TW202021430A - Circuit board structure - Google Patents

Abstract

A circuit board structure includes a printed circuit board. The printed circuit board includes a substrate, a conductive pattern and a protecting layer. The conductive pattern is on the substrate. The protecting layer covers the conductive pattern, and exposes a portion of the conductive pattern used as an optical positioning mark having a ring shape.

Description

Circuit board structure

The invention relates to a circuit board structure, and in particular to a circuit board structure including a printed circuit board.

Printed circuit boards are commonly used substrates for electronic components. It is often necessary to install many electronic components on a printed circuit board. At present, electronic devices have been commonly used to assemble electronic components to printed circuit boards. Among them, positioning marks can be provided on the printed circuit board, and during the assembly of the electronic component, the orientation of the positioning mark is detected by an optical detection device, thereby understanding the relative relationship between the electronic component and the printed circuit board.

The invention relates to a circuit board structure, which can have better product yield.

According to one aspect of the invention, a circuit board structure is proposed, including a printed circuit board. The printed circuit board includes a substrate, a conductive pattern and a protective layer. The conductive pattern is on the substrate. The protective layer covers the conductive pattern, and exposes part of the conductive pattern as a positioning mark. The positioning mark has a ring shape.

In order to have a better understanding of the above and other aspects of the present invention, the following specific examples and the accompanying drawings are described in detail as follows:

The following is an example for detailed description. The example is only used as an example and is not intended to limit the scope of the present invention. The following description uses the same/similar symbols to indicate the same/similar components.

FIG. 1 is a schematic top view of a circuit board structure according to an embodiment of the present invention. Figure 2 is a cross-sectional view of the circuit board structure of Figure 1 drawn along line AB.

Please refer to FIGS. 1 and 2, the circuit board structure includes a printed circuit board 102. The printed circuit board 102 includes a substrate 104, a conductive pattern 106, and a protective layer 108. The substrate 104 may include a conductive layer 110 and an insulating layer 112. The insulating layer 112 is disposed on the conductive layer 110. The conductive pattern 106 may be disposed on the insulating layer 112 of the substrate 104. The protective layer 108 may cover the conductive pattern 106 and the substrate 104. In this embodiment, the conductive layer 110 is a copper foil layer.

In the embodiment, the conductive pattern 106 is partially covered by the protective layer 108, and the conductive pattern 106 includes a positioning mark 106M to expose the protective layer 108. As shown in FIG. 1, the portion of the conductive pattern 106 exposed by the protective layer 108 is marked with solid diagonal lines, and the portion covered by the protective layer 108 is marked with imaginary dots. In the embodiment, the protective layer 108 defines an opening 108K. The portion where the conductive pattern 106 exposes the opening 108K is the positioning mark 106M, and defines an aperture 106K, which can expose the insulating layer 112 of the substrate 104. The outline of the positioning mark 106M can be defined by the aperture 106K of the conductive pattern 106 and the opening 108K of the protective layer 108. In the embodiment, the positioning mark 106M has a ring shape, and the hollow portion is the aperture 106K. The opening 108K of the protective layer 108 defines a ring-shaped outer edge of the positioning mark 106M. In this embodiment, the positioning mark 106M is an optical positioning point.

In the embodiment shown in FIG. 1, the positioning mark 106M has a regular ring shape, which can clearly distinguish common circuit components, such as conductive lines, contact pads, solder contact points, etc., thereby providing accurate and quickly distinguishable Positioning information can improve production energy efficiency and product yield. In one embodiment, the diameter of the inner circular edge of the regular ring shape of the positioning mark 106M is 1 mm, and the diameter of the outer circular edge is 3 mm. However, the present disclosure is not limited to this. The ring shape of the positioning mark 106M may include other types of ring shapes, such as an oval ring shape and the like, or a polygonal ring shape such as a triangular ring shape, a quadrangular ring shape, a pentagonal ring shape, etc. Or other suitable shapes, such as the outer edge and the inner edge of the ring shape may have different shape contours, for example, the outer edge is a ring-shaped edge, and the inner edge is a polygonal edge.

The conductive pattern 106 with the positioning mark 106M can be electrically connected to a ground terminal, so that during the positioning process, whether other adjacent components (such as other electronic components electrically isolated from the conductive pattern 106) are positively or negatively charged The potential difference between the conductive pattern 106 and other components is small. Therefore, it can avoid the situation that the high-voltage flashover of the positioning mark 106M during the positioning process causes the damage of the electronic component 216, and improve the product yield. For example, referring to FIG. 1, the protective layer 108 may further have a through hole 108T, and the portion of the conductive pattern 106 exposing the through hole 108T may serve as a conductive contact 106C. In one embodiment, solder can be used to connect one end of the line 214 to the conductive contact 106C, and the other end is electrically connected to the ground.

