阅读说明：本技术 一种低成本低电阻值的导电浆灌孔线路板及其制作方法 (Low-cost low-resistance conductive paste hole filling circuit board and manufacturing method thereof ) 是由 王定锋 徐文红 于 2019-01-11 设计创作，主要内容包括：本发明涉及一种低成本低电阻值的导电浆灌孔线路板及其制作方法,具体而言,将一单面覆铜板制作完线路后,背面贴上热固胶膜,再一起冲孔或者钻孔,完成正面单面板的制作,再将另一单面覆铜板蚀刻或模切制作出电路,然后电路铜面对着正面单面板的热固胶面对位贴压粘合在一起,在孔位处形成杯状孔,再用模具将底部铜在孔处朝孔里顶,使孔变浅,孔底金属离杯口边的金属距离近了,然后,再在孔里及孔边施加导电浆,加热固化,上下两层金属在孔处通过导电浆导通,然后再做正面阻焊,即制成了新型的导电浆灌孔线路板,本发明依据材料电阻计算公式R＝ρL/S,其长度L就是孔的深度,孔越浅L值越小,电阻值就越小,导电浆用量少,成本低。(The invention relates to a low-cost low-resistance conductive paste hole filling circuit board and a manufacturing method thereof, and particularly relates to a low-cost low-resistance conductive paste hole filling circuit board and a manufacturing method thereof, wherein after a single-sided copper-clad plate is manufactured into a circuit, a thermosetting adhesive film is pasted on the back, then holes are punched or drilled together to manufacture a front single-sided panel, then the other single-sided copper-clad plate is etched or die-cut to manufacture a circuit, then the copper surfaces of the circuit are opposite to the thermosetting adhesive surface of the front single-sided panel, aligned and pressed together, cup-shaped holes are formed at hole positions, a die is used for ejecting bottom copper towards the inside of the hole at the hole positions, so that the hole is shallow, the metal at the bottom of the hole is close to the metal distance from the edge of the cup, then conductive paste is applied to the hole inside and the hole edge, heating and curing are carried out, the upper layer metal and the lower layer of the hole are conducted through the conductive paste, and then front resistance welding is carried out, so that the novel conductive paste hole filling circuit board is manufactured.)

1. A method for manufacturing a circuit board with conductive paste filled holes with low cost and low resistance value includes the steps of manufacturing a circuit on a single-sided copper-clad plate, attaching a thermosetting adhesive film to the back side of the circuit, punching or drilling the circuit together to manufacture a front single-sided panel, etching or die-cutting another single-sided flexible copper-clad plate to manufacture a circuit, aligning and bonding circuit copper surfaces to thermosetting adhesive surfaces of the front single-sided panel to form a cup-shaped hole at a hole position, wherein the copper at the bottom of the hole is complete or etched with a small hole, jacking bottom copper towards the inside of the hole at the hole position by a die to enable the hole to be shallow, enabling the metal at the bottom of the hole to be closer to metal at the edge of the cup, printing conductive paste from the front side or printing the conductive paste from the front side when the hole is formed at the bottom of the hole, sucking the conductive paste from the small hole at the back side, heating and curing, enabling upper and lower layers of metal to be, and then the front solder mask is made, so that the conductive paste hole-filling circuit board which can reduce the resistance value and the cost is manufactured.

2. A low-cost low-resistance conductive paste hole-filling circuit board comprises:

a bottom layer circuit;

an intermediate insulating layer;

a top layer circuit;

a cup-shaped via hole;

conducting paste;

solder resist on the surfaces of the two sides;

the conductive paste is arranged in the cup-shaped via hole, the cup-shaped via hole is connected with the bottom metal of the cup-shaped via hole and the surface metal of the hole edge to form conduction on two circuits, the cup-shaped via hole is provided with a complete or smaller small hole than the cup-shaped via hole, the connection distance of the conductive paste for connecting two layers of metal is smaller than the thickness of the middle insulating layer, the consumption and the resistance of the conductive paste are compared with the case that the cup-shaped via hole is flat, the consumption of the conductive paste is reduced, the resistance is reduced, and the conductive paste is covered by the solder resist layer or the surface of the conductive paste is exposed.

