KR0130458B1 - Printed wiring board and production thereof - Google Patents

Abstract

An outer circuit layer formed from a metal thin film layer on both sides of the inner layer circuit support via at least one inner layer circuit support and a prepreg, the inner layer circuit support formed on both sides of the insulating layer and the insulating layer A wiring board comprising a layer, wherein at least one inner layer circuit support or the outer circuit layer or both have recesses in a metal thin film layer filled with a conductor, the wiring board having at least one recess and at least one through hole filled with a conductor. Has high reliability and high wiring density.

Description

1A and 1B are cross-sectional views each showing main parts of a wiring board embodiment of the present invention.

2 is a cross-sectional view showing a main part of a wiring board of the prior art.

3 is a sectional view showing a main part of still another embodiment of a wiring board of the present invention.

4A and 4B are top views showing the essential parts of the wiring board embodiments of the present invention.

5a to 5e are cross-sectional views illustrating steps of an embodiment of the method of the present invention.

6A-6F are cross-sectional views illustrating steps of yet another embodiment of the method of the present invention.

7A-7H are cross-sectional views illustrating steps of yet another embodiment of the method of the present invention.

* Explanation of symbols for the main parts of the drawings

1: Insulation substrate 2, 21: Copper thin film

3, 31: fluid conductive material 4: wiring

5: prepreg

The present invention relates to a low cost printed wiring board having a high wiring density and a method for efficiently manufacturing the wiring board.

Conventional printed wiring boards can be fabricated by drilling holes at locations of copper-clad laminates requiring electrical connection, covering the walls of the holes with metal by electroless plating or electroplating, and by etching to eliminate the need for conductors (copper). A subtractive process comprising removing, an additive process comprising forming a conductor circuit for drilling a hole in an insulated substrate and electroless plating the wall of the hole as well as the required portion of the substrate. By a semi-additive method and the like, including the steps of drilling a hole, then removing the undesired portion of the copper thin film, and covering only the wall of the hole with metal by wireless plating. Was prepared.

On the other hand, in order to manufacture a wiring board at low cost by forming a circuit without plating, as shown in FIG. 2, the wall of the hole drilled with silver or copper paste containing the metal particles, the binder and the solvent is formed. Coating or forming a circuit from the paste known per se has been performed for a long time.

Among the above methods for the manufacture of wiring boards, the plating method has been used for the manufacture of wiring boards with high connection reliability.

Along with the proliferation of electrical electronics, there is a strong demand for providing high performance electronics at low cost.

In the above methods for producing wiring boards using plating, a fairly large apparatus is required because the plating time cannot be shorter than now and a specific apparatus for plating is required and the plating solution must be controlled.

That is, in the present situation, the efficiency of wiring board manufacturing is limited as long as plating is used.

In a method for manufacturing a wiring board at low cost, as shown in FIG. 2, the conductive paste cannot completely fill the inside of the drilled hole, the connection area is small, the connection resist is large, and consequently, such as a multi-sided circuit board or both circuit boards. Only a wiring board of low wiring density is obtained.

In the above method of applying the conductive paste by printing, it is impossible to form a complicated circuit and the connection reliability is too low to produce a multilayer wiring board. Therefore, it is difficult to manufacture high performance wiring boards using low cost materials.

It is an object of the present invention to provide a low cost printed wiring board having a high wiring density and a method for efficiently manufacturing the wiring board.

The present invention includes an insulating layer and a metal thin film layer formed on both sides of the insulating layer, wherein the metal thin film layer has one or more recesses through which holes are formed, and the recess portion provides a wiring board for an inner layer circuit filled with a conductor.

The present invention also has a metal thin film layer formed on both sides of the insulating layer and the insulating layer and one or more holes formed through the insulating layer and the metal thin film layer, the narrow portion is concave around each hole in the metal thin film layer, the recesses and holes It is to provide a wiring board filled with a conductive material.

The present invention also includes an outer circuit layer formed of metal on both sides of the inner layer circuit board through at least one inner layer circuit board and a prepreg, wherein the inner layer circuit board includes an insulating layer and a metal thin film layer formed on both sides of the insulating layer. The at least one inner circuit board or the outer circuit layer or both have recesses filled with a conductive material in a metal thin film layer, wherein the wiring boards are at least in recesses and have at least one through hole filled with a conductive material. A method for producing these wiring boards is provided.

The wiring board of the present invention includes an insulating layer and a metal thin film layer formed on both sides of the insulating layer, wherein the metal thin film layer has one or more recesses through which holes are formed, and the recess is filled with a conductor, and the metal thin film is a copper thin film, Or a composite metal thin film including a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions.

The wiring board of the present invention also has an insulating layer and a metal thin film layer formed on both sides of the insulating layer, wherein the metal thin film layer has one or more holes penetrating the insulating layer and the metal thin film layer, and is narrow in two holes in the metal thin film layer. The concave portion and the hole are filled with a conductive material, and the metal thin film is a copper thin film or a composite metal thin film including a core metal layer and a copper layer formed on one side or both sides of the core metal layer. The copper layer has different chemical removal conditions, and the recess is formed in either the core metal layer or the core layer.

The wiring board of the present invention also has an outer circuit layer formed of metal on both sides of the inner layer circuit board through at least one inner layer circuit board and a prepreg, wherein the inner layer circuit board has an insulating layer and a metal thin film layer formed on both sides of the insulating layer. And at least one inner layer circuit board or the outer circuit layer or both have a recess filled with a metal thin film conductive material, the wiring board has at least one through hole filled with a conductive material, the metal The thin film is a copper thin film or a composite metal thin film including a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions, and the concave portion is the core metal layer or the It is formed in one of the core layers.

In this case, one of the outer circuit layers may be omitted, and the outermost inner circuit may serve as an omitted outer circuit layer.

The wiring board of the present invention can be manufactured by various methods.

For example, a wiring board may be heat bonded by laminating a pair of metal thin films, one on each side of an insulated substrate that is not completely cured, and drilling one or more holes necessary for circuit contact of the laminate, in a narrow area around the hole. Removing the metal thin film to form a recess in the metal thin film, and filling the hole and the recess with a fluid conductive material, wherein the metal thin film is a copper thin film, or one side of the core metal layer and the core metal layer. Or a composite metal foil including copper layers formed on both sides, wherein the core metal layer and the copper layer have different chemical removal conditions, and the recess is formed only in one of the core metal layer or the core layer.

The recess may be formed in the metal thin film at the portion where the hole is to be drilled before the hole is drilled.

The wiring board also includes a step of laminating the pre-cracks and the metal thin films on both sides of the one or more inner layer circuit boards, drilling one or more holes necessary for connecting the circuits to the laminate, and removing the metal thin films from the narrow area around the holes. To form a recess in the metal thin film, and to fill the hole and the recess with a fluid conductive material, wherein the metal thin film is a copper thin film or a core metal layer and a copper layer formed on one side or both sides of the core metal layer. It is a composite metal thin film comprising a, wherein the core metal layer and the copper layer is different chemical removal conditions, the concave portion is formed only in the core metal layer or copper layer.

In the above-described method, the recess may be formed in the metal thin film at the portion where the hole is to be drilled before the hole is drilled.

The methods described above include the steps of curing the flowable conductive material, removing the protrusions of the conductive material higher than the peripheral height, applying the surface portion with the resist to form a circuit conductor including the cured conductive material, from the resist It may also include removing the exposed portion by etching to form an outer layer circuit.

The wiring board may also be formed by laminating a pair of metal thin films, one on each side of an insulated substrate, which is not completely cured, and hot pressing them, drilling holes necessary for circuit connection to the laminate, and removing metal thin films from the narrow area around the holes. Forming recesses in the thin metal film, filling the holes and recesses with the fluid conductive material to cure, removing protrusions of the conductive material higher than the peripheral height, and forming a circuit conductor including the cured conductive material. Coating the surface portion with a resist, removing the exposed portion from the resist by etching to form an inner layer circuit board, and laminating and preheating prepreg and metal films on both sides of the one or more inner layer circuit boards thus produced. Drilling at least one hole in the stack required for circuit connection, on the inner wall of the hole Forming a metal layer by plating, applying an external metal thin film necessary for forming a circuit with a resist, and removing an unnecessary metal thin film by etching to form an external circuit layer, and forming an inner layer. In the manufacture of the circuit board, the drilling step may be omitted, and the metal thin film is a composite metal thin film including a copper thin film or a core metal layer and a copper layer formed on one or both sides of the core metal layer, and the core metal layer and the copper layer are chemically The removal conditions are different, and the recess is formed only in the core metal layer or the copper layer.

