CN210053572U - A loudspeaker with package structure - Google Patents

Abstract

The present application discloses a loudspeaker with a package structure. The loudspeaker with a package structure has a MEMS loudspeaker and a transmitting circuit formed on a substrate at the same time, and realizes the connection between the MEMS loudspeaker and the transmitting circuit through interconnecting lines located on the surface of the substrate. The electrical connection avoids the problem that the volume of the MEMS speaker and the transmitting circuit is difficult to be further reduced due to the use of lead wires in the prior art, and the problem that the stray capacitance caused by too many leads adversely affects the normal operation of the MEMS speaker and the transmitting circuit.

Description

A loudspeaker with package structure

technical field

The present application relates to the technical field of acoustic equipment, and more particularly, to a loudspeaker with a package structure.

Background technique

Sound is produced by the vibration of an object, and we call the object that is taking place a sound source. The pressure wave generated by the vibration of the object moves through the air, and then vibrates the auditory ossicles of the inner ear. These vibrations are converted into tiny electronic brain waves by the auditory ossicles, so that people can perceive sound.

Loudspeaker, also known as horn, is a common electro-acoustic transducer. Its function is to convert electrical signals into sound signals, and transmit the sound signals to the outside world in the form of vibration to achieve sound transmission.

MEMS (Micro-Electro-Mechanical System) speakers have the advantages of low power consumption, small size, small size and good consistency, and are the development direction of the speaker field. How to further reduce the volume of MEMS speakers so that MEMS speakers can further adapt to the miniaturization needs of downstream products has become one of the research directions of researchers.

Utility model content

In order to solve the above technical problems, the present application provides a loudspeaker with a package structure, so as to further reduce the volume of the MEMS loudspeaker.

To achieve the above purpose, the application provides the following technical solutions:

A loudspeaker with a package structure, comprising:

a substrate including a first surface;

A transmitting circuit, a MEMS speaker and an interconnection line located on one side of the first surface; both the transmitting circuit and the MEMS speaker are electrically connected to the interconnection line.

Optionally, the transmitting circuit is electrically connected to the interconnecting circuit through a plurality of first pads;

The MEMS speaker is electrically connected to the interconnection line through a plurality of second pads.

Optionally, also include:

an acoustic hole through the substrate, and a cavity partially through the MEMS speaker;

The opening diameter of the cavity is larger than the opening diameter of the acoustic hole, and the cavity is located above the acoustic hole.

Optionally, the cross-sectional shape of the acoustic hole is circular.

Optionally, the diameter of the cross section of the acoustic hole ranges from 10 to 5000 μm;

The value range of the height of the acoustic hole is 100-1000 μm.

Optionally, the MEMS speaker includes a piezoelectric MEMS speaker.

Optionally, the piezoelectric MEMS speaker includes:

a base, the cavity penetrates the upper and lower surfaces of the base;

single or multiple stacked piezoelectric cells on one side of the upper surface of the substrate;

a mask layer on the lower surface of the substrate.

Optionally, the piezoelectric MEMS speaker further includes:

a vibrating dielectric film layer on one side of the upper surface of the substrate;

The single or multiple stacked piezoelectric units are located on the side of the vibrating dielectric film layer facing away from the substrate.

Optionally, the vibration medium film layer includes:

It is a single-layer or multi-layer vibration dielectric film layer composed of a silicon oxide layer, a silicon nitride layer, a silicon layer, and a polymer waterproof material.

Optionally, the piezoelectric unit includes:

a bottom electrode on one side of the upper surface of the substrate;

a piezoelectric layer on the side of the bottom electrode facing away from the substrate;

a top electrode on the side of the piezoelectric layer facing away from the substrate.

It can be seen from the above technical solutions that the present application provides a loudspeaker with a package structure, the loudspeaker with a package structure encapsulates the MEMS loudspeaker and the transmitting circuit together through the interconnection lines between the substrate and the surface of the substrate, avoiding the need for existing In the prior art, the electrical connection between the MEMS loudspeaker and the transmitting circuit is realized by structures such as lead wires, and the problem of large volume is caused, and the stray capacitance caused by the excessive lead wires in the prior art is avoided. adverse effects.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only It is an embodiment of the present application. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without any creative effort.

