Circuit Board

Abstract

To provide a circuit board that prevents conditions that would corrode or oxidize the circuit layers. [Solution] A circuit board 100 includes a substrate 110, a circuit layer 120, a solder resist layer 130, and at least one moisture barrier layer 140, 150, 160. The circuit layer 120 is disposed on the substrate 110, and the solder resist layer 130 covers the circuit layer 120 and exposes a plurality of inner leads and a plurality of outer leads of the circuit layer 120. Each of the moisture barrier layers 140, 150, 160 covers the solder resist layer 130, and the circuit layer 120 and the solder resist layer 130 are located between the substrate 110 and each of the moisture barrier layers 140, 150, 160. Each of the moisture barrier layers 140, 150, 160 blocks liquid or moisture and prevents the liquid or moisture from penetrating the solder resist layer 130 and the circuit layer 120 and corroding or oxidizing the circuit layer 120.

Description

[Technical field]

[0001] The present invention relates to a circuit board, and more particularly to a circuit board for preventing conditions that corrode or oxidize the circuit layers. [Background technology]

[0002] Fig. 1 is a cross-sectional view showing a conventional circuit board 10. As shown in Fig. 1, in the conventional circuit board 10, a circuit layer 12 is formed on a substrate 11, and then the circuit layer 12 is covered with a solder resist layer 13. Summary of the Invention [Problem to be solved by the invention]

[0003] However, in conventional circuit boards, liquid or moisture adheres to the solder resist layer 13 during the manufacturing and transportation process or in the storage environment, and permeates through the solder resist layer 13 into the circuit layer 12, oxidizing the circuit layer 12 and causing a short circuit in the circuit layer 12. Furthermore, if the liquid or moisture contains a corrosive element (e.g., chlorine), the corrosive element will use the liquid or moisture as a carrier to permeate through the solder resist layer 13 into the circuit layer 12, corroding the circuit layer 12 and even causing a break in the circuit layer 12, thereby compromising the reliability of the circuit board 10.

[0004] Therefore, the inventor believed that the above-mentioned shortcomings could be improved, and after extensive research, he came up with the present invention, which effectively improves the above-mentioned problems through rational design.

[0005] The present invention has been made in consideration of the above circumstances, and its object is to provide a circuit board that uses at least one moisture barrier layer to prevent liquid or moisture from penetrating into the solder resist layer and circuit layer, thereby preventing the circuit layer from being oxidized or corroded. [Means for solving the problem]

[0006] In order to solve the above problems, the circuit board of the present invention adopts the following measures. A circuit board according to one aspect of the present invention includes a substrate, a circuit layer, a solder resist layer, and a first moisture barrier layer. The circuit layer is disposed on the substrate, and the circuit layer has a plurality of inner leads and a plurality of outer leads. The solder resist layer covers the circuit layer, but does not cover each of the inner leads and each of the outer leads. The first moisture barrier layer covers the solder resist layer, and the circuit layer and the solder resist layer are located between the substrate and the first moisture barrier layer. The moisture transmission rate (WVTR) of the first moisture barrier layer is 1x10 -2 g / m 2 ·day or less. Effect of the Invention

[0007] Thus, the present invention provides the following advantages. The present invention blocks liquid or moisture using a first moisture barrier layer, thereby preventing liquid, moisture, or corrosive elements (e.g., chlorine) carried by liquid or moisture from penetrating the solder resist layer and circuit layer and oxidizing or corroding the circuit layer, thereby preventing the reliability of the circuit board from being impaired.

[0008] Other features of the present invention will become apparent from the description of this specification and the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing a conventional circuit board. [Diagram 2] 1 is a plan view of a circuit board according to an embodiment of the present invention; [Diagram 3] 1 is a cross-sectional view of a circuit board according to an embodiment of the present invention. [Figure 4] 1 is a cross-sectional view of a circuit board according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiment, and various forms may be adopted as long as they fall within the technical scope of the present invention.

[0011] First, a specific embodiment of the circuit board of the present invention will be described with reference to FIGS.

[0012] 2 and 3, the circuit board 100 of the present invention includes a substrate 110, a circuit layer 120, a solder resist layer 130, and a first moisture barrier layer 140. The circuit layer 120 is disposed on the substrate 110, and includes a number of inner leads 121 and a number of outer leads 122, each of which is used to electrically connect a chip, and each of which is used to electrically connect other electronic elements (e.g., a display panel). The solder resist layer 130 covers the circuit layer 120, but does not cover the inner leads 121 and the outer leads 122.

[0013] 3, the first moisture barrier layer 140 covers the solder resist layer 130, and the circuit layer 120 and the solder resist layer 130 are located between the substrate 110 and the first moisture barrier layer 140. The moisture transmission rate (WVTR) of the first moisture barrier layer 140 is 1×10 -2 g / m 2 ·day or less, the thickness of the first moisture barrier layer 140 is less than 50 μm, and the material of the first moisture barrier layer 140 may be selected from copper, aluminum, polyvinylidene difluoride (PVDF), or polytetrafluoroethylene (PTFE). Preferably, the moisture transmission rate (WVTR) of the first moisture barrier layer 140 is less than 0.0 g / m 2 ·day.

[0014] As shown in FIG. 3, the projection area 141 of the first moisture barrier layer 140 is located on the substrate 110, the solder resist layer 130 is located in the projection area 141 of the first moisture barrier layer 140, and the first moisture barrier layer 140 completely covers the solder resist layer 130.