The wiring board is also laminated with a pair of thin metal films, one on each side of the insulated substrate, which is not fully cured, and one or more holes necessary for connecting the circuits to the laminate are formed. Forming a recess in the metal thin film, filling the hole and the recess with a fluid conductive material, and hardening, removing a protrusion of the conductive material higher than the peripheral height, and forming a circuit conductor including the cured conductive material. Applying the surface portion required to the resist, removing the exposed portion from the resist by etching to form an inner layer circuit board, and laminating and heating prepreg and metal thin films on both sides of the one or more inner layer circuit boards thus produced. Squeezing, drilling one or more holes necessary for circuit connection in the laminate, The hole may have a diameter smaller than that of a hole drilled in an inner layer circuit board, the metal thin film may be removed from the narrow region around the hole to form a recess in the metal thin film, and the fluid conductive material may be filled in the hole and the recess. In the inner layer circuit board manufacturing, the perforation step may be omitted, and the metal thin film is a composite metal thin film including a copper thin film or a core metal layer and one side view of the core metal layer. The metal layer and the copper layer differ in chemical removal conditions, and the recess is formed only in the core metal layer or the copper layer.

The methods described above include the steps of curing the flowable conductive material, removing the protrusions of the conductive material higher than the peripheral height, applying a surface portion with the resist to form a circuit conductor including the cured conductive material, and removing the resist from the resist. It may also include the step of removing the exposed portion by etching to form an inner layer circuit board, the perforation step may be omitted in the manufacture of the inner layer circuit board, the metal thin film is a copper thin film or core metal layer and one side of the core metal layer or A composite metal thin film including a copper layer formed on both sides, wherein the core metal layer and the copper layer are different in chemical conditions, and the recess is formed only in the core metal layer or the copper layer.

The wiring board of the present invention is, for example, an insulated substrate or an inner layer circuit board having holes formed therein as shown in FIG. 1A, and as a conductor land formed on at least one side of the substrate such that each land surrounds each hole opening. Each land portion adjacent to each of the hole inlets includes a conductor land that is concave compared to the rest of each land portion to form a metal recess, and a conductive material filling each hole and each metal recess. The top view of the wiring board which respectively has the said structure is shown.

When the fluid conductive material is filled in each hole and each metal recess as shown in 1a, the wiring board manufacturing method does not require any plating step and is efficient.

As shown in Figs. 5A to 5E, the above-mentioned method of the present invention for producing a wiring board includes the steps of placing a copper thin film on each side of an insulated substrate that is not completely cured, and heating them under pressure to form a laminate. Step (shown in FIG. 5A), drilling holes for the connection of the circuit layer in the required portion of the stack (shown in FIG. 5B), and each hole (see FIG. 5C) within a range where the insulating substrate is not exposed. Removing only the copper thin film portion in the narrow region around each hole inlet (or opening), and filling the fluid conductive material with each hole and each metal recess to form a metal recess around the inlet. It includes (shown in Figure 5D).

The method also includes laying a thin copper film on at least one side of a laminate obtained by placing a prepreg on at least one side of one inner circuit board or a plurality of inner circuit boards, under pressure to form the laminate. Heating a hole, drilling a circuit layer connection hole in a required portion of the laminate, and forming copper recesses around each hole inlet in the range where the prepreg is not exposed; Removing only the thin film portion, and filling the hole and each metal recess in the fluid conductive material.

The method also includes a core metal layer and one or two copper layers formed on either side or one side of the core metal layer on each side of the insulated substrate that is not fully cured, wherein the core metal layer and the copper layer have two or three different chemical removal conditions. Laying a thin metal film, which is a stack of two metal layers, heating them under pressure to form a stack, drilling holes for connecting circuit layers in the required portions of the stack, forming metal recesses around each opening To this end, it may include removing only each copper layer portion around each hole inlet, and also filling the fluid conductive material in each hole and each metal recess.

The method also includes one or two copper formed on at least one side of the core metal layer and the core metal layer and on at least one side of the laminate obtained by placing the prepreg on at least one side of one inner circuit board or a plurality of inner circuit boards. Laying down a metal thin film comprising a layer, the core metal layer and the copper layer being a stack of two or three metal layers having different chemical removal conditions, heating them under pressure to form the laminate, the required location of the laminate Drilling holes for circuit layer connection, removing each copper layer portion around each hole entrance, and filling a fluid conductive material in each hole and each metal recess to form metal recesses around each hole inlet. It may also comprise the step.

The method also includes placing a copper thin film on each side of the insulated substrate that is not fully cured, heating them under pressure to form a laminate, and opening the circuit connection holes within the range where the insulated substrate is not exposed. Removing only a portion of each copper foil of the laminate (the diameter of each of the portions is slightly larger than the diameter of each hole to be drilled) to form a metal recess around each hole opening to be drilled, preferably at the center of each metal recess And drilling the flowable conductive material in each hole and each metal recess. The method also includes at least one side of the laminate obtained by placing a prepreg on at least one side of the inner circuit board. Laying the copper thin film, heating them under pressure to form a laminate, the prepreg is not exposed Within the range, removing only the portions of each copper thin film of the laminate to which the circuit layer connection holes are to be drilled (the diameter of each said portion is slightly larger than the diameter of each hole to be drilled) to form a metal recess around each hole opening to be drilled. And, preferably, drilling the hole at the center of each metal recess, and filling a fluid conductive material in each hole and each metal recess. The method may also include angular positioning of an insulated substrate that is not fully cured. Laying a metal thin film comprising a core metal layer and one or two copper layers formed on both or one side of the core metal layer, wherein the core metal layer and the copper layer are laminates of two or three metal layers having different chemical removal conditions. Heating them under pressure to form a portion of each copper layer of the laminate to be perforated for circuit layer connection (each said portion) The diameter of the hole is slightly larger than the diameter of each hole to be drilled) to form a metal recess in each opening of the hole to be drilled, preferably drilling the recess at the center of the metal recess, and each hole and each hole and metal And filling the recess with the fluid conductive material.

The method also includes a core metal layer and one or two copper layers formed on either or both sides of the core metal layer and the core metal layer on at least one side of the laminate obtained by placing the prepreg on at least one side of the inner circuit board, wherein the core metal layer and the copper layer are Laying a metal thin film, which is a laminate of two or three metal layers having different chemical removal conditions, heating them under pressure to form a laminate, and a portion of each copper layer of the laminate to be perforated for circuit layer connection ( Removing only the diameter of each hole to be drilled) to form a metal recess around each hole inlet to be drilled, preferably drilling the hole at the center of each metal recess, and each metal recess And filling the fluid conductive material in each hole.

As shown in FIG. 5E, the present method fills the fluid conductive material 3 with each hole and each metal recess, and then hardens the conductive material 3 to the surface of the non-concave portion of each copper thin film. Removing each portion of the conductive material 3 protruding from the plane (i.e., the surrounding height) formed by the resist, and applying a resist on the portion of the angle body (copper thin film) required for circuit formation, including a recess filled with the conductive material. Forming, and also removing the exposed (resist-free) portion of the angler by etching to obtain a wiring board.

