JPH0851282A - Method for manufacturing multilayer printed wiring board - Google Patents

Abstract

PURPOSE:To easily improve accuracy, reduce weight, and miniaturize a multilayer printed wiring board for the high density of a conductor pattern when manufacturing the multilayer printed wiring board. CONSTITUTION:A photosensitive photo solder resist 3 is directly applied to the roughened surface of a copper foil 1 and ultraviolet rays are selectively applied for developing a non-exposed part, etching is performed to create a substrate material 7 where a hole 6 for a via hole is formed the substrate material 7 is applied to a double-sided plate without including a glass cloth to create a multilayer plate, a through hole is formed, and a multilayer printed wiring board is manufactured by the circuit formation according to the subtractive method, thus enabling various kinds of characteristics including electrical characteristics to be equal to those of a multilayer plate manufactured by other methods, improving the housing capacity of the conductor pattern and the degree of freedom for wiring, reducing weight due to the reduced weight of a material, reducing working process, simplifying a preparation, and hence reducing cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a multilayer printed wiring board, and more particularly to a method for manufacturing a multilayer printed wiring board excellent in wiring efficiency and accommodation capacity of a conductor pattern, a base material and a substrate material.

[0002]

2. Description of the Related Art In recent years, electronic devices have been remarkably miniaturized, speeded up, and multifunctional, and the volume occupied by the printed wiring board in the device has become a problem. In addition, there is a need for a multilayer printed wiring board that can be through-hole joined in stages. (See, for example, Japanese Patent Publication No. 58-20195.) In a method for manufacturing a multilayer printed wiring board of this type, a double-sided plate having a land and a conductor pattern formed thereon, or a single-sided plate, or a multilayered plate is used. Alternatively, a photosensitive photo solder resist is applied on one side and cured by irradiation with ultraviolet rays, and the non-irradiated portion is washed as a via hole in the developing process to form a hole. However, in order to electrically connect, electroless plating is performed, and a conductive pattern is formed by a subtractive method or the like, but plating on a resin is very difficult and the number of steps is increased. is there.

[0003]

In order to solve these problems, an adhesive is interposed on a resin to improve the adhesion of plating, as is done in JP-A-3-229780. Although there is a method, it is difficult to deal with the uniformity of the thickness of the resin layer and the conductor pattern that has been densified in recent years, and there is a problem that the conductor pattern peels off when mounting components, so it is not commonly used. .

An object of the present invention is to provide a method for manufacturing a multilayer printed wiring board, a base material, and a method for accommodating a high density of conductor patterns in the multilayer printed wiring board, capable of achieving high precision, light weight and size reduction by an easy method. It is to provide a substrate material.

[0005]

[Means for Solving the Problems] The above object is to prepare a substrate in which a photosensitive photo solder resist is applied on one surface of a copper foil, and to form a hole for a via hole in this substrate to manufacture a substrate material. A method for producing a multilayer printed wiring board, characterized in that the side of the substrate material coated with the photosensitive photo solder resist is laminated on a double-sided plate or a single-sided plate on which a conductor pattern and lands are formed. It

Further, the substrate material is directly laminated on the double-sided plate or the single-sided plate without interposing a glass cloth between the copper foil and the double-sided plate or the single-sided plate. In addition, one surface of the copper foil is a roughened surface, the photosensitive photo solder resist is applied to the roughened surface, then exposed, developed, the exposed copper foil is etched to form a hole for a via hole. It is characterized by forming.

Further, specifically, in a method for manufacturing a multilayer printed wiring board, a step of preparing a single-sided roughened copper foil for a printed circuit board, and a photosensitive photo solder resist is applied to the roughened surface of the copper foil. A step of producing a base material having no glass cloth, a step of selectively irradiating the photosensitive photo solder resist with ultraviolet rays, and developing the hole portion for a via hole as unexposed; The surface of the copper-clad board is photo-etched to form conductor patterns and lands on both sides or one side of the board by masking the exposed surface and etching to form a board material with holes for via holes. And the process of manufacturing a double-sided plate or a single-sided plate,
A step of adhering the photosensitive photo solder resist side of the substrate material to a multi-layer board without interposing a glass cloth on both sides or one side of the double-sided board or single-sided board, and the via hole hole of the multi-layer board. A through hole for a through hole at a position other than the above, and a step of forming a through hole at the same time as forming a conductor pattern and a via hole in the copper foil layer of the multilayer board by circuit formation by the subtractive method. It is characterized by that.