[0015] In this case, as shown in Fig. 3, in this embodiment, the circuit board 100 further includes a second moisture barrier layer 150, and the first moisture barrier layer 140 is integrally bonded to the solder resist layer 130 via the second moisture barrier layer 150. The moisture permeability of the second moisture barrier layer 150 is 10 g / m 2 ·day or less, and the thickness of the second moisture barrier layer 150 is 80 μm or less. The second moisture barrier layer 150 has adhesiveness, and is preferably selected from pressure-sensitive adhesive materials such as acrylic and epoxy resin.

[0016] 4, in another embodiment, the circuit board 100 further includes a third moisture barrier layer 160, which covers the first moisture barrier layer 140. The moisture permeability of the third moisture barrier layer 160 is 0.6 g / m 2 ·day or less, and the thickness of the third moisture barrier layer 160 is 50 μm or less. The material of the third moisture barrier layer 160 is selected from moisture-proof materials such as polyimide (PI) and polyethylene terephthalate (PET).

[0017] As shown in FIG. 4 , the projection area 161 of the third moisture barrier layer 160 is located on the substrate 110, the first moisture barrier layer 140 is located in the projection area 161 of the third moisture barrier layer 160, and the third moisture barrier layer 160 completely covers the first moisture barrier layer 140.

[0018] 4, the circuit board 100 further includes an adhesive layer 170, and the third moisture barrier layer 160 is attached to the first moisture barrier layer 140 by the adhesive layer 170, so that the first moisture barrier layer 140 is preferably integrally bonded to the third moisture barrier layer 160. The moisture permeability of the adhesive layer 170 is 10 g / m 2·day or less, and the thickness of the adhesive layer 170 is 80 μm or less.

[0019] As shown in FIG. 3, when liquid or moisture adheres to the first moisture barrier layer 140, the first moisture barrier layer 140 or the first moisture barrier layer 140 and the second moisture barrier layer 150 block the liquid or moisture, preventing the liquid, moisture, or corrosive elements (e.g., chlorine) carried by the liquid or moisture from penetrating into the solder resist layer 130 and the circuit layer 120, and preventing the circuit layer 120 from oxidizing or corroding, thereby preventing the reliability of the circuit board 100 from being impaired.

[0020] As shown in FIG. 4, when liquid or moisture adheres to the third moisture barrier layer 160, the third moisture barrier layer 160, the first moisture barrier layer 140, and the second moisture barrier layer 150 block the liquid or moisture, preventing the liquid, moisture, or corrosive elements (e.g., chlorine) from penetrating into the solder resist layer 130 and the circuit layer 120, preventing the circuit layer 120 from oxidizing or corroding, and preventing the reliability of the circuit board 100 from being impaired.

[0021] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0022] 10 Circuit Board 11 Substrate 12 circuit layers 13 Solder resist layer 100 Circuit Board 110 Substrate 120 circuit layers 121 Inner Lead 122 Outer lead 130 Solder resist layer 140 First moisture barrier layer 141 Projection area 150 Second Moisture Barrier Layer 160 3rd Moisture Barrier Layer 161 Projection area 170 Adhesive layer

Claims

1. A substrate; a circuit layer disposed on the substrate and having a plurality of inner leads and a plurality of outer leads; a solder resist layer that covers the circuit layer and exposes each of the inner leads and each of the outer leads; The solder resist layer is coated and the moisture permeability is 1x10 -2 g / m 2 a first moisture barrier layer having a thermal conductivity of 1000 .mu.m or less, the first moisture barrier layer positioning the circuit layer and the solder resist layer between the substrate and the first moisture barrier layer.

2. 2. The circuit board of claim 1, wherein a projection area of ​​the first moisture barrier layer is located on the substrate, the solder resist layer is located in the projection area of ​​the first moisture barrier layer, and the first moisture barrier layer completely covers the solder resist layer.

3. 2. The circuit board according to claim 1, wherein the first moisture barrier layer has a thickness of 50 [mu]m or less.

4. a second moisture barrier layer, the first moisture barrier layer being integrally bonded to the solder resist layer via the second moisture barrier layer, and the moisture permeability of the second moisture barrier layer being 10 g / m 2 2. The circuit board according to claim 1, characterized in that the resistance is less than or equal to 1 day.

5. The circuit board according to claim 4 , wherein the second moisture barrier layer has adhesive properties.

6. 6. The circuit board according to claim 5, wherein the second moisture barrier layer has a thickness of 80 [mu]m or less.

7. a third moisture barrier layer covering the first moisture barrier layer, the third moisture barrier layer having a moisture permeability of 0.6 g / m 2 5. The circuit board according to claim 1, wherein the resistance is less than or equal to 1 day.

8. 8. The circuit board of claim 7, wherein the projection area of ​​the third moisture barrier layer is located on the substrate, the first moisture barrier layer is located in the projection area of ​​the third moisture barrier layer, and the third moisture barrier layer completely covers the first moisture barrier layer.

9. 8. The circuit board according to claim 7, wherein the third moisture barrier layer has a thickness of 50 [mu]m or less.

10. 8. The circuit board according to claim 7, further comprising an adhesive layer, the third moisture barrier layer being attached to the first moisture barrier layer by the adhesive layer.

11. The moisture permeability of the adhesive layer is 10 g / m 2 11. The circuit board according to claim 10, characterized in that the resistance is less than or equal to .day.

12. 12. The circuit board according to claim 11, wherein the adhesive layer has a thickness of 80 [mu]m or less.

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