The method also includes placing a thin copper film on each side of the insulated substrate that has not been fully cured, heating them under pressure to form a laminate, and drilling holes for circuit layer connections at the desired locations of the laminate. Removing the portions of each of the copper thin films of the laminate around the inlet of each hole, so as not to expose the insulating substrate, thereby forming metal recesses around the inlet of each hole; fluidity in each hole and each metal recess. Filling the conductive material, curing the flowable conductive material, removing each portion of the conductive material protruding from the plane formed by the surface of each copper thin film, and including recesses filled with the conductive material. Forming a resist on the portion of the angle body (copper thin film), exposing the angle body by etching to form an inner circuit board (without resist A) removing the part, placing the prepreg and copper thin film on at least one side of the inner layer circuit board, heating under pressure to form the laminate, drilling a connection hole at the required position of the laminate, plating Forming a metal layer on the wall of each hole, forming a resist on a portion of each copper thin film (outermost layer) which will constitute the circuit, and exposing each copper thin film by etching to obtain a multilayer wiring board ( It may also include removing the portion without the resist.

The method also includes one or two copper layers formed on either side or one side of the core metal layer and the core metal layer on each side of the insulated substrate that is not fully cured, wherein the core metal layer and the copper layer have two or three different chemical removal conditions. Step of laying the metal thin film, which is a stack of metal layers, heating them under pressure to make a stack, making holes for circuit contact at the required positions of the stack, and only a portion of each copper layer at each opening of each hole. Removing to form metal recesses around each hole inlet, filling each hole and each metal recess with a fluid conductive material, curing the fluid conductive material, a plane formed by the surface of the non-concave portion of each copper thin film Removing each portion of the conductive material protruding from the filler, comprising a recess filled with the conductive material Forming a resist on a portion of the required angler (copper thin film), removing an exposed (resistless) portion of the angler by etching to form an innerlayer circuit board, prepreg and copper on one side of the innerlayer circuit board Laying a thin film, heating them under pressure to form a laminate, drilling holes for contacting the arc layer at the required position of the laminate, forming a metal layer on the walls of each hole by plating, and Forming a resist on a portion of each copper layer (outermost layer) constituting the film; and removing the exposed (resist-free) portion of each copper thin film by etching.

As shown in FIGS. 7A-7G, the method also includes placing copper thin films 2 on each side of the insulated substrate 1 that is not fully cured, heating them under pressure to form a laminate. (Shown in FIG. 7A), the step of drilling a circuit connection hole at a required position of the laminate, and removing only each copper thin film portion of the laminate around each hole inlet within the range where the insulating substrate 1 is not exposed. Forming a metal recess around each hole inlet (shown in FIG. 7B), filling each hole and each metal recess in the fluid conductive material 3, curing the fluid conductive material 3, Angles necessary for circuit formation, including steps (shown in FIG. 7C) for removing the respective portions of the conductive film 3 protruding from the plane formed by the surface of the non-concave portion of each copper thin film, and recesses filled with the conductive material. Regis on part of (copper film) Forming an inner layer circuit board by removing the exposed (resistless) portions of the angled bodies due to etching (shown in FIG. 7D), and forming a prepreg 5 and a copper thin film on at least one side of the inner layer substrate. 21, the step of heating them under pressure to form a laminate (shown in FIG. 7e), through the hole in the inner layer circuit board filled with the perforated conductive material 3 in the laminate ( That is, the hole diameter of the former is smaller than the hole diameter of the latter) at least one hole is drilled (shown in FIG. 7F) to enable the connection between the inner layer circuit and the outer layer circuit, and the prepreg 5 is exposed. Within the range not to be removed, only a portion of the copper thin film 21 is removed at each of the two hole inlets opened above to form metal recesses around each hole inlet, and the fluid conductive material 31 is formed in each hole and each metal recess. Charging) The invention may also include placing a thin copper film on each side of an insulated substrate that is not fully cured, heating them under pressure to form a laminate, and requiring the laminate. Punching a circuit connection hole at a position to be formed, removing a portion of each copper thin film of the laminate around each hole inlet, and forming metal recesses in each of the hole inlets, within a range where the insulating substrate is not exposed; Filling each hole and each metal recess with a fluid conductive material, curing the fluid conductive material, removing each portion of the conductive material protruding from the plane formed by the surface of the non-concave portion of each copper thin film, conductive Forming a resist on a portion of the angler (copper thin film) required for circuit formation, including a refilled recess, the exposed (resin of the angler by etching) Forming an innerlayer circuit board by removing only the unheated portion, the core metal layer and the copper layer comprising at least one side of the inner layer circuit board, the prepreg and the core metal layer and one or two copper layers formed on both sides or one side of the core metal layer. Laying a metal thin film, which is a laminate of two or three metal layers with different chemical removal conditions, heating them under pressure to form a laminate, an inner layer circuit board filled with a porous conductive material 3 in the laminate Drilling at least one hole through one hole of the hole (ie, the hole diameter of the former is smaller than the hole diameter of the latter) to enable connection between the inner layer circuit and the outer layer circuit, stacking each hole entrance Removing only portions of each copper layer of the sieve to form metal recesses around each hole inlet, each hole and metal recess Filling the dynamic conductive material, curing the fluid conductive material, removing each portion of the conductive material protruding from the plane formed by the non-concave surface of each outermost copper layer, and including a recess filled with the conductive material Forming a resist on a portion of the angler (outermost copper layer) required for circuit formation, and removing the exposed (resistless) portion of the angler by etching.

The method includes one or two copper layers formed on both sides or one side of the core metal layer and the core metal layer on each side of the insulated substrate, which is not completely cured, so that the core metal layer and the copper layer have two or three metal layers with different chemical removal conditions. Laying a thin metal film, which is a stack of layers, heating them under pressure to form a stack, removing only a portion of each copper or core metal layer of the stack around each hole inlet, thereby forming a metal recess in each of the two hole inlets. Filling the fluid conductive material into the holes to be formed, the holes and the metal recesses, the steps to cure the fluid conductive material, and each part of the conductive material protruding from the plane formed by the non-concave surface of each copper or core metal layer. Removing the angle of the angle body (copper or core metal layer) required for circuit formation, including a recess filled with a conductive material. Forming a resist on the substrate, removing an exposed (resistless) portion of the angler by etching to form an inner circuit board, placing a prepreg and a thin copper film on at least one side of the inner circuit board, Heating them under input to form a stack, in which the stack passes through a hole in an inner circuit board filled with a hole conducting material (i.e., the hole diameter of the former is smaller than the diameter of the latter) And drilling at least one hole to enable connection between the outer layer circuits, removing the portion of the copper foil around each of the openings and removing the metal at each of the inlet openings, within the extent that the prepreg is not exposed. Forming recesses and filling each hole and each metal recess conductive material.

The method includes a core metal layer and one or two copper layers formed on both sides or one side of the core metal layer on each side of an insulated substrate that is not completely cured, and the core metal layer and the two or three metal layers having different chemical removal conditions. Laying a thin metal film, which is a stack of layers, heating under pressure to form a stack, drilling holes for connecting the circuit layers in the required position of the stack, each copper or core of the stack around each opening inlet Removing the metal layer to form metal recesses around each hole inlet, forming each hole and each metal recess, filling each hole and each metal recess with a fluid conductive material, and curing the fluid conductive material. Each part of the conductive material protruding from the plane formed by the surface of each non-concave portion of each copper or core metal layer Forming a resist on a portion of the angler (copper or core metal layer) necessary for forming a circuit comprising a recess filled with a conductive material, removing the exposed (resistless) portion of the angler by etching the inner layer Forming a circuit board, placing a prepreg and a metal thin film as described above on at least one side of the inner layer circuit board, heating them under pressure to form a laminate, in the laminate, as a pore conducting material Drilling at least one hole through one hole of the filled inner layer circuit board (ie, the former hole diameter is smaller than the latter hole diameter) to enable connection between the inner layer circuit and the outer layer circuit, each hole Removing only portions of each copper layer of the laminate around the inlet to form metal recesses around each aperture, each hole and each metal recess Filling the flowable conductive material, curing the flowable conductive material, removing each portion of the conductive material protruding from the plane formed by the surface of each outermost copper layer, the circuit comprising a portion filled with the conductive material Forming a resist on the portion of the angler (outermost copper thin film) required for formation, and removing the protruding (resistless) portion of the angler by etching.

