Circuit board

Abstract

We provide circuit boards. [Solution] The circuit board 100 comprises 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 installed on the substrate 110, and the solder resist layer 130 covers the circuit layer 120, while exposing multiple inner leads and multiple outer leads of the circuit layer 120. Each moisture barrier layer 140, 150, 160 covers the solder resist layer 130, positioning the circuit layer 120 and the solder resist layer 130 between the substrate 110 and each moisture barrier layer 140, 150, 160. Each moisture barrier layer 140, 150, 160 blocks liquid or moisture, preventing liquid or moisture from seeping into the solder resist layer 130 and the circuit layer 120 and causing corrosion or oxidation of 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 the circuit layer from being corroded or oxidized.

Background Art

[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, after forming a circuit layer 12 on a substrate 11, the circuit layer 12 is covered with a solder resist layer 13.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, in the conventional circuit board, during the manufacturing, transportation process or storage environment, liquid or moisture adheres to the solder resist layer 13, penetrates through the solder resist layer 13 into the circuit layer 12, oxidizes the circuit layer 12, and further causes a short circuit in the circuit layer 12. Also, when the liquid or moisture contains corrosive elements (e.g., chlorine), the corrosive elements penetrate through the solder resist layer 13 into the circuit layer 12 with the liquid or moisture as a carrier, corrode the circuit layer 12, and further cause a cut in the circuit layer 12, impairing the reliability of the circuit board 10.

[0004] Therefore, the inventor of the present invention considered that the above drawbacks could be improved, and as a result of intensive studies, reached the proposal of the present invention that effectively improves the above problems through a reasonable design.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to provide a circuit board that blocks liquid or moisture from penetrating into the solder resist layer and the circuit layer by at least one moisture barrier layer, and does not oxidize or corrode the circuit layer.

Means for Solving the Problems

[0006] In order to solve the above problems, the circuit board of the present invention employs the following means. A circuit board according to one aspect of the present invention comprises a substrate, a circuit layer, a solder resist layer, and a first moisture barrier layer. The circuit layer is installed on the substrate and 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 positions the circuit layer and the solder resist layer between the substrate and the first moisture barrier layer. The moisture permeability (WVTR) of the first moisture barrier layer is 1 x 10⁻¹⁶. -2 g / m 2 It is less than or equal to one day. [Effects of the Invention]

[0007] Thus, the present invention provides the following effects. The present invention prevents liquids or moisture from seeping into the solder resist layer and circuit layer, thereby preventing oxidation or corrosion of the circuit layer, by blocking liquids or moisture with a first moisture barrier layer, and thus maintaining the reliability of the circuit board.

[0008] Other features of the present invention will be made clearer by description in this specification and the accompanying drawings. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view showing a conventional circuit board. [Figure 2] This is a plan view showing a circuit board according to one embodiment of the present invention. [Figure 3] This is a cross-sectional view showing a circuit board according to one embodiment of the present invention. [Figure 4] This is a cross-sectional view showing a circuit board according to one embodiment of the present invention. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited in any way to the embodiments described below, and can take various forms as long as they fall within the technical scope of the present invention.

[0011] First, an example of a specific embodiment of the circuit board of the present invention will be described with reference to Figures 2 to 4.

[0012] As shown in Figures 2 and 3, the circuit board 100 according to the present invention comprises a substrate 110, a circuit layer 120, a solder resist layer 130, and a first moisture barrier layer 140. The circuit layer 120 is installed on the substrate 110 and includes a plurality of inner leads 121 and a plurality of outer leads 122, each inner lead 121 used to electrically connect chips and each outer lead 122 used to electrically connect other electronic elements (e.g., display panels). The solder resist layer 130 covers the circuit layer 120 but does not cover each inner lead 121 and each outer lead 122.

[0013] As shown in Figure 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 positioned between the substrate 110 and the first moisture barrier layer 140. The moisture permeability (WVTR) of the first moisture barrier layer 140 is 1 x 10⁻¹⁰ -2 g / m 2 The moisture barrier layer is less than or equal to 1 day, the thickness of the first moisture barrier layer 140 is 50 μm or less, 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 permeability (WVTR) of the first moisture barrier layer 140 is 0.0 g / m². 2 It is a day.