1 is a schematic structural diagram of a loudspeaker in the prior art;

FIG. 2 is a schematic structural diagram of a loudspeaker with a package structure provided by an embodiment of the present application;

3 is a schematic structural diagram of a loudspeaker with a package structure provided by another embodiment of the present application;

4 is a schematic structural diagram of a loudspeaker with a package structure provided by yet another embodiment of the application;

5 is a schematic structural diagram of a loudspeaker with a package structure provided by yet another embodiment of the present application;

6 is a schematic structural diagram of a loudspeaker with a package structure provided by an optional embodiment of the present application;

7 is a schematic structural diagram of a loudspeaker with a package structure provided by another optional embodiment of the present application;

8 is a schematic structural diagram of a MEMS speaker according to an embodiment of the present application;

9 is a schematic structural diagram of a MEMS speaker provided by another embodiment of the present application;

FIG. 10 is a schematic structural diagram of a MEMS speaker according to yet another embodiment of the present application.

Detailed ways

As described in the background art, referring to FIG. 1 , a MEMS speaker 1 in the prior art is electrically connected to a transmitting circuit 3 through a connection structure such as a lead 2 , wherein the transmitting circuit 3 is used to provide an electrical signal for the MEMS speaker 1 , and the electrical The signal drives the MEMS speaker 1 to vibrate, thereby emitting corresponding sound. The substrate 4 is also shown in FIG. 1 .

Too many leads not only make the overall structure of the system larger, but also the stray capacitance caused by too many leads will adversely affect the normal operation of the MEMS speaker and the transmitting circuit.

In view of this, embodiments of the present application provide a speaker with a package structure, including:

a substrate including a first surface;

A transmitting circuit, a MEMS speaker and an interconnection line located on one side of the first surface; both the transmitting circuit and the MEMS speaker are electrically connected to the interconnection line.

The loudspeaker with the package structure has a MEMS loudspeaker and a transmitting circuit formed on the substrate at the same time, and the electrical connection between the MEMS loudspeaker and the transmitting circuit is realized through the interconnection lines located on the surface of the substrate, avoiding the use of lead connection in the prior art. The problem that the volume of the MEMS speaker and the transmitting circuit is difficult to be further reduced, and the problem that the stray capacitance caused by too many leads has an adverse effect on the normal operation of the MEMS speaker and the transmitting circuit.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

Reference in this specification to an "embodiment" or similar terms means a characteristic, structure, or characteristic associated with the embodiment, which is included in at least one embodiment of the present application. Thus, appearances of the phrases "in an embodiment," "in an embodiment," and similar phrases in this specification may, but do not necessarily, all refer to the same embodiment.

Furthermore, the features, structures or characteristics described herein may be combined in any manner in one or more embodiments. The following description will provide numerous specific details to provide an understanding of embodiments of the present application. One of ordinary skill in the relevant art will recognize, however, that the present application may be practiced without one or more of the specific details, or with other methods, components, materials, and the like. In other instances, well-known structures, materials, or operations have not been described in detail to avoid obscuring the present application.

An embodiment of the present application provides a loudspeaker with a package structure, as shown in FIG. 2 , including:

a substrate 40, the substrate 40 including a first surface;

The transmitting circuit 20 , the MEMS speaker 10 and the interconnection line 30 located on one side of the first surface; the transmitting circuit 20 and the MEMS speaker 10 are all electrically connected to the interconnection line 30 .

In FIG. 2 , the substrate 11 of the MEMS speaker 10 is also shown, as well as the functional structure 12 of the MEMS speaker and the substrate 22 of the transmitting circuit 20 , and the functional structure 21 of the transmitting circuit 20 .

In this embodiment, for the speaker with the package structure, the MEMS speaker 10 and the transmitting circuit 20 are formed on the substrate 40 at the same time, and the MEMS speaker 10 and the transmitting circuit 20 are realized through the interconnecting lines 30 located on the surface of the substrate 40 . It avoids the difficulty of further reducing the volume caused by the use of wires to connect the MEMS speaker 10 and the transmitting circuit 20 in the prior art, and the stray capacitance caused by too many wires has an adverse effect on the normal operation of the MEMS speaker 10 and the transmitting circuit 20. The problem.