The present invention is directed to placing a copper thin film on each side of an insulated substrate that has not been completely cured, heating them under pressure to form a laminate, and openings for circuit layer connections within the range where the insulating substrate is not exposed. Removing only the copper thin film portions of the laminate (the diameter of each of the portions is slightly larger than the diameter of each hole to be drilled) to form metal recesses around each opening of the drilled holes, and filling the fluid conductive material into each metal recess. Step, curing the fluid conductive material, removing each portion of the conductive material protruding from the plane formed by the non-concave surface of each copper layer, each copper required for circuit formation, including a recess filled with the conductive material Forming a resist over a portion of the layer, removing a portion of the copper layer (resistless) exposed by etching to form an innerlayer circuit board, Placing a prepreg and a copper thin film on at least one side of the inner layer circuit board, heating under pressure to form a laminate, drilling holes for connecting the circuit layer at the required positions of the laminate, and plating each hole. Forming a metal layer on the wall, forming a resist on a portion of each outermost copper layer to be a circuit, and removing an exposed (resistless) portion of each outermost copper layer by etching. The method comprises two or more core metal layers and copper layers having different chemical removal conditions, including one or two copper layers formed on both sides or one side of the core metal layer and the core metal layer on both sides of the insulated substrate that are not fully cured. Laying a thin metal film, which is a stack of three metal layers, heating them under input to form a stack, circuit layer Removing only the copper layer portions (each diameter of the portion is slightly larger than the diameter of each hole to be drilled) of the laminate to be pierced to form a metal recess around each hole inlet to be drilled, the fluidity of each metal recess Filling the electrode, curing the fluid conductive material, removing each portion of the conductive material protruding from the plane formed by the surface of the non-concave portion of each copper layer, forming a circuit comprising a recess filled with the conductive material Forming a resist on each copper layer portion necessary for forming a layer, removing the exposed (resistless) copper layer portion by etching to form an inner layer circuit board, and placing a copper thin film and prepreg on at least one side of the inner layer circuit board. Step, heating them under pressure to form a laminate, drilling holes for circuit layer connections in the required position of the laminate Forming a metal layer on the wall of each hole by plating, forming a resist on a portion of each outermost copper layer of the laminate to be a circuit, and exposing each outermost copper layer by etching (resistless ) May be removed.

As shown in Figs. 6A to 6F, the method includes placing a thin copper film 2 on each side of an insulated substrate 1 that is not fully cured, heating them under pressure to form a laminate ( 6A), each copper thin film of the laminate in which the circuit layer connection holes are to be drilled (the diameter of each of the portions is slightly larger than the diameter of each hole to be drilled) within the range that the insulating substrate 1 is not exposed. 2) forming only a metal recess in each hole inlet hole to be removed by only removing the portion, filling the fluid conductive material 3 with each metal recess (shown in FIG. 6B), and curing the fluid conductive material 3 However, the steps of removing the respective portions of the conductive material 3 protruding from the plane formed by the non-concave surface of each copper layer, comprising a recess filled with the conductive material, an angle body (copper thin film) required for circuit formation Forming a resist over a portion of Removing the portion of the conductor (resistless) exposed by the to form an inner circuit board (shown in FIG. 6c), placing the prepreg 5 and the copper thin film 21 on at least one side of the inner circuit board, Heating under pressure to form a laminate, through which the laminate passes through a recess of the inner circuit board filled with the perforated conductive material 3 (ie, the diameter of the hole is smaller than the diameter of the recess) And drilling at least one hole to enable the connection between the outer layer circuits, and within the range in which the prepreg 5 is not exposed, a portion of each copper thin film 21 around each of the perforated hole openings. Removing to form a metal recess around each hole inlet (shown in FIG. 6D), and filling a fluid conductive material in each hole and each metal recess (shown in FIG. 6E).

The method comprises the steps of: placing a thin copper film on each side of an insulated substrate that is not fully cured, heating them under pressure to form a laminate, and openings for circuit layer connections within a range where the insulated substrate is not exposed. Removing only the copper thin film portions of each laminate to be drilled (the diameter of each portion is slightly larger than the diameter of each hole to be drilled) to form metal recesses around each opening of the holes to be drilled, and filling the fluid conductive material with each metal recess. Removing the portions of the conductive material protruding from the plane formed by the surface of the non-concave portion of each copper layer, including the recesses filled with the conductive material. Forming a resist over a portion of the copper layer, removing the portion of the copper layer exposed by etching (resistless) to form an inner circuit board, On at least one side of the layer circuit board, the core metal layer and the copper layer are laminates of two or three metal layers having different chemical removal conditions, including a prepreg and a core metal layer and one or two copper layers formed on both or one side of the core metal layer. Laying a thin metal film, heating them under pressure to form a laminate, through the recess a hole in an inner circuit board filled with a conductive material (i.e., the hole diameter is the recess diameter Smaller) drilling at least one hole to enable connection between the inner layer circuit and the outer layer circuit, removing only the outermost copper layer portion around each hole opening to form a metal recess around each hole opening The step of filling the fluid conductive material in each hole and each metal recess, the step of curing the fluid conductive material Removing each portion of the conductive material protruding from the plane formed by the non-concave surface of each outermost copper layer, including the portion filled with the conductive material.

The method may include forming a resist on a portion of the angler (copper thin film) required for circuit formation, and removing the exposed (resistless) portion of the angler by etching.

The method includes a core metal layer and one or two copper layers formed on both sides or one side of the core metal layer on both sides of the uncured insulating substrate, wherein the core metal layer and the copper layer are formed of two or three metal layers having different chemical removal conditions. Laying a metal thin film, which is a laminate, heating them under pressure to form a laminate, each copper layer of the laminate to which holes for circuit layer connection are to be drilled (each diameter of the portion is slightly larger than the diameter of each hole to be drilled). Or removing only the core metal layer portion to form metal recesses in each of the two hole inlets to be drilled, filling the fluid conductive material in each metal recess, curing the fluid conductive material, ratio of each copper layer or core metal layer Removing each part of the conductive material protruding from the plane formed by the surface of the recessed portion, the recessed portion filled in the conductive material Forming a resist over an angled (copper layer or core metal layer) portion necessary for forming the circuit, removing the exposed (resistless) copper layer portion to form an inner layer circuit board, Placing the copper thin film and the propreg on at least one side, heating them under pressure to form a laminate, in the laminate, through a recess in the inner layer circuit board filled with the conductive material (i.e., the hole) A diameter of which is smaller than the diameter of the recess) drilling at least one hole to enable connection between the inner layer circuit and the outer layer circuit, within a range in which the prepreg is not exposed, the laminate around each of the drilled holes Removing each copper thin film portion of the to form a metal recess around each hole inlet, each hole and each metal recess The fluid may also comprise the step of charging the reproduction.

The present invention includes a core metal layer and one or two copper layers formed on both sides or one side of the core metal layer on each side of the insulated substrate which is not completely cured, and the core metal layer and the two or three metal layers having different chemical removal conditions. Laying a thin metal film, which is a stack of layers, heating under pressure to form a stack, each copper layer of the stack to which holes for circuit layer connection are to be drilled (each diameter of the portion is slightly larger than the diameter of each hole to be drilled) or Removing only the core metal layer portion to form metal recesses around each hole inlet to be drilled, filling each metal recess with a fluid conductive material, curing the fluid conductive material, and a non-concave portion of each copper layer or core metal layer Removing each portion of the conductive material protruding from the plane formed by the surface, the recess being filled with the conductive material Forming a resist on an angle body (copper layer or core metal layer) portion necessary for circuit formation, removing an exposed (resistless) conductor portion to form an inner circuit board, and at least one side of the inner circuit board. Laying metal thin films and prepregs as described above, heating them under pressure to form a laminate, through the recesses through one recess of an inner layer circuit board filled with a conductive material (i.e., The hole diameter is smaller than the diameter of the recess) drilling at least one hole to enable connection between the inner layer circuit and the outer layer circuit, the portion of the core metal layer or copper layer in the laminate around each of the perforated hole openings. Removing the bays to form metal recesses around each of the openings of the holes, filling each hole and each metal recess with a fluid conductive material Curing the fluid conductive material, removing each portion of the conductive material protruding from the plane formed by the surface of the non-concave portion of each core metal layer or copper layer, and including a recess filled with the conductive material. Forming a resist on a portion of the required angler (copper or core metal layer) and may also include removing the exposed (resistless) portion of the conductor.

