JPH04206689A - Manufacture of multilayer printed wiring board - Google Patents

Abstract

PURPOSE:To make it possible to align an outer layer pattern with both a via hole and a through hole and enhance the yield of a product by pasting a film with the via hole prior to the integration of laminated layers. CONSTITUTION:After a via hole 1 of IVH and a through hole 2 for an AC layer and an FB layer are bored and the through hole is plated, an inner layer circuit is formed and laminated layers are pressed. During this process, the IVH installed inside and outside a product where no circuit pattern is formed is pasted with release tape from the inner layer side. A print positioning guide 3 is installed to the outer layer which is located at a position, responding to the via hole 1. Printing is carried out monitoring the hole positions of the IVH of the guide 3 and the through hole 2. If the inside display of the guide 3 does not cover the through hole and the via hole 1 during this operation, the deviation of the pad against hole positioning will be absorbed within the specification.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for manufacturing a multilayer printed wiring board.

(Prior art) Conventionally, in the manufacturing method of multilayer print 1 to wiring board, a hole is made at the location where both sides of a double-sided copper-clad laminate, in which copper foil is bonded to both sides of an insulating board, are connected, and the inner wall of the hole is A substrate with a circuit pattern formed on one side is alternately laminated with an inner layer circuit board on which a circuit has been processed in advance and an insulating layer. Then, the inner layer circuit board is laminated and integrated by heating and pressurizing, and the circuit surface of the board is turned inside through the insulating layer, and then the whole is penetrated into the multilayer laminate board, which is further heated and pressurized to integrate the layers. After drilling a through hole and metallizing the inside of the through hole, the outermost layer circuit is formed.

Further, at this time, the pattern of the outer layer is aligned using only the through holes so that the deviation of the etching resist with respect to the through holes is reduced.

(Problem to be solved by the invention) However, in the conventional method described above, pattern alignment of the outer layer is performed only using the through holes, which causes misalignment between the via hole and the outer layer via hole pad, resulting in the product of the printed wiring board. There were problems such as deterioration of yield.

Furthermore, the resin of the insulating layer flows into the hole due to heating and pressure when the layers are integrated, and the hole is closed by metallization of the inner wall of the through hole in the next process, so the via hole and the outer layer pattern are There were also problems such as not being able to align the positions.

This invention was made in order to solve the above-mentioned problems, and it is a multilayer printed wiring board that can align the outer layer pattern with respect to both via holes and through holes, and improve the product yield. A manufacturing method is provided.

(Means for Solving the Problems) In order to achieve the above object, the method for manufacturing a multilayer printed wiring board according to the present invention connects both sides of a double-sided steel-clad laminate in which copper foil is bonded to both sides of an insulating board. Holes are drilled at the locations, the inner walls of the holes are metallized, and a circuit pattern is formed on the negative side of the board. One or more inner circuit boards with pre-processed circuits and an insulating layer are alternately layered and heated and pressurized to laminate the board. A through hole is made through the integrated inner layer circuit board and the multilayer laminate board, which is integrated by heating and pressurizing the integrated inner layer circuit board with the circuit surface of the board facing inside through the above insulating layer. In a method for manufacturing a multilayer printed wiring board in which a circuit is formed by metallizing and selectively etching away unnecessary parts of the outermost layer of copper foil, the part where the circuit pattern is not formed is aligned with the double-sided copper-clad laminate. A first hole was provided for the board, and before lamination and integration with the inner layer circuit board, a film was pasted on the hole position of the board to prevent resin from entering the hole, and the lamination was integrated. Later, a second hole penetrating the multilayer laminate is provided in the vicinity of the first hole, and when forming an etching resist to be used for configuring the circuit of the outermost layer, the first hole is formed.
The second hole is characterized in that it is possible to align the etching resist with respect to both the first hole and the second hole so that the deviation of the etching resist becomes small.

(Function) As described above, according to the manufacturing method of the present invention, by pasting a film on the via hole before the lamination is completed, the position of the via hole can be confirmed after the lamination is completed.

