KR100271793B1 - Method of connecting conductive lines in multi-layered printed circuit board - Google Patents

Abstract

PURPOSE: An interlayer wire connection method of multi-layer PCBs is provided to simplify manufacturing processes without using a via hole formation processing and a metallization processing. CONSTITUTION: A first circuit network wire(22) is formed on a resin(21) for PCB. After forming a first insulating layer(23) on the first circuit network wire(22), a second circuit network wire(26) is formed on the first insulating layer. Then, a first contact part is formed to electrically connect between the first and second circuit network wires(22,26) through the first insulating layer(23) by using a contact tool having a taper tip. After forming a second insulating layer(27) on the resultant structure, a third circuit network wire(28) is deposited on the second insulating layer. Also, a second contact part(250) is formed electrically connect between the third and second circuit network wires(28,26) via the second insulating layer(27) by using the contact tool having a taper tip. The contact tool applies a predetermined pressure in a vertical lower end direction and provides a high frequency vibration in a horizontal direction to form connection between interlayer wires.

Description

Method of connecting conductive lines in multi-layered printed circuit board

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting interlayer wiring of a multilayer printed circuit board. In particular, the present invention relates to a connection tool without forming via holes in the connection between interlayer wirings for electrical conduction of a multilayer resin circuit board. The present invention relates to a method for directly connecting by applying a high frequency and a constant pressure to the connection.

A printed circuit board (PCB) prints a necessary circuit by coating a conductive material such as copper foil on a paper epoxy or glass epoxy substrate and removes other copper foil portions. Components such as integrated circuit elements are attached to the circuit thus formed, and then electrical connection of the elements is achieved by soldering or the like. In general, if one side is used, but the circuit is complicated, both sides of the substrate are used or a printed circuit board is formed in multiple layers as in the case of the present invention.

Conventional technology 1 for electrically connecting metal wiring formed in each layer in a multilayer printed circuit board is formed by directly drilling a via hole using an electric drill or the like between the wiring layer and the adjacent wiring layer, and then exposed each This is a method of electrically connecting the wiring of the via hole to form a via metal by electroplating in the via hole. At this time, however, the prior art 1 is difficult to process a printed circuit board having a fine wiring network because the via hole is formed by mechanical work.

In addition, the conventional technology 2 is a metallization similar to the Fab process, which is an electrical connection between wiring layers in the manufacture of multilayer printed circuit boards, and an opening process of a pad portion for connection between the device and the wiring after the passivation layer is formed during the semiconductor device manufacturing process. After the via hole is formed by the metalization method, the connection between the wirings is formed.

1A to 1B are cross-sectional views illustrating a method for connecting interlayer wiring of a multilayer printed circuit board according to the related art.

In FIG. 1A, a first network wiring 2 is formed on a substrate resin 1 that forms part of a multilayer printed circuit board, and then an interlayer first insulating layer 3 is formed thereon. A second insulating layer 4 is formed on the first insulating layer 3 to define the opening of the first network wiring 2. After the photoresist is applied on the second insulating layer 4, a photolithography process is performed to remove a part of the second insulating layer 4, thereby forming a mask pattern 4 including the remaining second insulating layer 4. do.

In FIG. 1B, a portion of the first insulating layer 3 is etched and removed using the mask pattern 4 made of the remaining second insulating layer as an etch protective film. At this time, a part of the surface of the first wiring network 2 is exposed to form a via hole. The via metal 5 is formed by performing metal plating on the exposed surface of the first network metal wiring 2, the exposed side of the first insulating layer 3 and the side of the mask pattern 4, that is, via holes. At this time, the via metal 5 becomes a medium for electrically connecting the second network wiring and the first network wiring 2 to be formed later.

In FIG. 1C, the mask pattern 4 made of the remaining second insulating layer is etched and removed. Therefore, the surface of the first insulating layer 3, which is an interlayer insulating layer, and a part of the outer side surface of the via metal 5 are exposed.