3. The circuit board of claim 1 or 2, wherein the conductive paste is a silver powder, a copper powder, a graphite powder, a mixture of any two or three of silver powder, copper powder and graphite powder, or a metal alloy powder.

4. The circuit board of claim 1 or 2, wherein the conductive paste is formed by mixing conductive material, adhesive polymer material and auxiliary agent.

5. A low cost, low resistance, conductive paste via board as claimed in claim 1 or 2, wherein said double-sided circuit board is a flexible circuit board or a rigid circuit board.

6. A low cost low resistance conductive paste via board as claimed in claim 1 or 2, wherein said hole is a circular hole or a shaped hole.

7. The circuit board of claim 1 or 2, wherein the surface solder mask is a coverlay solder mask or an ink solder mask.

8. The circuit board of claim 7, wherein the cover film is used as a surface solder mask to firmly cover the cured silver paste and prevent migration of silver particles.

Technical Field

The invention relates to the field of circuit boards and application thereof, in particular to a low-cost low-resistance conductive paste hole-filling circuit board and a manufacturing method thereof.

Background

The conventional conductive paste hole filling plate has the advantages that the insulating layer of the plate is thick, so that the hole is deep, the metal distance between two sides of the hole is long, the connection distance between the conductive paste filled into the hole and the metal on the two sides is long, the resistance value of the conductive paste filled into the hole and the metal on the two sides is large, the using amount of the conductive paste is large, and the cost is high.

In order to overcome the defects and the shortcomings, the cost can be reduced, and the resistance value can be reduced, the position of the circuit board needing to be conducted on two sides is designed to be a cup-shaped conducting hole, namely copper at the cup opening of the cup-shaped conducting hole is copper on a front circuit of the circuit board, metal copper at the cup bottom is copper on a back circuit, then the copper at the cup bottom is pushed to be flush or nearly flush from the back to the cup opening by utilizing the ductility of the copper, the distance between the copper at the cup bottom and the copper at the cup opening is shortened, the cup depth is reduced, then conductive paste is filled into the cup-shaped conducting hole, the using amount of the conductive paste is reduced, the resistance value of the conductive paste at the hole is reduced, the resistance value is reduced according to the resistance calculation formula R of the material rho L/S, the length L is the depth of the hole, and the shallower L value of the hole.

Disclosure of Invention

The invention relates to a low-cost low-resistance conductive paste hole filling circuit board and a manufacturing method thereof, and particularly relates to a low-cost low-resistance conductive paste hole filling circuit board and a manufacturing method thereof, wherein after a single-sided copper-clad plate is manufactured into a circuit, a thermosetting adhesive film is pasted on the back, then holes are punched or drilled together to manufacture a front single-sided panel, then the other single-sided copper-clad plate is etched or die-cut to manufacture a circuit, then the copper surfaces of the circuit are opposite to the thermosetting adhesive surface of the front single-sided panel, aligned and pressed together, cup-shaped holes are formed at hole positions, a die is used for ejecting bottom copper towards the inside of the hole at the hole positions, so that the hole is shallow, the metal at the bottom of the hole is close to the metal distance from the edge of the cup, then conductive paste is applied to the hole inside and the hole edge, heating and curing are carried out, the upper layer metal and the lower layer of the hole are conducted through the conductive paste, and then front resistance welding is carried out, so that the novel conductive paste hole filling circuit board is manufactured.

The invention provides a method for manufacturing a low-cost low-resistance conductive paste hole-filling circuit board, which comprises the steps of manufacturing a circuit by a single-sided copper-clad plate, sticking a thermosetting adhesive film on the back surface of the circuit, punching or drilling the circuit to manufacture a front single-sided panel, etching or die-cutting another single-sided flexible copper-clad plate to manufacture a circuit, sticking and bonding the copper surfaces of the circuit opposite to the thermosetting adhesive surface of the front single-sided panel in an aligned mode to form a cup-shaped hole at a hole position, wherein the copper at the bottom of the hole is complete or etched with a small hole, jacking the copper at the hole position by a die to ensure that the hole is shallow, the metal at the bottom of the hole is closer to the metal at the edge of the cup opening, then printing conductive paste from the front surface, or printing conductive paste from the front surface when the hole is formed at the bottom of the hole, sucking the conductive paste from the small hole at the back surface, and, the upper layer metal and the lower layer metal are conducted at the hole through the conductive paste, and then front resistance welding is carried out, so that the conductive paste hole-filling circuit board which can reduce the resistance value and the cost is manufactured.

