JP3582645B2 - Manufacturing method of three-dimensional wiring board - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a three-dimensional wiring board used for mounting electronic components and the like.
[0002]
[Prior art]
Conventionally, a plurality of electronic components such as semiconductor elements and chip components are mounted on a planar wiring board on which predetermined circuit conductors are formed to form a module substrate, or a hybrid IC is mounted on a motherboard in a planar manner. .
With reference to FIG. 6, a description will be given of a state in which electronic components are mounted on a conventional planar wiring board 10 as a module substrate, and then mounted on a motherboard in a planar manner.
First, predetermined circuit conductors, connection lands 3 for electronic components, through holes 4, and end electrodes 5 of a flat wiring board for electrically connecting to the outside are formed on a double-sided or multilayer flat wiring board 10. ing.
The chip-type electronic component 30 is mounted on the connection land 3 on the upper surface of the flat-type wiring board 10 with the solder 35 and electrically connected.
[0003]
Next, the module board on which the plurality of chip-type electronic components 30 are mounted is heated and connected to the connection terminals 45 of the mother board 40 by using the end surface electrodes 5 provided on the flat wiring board 10 described above.
The flat-type wiring board 10 is provided with predetermined circuit conductors, connection lands, bonding pads, etc. on both sides of the flat-type wiring board or on both sides of the multilayer flat-type wiring board, and electronic components are provided on both sides of the flat-type wiring board 10. A spacer substrate, a connector, a pin board, and the like are attached to the lower surface, which is the lower portion of the flat wiring board 10 which is to be mounted on the motherboard after mounting on the motherboard, and mounted on the motherboard.
In order to stably mount the module substrate having the plurality of chip-type electronic components 30 mounted on the flat-type wiring board 10 on the motherboard 40, the chip-type electronic components 30 are usually provided on the lower surface on the back side of the flat-type wiring board 10. Are not installed.
[0004]
[Problems to be solved by the invention]
Conventionally, mounting a module board with chip-type electronic components mounted on both front and back sides of a flat-type wiring board in close contact with the motherboard requires mounting a spacer or connector on the lower side of the module board that is in contact with the motherboard board from the motherboard I needed to float it. That is, it has been difficult to mount the chip-type electronic components on the lower side of the flat-type wiring board at high density and horizontally mounted on the motherboard substrate.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a process of manufacturing an upper wiring board for forming circuit conductors and connection lands serving as an inner layer circuit on the back side of a double-sided copper-clad laminate, and a single-sided copper-clad laminate and an adhesive resin. And a step of manufacturing a lower wiring board for forming an electronic component housing portion on a copper foil material with the lower wiring board attached to the back side of the upper wiring board. The component housing portion is filled with a filling resin, and an outer layer circuit conductor is formed on the integrated wiring board.
A three-dimensional wiring board having an inverted concave-shaped electronic component storage portion on the lower back surface of the flat-shaped wiring board has a chip-shaped electronic component mounted on a connection land of an inner layer circuit in an exposed hole of the inverted concave shape. The present invention is to provide a method of manufacturing a three-dimensional wiring board in which the entirety of a chip-type electronic component can be stored at a high density in a storage portion of the electronic component.
[0006]
Manufacturing method 1 includes the following method.
Providing a through-hole for electrically connecting both sides of the double-sided copper-clad laminate, forming metal conductor layers on both end surfaces of a non-through conductive hole formed by filling a filler in the through-hole; Forming a circuit conductor or connection land to be an inner layer circuit only on the back surface side of the laminate; a first step of manufacturing an upper wiring board;
A second step of manufacturing a lower wiring board, comprising: a step of forming an adhesive layer on the insulating resin surface of the single-sided copper-clad laminate; and a step of forming a through hole serving as an electronic component housing portion.
After manufacturing the first step and the second step separately, a step of heat-pressing and integrating the lower wiring board on the back side of the upper wiring board via an adhesive layer of the lower wiring board; A step of filling and drying a filling resin in the inverted concave-shaped electronic component storage portion of the integrated wiring board; a step of forming an outer layer circuit conductor in the integrated wiring board; and removing the filling resin in the electronic component storage section. And a third step of forming an outer layer circuit conductor on an integrated wiring board comprising the steps of:
[0007]
Manufacturing method 2 includes the following method.