As shown in FIG. 6F or 7H, the method includes, after filling the fluid conductive material 31 in each hole and each metal recess, curing the fluid conductive material 31, each outermost angle. Removing each portion of the cured conductive material 31 protruding from the plane formed by the surface of the non-concave portion of the metal layer, the angle body (outermost metal layer) required for circuit formation, including a recess filled with the conductive material. Forming a resist on the portion, and removing the exposed (resistless) portion of the angled body by etching to obtain a multilayer wiring board.

1 to 7, reference numeral 1 denotes an insulating layer, numeral 2 denotes a copper thin film, numeral 3 denotes a conductive material, numeral 4 denotes wiring, and numeral 5 denotes a prepreg. Reference numeral 21 denotes a copper thin film, and reference numeral 31 denotes a conductive material.

In the present invention, as the insulating substrate that is not completely cured, those impregnated with reinforcing fibers (for example, glass forge) with an epoxy resin or a phenol resin may be used. Also, a solubility such as a polyester film or a polyimide film may be used. Insulating substrates obtained by applying an adhesive on the surface of the insulating film can be used. The use of the insulating film can reduce the overall thickness of the obtained insulating substrate, and can also be used as a cable for connecting a portion of the insulating film to another circuit. It is preferable because there is.

The metal thin film may be a composite metal thin film or a copper thin film including a copper layer and a core metal layer formed on one side or both sides of the core metal layer. When a copper thin film is used, the thickness is preferably 20 to 70 μm. If it is small, the control of etching to form the recess becomes difficult, whereas if the thickness is larger than 70 mu m, the formation of precise wiring becomes difficult due to the increased side etching.

In the case of using a two-layer composite metal thin film comprising a core layer and a copper thin film, the thickness of the layer in contact with the insulating substrate is preferably 1 to 15 µm, and the thickness of the layer remaining as the circuit conductor is preferably 20 to 70 μm. As the core layer, a layer of nickel, nickel phosphorus alloy, nickel boron alloy or solder can be used. The core metal and copper layer must have different chemical removal conditions, i.e., etching conditions. Has a recess so that the remaining layer (copper layer or core metal layer) contacts the insulating substrate, while only the metal (core metal or copper) is removed by chemically different removal conditions. While the upper layer must have the thickness necessary to form a wall that impedes the flow of the conductive material to parts other than the circuit as the lower limit, it is necessary to contact the conductive material. It must have a minimum thickness.

In the case of using a three-layer composite metal layer in which the core layer is sandwiched by a copper layer, the copper layer not in contact with the insulating substrate on the core metal layer corresponds to the layer not in contact with the insulation layer in the case of a two-layer composite metal thin film. do.

As described above, the layer preferably has a thickness of 20 μm or more to hinder the flow of the external conductive material of the circuit when the recess is filled, and preferably a thickness of 70 μm or less for the correct operation of the circuit. The remaining copper layer in contact with the insulating substrate has a thickness of 1 to 15 [mu] m for the same reasons as mentioned above. The core metal layer is used as an intermediate layer serving as a barrier when the copper of the recess is removed by etching. .

The core metal layer is made as thin as possible.

The preferred thickness is 0.05 to 2 [mu] m. If the thickness is too thin, the role as a barrier is lost. The total thickness of the core metal layer and the copper layer in contact with the insulating substrate is preferably in contact with the insulating layer in the case of a two-layer composite metal layer. Concave portions can be formed without controlling the amount of the etched metal thin film.

The diameter of the concave portion formed in the metal thin film is preferably the size of the hole diameter plus 0.1 to 0.6 mm, or more preferably the diameter of the hole plus 0.2 to 0.4 mm. If the diameter is smaller than the hole diameter + 0.1 mm, The contact area between the conductive material and the circuit conductor becomes smaller, and the design becomes difficult due to the working error considering the resist plate and the hole position. On the other hand, when the diameter is larger than the diameter of the hole plus 0.6 mm, the connection hole The molten region becomes too large, making it difficult to form another wiring.

As the conductive material, a mixture containing conventionally used silver paste, metal particles such as copper paste, a binder and a solvent can be used. In this mixture, when heat is applied, the solvent is evaporated to strengthen the binder, whereby the metal particles solidify. do.

As a conductive material, a mixture of particles of low melting point metal (e.g. solder) and a solvent (the mixture is filled in each hole and each recess surrounding the hole and then heated to evaporate the solvent to dissolve the metal particles). , Followed by cooling for solidification of the metal), the contact resistance can be made small.

The mixture of particles of low melting point metal (e.g. solder) and the solvent is filled in each hole and each recess surrounding the hole and then heated to evaporate the solvent to melt the metal particles, followed by cooling for solidification of the metal. This can be done by pressing an adaptation comprising a metal plate, a heat resistant film placed thereon and a mixture coated on the heat resistant film, in order to prevent the flow of solder.

In the wiring board of the present invention, as shown in FIGS. 1A and 1B, the land has a special structure to give high connection reliability even when the conductive material is filled in the hole. The structure gives a larger connection area, It is also suitable for use in multilayer wiring boards because it provides a flat surface even after charging.

Example 1

MCL-E-67 (trade name) manufactured by Hitachi Chemical Co., Ltd., by placing a 35 μm thick copper thin film on each side of a glass cloth-epoxy resin insulated substrate and heating them under pressure The hole for the circuit layer connection was drilled at the required position of the laminate. An etching resist was formed on the laminate so that the copper thin film portion and the hole around the hole inlet were exposed. Based on the relationship between time and remaining copper thin film thickness, the exposed (resistless) copper thin film portion is removed to ensure that the remaining copper thin film is about 2 [mu] m thick, with metal recesses around each hole opening. The etching resist was removed by peeling and the silver paste was filled in each hole and each recess by screen printing.

The filled silver paste was cured in a conveyor type dryer. As with the silver paste adhered on the copper thin film surface, each portion of the silver paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. The resist was included in the circuit formation, including the recesses filled with the silver paste. It formed on the part of the required angle body (copper thin film). The exposed (resistless) conductor part was removed by etching, and the wiring board was obtained.

Example 2

The laminate [MCL-E 67 (trade name) manufactured by Hitachi Chemical Co., Ltd.] is etched to remove unnecessary portions of each copper layer of the laminate to form an inner circuit board. A prepreg is formed on each side of the inner circuit board [ GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd. was manufactured. A copper thin film having a thickness of 35 μm was also placed on each prepreg. The holes for connecting the circuit layers were drilled at required positions of the laminate. An etching resist is formed on the laminate in order to expose portions of the copper thin film around the hole and the hole opening. Based on the relationship between the time taken for etching and the remaining thickness of the copper thin film obtained previously, the exposed (resist free) The copper thin film portion was removed so that the thickness of the remaining copper thin film was about 5 mu m, whereby a metal recess was formed around each hole inlet. The etching resist was removed by peeling, and the silver paste was filled in each hole and each recess by screen printing.

The filled silver paste was cured in a conveyor type dryer. As with the silver paste adhered on the copper thin film surface, each portion of the silver paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. (2) A portion of the angled body (copper thin film) required for circuit formation was formed, including a recessed portion filled with silver paste. [0050] The exposed (resistless) conductor portion was removed by etching to obtain a wiring board.

Example 3

3 containing two copper layers formed on both sides of the core nickel layer and the core nickel layer on each side of the prepreg, which is a glass cloth-epoxy resin insulated substrate [GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.). The metal thin film, which is a layered laminate, was placed. They were heated under pressure to form a laminate. Only the portion of the laminate in which the etching resist was perforated for the circuit layer connection (the diameter of each portion was slightly larger than the diameter of each hole to be drilled). Formed on the stack to be exposed. Each hole to be drilled by removing only the copper layer of each exposed (resistless) laminate portion using an alkaline etchant comprising tetraminine (II), salt, ammonium chloride and ammonia. Metal recesses were formed around the inlet.

