TWI403224B - Circuit board structure - Google Patents

Description

Board structure

The present invention relates to a circuit board structure, and more particularly to a circuit board structure for anti-static discharge interference.

In today's electronic devices, one or more printed circuit boards (PCBs) are often arranged. These printed circuit boards carry one or more electronic components (such as integrated circuits (ICs) and passive components). When the phenomenon of Electrostatic Discharge (ESD) occurs, these electronic components are often affected by the sudden high current generated by the electrostatic discharge, causing the system to crash or even permanently damage.

The above electrostatic discharge phenomenon can be roughly classified into a Human Body Model (HBM), a Mechanical Model (MM), and a Charged Device Model (CDM). In the technical field of the conventional electrostatic discharge protection, the countermeasure element is often added to the electrostatic discharge path that may occur according to different modes to divert the energy generated when the electrostatic discharge is performed. These countermeasure components are usually expensive, resulting in a substantial increase in the manufacturing cost of the product. In addition, there is also a circuit that uses a circuit that adds a tip discharge to the electrostatic discharge path to discharge the energy generated by the electrostatic discharge. This tip discharge circuit is placed on each of the possible electrostatic discharge paths, which increases the board area and also imposes a manufacturing cost burden.

The present invention provides two circuit board structures for reducing interference caused by electrostatic discharge on the circuit board.

The invention provides a circuit board structure comprising a core layer, a first patterned metal layer and at least one electrostatic discharge protection structure. The core layer has first and second surfaces. The first patterned metal layer is disposed on the first surface of the core layer and has a plurality of electrical signal conducting lines. The electrostatic discharge protection structure is a metal structure including a first portion, a second portion, and a connecting portion. The first portion is disposed on the first surface of the core layer and structurally isolated from the electrical signal conducting line, wherein the first portion is disposed in at least one line segment of the at least one protected conductive line adjacent to the electrical signal conducting line, and The line segments are electrically coupled. The second part is disposed on the second surface of the core layer. The connecting portion is disposed between the first portion and the second portion for electrically connecting the first and second portions and causing the electrostatic discharge protection structure to assume a ring structure.

In an embodiment of the invention, the connecting portion includes a plurality of through holes disposed in the core layer for electrically connecting the first and second portions.

In an embodiment of the invention, the first portion and the second portion extend to the outside of the first and second surfaces, and the connecting portion is disposed outside the core layer and electrically connected to the first portion and the second portion .

In an embodiment of the invention, the second patterned metal layer is further disposed on the second surface of the core layer.

In an embodiment of the invention, the core layer further includes N metal layers and N+1 dielectric layers. N metal layers are respectively disposed between N+1 dielectric layers, where N is a positive integer.

The invention provides a circuit board structure comprising a circuit substrate and at least one electrostatic discharge protection structure. The circuit substrate has a first surface and a second surface, and at least one of the first and second surfaces of the circuit substrate has a plurality of electrical signal conducting lines. The electrostatic discharge protection structure is a metal structure and is disposed on a side of the circuit substrate. The electrostatic discharge protection structure includes a first portion, a second portion, and a connecting portion. The first portion is disposed on the first surface of the core layer and is structurally isolated from the electrical signal conducting lines. The second portion is disposed on the second surface of the core layer. The connecting portion is disposed between the first portion and the second portion for electrically connecting the first and second portions and causing the electrostatic discharge protection structure to assume a ring structure.

In an embodiment of the invention, the circuit substrate is formed by stacking at least one dielectric layer and at least one metal layer, and at least one dielectric layer is between any two adjacent metal layers.

In an embodiment of the invention, the electrostatic discharge protection structure is electrically connected to the ground.

In an embodiment of the invention, the electrostatic discharge protection structure described above is physically isolated from the ground and the power source.

Based on the above, the present invention utilizes a ring-shaped electrostatic discharge protection structure disposed adjacent to an electrical signal conducting line such that an electrical signal conducting line and an electrostatic discharge protection structure are electrically coupled when an electrostatic discharge phenomenon occurs, thereby suppressing static electricity. The interference caused by the discharge phenomenon achieves the purpose of protecting the circuit components on the circuit board structure.