Providing a through-hole for electrically connecting both sides of the double-sided copper-clad laminate, forming metal conductor layers on both end surfaces of a non-through conductive hole formed by filling a filler in the through-hole; Forming a circuit conductor or connection land to be an inner layer circuit only on the back surface side of the laminate; a first step of manufacturing an upper wiring board;
A second step of manufacturing a lower wiring board for forming a through hole serving as an electronic component housing portion in a copper foil material with an adhesive resin;
After the first step and the second step are separately manufactured, a step of heat-pressing and integrating the lower wiring board on the back surface side of the upper wiring board via an adhesive resin of the lower wiring board; A step of filling and drying a filling resin in an inverted concave-shaped electronic component storage portion of the integrated wiring board; a step of forming an outer layer circuit conductor in the integrated wiring board; and removing the filling resin in the electronic component storage portion. And a third step of forming an outer layer circuit conductor on the integrated wiring board comprising the steps of:
[0008]
In the manufacturing method 1 and the manufacturing method 2, a step of forming a through hole near a non-through conductive hole filled with a filler in the first step of manufacturing the upper wiring board; Removing the resin portion of the lower wiring board with a laser beam from above the through-hole of the upper wiring board to the integrated wiring board by heat-pressing with an adhesive; and through-holes and non-through holes of the integrated wiring board and A step of performing panel plating on the front and back surfaces of the outer layer may be added.
Further, in the first step of manufacturing the upper wiring board, a multilayer wiring board having an inner layer circuit conductor is applied instead of the double-sided copper-clad laminate, or in the second step of manufacturing the lower wiring board, an adhesive resin is used. This is a method for manufacturing a three-dimensional wiring board to which a double-sided copper-clad laminate can be applied instead of the copper foil provided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
First Embodiment A method for manufacturing a three-dimensional wiring board according to a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1 (a), a predetermined NC hole 12 is drilled in the double-sided copper-clad laminate 1, and then electroless plating and electrolytic plating are performed as shown in FIG. A through hole 4 for electrically connecting the copper foil is formed.
Thereafter, the through-holes 4 arranged in the electronic component storage portion penetrate the flat-type wiring board, so that the flux, the sealing resin, the processing liquid, and the like do not penetrate into the through-holes 4 so that acid-resistant thermosetting with a small shrinkage rate is obtained. A filling material 6 such as a conductive resin or an ultraviolet curable resin is filled to form a non -penetrating conduction hole 7 which becomes a non-penetrating through hole.
Further, after forming a second plating layer in contact with the non-through conductive hole 7 by electroless plating or electrolytic plating on the end face of the non-through conductive hole 7 filled with the filler 6, the back surface of the double-sided copper-clad laminate 1 ( The circuit conductors and the connection lands 3 to be the inner layer circuits are formed only on the (lower) side.
Is intended to form the metal conductor layer in contact with both end faces of the non-through conducting holes 7 filled with packing 6 and the non-through conducting hole 7, so-called flat-through hole 7A, both the non-through conducting hole 7 By forming circuit conductors serving as inner-layer circuits and connection lands 3 for electronic components on the flattened end surface, high-density electronic component mounting can be achieved.
That is, the above-mentioned circuit conductor is formed by forming a circuit conductor to be an inner layer circuit, a connection land 3 of an electronic component and the like only on the back surface (lower surface) side of the double-sided copper-clad laminate 1 by a photographic method or a printing method. It is.
The above steps are referred to as a first step, and the inner layer circuit conductor B on the back surface of the upper wiring board 1A is formed.
[0010]
Then, as shown in FIG. 1C, an adhesive layer 13 is formed on the insulating resin surface on the upper side of the single-sided copper-clad laminate 1 with a semi-cured prepreg, an adhesive, an adhesive sheet, or the like. The process of manufacturing the lower wiring board 1B by forming a through hole 14 having a specified shape at a predetermined position of the single-sided copper-clad laminate 1 by press working, router working, milling, or the like is referred to as a second step.
In addition, it is preferable to use a low-flow type adhesive sheet in which the flow of the adhesive into the through hole 14 is small as the adhesive layer 13.
In the second step of manufacturing the lower wiring board 1B, a double-sided copper-clad laminate is applied instead of the single-sided copper-clad laminate, and the multilayered structure is increased by laminating the upper wiring board via a prepreg. You can also.
[0011]
Next, a post-process of Example 1 of the method for manufacturing a printed wiring board of the present invention will be described with reference to FIG.