The invention also provides a low-cost low-resistance conductive paste hole-filling circuit board, which comprises: a bottom layer circuit; an intermediate insulating layer; a top layer circuit; a cup-shaped via hole; conducting paste; solder resist on the surfaces of the two sides; the conductive paste is arranged in the cup-shaped via hole, the cup-shaped via hole is connected with the bottom metal of the cup-shaped via hole and the surface metal of the hole edge to form conduction on two circuits, the cup-shaped via hole is provided with a complete or smaller small hole than the cup-shaped via hole, the connection distance of the conductive paste for connecting two layers of metal is smaller than the thickness of the middle insulating layer, the consumption and the resistance of the conductive paste are compared with the case that the cup-shaped via hole is flat, the consumption of the conductive paste is reduced, the resistance is reduced, and the conductive paste is covered by the solder resist layer or the surface of the conductive paste is exposed.

According to a preferred embodiment of the present invention, the conductive paste hole-filling circuit board with low cost and low resistance value is characterized in that the conductive substance in the conductive paste is silver powder, copper powder, graphite powder, or a mixed powder of any two or three of silver powder, copper powder and graphite powder, or metal alloy powder.

According to a preferred embodiment of the present invention, the conductive paste-filled circuit board with low cost and low resistance value is characterized in that the conductive paste is formed by mixing a conductive substance, an adhesive polymer material and an auxiliary agent.

According to a preferred embodiment of the present invention, the conductive paste-filled circuit board with low cost and low resistance value is characterized in that the double-sided circuit board is a flexible circuit board or a rigid circuit board.

According to a preferred embodiment of the present invention, the conductive paste-filled via circuit board with low cost and low resistance value is characterized in that the hole is a circular hole or a special-shaped hole.

According to a preferred embodiment of the present invention, the conductive paste-filled circuit board with low cost and low resistance value is characterized in that the surface solder resist is a cover film solder resist or an ink solder resist.

According to a preferred embodiment of the present invention, the conductive paste-filled circuit board with low cost and low resistance value is characterized in that when the cover film is used as the surface solder mask, the cover film firmly covers the cured silver paste to prevent migration of silver particles.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below.

Drawings

The features, objects, and advantages of the present invention will become more apparent from the description set forth below when taken in conjunction with the drawings, a brief description of which follows.

Fig. 1 is a schematic cross-sectional view of a low-cost low-resistance via-hole circuit board with a copper via bottom at a cup-shaped hole according to a preferred embodiment of the present invention.

FIG. 2 is a cross-sectional view of a low-cost, low-resistance via-in-hole circuit board with a hole etched in the bottom copper metal of a cup-shaped hole according to another preferred embodiment of the present invention.

Detailed Description

The present invention will be described in detail below by taking preferred embodiments as examples.

It will be understood by those skilled in the art that the following descriptions are provided for purposes of illustration and description of certain preferred embodiments only and are not intended to limit the scope of the present invention.

1. And (3) putting the single-sided copper-clad plate on a screen printing machine, baking, solidifying by using screen printing line ink which is manufactured in advance according to design data, etching and manufacturing a top layer circuit 2 on an etching and film-removing horizontal production line, pasting a thermosetting adhesive film on the back, putting the circuit on an FPC (flexible printed circuit) drilling machine, drilling required holes according to the designed drilling data, and finishing the manufacturing of the front single-sided plate.