In this embodiment, the process of forming the interconnection line 30 on a substrate 40 and electrically connecting the transmitting circuit 20 and the MEMS speaker 10 together through the interconnection line 30 may be SIP (System In a Package) packaging craft.

In FIG. 2 , both the MEMS speaker 10 and the transmitting circuit 20 are front-mounted chips, that is, the functional structures of the MEMS speaker 10 and the transmitting circuit 20 are located on the side away from the substrate 40 , and these functional structures pass through through holes through their respective substrates. It is electrically connected to the interconnection lines 30 located on the surface of the substrate 40 .

Referring to FIG. 3 , FIG. 3 is another speaker with a package structure. In FIG. 3 , both the MEMS speaker 10 and the transmitting circuit 20 are flip chips, that is, the functional structures of the MEMS speaker 10 and the transmitting circuit 20 are located toward the substrate. On the side of 40, these functional structures are directly electrically connected to the transmitting circuit 20, thereby realizing electrical connection with each other.

The interconnecting lines 30 can be directly formed by thermal evaporation metal layers and photolithography processes to form circuit patterns that meet electrical connection requirements, and the interconnecting lines 30 can also be formed through other metal layer forming processes and pattern forming processes. This application does not limit this, depending on the actual situation.

The functional structure of the transmitting circuit 20 generally includes a voltage gain function and an impedance matching function.

Referring to FIG. 4 and FIG. 5 , FIG. 4 and FIG. 5 also show an external connection structure 41 located on the side of the substrate 40 away from the MEMS speaker 10 , and the external connection structure 41 may be an external pad or an external connection Solder ball and other structures. The external connection structure 41 is electrically connected to the interconnection line 30 through a through hole (not shown in the drawings) penetrating the substrate 40 , and further electrically connected to the MEMS speaker 10 and the transmitting circuit 20 . During use, other devices can be connected to the MEMS speaker 10 with the package structure through the external connection structure 41 .

Referring to FIG. 6, FIG. 6 shows that when the MEMS speaker 10 and the transmitting circuit 20 are both positive chips, the transmitting circuit 20 is electrically connected to the interconnecting line 30 through a plurality of first pads 13;

The MEMS speaker 10 is electrically connected to the interconnection line 30 through a plurality of second pads 23 .

Optionally, the first pads 13 and the second pads 23 may also be solder ball structures.

In the structure shown in FIG. 6 , the functional structures of the MEMS speaker 10 and the transmitting circuit 20 are electrically connected to the interconnection line 30 through the electrical connection with the first pad 13 and the second pad 23 respectively.

On the basis of the above-mentioned embodiment, in another embodiment of the present application, referring to FIG. 7 , the speaker with the package structure further includes:

Acoustic holes 14 penetrating the substrate, and partially penetrating the cavity 11' of the MEMS speaker;

The opening diameter of the cavity 11 ′ is larger than the opening diameter of the acoustic hole 14 , and the cavity 11 ′ is located above the acoustic hole 14 .

The function of the sound hole 14 is to adjust the frequency response characteristics of the MEMS speaker 10 . Specifically, the sound hole 14 and the cavity 11 ′ of the MEMS speaker 10 constitute a Helmholtz resonant cavity, and the size of the sound hole 14 can be adjusted. The frequency response of the MEMS speaker 10 is adjusted.

Optionally, the diameter of the cross section of the acoustic hole 14 ranges from 10 to 5000 μm;

The value range of the height of the acoustic hole 14 is 100-1000 μm.

Optionally, the cross-sectional shape of the acoustic hole 14 is circular.

Optionally, the MEMS speaker 10 includes a piezoelectric MEMS speaker.