As shown in FIG. 2D, the lower wiring board 1B formed in the second step is placed on the back side of the upper wiring board 1A formed in the first step via the adhesive layer 13 in the semi-cured state. Heat-compression bonding and lamination integration.
As the above-mentioned thermocompression bonding conditions, the pressure was set to a pressure of 50 to 70 kgf / cm ² , which is about twice the normal pressure, and a heating condition of about 140 ° C. to 180 ° C. for 60 minutes.
Next, as shown in FIG. 2E, a desired NC hole 12 penetrating the upper wiring board 1A and the lower wiring board 1B is formed at a predetermined position.
[0012]
Then, as shown in FIG. 2 (f), electroless plating and electrolytic plating are performed to form through holes 4 for electrically connecting the conductors on the front and back surfaces of the integrated substrate and connection terminals for chip-type electronic components. A through hole 4 is formed as an end surface electrode.
Then, the inner layer circuit conductor inside the electronic component housing hole and the inner layer circuit conductor such as the connection land 3 of the electronic component are subjected to a through-hole plating step, a step of forming an outer layer circuit conductor on the surface of the wiring board, and a step of noble metal. In the plating process, etc., the inner layer circuit conductors are removed from the plating and etching so that the inner layer circuit conductors inside the already formed electronic component storage holes do not cause circuit defects or quality defects due to contamination or damage due to plating adhesion or etching. For protection, a filling resin 15 such as a thermosetting resin or an ultraviolet curable resin is filled in the inside of the hole 16 of the inverted recess which is opened to one side in the inverted recess so that the end of the hole 16 of the inverted recess is almost covered. Fill.
[0013]
Then, as shown in FIG. 2 (g), the upper and lower wiring boards 1A and 1B are laminated and integrated on the entire surface of the front and back outer layers of the multilayer wiring board by a printing method or a photographic method. After forming an etching resist and forming predetermined outer layer circuit conductors, connection lands 3 of electronic components and the like by etching, the filling resin is dissolved and removed to manufacture a multilayer wiring board.
The three-dimensional wiring according to the first embodiment, which is a multilayer wiring board of an integrated board, is formed by forming the outer layer circuit conductor A on the upper surface of the upper wiring board 1A and the outer layer circuit conductor C on the lower back surface of the lower wiring board 1B in this manner. The plate 18 is manufactured.
Incidentally, it is common to form a nickel-plated or gold-plated layer on the inner layer circuit conductor inside the electronic component storage hole, the connection land 3 of the electronic component, etc. so that the connection with the electronic component is good (FIG. Not shown).
[0014]
The substrate of the upper wiring board 1A and the lower wiring board 1B of the three-dimensional wiring board of the present invention is made of a thermosetting resin such as an epoxy resin, a phenol resin, a polyester resin, a polyimide resin, or a BT resin resin. A substrate made of a material obtained by impregnating a base material of inorganic fibers such as silicon, organic fibers such as polyester, polyamide, polyimide and polyacryl, and natural fibers such as cotton and paper can be selected.
Although the embodiments of the present invention have been described in detail with reference to a three-layer planar wiring board, the present invention can be applied to a method of manufacturing a multilayer planar wiring board having three or more layers.
[0015]
Next, a method for manufacturing the three-dimensional wiring board 18 according to the second embodiment will be described with reference to FIGS.
FIG. 3A is the same as the first embodiment. Next, in the process shown in FIG. 3B, the inside of the through hole 4 of the first embodiment is filled with a filler 6 to form a non-through conduction hole 7. Electroless plating or electrolytic plating is used to form a second plating layer in contact with the non-through conductive hole 7 on the end surface on the through conductive hole 7, that is, it is desired to penetrate the double-sided copper-clad laminate 1 in addition to the flat through hole 7A. After the NC holes 12 are drilled as specified, circuit conductors and connection lands 3 are formed only on the back (lower) side of the double-sided copper-clad laminate 1.
[0016]
FIG. 3C shows the use of a copper foil 11 with an adhesive resin 13 in order to efficiently and inexpensively manufacture a thin, high-density three-dimensional wiring board 18.
In order to mount the chip-type electronic component on a copper foil 11 material with an adhesive resin 13, for example, a copper foil material with an adhesive resin which is a copper-clad film body, a through hole 14 having a specified shape is pressed at a predetermined position. The step of manufacturing the lower wiring board 1B by forming by router processing, milling processing, laser processing, or the like is defined as a second step.