Holes were drilled in each recess. Copper paste was filled in each hole and each recess by screen printing.

The filled copper paste was cured in a conveyor-type drier. As with the copper paste adhered on the copper thin film surface, each portion of the copper paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. Was formed on a portion of each conductor (copper thin film) required for circuit formation, including a recess filled with a copper paste. The exposed (resistless) conductor portion was removed by etching to obtain a wiring board.

Example 4

The laminate [GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.] was etched to remove unnecessary portions of each copper layer of the laminate to form an inner layer circuit board. A prepreg was formed on each side of the inner layer circuit board. GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd. was placed. On each prepreg, a core metal layer (made of nickel phosphorus alloy) and two copper layers formed on both sides of the core metal layer by electroless plating were placed. A metal thin film is placed on the containing three-layer laminate. They are heated under pressure to form a laminate. The etching resist is a portion of the laminate in which the circuit layer connection holes are made (the diameter of each portion is larger than the diameter of each hole to be drilled). Slightly larger) was formed on the laminate so as to expose only the copper layer of each exposed (resistless) laminate portion tetraminecopper (II), salt, chloride rock. Alkali etching solution containing monium and ammonia was used to form metal recesses around the openings of each hole to be removed. Holes were drilled in each recess. Copper paste was filled in each hole and each recess by screen printing. .

The filled copper paste was cured in a conveyor type dryer. As with the silver paste adhered on the copper foil surface, each part of the paste protruding from the plane formed by the non-concave portion of each copper foil was removed using a grinder. And formed over a portion of an angle body (copper thin film) necessary for circuit formation, including a recess filled with a copper paste. The exposed (resistless) conductor portion was removed by etching to obtain a wiring board.

Example 5

On each side of the inner circuit board as used in Example 1, prepreg (GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.) and a copper thin film having a thickness of 35 µm were placed. The hole for circuit layer connection was drilled at the required position of the laminate. The laminate was subjected to pretreatment, sensitization treatment, and electroless plating treatment for plating and seeding, to A metal layer was formed on the wall. A resist was formed on the portion of the outermost copper layer to be a circuit. The outermost copper layer of the exposed (resistless) portion was removed by etching to obtain a wiring board.

Example 6

On each side of the inner circuit board as used in Example 2 was placed a prepreg (GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.) and a copper thin film having a thickness of 35 µm. The hole for circuit layer connection was drilled at the required position of the laminate. The laminate was subjected to pretreatment, sensitization and electroless plating for plating and inoculation to form a metal layer on the wall of each hole. A resist was formed on the portion of the outermost copper layer to be a circuit. The outermost copper layer of the exposed (resistless) portion was removed by etching to form a wiring board.

Example 7

3 including a core nickel layer and two copper layers formed on both sides of the core nickel layer on each side of the prepreg, which is a glass cloth-epoxy resin insulated substrate [GEA-67 (trade name) manufactured by Hitachi Chemical Co., Ltd.]. Laminated metal thin films, which are layer laminates, were heated under pressure to form laminates. Only portions of the laminate in which the etching resist was perforated for circuit layer connection (the diameter of each portion was slightly larger than the diameter of each hole to be drilled). The copper layer of each exposed (resist-free) laminate portion was formed only on the laminate. Each hole to be drilled out was removed using an alkaline etching solution containing tetraminine (II), salt, ammonium chloride and ammonia. Metal recesses were formed around the inlet.

The copper paste was filled with each hole and each recess by screen printing. The filled copper paste was cured in a conveyor type dryer. Similar to the copper paste bonded on each copper side surface, formed by the surface of the non-concave portion of each copper layer. Each portion of the copper paste protruding from the plane was removed using a grinder. A resist was formed on the portion of the conductor (copper layer) required for circuit formation, including the recesses filled with the copper paste. The exposed (resistless) conductor portion was removed by etching to form an inner layer circuit board. Prepreg [GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.] and a 35 μm thick copper thin film were placed on each side of the inner circuit board. The laminate was heated under pressure to form a laminate. The hole was drilled at the required position of the laminate. The laminate was subjected to pretreatment, sensitization treatment and electroless plating treatment for plating and inoculation to form a metal layer on the walls of each hole. It formed in the part of a copper layer. The outermost copper layer of the exposed (resistless) part was removed by etching, and the wiring board was obtained.

Example 8

On each side of the inner circuit board as used in Example 4, prepreg (GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.) and a copper thin film having a thickness of 35 μm were placed. The laminate was heated under pressure. Holes for connecting the circuit layer were drilled at the required positions of the laminate. The laminate was pretreated, sensitized and electroless plated to form a metal layer on the walls of each hole. The resist was removed by etching the outermost copper layer to be a circuit to obtain a wiring board.

Example 9

On each side of the inner circuit board as used in Example 1 (each hole filled with silver paste had a diameter of 1.5 mm) prepreg [GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.]] and thickness 35 A thin film of copper was placed. They were heated under pressure to form a laminate. Each of the holes for inner layer circuit and outer layer circuit connection, each 0.8 mm in diameter, was drilled in the stack so as to pass through one hole of the inner layer circuit board filled with silver paste. An etch resist was formed on the laminate to expose the pores and their proximity. Based on the relationship between the time needed for etching and the remaining copper thin film thickness obtained previously, the exposed (resistless) copper thin film portion is removed so that the remaining copper thin film thickness is about half the original thickness, thereby reducing the metal recesses. The etching resist was removed by peeling, and the same silver paste was filled in each hole and each recess by screen printing.

The filled silver paste was cured in a dryer of Conveyor type. Like the silver paste adhered on the copper thin film surface, each part of the silver paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. The resist was formed on the part of the angle body (copper thin film) required for circuit formation including the recessed part filled with the silver paste. The exposed (resistless) conductor part was removed by etching to obtain a wiring board. An etching resist was formed on the laminate so that the hole and its vicinity were exposed. Based on the relationship between the time required for etching and the remaining copper thin film thickness, the thickness of the remaining copper thin film was reduced. A metal recess was formed around each hole inlet by about half the original thickness. The etching resist was removed by peeling, and the same silver resist was screened on each hole and each recess by screen printing. The filled silver paste was cured in a conveyor type dryer. As with the silver paste adhered on each copper thin film surface, each part of the silver paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. Necessary for circuit formation, including recesses filled with silver paste A resist over part of the angle member (copper thin film) was formed to obtain a circuit board is removed by the unit (not resist) etching exposed conductor.

Example 10

On each side of the inner circuit circuit board as used in Example 3 (each hole filled with silver paste had a diameter of 1.5 mm), a prepreg (GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.) and a core was used. A metal thin film, which is a three-layer laminate consisting of a metal layer (made of nickel boron alloy) and two copper layers formed on both sides of the core metal layer by electroless plating, was placed. They were heated under pressure to form a laminate, each having a diameter of 0.8. Holes for connecting inner layer circuits and outer layer circuits in mm were drilled at the required positions of the laminate. An etching resist was formed over the laminate so that the holes and their proximate portions were exposed. Copper in each exposed (resist-free) laminate portion Only the layer was removed using an alkaline etchant containing tetraminine (II), salt, ammonium chloride and ammonia, and the gold around each opening of the hole to be drilled. A recess was formed. The etching resist was removed by peeling, and the same silver paste was filled in each hole and each recess by screen printing. The filled silver paste was cured in a conveyor type dryer. Like the silver paste, each part of the silver paste protruding from the plane formed by the non-concave portion of each copper thin film was removed using a grinder. An angle body (copper thin film) necessary for circuit formation, including a recess filled with silver paste. A resist was formed on the portion of. The exposed (resistless) conductor portion was removed by etching to obtain a wiring board.

