TWI405508B - Circuit board - Google Patents

Abstract

A circuit board is provided. The circuit board includes a core layer, a first circuit layer, a second circuit layer, a metal layer and at least one conductive through hole. The core layer has a mesh structure and an opening formed therein. The opening extends from a side of the core layer to an opposite side of the core layer and exposes a portion of the mesh structure. The first circuit layer and the second circuit layer are disposed on two opposite sides of the core layer, respectively. The metal layer is disposed on the inner sidewall of the opening and on the mesh structure. The conductive through hole is disposed in the core layer to electrically connect the first circuit layer and the second circuit layer.

Description

circuit board

The present invention relates to a circuit board, and more particularly to a circuit board having an opening and having a metal mesh structure in the opening.

In recent years, with the rapid development of electronic technology, the high-tech electronics industry has come out one after another, making more humanized and better-functioning electronic products constantly innovating and designing towards light, thin, short and small trends. In these electronic products, a circuit board on which electronic components are mounted is usually disposed.

For a typical sensing device, a cover structure is usually provided on the circuit board. The cover structure defines a chamber with the circuit board, and the sensing element is located in the chamber. For example, in a microelectromechanical system (MEMS) microphone device, an acoustic wave sensing component (such as a MEMS wafer) is installed in a chamber and electrically connected to the circuit board. In addition, the circuit board has an opening to allow the chamber to communicate with the outside to allow the sensing element in the chamber to pass through the opening to sense the difference in air pressure between the acoustic wave or the chamber and the outside.

In order to prevent external pollutants from entering the chamber through the opening, causing the components in the chamber to be contaminated or even damaged, a mesh barrier is generally attached at the opening to block the pollutants from the outside. However, the attached mesh barriers are usually attached to the openings one by one in a manual or mechanical manner, which requires a lot of man-hours and high production costs, and does not ensure the yield of the product.

The present invention provides a wiring board having an opening and having a metal mesh structure in the opening.

The invention provides a circuit board comprising a core layer, a first circuit layer, a second circuit layer, a metal layer and at least one via hole. The core layer has a mesh structure and an opening, and the opening extends from one side of the core layer to the opposite side and exposes a portion of the mesh structure. The first circuit layer and the second circuit layer are respectively disposed on opposite sides of the core layer. The metal layer is disposed on the inner wall of the opening and the mesh structure. The via hole is disposed in the core layer to electrically connect the first circuit layer and the second circuit layer.

According to the circuit board of the embodiment of the invention, the material of the metal layer is, for example, copper, tin, nickel, gold or a combination thereof.

According to the circuit board of the embodiment of the invention, the mesh structure is, for example, a glass fiber layer.

According to the circuit board of the embodiment of the invention, the above-mentioned via hole penetrates the mesh structure, for example.

Based on the above, in the circuit board of the embodiment of the present invention, since the opening has a mesh structure, when the circuit board is applied to the sensing device, it is possible to prevent the contaminant from entering the chamber of the sensing device via the opening, thereby causing a feeling The measuring component is contaminated or damaged. In addition, since the opening has a metal mesh structure for blocking contaminants, there is no need to attach a barrier to the opening to block the contaminants, thereby achieving the purpose of shortening the working hours and reducing the cost, and effectively Ensure product yield. In addition, since the inner wall of the opening has a metal layer on the mesh structure, when the circuit board of the embodiment of the invention is applied to a sensing device that needs to shield electromagnetic interference, the sensing element in the sensing device can be prevented from being electromagnetically interfered. .

The above described features and advantages of the present invention will be more apparent from the following description.

1 is a cross-sectional view of a circuit board according to an embodiment of the invention. 2 is a top plan view of the opening surrounded by the circuit layer of FIG. 1. Referring to FIG. 1 and FIG. 2 simultaneously, the circuit board 100 includes a core layer 102, a first circuit layer 104, a second circuit layer 106, and via holes 108. The material of the core layer 102 is, for example, an insulating material. The core layer 102 has a mesh structure 110 therein. The mesh structure 110 is, for example, a fiberglass layer. Further, the core layer 102 has an opening 112. The opening 112 extends from one side of the core layer 102 to the opposite side and exposes a portion of the mesh structure 110. In the present embodiment, the opening 112 is a circular opening, but the invention is not limited thereto. In other embodiments, the opening 112 may also be an opening of other shapes, such as a square opening, depending on actual needs.

The first circuit layer 104 and the second circuit layer 106 are respectively disposed on opposite sides of the core layer 102. The first circuit layer 104 and the second circuit layer 106 are electrically connected by via holes 108 located in the core layer 102. The material of the first wiring layer 104, the second wiring layer 106 and the via holes 108 is, for example, a metal, which may be copper, tin, nickel, gold or a combination thereof. In the present embodiment, two via holes 108 are illustrated, but the present invention is not limited thereto. Further, the type of the via hole 108 is not limited to the type shown in FIG. 1, and may be various via holes commonly used in the art. In addition, in the present embodiment, a portion of the first wiring layer 104 surrounds one end of the opening 112, and a portion of the second wiring layer 106 surrounds the other end of the opening 112.

The metal layer 114 is disposed on the inner wall of the opening 112 and the mesh structure 110. The material of the metal layer 114 is, for example, copper, tin, nickel, gold or a combination thereof. In the present embodiment, the metal layer 114 on the inner wall of the opening 112 is connected to the first wiring layer 104 and the second wiring layer 106 surrounding the opening 112.