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

Please refer to FIG. 1 first. FIG. 1 is a schematic diagram of a circuit board structure 100 according to an embodiment of the present invention. The circuit board structure 100 includes a core layer 110, a patterned metal layer disposed on the first surface 111 of the core layer 110, and an electrostatic discharge protection structure 130. The core layer 110 further has a second surface 112. The patterned metal layer on the first surface 111 then has a plurality of electrical signal conducting lines 171, 172, wherein the protected conductive lines are, for example, electrical signal conducting lines 171. The ESD protection structure 130 is a metal structure including a first portion 131, a second portion 132, and a connection portion 133. In the present embodiment, the electrostatic discharge protection structure 130 is provided to reduce the interference of the electrostatic discharge of the protected electrical signal conducting line 171. Therefore, the electrostatic discharge protection structure 130 is disposed adjacent to the line segment LA in the protected electrical signal conducting line 171. Also, the ESD protection structure 130 can be electrically coupled to the line segment LA in the protected electrical signal conducting line 171.

It is further illustrated that the first portion 131 of the electrostatic discharge protection structure 130 is disposed on the first surface 111 of the core layer 110 and is structurally isolated from all of the electrical signal conducting lines 171, 172 on the first surface 111 of the core layer 110. . Also, the first portion 131 of the electrostatic discharge protection structure 130 is disposed adjacent to the line segment LA in the protected electrical signal conducting line 171 at a position sufficient to produce an electrical coupling distance. The second portion 132 of the ESD protection structure 130 is disposed on the second surface 112 of the core layer 110. The connecting portion 133 of the ESD protection structure 130 connects the first portion 131 and the second portion 132 of the ESD protection structure 130 to form the ESD protection structure 130 into a ring structure.

Here, the protected electrical signal conducting line 171 is connected to the circuit component 160 disposed on the first surface 111 of the core layer 110. The circuit component 160 therein may be an integrated circuit or a passive component. When the protected electrical signal conducting line 171 is subject to interference due to electrostatic discharge, the electrostatic discharge protection structure 130 will generate a corresponding magnetic field due to electrical coupling with the line segment LA. The magnetic field generated by this electrical coupling will effectively suppress the interference caused by the electrostatic discharge on the protected electrical signal conducting line 171, thereby suppressing the damage and interference to the circuit component 160 caused by the electrostatic discharge.

In this embodiment, the first portion 131 and the second portion 132 of the electrostatic discharge protection structure 130 respectively extend from the first surface 111 and the second surface 112 of the core layer 110, and the connection portion 133 is outside the core layer 110. The first portion 131 and the second portion 132 of the electrostatic discharge protection structure 130 are connected to each other.

Moreover, since the electrostatic discharge protection structure 130 is a metal ring structure, the magnetic field of the induced current generated by the electrostatic discharge coupling in the electrostatic discharge protection structure 130 is opposite to the magnetic field generated by the electrostatic discharge current, thereby canceling each other, thereby reducing the The interference of the protected electrical signal conducting line 171. That is to say, the electrostatic discharge protection structure 130 does not require an electrostatic discharge protection structure as in the prior art to introduce the energy generated by the electrostatic discharge into the ground or the power source. Furthermore, the electrostatic discharge protection structure 130 in this embodiment does not need to be connected to the ground or the power source, but can be physically isolated from the ground and the power source.

Incidentally, the electrostatic discharge protection structure 130 in the circuit board structure 100 of the present embodiment may be an external annular metal ring and used to cover the circuit board structure 100 at an appropriate position to form the electrostatic discharge protection structure 130. The circuit board structure 100 can also include another patterned metal layer disposed on the second surface 112 of the core layer 110. The patterned metal layer on the second surface 112 of the core layer 110 may also have a plurality of electrical signal conducting lines, and the electrostatic discharge protection structure 130 is structurally isolated from the electrical signal conducting lines.

In addition, please note that the circuit board structure 100 can also be a multi-layer board structure, wherein the core layer 110 can further include N metal layers and N+1 dielectric layers, where N is a positive integer. N metal layers are respectively disposed between N+1 dielectric layers.

Next, please refer to FIG. 2. FIG. 2 is a schematic diagram of a circuit board structure 200 according to another embodiment of the present invention. The circuit board structure 200 includes a core layer 210, a patterned metal layer disposed on the first surface 211 of the core layer 210, and an electrostatic discharge protection structure 230. The core layer 210 further has a second surface 212. The patterned metal layer on the first surface 211 has a plurality of electrical signal conducting lines 271, 272, wherein the electrical signal conducting lines 271, 272 are coupled to the circuit component 260.