Example 11

On each side of the inner circuit board as used in Example 2, prepreg (GEA-67N (trade name) manufactured by Hitachi Chemical Co., Ltd.) and a 35 탆 thick copper thin film were placed. The laminate was heated under pressure. Holes for connecting inner layer circuits and outer layer circuits, each 0.8 mm in diameter, were drilled into the laminate so that each hole could penetrate one hole of the inner layer circuit board filled with silver paste. It was formed on the laminate so that the vicinity was exposed. Based on the relationship between the time required for etching and the remaining copper thin film thickness obtained previously, the exposed (thin film without copper) portion of the exposed copper thin film was about half the original thickness. The thickness was removed so as to be about the thickness, thereby forming a metal recess around each hole inlet. The same silver paste was filled into each hole and each recess by screen printing. The filled silver paste was cured in a conveyor type dryer. The rain recesses of each copper thin film were similar to the silver paste adhered on each copper thin film surface. Each portion of the silver paste protruding from the plane formed by the was removed using a grinder. A resist was formed on the portion of the angled body (copper thin film) required for circuit formation, including a recess filled with silver paste. The conductor part (without resist) was removed by etching to obtain a wiring board.

Example 12

The laminate [MCL-E-67 (trade name) manufactured by Hitachi Chemical Co., Ltd.] is etched to remove unnecessary portions of each copper layer of the laminate to form an inner layer circuit board. Legs [GEA-67N (trade name) manufactured by Hidachi Kasei Koyo Co., Ltd.] are placed. On each prepreg, two core metal layers (made of nickel phosphorus alloy) and two formed on both sides of the core metal layer by electroless plating are placed. A metal thin film, which is a three-layered laminate comprising a copper layer, was placed. These were heated under pressure to form a laminate. The portion of the laminate in which the etching resist was to be perforated for circuit connection (the diameter of each portion is the diameter of each hole to be drilled). Slightly larger)) was formed on the laminate so that only the copper layer of each exposed (resistless) laminate portion was Tetraminine (II) salt, ammonium chloride And an alkali etching solution containing ammonia was used to form metal recesses around the openings of each hole to be drilled. Copper paste was filled in each hole and each recess by screen printing. The filled copper paste was cured in a conveyor type dryer. Like the copper paste adhered on each copper layer, each portion of the copper paste protruding from the plane formed by the non-concave portion surface of each copper layer was removed using a grinder. A resist was formed on the portion of the conductor (copper thin film) required for circuit formation. The exposed (resistless) conductor portions were removed by etching to form an inner layer circuit board (each hole filled with copper paste was 1.5 mm in diameter). Prepreg [Hidachi Kasei Koyo Co., Ltd.] was applied to each side of the inner layer circuit board. GEA-67N (trade name)] and core metal layer (made of nickel boron alloy) were placed on the metal thin film, which is a three-layer laminate comprising two copper layers formed on both sides of the core metal layer by electroless plating. The laminate was formed by heating. Holes for connecting inner layer circuits and outer layer circuits, each 0.8 mm in diameter, were drilled at the required positions of the laminate. An etching resist was formed on the laminate so that the holes and the proximal portions thereof were exposed. Only the copper layer of the exposed laminate portion is removed using an alkaline etchant comprising tetramincopper (II), salt, ammonium chloride and ammonia The metal recesses were formed around each of the hole inlets. The etching resist was removed by peeling, and the same copper paste was filled into each hole and each recess by screen printing. The filled copper paste was cured in a conveyor type dryer. Similar to the copper paste adhered on the surface of each copper thin film, each part of the copper paste protruding from the plane formed by the non-concave portion of each copper thin film was removed by using a grinder. A resist was formed on the portion of the required angler (copper thin film). The exposed (resistless) conductor portion was removed by etching to obtain a wiring board.

Example 13

Solder pastes containing solvents and particles of low melting point metals (e.g. solders) were used in place of silver pastes, and after being filled with respective holes and corners, the pastes were heated in a conveyor type dryer to evaporate the solvent. The wiring board was obtained in the same manner as used in Example 1, except that the solder was melted, and the solder solidified and cooled.

Example 14

MCL-437F (trade name) manufactured by Hidachi Chemical Co., Ltd., which is a laminate of paper-phenolic resin and a 35 μm copper thin film, was used in Example 2 except that it was used instead of MCL-E-67. The wiring board was obtained by the same method as that.

Example 15

Instead of MCL-E-67, a wiring board was obtained in the same manner as in Example 1 except that a copper clad laminated film obtained by laminating a 35 μm thick copper film and a polyester film using an adhesive agent was used. .

Example 16

As a laminate, a wiring board was obtained in the same manner as in Example 13, except that a solder-plated copper-clad laminate film obtained by laminating a solder-plated copper thin film and an polyimide film using an adhesive was used. Evaporation of the solvent by heating after filling the recesses, melting of the low melting point metal particles, and subsequent cooling and solidification are performed on the polyimide film (heat resistant film) side of the aluminum plate (thickness 1 mm) polyimide film, on both sides of the laminate. And by placing them in a heating furnace. As is clear from the foregoing, the wiring board of the present invention can be manufactured without electroless plating, as compared with ordinary wiring boards having through-holes. This wiring board can be manufactured in a fully automated manufacturing line. Furthermore, the plating time, which takes a large part of the overall processing time, Since the wiring board can be manufactured at a considerably lower cost, the wiring board has almost the same characteristics (except electrical characteristics) that ordinary wiring boards have. Same as other wiring boards except that they should be used at low temperatures. As regards the electrical properties, the wiring boards of the present invention using solder have almost the same characteristics as those of ordinary wiring boards. When used in a circuit in which electricity is flowing, it shows a slight decrease in voltage and cannot be used in stringent requirements such as ECL circuits. However, C-MOS semiconductors, especially low-power consumption, such as portable word processors, personal computers, etc. In the application field to be used, it can be used in the same manner as the conventional wiring board. Ming can provide a low cost wiring board with a high wiring density having substantially the same properties as a conventional wiring board, and a method for efficiently manufacturing the wiring board.

Claims (35)