[0014] As shown in Figure 3, the projection region 141 of the first moisture barrier layer 140 is located on the substrate 110, the solder resist layer 130 is located within the projection region 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 Figure 3, the circuit board 100 further comprises 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 / m². 2 The moisture barrier layer is less than or equal to 1 day, and the thickness of the second moisture barrier layer 150 is 80 μm or less. The second moisture barrier layer 150 is adhesive and is preferably selected from pressure-sensitive adhesive materials such as acrylic or epoxy resin.

[0016] Next, as shown in Figure 4, in another embodiment, the circuit board 100 further comprises a third moisture barrier layer 160, and the third moisture barrier layer 160 covers the first moisture barrier layer 140. The moisture permeability of the third moisture barrier layer 160 is 0.6 g / m². 2 The moisture barrier layer is less than or equal to 50 μm in thickness. The material of the third moisture barrier layer 160 is selected from moisture-resistant materials such as polyimide (PI) and polyethylene terephthalate (PET).

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

[0018] As shown in Figure 4, the circuit board 100 further comprises an adhesive layer 170, and the third moisture barrier layer 160 is preferably attached to the first moisture barrier layer 140 by the adhesive layer 170, thereby integrally bonding the first moisture barrier layer 140 with the third moisture barrier layer 160. The moisture permeability of the adhesive layer 170 is 10 g / m². 2·It is below ·day, 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 and 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 being oxidized or corroded, so as not to impair the reliability of the circuit board 100.

[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 from penetrating into the solder resist layer 130 and the circuit layer 120, and preventing the circuit layer 120 from being oxidized or corroded, so as not to impair the reliability of the circuit board 100.

[0021] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in 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 Reference Numerals

[0022] 10 Circuit board 11 Substrate 12 Circuit layer 13 Solder resist layer 100 Circuit board 110 Substrate 120 Circuit layer 121 Inner lead 122 Outer lead 130 Solder resist layer 140 First moisture barrier layer 141 Projection area 150 Second moisture barrier layer 160 Third moisture barrier layer 161 Projection area 170 Adhesive layer

Claims

1. circuit board and A circuit layer installed on the substrate and having multiple inner leads and multiple outer leads, A solder resist layer covering the circuit layer and exposing each of the inner leads and each of the outer leads, The aforementioned solder resist layer is coated, and the moisture permeability is 1x10 -2 g / m 2 A circuit board characterized by comprising: a first moisture barrier layer having a moisture content of less than or equal to 1 day, wherein the circuit layer and the solder resist layer are positioned between the substrate and the first moisture barrier layer.

2. The circuit board according to claim 1, characterized in that the projection region of the first moisture barrier layer is located on the substrate, the solder resist layer is located within the projection region of the first moisture barrier layer, and the first moisture barrier layer completely covers the solder resist layer.

3. The circuit board according to claim 1, characterized in that the thickness of the first moisture barrier layer is 50 μm or less.

4. The first moisture barrier layer is further comprising 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 is 10 g / m². 2 The circuit board according to claim 1, characterized in that it is less than or equal to 1 day.

5. The circuit board according to claim 4, characterized in that the second moisture barrier layer is adhesive.

6. The circuit board according to claim 5, characterized in that the thickness of the second moisture barrier layer is 80 μm or less.

7. The first moisture barrier layer is further covered by a third moisture barrier layer, the moisture permeability of the third moisture barrier layer being 0.6 g / m² 2 The circuit board according to claim 1 or 4, characterized in that it is less than or equal to 1 day.

8. The circuit board according to claim 7, characterized in that the projection region of the third moisture barrier layer is located on the substrate, the first moisture barrier layer is located within the projection region of the third moisture barrier layer, and the third moisture barrier layer completely covers the first moisture barrier layer.

9. The circuit board according to claim 7, characterized in that the thickness of the third moisture barrier layer is 50 μm or less.

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

11. The moisture permeability of the adhesive layer is 10 g / m². 2 The circuit board according to claim 10, characterized in that it is less than or equal to 1 day.

12. The circuit board according to claim 11, characterized in that the thickness of the adhesive layer is 80 μm or less.

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