The first portion 231 and the second portion 232 included in the electrostatic discharge protection structure 230 of the present embodiment are disposed on the first surface 211 and the second surface 212 of the core layer 210, respectively. The first portion 231 and the second portion 232 of the electrostatic discharge protection structure 230 do not extend out of the first surface 211 and the second surface 212 of the core layer 210, but utilize the first and second surfaces 211, 212 of the core layer 210. The upper metal layer (patterned metal layer) is formed. The connecting portion 232 of the electrostatic discharge protection structure 230 is constructed by a plurality of through holes 233 formed in the core layer 210, thereby joining the electrostatic discharge protection structures 230 into a ring structure.

For a more detailed description of the hierarchical relationship of the circuit board structure 200 of the present invention, reference is made to FIG. 3, which is a cross-sectional view taken along line A-A of FIG. The electrical signal conducting line 271 and the first portion 231 of the electrostatic discharge protection structure 230 are formed by a patterned metal layer 291 on the first surface 211 of the core layer 210. The second portion 232 of the ESD protection structure 230 is formed by the patterned metal layer 292 on the second surface 212 of the core layer 210. The through hole 233 is disposed between the first and second surfaces 211 and 212 of the core layer 210, and connects the first portion 231 and the second portion 232 of the electrostatic discharge protection structure 230. Additionally, it is noted that the patterned metal layer 292 on the second surface 212 of the core layer 210 can also be used to form the electrical signal conducting lines 273.

Please refer to FIG. 4. FIG. 4 is a schematic diagram of a circuit board structure 400 according to still another embodiment of the present invention. In the depiction of FIG. 4, circuit board structure 400 includes more than one electrostatic discharge protection structures 430 and 450. The electrostatic discharge protection structure 430 is used to be disposed adjacent to the electrical signal conducting line 471, and the electrostatic discharge protection structure 450 is configured to be disposed adjacent to the electrical signal conducting line 472. That is, the corresponding electrostatic discharge protection structures 430, 450 can be disposed in the circuit board structure 400 for different electrical signal conducting lines 471, 472 to generate static discharges for the plurality of electrical signal conducting lines 471, 472. The interference is suppressed to increase the protection effectiveness of the electrostatic discharge.

5A and 5B, FIG. 5A and FIG. 5B are respectively schematic diagrams of a circuit board structure 500 according to a further embodiment of the present invention. In the depiction of FIG. 5A, the circuit board structure 500 includes a circuit substrate 570 and an electrostatic discharge protection structure 530. The circuit substrate 570 has a first surface 571 and a second surface 572, and at least one of the first and second surfaces 571, 572 of the circuit substrate 570 has a plurality of electrical signal conducting lines. The circuit board structure 500 includes at least one electrostatic discharge protection structure 530 which is a metal structure and is disposed on a side of the circuit substrate 570. In the present embodiment, two electrostatic discharge protection structures 530 are respectively disposed on the two long sides of the circuit substrate 570. The electrostatic discharge protection structure 530 also has a first portion 531, a second portion 532, and a connection portion 533, as in the previous embodiment. The first portion 531 and the second portion 532 extend from the first and second surfaces 571 and 572 of the circuit substrate 570 and are connected to each other by the connecting portion 533 to form the ESD protection structure 530 into a ring structure.

In addition, in the illustration of FIG. 5B, the electrostatic discharge protection structure 540 is formed by using a patterned metal layer on the circuit substrate 570, and is connected by a through hole to form the electrostatic discharge protection structure 540 into a ring structure.

It should be noted here that in the embodiment of FIGS. 5A and 5B, the circuit board structure 500 simply surrounds one side of the circuit substrate 570 with at least one electrostatic discharge protection structure 530 or 540, and thereby the electrostatic discharge protection structure The 530 or 540 is electrically coupled to a plurality of electrical transmission lines on the circuit substrate 570, and this electrical coupling phenomenon is utilized to suppress interference generated when electrostatic discharge occurs on the circuit board structure 500.

It is worth mentioning that the circuit substrate 570 is formed by staggering at least one dielectric layer and at least one metal layer, and at least one dielectric layer is located between any two adjacent metal layers.