An insulating layer and metal thin film layers formed on both sides of the insulating layer, each of the metal thin film layers having one or more recesses formed therein, the recesses being filled with a conductor, and holes are formed in each recess to form part of the recesses. Inner circuit wiring boards, which are held around the end of the hole The wiring board of claim 1, wherein the metal thin film is a copper thin film. An insulating layer and a metal thin film layer formed on both sides of the insulating layer, wherein the metal thin film layer has one or more recesses, one hole is drilled in one recess, and the recess is filled with a conductive material, and the metal thin film is a core metal layer and Inner circuit circuit board, characterized in that the composite metal thin film comprising a copper layer formed on one side or both sides of the core metal layer It has a metal thin film layer formed on both the insulating layer and the insulating layer and at least one hole formed through the insulating layer and the metal thin film layer, the narrow portion is concave around the end of each hole in the metal thin film layer, the recess and the hole conductive material Wiring board, characterized in that the charge The wiring board according to claim 4, wherein the metal thin film is a copper thin film. It has a metal thin film layer formed on both the insulating layer and the insulating layer and one or more holes formed through the insulating layer and the metal thin film layer, the narrow portion is concave around each hole in the metal thin film layer, and the recess and the hole are filled with the conductive material. And a metal thin film is a composite metal thin film including a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions, and the concave portion is the core metal layer or the core layer. A wiring board, characterized in that formed in one of A wiring board having one or more inner circuit boards and prepregs alternately stacked to form a stack and an outer circuit layer formed from a metal thin film layer on both outermost sides of the stack, each inner circuit board comprising an insulating layer and the insulator. A metal thin film layer formed on both sides of the layer, wherein at least one inner circuit board or at least one outer circuit layer or both inner circuit boards and outer circuit layers have recesses in the metal thin film layer, and the recesses are filled with a conductive material, and the wiring board Has at least one through hole penetrating the laminate at least in one of the recesses, and each through hole formed in the recess is filled with a conductor. The wiring board according to claim 7, wherein the metal thin film is a copper thin film. The method of claim 7, wherein the metal thin film is a composite metal thin film comprising a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer is different in chemical control conditions and the concave portion is the core A wiring board, characterized in that formed on one of the metal layer or the copper layer. Stacking and compressing a pair of metal thin films, one on each side of the insulated substrate, which is not completely cured, drilling holes required for circuit connection of the laminate, and removing the metal thin films from the narrow area around the holes in the metal thin film. Forming a recess, and filling a hole and a recess in the fluid conductive material comprising the step of manufacturing a wiring board The metal thin film of claim 10, wherein the metal thin film is a composite metal thin film including a core metal layer and a copper layer formed on one or both sides of the coder metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions, and the concave portion is provided only. Method of manufacturing a wiring board, characterized in that formed only in the core metal layer or copper layer Stacking and preheating the prepreg and the metal thin film on both sides of at least one inner circuit board, drilling a hole necessary for the circuit connection of the laminate, removing the metal thin film from the narrow area around the hole, and recessing the metal thin film Forming a portion, and filling the hole and the recess in the fluid conductive agent comprising the step of manufacturing a wiring board The method of claim 12, wherein the metal thin film is a composite metal thin film and a metal thin film comprising a core metal layer and a copper layer formed on one side or both sides of the core metal layer, the core metal layer and the copper layer has different chemical removal conditions, the concave Wiring board manufacturing method characterized in that the portion is formed only in the core metal layer or copper layer 11. The method of claim 10, wherein the step of curing the flowable conductive material, removing the protrusion of the conductive material higher than the peripheral height. Coating the surface portion necessary to form a circuit conductor including the cured conductive material with a resist, the recipe And removing the exposed portions from the etching to form an outer layer circuit. 13. The method of claim 12, further comprising: curing the flowable conductive material, removing protrusions of the conductive material higher than the peripheral height, applying the surface portion with the resist to form a circuit conductor comprising the cured conductive material, and resist And removing the exposed portion from the etching by etching to form an outer layer circuit. Stacking and compressing a pair of metal thin films, one by one, on each side of the insulated substrate that is not completely cured, drilling holes necessary for circuit connection to the laminate, and removing the metal thin films from the narrow region around the holes in the metal thin film. Forming recesses, filling the holes and recesses with a fluid conductive material to cure, removing projections of the conductive material higher than the peripheral height, and resisting the surface portion necessary to form the circuit conductor including the cured conductive material. Forming a layer circuit board by etching the exposed portions from the resist by etching, laminating prepreg and metal thin films on both sides of the one or more layer circuit boards thus produced, and hot pressing Forming a metal layer by plating on the inner wall of the hole Circuit board manufacturing method step, the step of applying an outer metal thin film with a resist, and the unnecessary metal thin film required for forming a circuit are removed by etching for forming a circuit layer outside 17. The method of claim 16, wherein the metal thin film is a composite metal thin film comprising a core metal layer and a copper layer formed on one side or both sides of the core metal layer, the core metal layer and the copper layer is different in chemical removal conditions, and the recess is only Method of manufacturing a wiring board, characterized in that formed only in the core metal layer or copper layer Stacking and compressing a pair of metal thin films, one on each side of the insulated substrate, which is not completely cured, drilling holes required for circuit connection of the laminate, and removing the metal thin films from the narrow area around the holes in the metal thin film. Forming recesses, filling the holes and recesses with the fluid conductive material to cure, removing projections of the conductive material higher than the peripheral height, and resisting the surface portion necessary to form the circuit conductor including the cured conductive material. Forming a layer circuit board by etching the exposed portions from the resist by etching, laminating prepreg and metal thin films on both sides of the one or more layer circuit boards thus formed, and hot pressing them; Drilling holes required for circuit connection in the laminate, the holes being drilled in the inner circuit board A small step size than the yoke, circuit board manufacturing method comprising the steps of forming and removing the metal thin film in the narrow region of the hole around the recess in the metal thin-film portion, and a hole and filling the fluid also reproduced in the recess 19. The method of claim 18, wherein the metal thin film is a composite metal thin film comprising a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions, and the concave portion only Method of manufacturing a wiring board, characterized in that formed only in the core metal layer or copper layer 19. The method of claim 18, further comprising the steps of curing the flowable conductive material, removing protrusions of the conductive material that are higher than the peripheral height, applying the surface portion necessary to form a circuit conductor including the cured conductive material with the resist, and resist And removing the exposed portion from the etching by etching to form an outer layer circuit. 21. The method of claim 20, wherein the metal thin film is a composite metal thin film comprising a core metal layer and a copper layer formed on one side or both sides of the core metal layer, wherein the core metal layer and the copper layer have different chemical removal conditions, and the concave portion only Method of manufacturing a wiring board, characterized in that formed only in the core metal layer or copper layer Stacking and hot pressing a pair of metal thin films, one on each side of the insulated substrate, which is not fully cured, forming circular recesses by etching in each of the metal thin films, and holes necessary for connecting circuits to the respective recesses. And a step of filling the hole and the recess into the fluid conductive material. Stacking and preheating prepreg and metal thin films on both sides of the at least one inner circuit board, forming circular recesses by etching in each of the metal thin films, and forming holes necessary for connecting circuits to the respective recesses. And a step of drilling, and filling a fluid conductive material into the hole and the recess. 23. The method of claim 22, further comprising: curing the flowable conductive material, removing the protrusion of the conductive material higher than the peripheral height, applying the surface portion with the resist to form a circuit conductor including the cured conductive material, the resist; And removing the exposed portions from the etching to form an outer layer circuit. 24. The method of claim 23, further comprising: curing the flowable conductive material, removing the protrusion of the conductive material higher than the peripheral height, applying the surface portion with the resist to form a circuit conductor including the cured conductive material, the resist; And removing the exposed portions from the etching to form an outer layer circuit. Stacking and hot-pressing a pair of metal thin films, one on each side of the insulated substrate, which is not fully cured, forming circular recesses by etching in each of the metal thin films, and holes necessary for connecting circuits to the respective recesses. Drilling a hole, filling a hole and a recess with a flowable conductive material, curing the conductive material, removing protrusions of the conductive material higher than the peripheral height, and coating the surface portion necessary to form a circuit conductor including the hardened conductive layer with a resist. Etching, removing the exposed portions from the resist by etching to form an inner layer circuit board, laminating prepreg and metal thin films on both sides of the one or more inner layer circuit boards thus formed, and hot pressing them to the laminate. Drilling a hole necessary for circuit connection; forming a metal layer by plating on the inner wall of the hole A method of manufacturing a wiring board comprising the steps of: applying an external metal thin film necessary for forming a circuit to a resist; and removing an unnecessary metal thin film by etching to form an external circuit layer. Stacking and hot-pressing a pair of metal thin films, one on each side of the insulated substrate, which is not fully cured, forming circular recesses by etching in each of the metal thin films, and holes necessary for connecting circuits to the respective recesses. Perforating, filling the holes and recesses with the fluid conductive material to cure, removing projections of the conductive material higher than the peripheral height, and applying the surface portion with the resist to form the circuit conductor including the cured conductive material. Etching to remove the exposed portion from the resist to form an inner layer circuit board; laminating and preheating prepreg and other metal thin films on both sides of the one or more inner layer circuit boards thus produced, the laminate In the step of drilling a hole required for the circuit connection to the hole, the hole is formed in the inner circuit board Circuit board manufacturing method characterized in that more diameter comprising a low step, the step of removing the metal film in the narrow region of the hole periphery by filling a liquid is also reproduced in the step, and a hole and a concave portion for forming a recessed portion in the other metal thin film 28. The method of claim 27, further comprising: curing the flowable conductive material, removing protrusions of the conductive material higher than the peripheral height, applying a surface portion with a resist to form a circuit conductor including the cured conductive material, the resist; And removing the exposed portions from the etching to form an outer layer circuit. The method of claim 10, wherein the metal thin film is a copper thin film. The method of claim 12, wherein the metal thin film is a copper thin film. The method of claim 16, wherein the metal thin film is a copper thin film. 19. The method of claim 18, wherein the metal thin film is a copper thin film. 23. The method of claim 22, wherein the metal thin films are copper thin films. The method of manufacturing a wiring board according to claim 10, wherein only a portion of each metal thin film around the inlet of each hole is removed to such an extent that the insulating substrate is not exposed to form a metal recess around the inlet of each hole. 23. The method of manufacturing a wiring board according to claim 22, wherein only a portion of each metal thin film around the inlet of each hole is removed such that the insulating substrate is not exposed to form a metal recess around the inlet of each hole.