Therefore, it is possible to align the outer layer pattern with respect to both the via hole and the through hole.

In this way, in addition to providing via holes in the outside of the product, before laminating it into a multilayer printed wiring board,
By pasting a film on the hole position of the via hole to prevent resin from entering the hole, and making it possible to align the outer layer pattern with respect to both the via hole and the through hole, the product The yield will be improved.

(Example) Hereinafter, an example of the method for manufacturing a multilayer printed wiring board according to the present invention will be described.

Note that FIG. 1 is a plan view illustrating the state of use of this invention;
FIG. 2 is a sectional view of a main part showing one embodiment of the manufacturing method of the present invention.

As shown in FIG. 2, the multilayer printed wiring board used in the method of manufacturing a multilayer printed wiring board of this embodiment is composed of a six-layer printed wiring board.

This 6-layer printed wiring board has 4 signal layers, of which AC
The FB layer and the FB layer are each formed in a pattern that is electrically conductive by IVH.

At this time, the manufacturing process first involves drilling the IVH via holes 1 and through holes 2 in the AC layer and FB layer,
After plating the through holes, the inner layer (, C
-F layer) circuit formation will be performed and lamination pressing will be performed.

At this time, the IVH provided inside and outside the product, on which no circuit pattern is formed, is pasted with release tape from the inner layer side.

In the outer layer at a position corresponding to the via hole 1, a printing alignment kite 3 is provided, as shown in FIG.

This guide display is configured to have dimensions that suppress the deviation between the via hole 1 and the through hole 2 to within 0.15 mm.

Therefore, after pressing, the outer layer is baked after drilling the through holes 2 and plating the through holes.

Here, the printing is performed while observing the IVH of the printing positioning guide 3 and the hole positions of the through holes 2 and via holes 1.

At this time, if the inner markings of the printing positioning guide 3 do not cover the through hole 2 and the via hole 1, it means that the slippage of the pad with respect to the hole position is within the specifications.

After baking the outer layer, the product is completed through etching, resist baking, and external processing.

(Effects of the Invention) As is clear from the configuration described above, according to the manufacturing method of the present invention, when forming an outer layer circuit, it is possible to reduce pattern deviation for both via holes and through holes. Because the structure allows for positioning so that the circuit pattern is not formed, via holes are provided outside the product, and the holes of the via holes are carefully aligned before being laminated together as a multilayer printed wiring board. By applying a film to the position to prevent resin from entering the hole, and by allowing alignment of the outer layer pattern with respect to both the via hole and the through hole,
This has effects such as improving product yield.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the guide for printing position alignment;
The figure is a sectional view showing the layer structure of a multilayer printed wiring board in the manufacturing method of the present invention. 1... Via hole 2... Through hole 3... Seizing positioning guide Figure 2

Claims (1)

[Claims] 1. A hole is drilled at the point where both sides of the double-sided copper-clad laminate are to be connected, with copper foil pasted on both sides of the insulating board, the inner wall of the hole is metallized, and a circuit pattern is formed on one side of the board. One or more inner layer circuit boards and insulating layers are alternately stacked and heated and pressurized to form an integrated laminated inner layer circuit board. A method for manufacturing a multilayer printed wiring board, in which a through hole is formed through an integrated multilayer laminate, the inside of the hole is metallized, and unnecessary parts of the outermost layer of copper foil are selectively etched away to form a circuit. In this step, a first hole for positioning is provided in the double-sided copper-clad laminate in a portion where the circuit pattern is not formed, and resin is prevented from entering the hole before laminating and integrating with the inner layer circuit board. In order to prevent this, a film is pasted on the hole position of the substrate, and after the lamination is integrated, a second hole is provided near the first hole to penetrate the multilayer laminate to form the outermost layer circuit. When forming the etching resist to be used in the process, the first
A method for manufacturing a multilayer printed wiring board, characterized in that the etching resist can be aligned with respect to both the first hole and the second hole so that the deviation of the etching resist is reduced.