In FIG. 1D, a second network wiring 6 is formed on the exposed surface of the first insulating layer 3 and the exposed via metal 5. The second network wiring 6 formed at this time is electrically connected to the first network wiring 2 via the via metal 5 as described above. Then, a third interlayer insulating layer 7 is formed on the second network wiring 6 to protect the wiring 6 from the surroundings.

Then, in the case of forming additional network wiring, the above process is repeated from the first network wiring forming step in the process of FIG. 1A to complete electrical connection of each interlayer wiring of the multilayer wiring.

As described above, the method of connecting the interconnection layer of the multilayer printed circuit board of the prior art 1 forms the via hole processing by a mechanical method. Therefore, since the size of the via hole requires an area of at least several hundred μm, the multilayer printed circuit board requiring high precision is required. It is not applicable, and in the related art 2, the number of metalization processes for forming the via metal is complicated, and thus, the manufacturing cost is high.

There is a problem that is easy to cause an image.

Accordingly, an object of the present invention is to physically compress by applying a high frequency and a constant pressure to a contact tool without forming via holes or via metals in a method of connecting interlayer wiring of a multilayer printed circuit board. The present invention provides a method for connecting interlayer wiring of a simplified multilayer printed circuit board that directly makes electrical connections.

In order to achieve the above objects, an interconnection method for interconnecting a multilayer printed circuit board according to the present invention includes a first step of forming a first network wiring on a resin for a printed circuit board, and a first insulating layer on the resin. A second step, a third step of forming a second network wiring on the first insulating layer, and a connecting mechanism having an end portion on the surface of the second network wiring to which the second network wiring and the first network wiring are to be connected; And the second network wiring in which the portion of the second circuit wiring in the vertical lower direction is applied to the upper surface of the first network wiring through the first insulating layer and is in contact with each other in the horizontal direction. A predetermined portion of the first network wiring and the second network wiring is given to the connecting mechanism by applying high frequency vibration to the crimping characteristics of the first network wiring. Comprises a fourth step of forming the at least one first connecting portion is brought into contact.

The present invention also provides a method of forming a second insulating layer having a flattened surface over a second network wiring when forming a network wiring formed in at least two respective insulating layers after forming the first connection portion, Forming a third network wiring; and a second connecting portion for electrically connecting the third network wiring and the second network wiring by using the connecting device on the third network wiring at the portion where the second network wiring and the third network wiring are to be connected. It further comprises repeating the step of forming.

1A to 1B are cross-sectional views illustrating an interlayer wiring connection method of a multilayer printed circuit board according to the related art.

2A to 2B are cross-sectional views illustrating an interlayer wiring connection method of a multilayer printed circuit board according to the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view illustrating an interlayer wiring connection method of a multilayer printed circuit board according to the present invention. The present invention relates to a method of applying high frequency, low temperature and constant pressure to a connection mechanism without via hole processing and via hole connecting metal forming process in each insulating layer or resin layer in the prior art.

In FIG. 2A, a first network wiring 22 is formed on a resin 21 for a substrate which forms part of a multilayer printed circuit board, and then formed by applying an interlayer first insulating layer 23 on the substrate 22. As shown in FIG. At this time, the first insulating layer 23 serves to insulate the first network wiring 22 and the second network wiring to be formed later.

In addition, a second network wiring 26 is formed on the first insulating layer 23.

In FIG. 2B, the first network wiring 22 and the second are connected by using a contact tool having a steeple at the end of the portion where the second network wiring 26 and the first network wiring 22 are to be connected. A first connection portion 25 is formed to electrically connect the network wiring 26. At this time, the connecting mechanism applies a predetermined pressure in the vertical lower direction and gives a high frequency vibration in the horizontal direction to form a connection between the interlayer wirings. That is, a part of the second circuit wiring penetrates the first insulating layer in a vertical lower direction to a connecting device having a spire shape on the surface of the second network wiring to which the second network wiring and the first network wiring are to be connected. Applying a pressure to contact the upper surface of the first network wiring and giving the connecting device high frequency vibration to improve the crimping characteristics of the second and first network wirings which are in contact with each other in a horizontal direction. At least one first connection portion for contacting a predetermined portion of the first network wiring and the second network wiring is formed.