Further, the following steps are carried out by sequentially applying the photosensitive photo solder resist side of the plurality of substrate materials to the double-sided plate or the single-sided plate without interposing a glass cloth, and a conductive pattern by a subtractive method or the like. It is also possible to form a multilayer board by forming the land a predetermined number of times, and to form a through hole for a through hole in the multilayer board at a place other than the via hole hole.

Further, the photosensitive photo solder resist of the base material is made of synthetic resin or modified resin of acrylic, epoxy, or polyimide resin, and the copper foil of the base material is manufactured by a rolling method, an electrolytic method or the like. Copper plates can be used.

The substrate according to the present invention is characterized in that a roughened surface of the copper foil is directly coated with a photosensitive photo solder resist without having a glass cloth, and the substrate material according to the present invention is A hole for a via hole is formed in a base material which is directly coated with a photosensitive photo solder resist without having a glass cloth on the roughened surface of the copper foil.

[0011]

According to the above construction, since the glass cloth provided in the conventional multilayer printed wiring board is not interposed between the substrate and the substrate, the use of the photosensitive photo solder resist facilitates the formation of via holes, through holes, etc. By reducing the material, it is possible to reduce the size and weight. Further, since the photosensitive photoresist is used, tens of thousands of holes can be instantly punched, and the punching size can be continuously obtained. Therefore, it is possible to manufacture a high-density and small-sized multilayer printed wiring board having a sufficient capacity for accommodating the conductor pattern.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are process diagrams of this embodiment, which are cross-sectional views in each process of manufacturing a four-layer printed wiring board. This example includes the following steps.

First, as shown in step A of FIG.
A copper foil 1 having a roughened surface on one surface (lower surface in the figure) is prepared. Next, as shown in step B, a photosensitive photo solder resist 3 (photosensitive resin) is directly applied to the roughened surface 2 of the copper foil 1 to make a substrate 4 containing no glass cloth.
In addition, as a coating method, a coating method such as a roll coater, a spray, or a curtain coater method is used.

Next, as shown in step C, the film 5 is applied to the coated surface of the photosensitive photo solder resist 3 on the base material 4 to irradiate it with ultraviolet rays. The film 5 is for forming an exposed portion and an unexposed portion by ultraviolet rays on the photosensitive photo solder resist 3, and there are a negative type and a positive type. According to the negative mold, the exposed portion is cured and the unexposed portion is dissolved. The opposite is true for positive type. In this embodiment, a negative type film is used.

Next, as shown in step D of FIG. 2, in the present embodiment, a portion (unexposed portion) not irradiated with ultraviolet rays is
Forming holes 6 for via holes by development, and then
As shown in step E, the copper foil 1 is etched to form the copper foil 1,
A substrate material 7 is prepared by forming a via hole 6 penetrating the photosensitive photo solder resist 3. At this time, the surface of the copper foil 1 where the copper is exposed is masked on the entire surface with a masking tape 8 or the like so as not to come into contact with the etching solution of copper chloride or iron chloride. Make more holes 6 open. The masking tape 8 also serves as a reinforcing material for the substrate material 7.

Next, as shown in step F, a double-sided plate 10 on which lands and conductor patterns 9 are formed is prepared,
As shown in step G, the substrate material 7 having the via holes 6 formed thereon is attached to both surfaces of the double-sided plate 10 with the photosensitive photo solder resist 3 side facing the double-sided plate 10 side without interposing glass cloth. A laminating press for producing a multilayer printed wiring board can be used as a sticking method. In this way, the via hole 6 can be formed, and at this time, the hole 6 is washed with a chemical such as permanganate if necessary. Although the double-sided plate 10 is used in this embodiment, the manufacturing process is the same even if a single-sided plate or a multi-layered plate is used instead.

Next, as shown in step H, a hole 11 for a through hole penetrating the land or the base material is formed, and a circuit pattern is formed by the subtractive method to form a conductor pattern on one layer of the copper foil of the base material. And a via hole is formed at the same time as a through hole is formed. That is, as shown in step H, copper plating with a thickness of 20 μm is electrolessly and electrolytically plated, and a conductor pattern is reversely formed using a photoresist, and solder plating 12 is formed with a thickness of 8 to 10 μm.
Then, the photoresist is peeled off and etched to form the conductor pattern 13, and the substrate 14 of the multilayer printed wiring board is manufactured.

According to this embodiment, since the photosensitive photoresist is used, the hole size for the via hole can be freely selected and a large number of holes can be formed at the same time. It is possible to manufacture a multilayer printed wiring board.

[0019]

As described above, according to the present invention,
The various characteristics such as heat resistance and electric characteristics are no different from those of the multi-layer board manufactured by other manufacturing methods, the capacity for accommodating the conductor pattern is significantly improved, and the wiring between layers can be freely performed. Further, since the material can be reduced, the weight can be reduced, the number of working steps can be reduced, and the manufacturing method can be simplified, so that the cost can be reduced. Therefore, it is widely applied and extremely industrially useful in the field of high-density electronic devices.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of the present invention and illustrating steps A to C.