The electronic component 216 can be disposed on the protective layer 108 and electrically connected to the conductive pattern 106 with the positioning mark 106M, so that the electronic component 216 and the conductive pattern 106 with the positioning mark 106M can have the same electrical properties, for example, both have positive electrical properties Therefore, the potential difference between the two is small, which can avoid the situation that the high-voltage flashover of the positioning mark 106M during the positioning process causes the damage of the electronic component 216, and improve the product yield.

In one embodiment, the conductive pattern 106 and the electronic component 216 which are electrically connected to each other can be electrically connected to a ground, so the potential difference between the conductive pattern 106 with the positioning mark 106M and the electronic component 216 is small, that is, the potential difference can approach Zero, thereby avoiding the situation in which the high-voltage flashover of the positioning mark 106M during the positioning process causes damage to the electronic component 216 and improves the product yield. In one embodiment, the electrode contact of the electronic component 216 can be connected to the conductive contact 106C by using solder, for example, and the electrical connection to the ground terminal is provided through the external contact pad component of the electronic component 216.

The material of the conductive pattern 106 and the conductive layer 110 may include metal. In one embodiment, the printed circuit board 102 includes a metal-core printed circuit board (Metal-Core Printed Circuit Board; MCPCB). The conductive layer 110 may include an aluminum plate. The insulating layer 112 may include polypropylene (PP). The conductive patterns 106 may include copper patterns to provide electrical wiring and connections. The protective layer 108 may have electrical insulation properties. In one embodiment, the protective layer 108 is a solder mask, and the material includes, for example, white paint. However, the disclosure is not limited thereto, and the printed circuit board 102 may also include other types of printed circuit boards.

The electronic component 216 includes a light emitting device, a passive component device, or an integrated electronic component. The light emitting device includes, for example, a light emitting diode light emitting unit, a light emitting diode packaging structure, and the like. Passive component devices include, for example, resistors, capacitors, inductors, and the like. Integrated electronic components include, for example, driving integrated circuits and the like.

In one embodiment, the printed circuit board 102 has a device area for receiving and assembling electronic components 216, and the positioning mark 106M is disposed outside the device area. In the process of assembling the electronic component 216 using the automatic placement machine, the orientation of the positioning mark 106M of the printed circuit board 102 is detected by an optical inspection device, thereby controlling the electronic component 216 to be accurately assembled to the surface of the printed circuit board 102 In the device area. In one embodiment, the electronic component 216 can be assembled onto the solder pads on the printed circuit board 102 using surface-mount technology (SMT).

In a comparative example, the positioning mark is formed by the entire conductive pattern exposed by the protective layer 108, and has a solid circular shape with a diameter of about 1 mm from the top view, and is floating. During the assembly of the electronic component 216 using the automatic placement machine, a high potential difference is generated between the floating positioning mark and the adjacent electronic component 216, and it is easy to find that the positioning mark has a flashover phenomenon and the electronic component 216 is burned together. Compared with the comparative example, using the conductive pattern 106 according to the embodiment of the present invention including the positioning mark 106M partially exposed by the protective layer 108 can avoid the flashover phenomenon and the damage of the electronic component 216, and thus has a better product yield.

In summary, although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs can make various modifications and retouching without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope defined in the appended patent application.

102: printed circuit board 104: substrate 106: conductive pattern 106C: conductive contact 106K: aperture 106M: positioning mark 108: protective layer 108K: opening 108T: through hole 110: conductive layer 112: insulating layer 214: circuit 216: electronic component

FIG. 1 is a schematic top view of a circuit board structure according to an embodiment of the present invention. Figure 2 is a cross-sectional view of the circuit board structure of Figure 1 drawn along line AB.

102: Printed circuit board

104: substrate

106: conductive pattern

106K: Pore

106M: positioning mark

108: protective layer

108K: opening

110: conductive layer

112: Insulation

Claims (9)

A circuit board structure includes a printed circuit board including: a substrate; a conductive pattern on the substrate; a protective layer covering the conductive pattern and exposing a portion of the conductive pattern as a positioning mark, the The positioning mark has a ring shape. The circuit board structure as described in item 1 of the patent application scope, wherein the conductive pattern with the positioning mark is electrically connected to a ground. The circuit board structure as described in item 1 of the scope of the patent application further includes an electronic component on the protective layer and electrically connected to the conductive pattern with the positioning mark. The circuit board structure as described in item 3 of the patent application scope, wherein the electronic component includes a light emitting device, a passive component device, or an integrated electronic component. The circuit board structure as described in item 1 of the patent application scope, wherein the positioning mark has a hole corresponding to the hollow portion of the ring shape and exposes the substrate. The circuit board structure as described in item 1 of the patent application scope, wherein the protective layer has an opening that defines the outer edge of the ring shape. The circuit board structure as described in item 1 of the patent application scope, wherein the ring shape includes a polygonal ring shape or a ring shape. The circuit board structure as described in item 1 of the patent application scope, wherein the substrate includes a conductive layer and an insulating layer, the insulating layer being on the conductive layer. The circuit board structure as described in item 1 of the patent application scope, wherein the printed circuit board includes a metal-based printed circuit board (Metal Core PCB; MCPCB).

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