In the first connection portion 25 formed in this manner, a part of the second network wiring 26 is recessed in the vertical lower direction so that the V-shaped cross section profile has a V-shaped point and the first network wiring 22 is formed. It is in physical contact with the surface of the circuit) to electrically connect the interlayer interconnections.

Therefore, the interlayer wiring of the multilayer printed circuit board without the formation of a separate via hole or a via hole metal and a reduction in processing steps that do not require a plating process is performed.

Further, in order to more securely connect the network wirings formed in the respective layers, or as required, a plurality of connection portions of the first network wiring and the second network wiring can be formed.

If more than 3 interlayer network wiring is needed, continue the following process.

In FIG. 2C, a second insulating layer 27 having a flattened surface is formed on the second network wiring 26 including the first connecting portion 25. Then, the third network wiring 28 is coated on the 27 to form.

In FIG. 2D, the portion where the second network wiring 26 and the third network wiring 28 are to be connected is connected to the third network wiring 28 by using a contact tool having a spigot shape as described above. A second connection portion 250 is formed to electrically connect the second network wiring 26. At this time, the connection mechanism also applies a predetermined pressure in the vertical lower direction and gives a high frequency vibration in the horizontal direction to form a connection between the interlayer wirings. The second connection part 250 formed as described above has a V-shape in which a portion of the third network wiring 28 is recessed in the vertical lower direction, and the V-shaped sharp portion is physically formed on the surface of the second network wiring 26. Contact to electrically interconnect the interlayer network wiring.

Also in this case, a plurality of connection portions between the third network wiring and the second network wiring can be formed in order to further ensure the connection of the network wiring formed in each layer.

After that, if another insulating layer is formed to form a network wiring thereon, the above process is repeated again from the second network wiring forming step in the wiring connection process shown in FIG. 2A. Complete electrical connection of each interlayer wiring.

Therefore, the present invention simplifies the process by eliminating the via hole forming process and the via metal metallization process for interlayer interconnection through the via hole in the interlayer wiring connection method of the multilayer printed circuit board having a plurality of layers. Since the electric drill is not used, there is an advantage of providing a method of manufacturing a printed circuit board having a very fine line width compared to the conventional via hole processing.

Claims (3)

A first step of forming a first network wiring on a resin for a printed circuit board, Forming a first insulating layer on the resin; Forming a second network wiring on the first insulating layer; A portion of the second network wiring penetrates the first insulating layer in a vertical lower direction to a connecting mechanism having a spire shape at an end portion on the surface of the second network wiring to which the second network wiring and the first network wiring are to be connected. The high pressure vibration is applied to the connection mechanism by applying pressure to contact the upper surface of the first network wiring and improving the crimping characteristics of the second network wiring and the first network wiring in mutual contact in the horizontal direction. 1. A method for connecting interlayer wiring of a multilayer printed circuit board, the method comprising: forming a at least one first connecting portion for contacting a network wiring with a predetermined portion of the second network wiring; The method of claim 1, wherein when forming a plurality of network wiring on the plurality of insulating layers and the plurality of insulating layers on the first insulating layer after forming the first connection portion, Forming a second insulating layer having a planarized surface over said second network wiring; Forming a third network wiring on the second insulating layer; Electrically connecting the third network wiring and the second network wiring by the method of the fourth step by using the connection mechanism on the third network wiring at the portion where the second network wiring and the third network wiring are to be connected. The method for connecting interlayer wiring of a multilayer printed circuit board further comprising repeating a plurality of steps of forming at least one second connection portion. The method according to claim 1, wherein the fourth step, a portion of the second network wiring in the first connection portion is recessed in the vertical lower direction so that the cross-sectional profile having a V-shaped pointed portion of the V-shaped point is the first And physically contacting the upper surface of the network wiring so as to electrically connect the first network wiring and the second network wiring to each other.