In the circuit board 100, since the mesh 112 is formed in the opening 112, it is possible to effectively prevent various contaminants from reaching the other side of the opening 112 through one side of the opening 112 through the opening 112 without additionally requiring an opening 112. Attach a barrier to block contaminants.

In addition, since the inner wall of the opening 112 and the mesh structure 110 have the metal layer 114, when the circuit board 100 is applied to the sensing device that needs to shield electromagnetic interference, the sensing element in the sensing device can be prevented from being electromagnetically disturbed.

In particular, in the present embodiment, the mesh structure 110 is entirely disposed in the core layer 102, and the via holes 108 extend through the mesh structure 110. In another embodiment, the mesh structure 110 may be disposed only in a portion of the core layer 102 and the via holes 108 may be disposed in other portions of the core layer 102. Alternatively, in another embodiment, the mesh structure 110 may be disposed only in a portion of the core layer 102 while the vias 108 extend through the mesh structure 110.

A sensing device having the wiring board 100 of the embodiment of the present invention will be described below.

3 is a cross-sectional view of a sensing device in accordance with an embodiment of the invention. Referring to FIG. 3 , the sensing device 300 includes a circuit board 100 , a cover structure 302 , and a sensing component 304 . The cover structure 302 is disposed on the circuit board 100 and defines a chamber 306 with the circuit board 100. The cover structure 302 can be electrically connected to the circuit board 100 by the second circuit layer 106, and a portion of the second circuit layer 106 can be located in the chamber 306. There may be other circuit structures in the cover structure 302. These circuit structures are not shown in this embodiment for clarity of illustration. In addition, the sensing component 304 is also disposed in the chamber 306 and can be electrically connected to the circuit board 100 by the second wiring layer 106 located in the chamber 306.

The sensing device 300 is, for example, a barometric sensing device or an acoustic wave sensing device, depending on the type of sensing element 304. When the sensing element 304 is a barometric sensing element, the sensing device 300 is a barometric sensing device. When the sensing element 304 is an acoustic wave sensing element, the sensing device 300 is an acoustic wave sensing device. For example, when the sensing element 304 is a MEMS wafer, the sensing device 300 is a MEMS microphone device that can be operated by the sensing element 304 sensing sound waves entering the chamber 306 through the opening 112.

In particular, since the opening 112 has a mesh structure 110 therein, it can effectively prevent various contaminants from entering the chamber 306 via the opening 112, preventing the sensing element 304 in the chamber 306 from being contaminated or damaged. For example, when the sensing device 300 is a MEMS microphone device, sound waves emitted by the user may enter the chamber 306 via the opening 112 to be sensed by the sensing element 304, and external dust or saliva of the user may be contaminants. Chamber 306 is also entered via opening 112. At this point, the mesh structure 110 can effectively isolate these contaminants from outside the chamber 306, preventing contamination or damage to the sensing elements 304 in the chamber 306.

In addition, when the sensing device 300 is a sensing device that needs to shield electromagnetic interference, since the inner wall of the opening 112 and the mesh structure 110 have the metal layer 114, the sensing element 304 can be effectively prevented from being electromagnetically interfered.

In addition, in another embodiment, the cover structure 302 may also have the same structure as the core layer 102, and thus the cover structure 302 may also have an opening similar to the opening 112.

In summary, in the circuit board of the embodiment of the present invention, since the opening has a mesh structure, it can effectively prevent various contaminants from reaching the other side of the opening through one side of the opening, so when the line When the board is applied to a sensing device that senses air pressure or sound waves, it is possible to prevent these contaminants from entering the chamber of the sensing device via the opening, causing the sensing element to be contaminated or damaged.

In addition, since the above-mentioned opening has a mesh structure for blocking contaminants, it is not necessary to attach a barrier to the opening to block the contaminant, thereby achieving the purpose of shortening the working time and reducing the cost, and effectively Improve product yield.

In addition, when the circuit board of the embodiment of the present invention is applied to a sensing device that needs to shield electromagnetic interference, since the inner wall of the opening and the mesh structure have a metal layer, the sensing element in the sensing device can be effectively prevented from being affected. Electromagnetic interference.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100. . . circuit board

102. . . Core layer

104. . . First circuit layer

106. . . Second circuit layer

108. . . Via

110. . . grid

112. . . Opening

114. . . Metal layer

300. . . Sensing device

302. . . Cover structure

304. . . Sensing element

306. . . Chamber

1 is a cross-sectional view of a circuit board according to an embodiment of the invention.

2 is a top plan view of the opening surrounded by the circuit layer of FIG. 1.

3 is a cross-sectional view of a sensing device in accordance with an embodiment of the invention.

100. . . circuit board

102. . . Core layer

104. . . First circuit layer

106. . . Second circuit layer

108. . . Via

110. . . grid

112. . . Opening

114. . . Metal layer

Claims (4)

A circuit board comprising: a core layer having a mesh structure and an opening therein, the opening extending from one side of the core layer to the opposite side, and exposing a portion of the mesh structure; a first circuit layer and a second circuit layer are respectively disposed on opposite sides of the core layer; a metal layer disposed on the inner wall of the opening and the mesh structure; and at least one via hole disposed in the In the core layer, the first circuit layer and the second circuit layer are electrically connected. The circuit board of claim 1, wherein the material of the metal layer comprises copper, tin, nickel, gold or a combination thereof. The circuit board of claim 1, wherein the mesh structure is a glass fiber layer. The circuit board of claim 1, wherein the through hole penetrates the mesh structure.