent structural changes made by the description of the present invention and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the invention.

Claims

1. A MEMS sensor, comprising:

the heating module is arranged in the ventilation holes and occupies only part of ventilation channels of the ventilation holes;

the MEMS sensor further comprises an internal heating element, wherein the internal heating element is arranged in the accommodating cavity, a first heat conduction track is arranged in the external packaging structure, one end of the first heat conduction track is in contact with the internal heating element, and the other end of the first heat conduction track is in contact with the heat transfer element;

the inner wall of the air vent is provided with a heat conduction cylinder body which is arranged in a surrounding manner, the heat transfer element is arranged in the heat conduction cylinder body and is in contact with the inner wall of the heat conduction cylinder body, and one end, far away from the internal heating element, of the first heat conduction track is in contact with the heat conduction cylinder body;

the external packaging structure is also provided with a second heat conduction track, one end of the second heat conduction track is contacted with the heat transfer element, and the other end of the second heat conduction track is exposed on the outer surface of the external packaging structure and is used for being contacted with an external heating element.

2. The MEMS sensor of claim 1, wherein the external packaging structure comprises a circuit board, the vent is open to the circuit board, and the first thermally conductive track is disposed in the circuit board.

3. The MEMS sensor of claim 1, wherein an outer edge of the heat transfer element is circumferentially disposed about the thermally conductive cylinder and in contact with an inner wall of the thermally conductive cylinder.

4. The MEMS sensor of claim 1, wherein the heat transfer element is in a plate-like structure having a plurality of spaced apart through holes.

5. The MEMS sensor of claim 1, wherein the heat generating module is a self-heating element, and the external packaging structure comprises a circuit board, the self-heating element being electrically connected to the circuit board.

6. The MEMS sensor according to any one of claims 1-5, wherein an adhesive layer is disposed between the waterproof breathable membrane and the outer packaging structure, the waterproof breathable membrane being adhered to an outer surface of the outer packaging structure by the adhesive layer.

7. An electronic device comprising a MEMS sensor as claimed in any one of claims 1 to 6.