2. The other one-sided copper-clad plate is put on a screen printing machine, the screen printing plate screen printing line printing ink which is manufactured in advance according to the design data is baked and solidified, then etching and manufacturing a bottom layer circuit 1 on an etching film-removing horizontal production line, aligning and sticking the copper surface of the circuit to the thermosetting adhesive surface of the front single panel, pressing the circuit on a quick press at 180 ℃ and 1200kg, firmly bonding the bottom layer circuit 1 and the top layer circuit 2 by the thermosetting adhesive film, separating a middle insulating layer 3 between the top layer circuit 2 and the bottom layer circuit 1, forming a cup-shaped hole at the hole position, enabling the bottom metal copper of the hole to be complete, ejecting the copper of the bottom circuit 1 towards the inside of the hole at the hole position by using a mould, enabling the bottom metal copper of the cup-shaped via hole to be convex towards the cup opening direction, enabling the hole to be shallow, enabling the bottom metal of the hole to be close to the metal distance of the edge of the cup opening, and manufacturing the double-layer circuit board with the via hole (as shown in figure 1).

Or a small hole 1.1 is etched in the bottom metal copper, the copper of the bottom circuit 1 is pushed towards the inside of the hole at the hole by using a mould, the bottom metal copper of the cup-shaped via hole is raised towards the cup mouth, so that the hole becomes shallow, the metal distance between the bottom metal of the hole and the edge of the cup mouth is close, and the double-layer circuit board with the via hole is manufactured (as shown in figure 2).

3. The manufactured silk screen printing is used on a silk screen printing machine, the bottom metal copper of the hole is complete at the position of the through hole, the conductive paste 4 is printed on the top layer circuit 2 on the front surface, the conductive paste 4 is printed and poured into the through hole, meanwhile, the conductive paste 4 is adhered to the surface of the bottom copper of the hole, namely, the bottom layer circuit 1 and the top layer circuit 2 on the periphery of the hole, baking and curing are carried out, and the bottom layer circuit 1 and the top layer circuit 2 are connected and conducted through the conductive paste 4 in the through hole (as shown in figure 1).

Or, at the via hole, the bottom metal copper is etched with a small hole 1.1, the conductive paste 4 is printed from the top layer circuit 2 on the front surface, and the conductive paste 4 is sucked from the small hole 1.1 on the back surface, so as to make the conductive paste 4 more easily enter the hole, so that the conductive paste 4 is printed and poured in the via hole, the conductive paste 4 is simultaneously stuck to the bottom copper surface, namely the bottom layer circuit 1, and the top layer circuit 2 on the periphery of the hole, and is baked and cured, and the bottom layer circuit 1 and the top layer circuit 2 are connected and conducted through the conductive paste 4 in the via hole (as shown in fig. 2).

4. The top surface covering film 5 with the opened pad window 5.1 is attached to the top layer circuit 2 in an aligned mode, a part of conductive silver paste 4 is covered according to design, a part of conductive silver paste 4 is exposed, then the bottom surface covering film 6 is attached to the bottom layer circuit 1 in an aligned mode, then the top surface covering film 5, the top layer circuit 2, the bottom layer circuit 1 and the bottom surface covering film 6 are firmly bonded together on a quick press machine under the pressure of 180 ℃ and 1200kg, then the top surface covering film, the top layer circuit 2, the bottom layer circuit 1 and the bottom surface covering film 6 are placed in an oven, the baking and curing are carried out for 60 minutes under the temperature of 150 ℃, and then the conductive paste filling hole circuit board with low cost and low resistance is manufactured through the traditional manufacturing procedures of circuit boards such as silk-printing characters, baking and curing, OSP surface.

The position of the circuit board needing to be conducted on two sides is designed into a cup-shaped via hole, copper at the bottom of the cup is pushed to be flush or nearly flush from the back to the cup opening by utilizing the ductility of the copper, the distance between the copper at the bottom of the cup and the copper at the cup opening is shortened, the cup depth is reduced, and then the conductive paste is filled into the cup-shaped via hole, so that the using amount of the conductive paste is reduced, the resistance value of the conductive paste at the hole is reduced, according to the resistance calculation formula R of the material, the length L is the depth of the hole, and the shallower L value of the hole is, the smaller the resistance value is, the using amount of the conductive paste is less, and the cost is low.

The present invention is described in detail with reference to the accompanying drawings by using a specific embodiment of a low-cost low-resistance conductive paste via-filling circuit board and a method for manufacturing the same. It will be understood by those skilled in the art, however, that the foregoing is merely illustrative and descriptive of some specific embodiments and is not to be construed as limiting the scope of the invention, especially the scope of the claims.