FIG. 2 is a cross-sectional view for explaining steps D to E of this embodiment.

FIG. 3 is a cross-sectional view for explaining steps F to H of this embodiment.

[Explanation of symbols]

 1 Copper Foil 2 Roughened Surface 3 Photosensitive Photo Solder Resist 4 Base Material 5 Film 6 Via Hole 7 Substrate Material 8 Masking Tape 9 Conductor Pattern 10 Double Sided Board 11 Through Hole 12 Plating 13 Conductor Pattern 14 Substrate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display H05K 3/06 B

Claims (9)

[Claims] 1. A base material prepared by coating a photosensitive photo solder resist on one surface of a copper foil, and forming holes for via holes in the base material to manufacture a substrate material. A method for manufacturing a multilayer printed wiring board, characterized in that a side coated with a photo solder resist is laminated on a double-sided plate or a single-sided plate on which a conductor pattern and lands are formed. 2. The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the substrate material is formed on both surfaces of the copper foil and the double-sided board or the single-sided board without interposing a glass cloth. A method for producing a multilayer printed wiring board, which comprises laminating directly on a board or a single-sided board. 3. The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the substrate material has one surface of the copper foil as a roughened surface, and the photosensitive photosolder resist is applied to the roughened surface. Next, a method for manufacturing a multilayer printed wiring board, which comprises exposing and developing, and etching the exposed copper foil to form holes for via holes. 4. A method for manufacturing a multilayer printed wiring board, comprising the steps of preparing a single-sided roughened copper foil for a printed circuit board, and applying a photosensitive photo solder resist to the roughened surface of the copper foil to form a glass cloth. A step of producing a base material, a step of selectively irradiating the photosensitive photo solder resist with ultraviolet rays, and developing the hole portion for the via hole as unexposed; and a surface where the copper foil is exposed. A step of producing a substrate material with masking and etching to form holes for via holes; and photoetching copper of a copper-clad substrate, forming conductor patterns and lands on both sides or one side of the substrate to form a double-sided board or A step of producing a single-sided plate, on both sides or one side of the double-sided plate or the single-sided plate,
A step of manufacturing a multilayer board by pasting the photosensitive photo solder resist side of the substrate material without interposing a glass cloth, and forming a through hole for a through hole at a position other than the via hole hole of the multilayer board. A step of forming a conductor pattern and a via hole in the copper foil layer of the multilayer board by forming a circuit by a subtractive method, and forming a through hole at the same time, and a method of manufacturing a multilayer printed wiring board. . 5. A method for manufacturing a multilayer printed wiring board, comprising the steps of preparing a single-sided roughened copper foil for a printed circuit board, and applying a photosensitive photo solder resist to the roughened surface of the copper foil to form a glass cloth. A step of producing a base material, a step of selectively irradiating the photosensitive photosolder resist with ultraviolet rays, and developing the hole portions for via holes as unexposed, and a surface where the copper foil is exposed A step of masking and etching to form a substrate material having holes for via holes, and photoetching copper of a copper-clad substrate, forming conductor patterns and lands on both sides or one side of the substrate A step of producing a single-sided plate, and a step of sequentially forming the photosensitive photo solder resist side of the plurality of substrate materials on the double-sided plate or the single-sided plate without interposing a glass cloth. A step of forming a multilayer board by performing a subsequent bonding, forming a conductive pattern and a land by a subtractive method a predetermined number of times, and a step of forming a through hole for a through hole in a location other than the via hole hole of the multilayer board. A method for manufacturing a multilayer printed wiring board, comprising: 6. The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the photosensitive photosolder resist of the base material is a synthetic resin of acrylic, epoxy, or polyimide resin, or a modified resin. A method for manufacturing a multilayer printed wiring board, which is made of a resin. 7. The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the copper foil of the base material is a copper plate manufactured by a rolling method, an electrolytic method, or the like. A method for manufacturing a characteristic multilayer printed wiring board. 8. A photosensitive photosolder resist used for manufacturing the multilayer printed wiring board according to claim 1, wherein the roughened surface of the copper foil is directly provided with a photosensitive photosolder resist without a glass cloth. A base material characterized by being applied. 9. A photosensitive photosolder resist used for manufacturing a multilayer printed wiring board according to claim 1, which is directly provided on the roughened surface of the copper foil without a glass cloth. A substrate material, wherein holes for via holes are formed in the applied base material.