In summary, the present invention utilizes an electrostatic discharge protection structure of a ring-shaped metal structure to be disposed at a suitable position in the circuit board structure to suppress interference phenomena generated in the circuit board structure when electrostatic discharge occurs, thereby protecting the circuit board. Circuit components in the structure are undisturbed or destroyed. The electrostatic discharge protection structure proposed by the invention can be formed by using an external metal ring or directly by using a patterned metal layer and a through hole in the circuit board structure, without expensive circuit components, and effectively reducing the cost of the product.

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, 200, 400, 500. . . Board structure

110, 210. . . Core layer

111, 112, 211, 212, 571, 572. . . surface

130, 230, 430, 450, 530, 540. . . Electrostatic discharge protection structure

131~133, 231~233, 531~533. . . Part of the ESD protection structure

171. . . Protected electrical signal transmission line

172, 271, 272, 273, 471, 472. . . Electrical signal transmission line

160, 260. . . Circuit component

291, 292. . . Patterned metal layer

570. . . Circuit substrate

LA. . . Line segment

1 is a schematic diagram of a circuit board structure 100 in accordance with an embodiment of the present invention.

2 is a schematic diagram of a circuit board structure 200 in accordance with another embodiment of the present invention.

Figure 3 is a schematic cross-sectional view taken along line A-A of Figure 2;

4 is a schematic diagram of a circuit board structure 400 in accordance with still another embodiment of the present invention.

5A and 5B are schematic views of a circuit board structure 500 according to a further embodiment of the present invention.

100. . . Board structure

110. . . Core layer

111, 112. . . surface

130. . . Electrostatic discharge protection structure

131, 132, 133. . . Part of the ESD protection structure

171. . . Protected electrical signal transmission line

172. . . Electrical signal transmission line

160. . . Circuit component

LA. . . Line segment

Claims (9)

A circuit board structure comprising: a core layer having a first surface and a second surface; a first patterned metal layer disposed on the first surface of the core layer and having a plurality of electrical signal conducting lines; And the at least one electrostatic discharge protection structure is a metal structure, including: a first portion disposed on the first surface of the core layer and structurally isolated from the electrical signal conducting lines, wherein the first portion is disposed at Adjacent to at least one line segment of the at least one protected conductive line of the electrical signal conducting lines and electrically coupled to the line segment; a second portion disposed on the second surface of the core layer; and a connection a portion disposed between the first portion and the second portion for electrically connecting the first and second portions and causing the electrostatic discharge protection structure to assume a ring structure, wherein the first portion and the second portion The portion extends to the outside of the first and second surfaces, and the connecting portion is disposed outside the core layer and electrically connected to the first and second portions. The circuit board structure of claim 1, further comprising: a second patterned metal layer disposed on the second surface of the core layer. The circuit board structure of claim 1, wherein the core layer further comprises: N metal layers and N+1 dielectric layers, wherein N is a positive integer, and each of the metal layers is disposed between each of the dielectric layers. The circuit board structure of claim 1, wherein the electrostatic discharge protection structure is electrically connected to a ground. The circuit board structure of claim 1, wherein the electrostatic discharge protection structure is physically isolated from a ground and a power source. A circuit board structure comprising: a circuit substrate having a first surface and a second surface, at least one of the first and second surfaces of the circuit substrate having a plurality of electrical signal conducting lines; and at least one static electricity The discharge protection structure is a metal structure disposed on one side of the circuit substrate, including: a first portion disposed on the first surface of the core layer and structurally isolated from the electrical signal conducting lines; a second portion disposed on the second surface of the core layer; and a connecting portion disposed between the first portion and the second portion for electrically connecting the first portion and the second portion and causing the static electricity The discharge protection structure has a ring structure, wherein the first portion and the second portion extend to the outside of the first and second surfaces, and the connection portion is disposed outside the circuit substrate and electrically connected to the first portion One and the second part. The circuit board structure of claim 6, wherein the circuit substrate is formed by stacking at least one dielectric layer and at least one metal layer. And at least one of the dielectric layers is between any two adjacent metal layers. The circuit board structure of claim 6, wherein the electrostatic discharge protection structure is electrically connected to a ground. The circuit board structure of claim 6, wherein the electrostatic discharge protection structure is physically isolated from a ground and a power source.