On the basis of the above-mentioned embodiment, another embodiment of the present application provides a specific structure of a piezoelectric MEMS speaker. Referring to FIG. 8 , the piezoelectric MEMS speaker includes:

The base 11, the cavity 11' runs through the upper and lower surfaces of the base 11;

Single or multiple stacked piezoelectric units 12' on one side of the upper surface of the substrate 11;

The mask layer 15 on the lower surface of the substrate 11 .

9 and 10, the piezoelectric unit 12' includes:

a bottom electrode 121 located on one side of the upper surface of the substrate 11;

the piezoelectric layer 122 on the side of the bottom electrode 121 facing away from the substrate 11;

The top electrode 123 is located on the side of the piezoelectric layer 122 facing away from the substrate 11 .

10, the piezoelectric MEMS speaker further includes:

A vibrating dielectric film layer 16 on one side of the upper surface of the substrate;

The single or multiple stacked piezoelectric units 12' are located on the side of the vibrating dielectric film layer away from the substrate.

Optionally, the vibration medium film layer 16 includes:

The single-layer or multi-layer vibration dielectric film layer 16 is composed of a silicon oxide (SiO ₂ ) layer, a silicon nitride (SiN) layer, a silicon (Si) layer, a polymer waterproof material, and the like.

Correspondingly, an embodiment of the present application further provides a communication device, including the MEMS speaker with a package structure as described in any of the foregoing embodiments.

To sum up, the embodiments of the present application provide a speaker with a package structure, the speaker with a package structure encapsulates the MEMS speaker and the transmitting circuit together through the interconnection lines between the substrate and the surface of the substrate, avoiding the need for existing In the technology, the electrical connection between the MEMS speaker and the transmitting circuit is realized through the lead structure, and the problem of large volume is caused, and the stray capacitance caused by excessive leads in the prior art is avoided. influences.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, this application is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A loudspeaker with a package structure is characterized in that, comprising: a substrate including a first surface; A transmitting circuit, a MEMS speaker and an interconnection line located on one side of the first surface; both the transmitting circuit and the MEMS speaker are electrically connected to the interconnection line. 2. The loudspeaker with a package structure according to claim 1, wherein the transmitting circuit is electrically connected to the interconnecting circuit through a plurality of first pads; The MEMS speaker is electrically connected to the interconnection line through a plurality of second pads. 3. The loudspeaker with package structure according to claim 1, characterized in that, further comprising: an acoustic hole through the substrate, and a cavity partially through the MEMS speaker; The opening diameter of the cavity is larger than the opening diameter of the acoustic hole, and the cavity is located above the acoustic hole. 4 . The loudspeaker with a package structure according to claim 3 , wherein the cross-sectional shape of the sound hole is circular. 5 . 5 . The loudspeaker with a package structure according to claim 4 , wherein the diameter of the cross section of the sound hole ranges from 10 to 5000 μm; 6 . The value range of the height of the acoustic hole is 100-1000 μm. 6 . The loudspeaker with a package structure according to claim 3 , wherein the MEMS loudspeaker comprises a piezoelectric MEMS loudspeaker. 7 . 7. The loudspeaker with a package structure according to claim 6, wherein the piezoelectric MEMS loudspeaker comprises: a base, the cavity penetrates the upper and lower surfaces of the base; single or multiple stacked piezoelectric cells on one side of the upper surface of the substrate; a mask layer on the lower surface of the substrate. 8. The speaker with a package structure according to claim 7, wherein the piezoelectric MEMS speaker further comprises: a vibrating dielectric film layer on one side of the upper surface of the substrate; The single or multiple stacked piezoelectric units are located on the side of the vibrating dielectric film layer facing away from the substrate. 9. The loudspeaker with a package structure according to claim 8, wherein the vibration dielectric film layer comprises: It is a single-layer or multi-layer vibration dielectric film layer composed of a silicon oxide layer, a silicon nitride layer, a silicon layer, and a polymer waterproof material. 10. The speaker with a package structure according to claim 7, wherein the piezoelectric unit comprises: a bottom electrode on one side of the upper surface of the substrate; a piezoelectric layer on the side of the bottom electrode facing away from the substrate; a top electrode on the side of the piezoelectric layer facing away from the substrate.

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