The thickness of the lower wiring board 1B needs to be slightly larger than the thickness of the chip-type electronic component in order to mount the chip-type electronic component inside the through hole 14.
That is, the thickness of the lower wiring board 1B is often set to 0.2 mm to 1.0 mm.
[0017]
Then, a post-process of the method for manufacturing a three-dimensional wiring board according to the second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 4 (d), the lower wiring board 1B of the copper foil 11 with the adhesive resin 13 formed in the second step is mounted on the back (lower) side of the upper wiring board 1A formed in the first step. Then, they are laminated and integrated by heating and pressure bonding via an adhesive resin 13 in a semi-cured state to form a multilayer wiring board.
On the back (lower) side of the three-dimensional wiring board 18, a hole 16 of an inverted recess for mounting a chip-type electronic component is formed.
[0018]
Next, as shown in FIG. 4 (e), laser light is irradiated from above the NC hole 12 penetrating the upper wiring board 1A using the NC hole 12 as a shielding mask, and the copper foil 11 on the rear surface side of the lower wiring board 1B is irradiated. Until then, the semi-cured adhesive resin 13 is removed to form the non-through hole 2 in which one lower surface of the lower wiring board 1B is closed with only the metal conductor.
[0019]
Then, as shown in FIG. 4 (f), an upper wiring board 1A and a lower wiring board 1B are laminated, laminated and integrated, and then subjected to electroless plating and electrolytic plating to obtain the front and back of the multilayer wiring board as an integrated substrate. A non-through conductive hole 8 is formed in which one lower surface of the lower side of the lower wiring board 1B for electrically connecting the copper foils on both sides is closed with a metal conductor only.
The non-through conductive hole 8 whose one end face is closed only with a metal conductor has a hollow inside, and one end face as an end face electrode for use as a connection terminal of a chip-type electronic component is closed with only the metal conductor. The non-through conduction hole 8 is formed.
Next, a filling resin 15 is sufficiently filled into the hole 16 of the inverted recess for mounting the chip-type electronic component of the lower wiring board 1B by a roll coater method, a squeegee printing method, a dispenser method, etc., and then dried and polished. Thus, the metal conductor on the lower surface of the lower wiring board 1B is made substantially flat.
[0020]
Then, as shown in FIG. 4 (g), the upper and lower wiring boards 1A and 1B are laminated and integrated on the entire surface of both front and back outer layers of the multilayer wiring board by a printing method or a photographic method. This is a step of forming an etching resist, forming predetermined circuit conductors, connection lands 3 of electronic components, and the like by etching, dissolving and removing the filling resin, and manufacturing a multilayer wiring board by a subtractive method.
By forming the outer circuit conductors A on the upper surface of the upper wiring board 1A and the outer circuit conductors C on the lower rear surface of the lower wiring board 1B, a multilayer wiring board of an integrated board is manufactured.
A substantially central portion of the non-through conductive hole 8 in which one end face in which the inside of the hole is hollow is closed with only the metal conductor is cut and divided, and a chip-type electronic component having the end face electrode 5 exposed is mounted outside. To manufacture a three-dimensional wiring board 18 according to the second embodiment.
In other words, the inside of the two holes, the through hole 4 for electrically connecting the conductors on both the front and back surfaces of the integrated substrate of Example 1 and the through hole 4 as the end face electrode 5 which is the connection terminal of the wiring board, is hollowed out. One end face can be replaced with one of the non-through conduction holes 8 closed only by the metal conductor.
In the method of manufacturing the three-dimensional wiring board 18 according to the second embodiment, the outer layer surface circuit conductor may be formed by an additive method.
[0021]
Based on FIG. 5, a method of mounting electronic components on a three-dimensional wiring board 18 of an integrated substrate to form a module substrate and a state in which the module substrate is mounted on a motherboard 40 will be described in detail.
The chip-type electronic component 30 or the hybrid IC is formed on the connection land 3 of the electronic component formed on the upper surface of the three-dimensional wiring board 18 of the second embodiment described above with reference to FIGS. For example, the surface of the chip-type electronic component 30 that is thinner than the depth of the inverted concave portion is soldered to the connection land 3 of the electronic component formed on the inner bottom surface exposed in the electronic component housing 20 by soldering. The electronic component can be mounted and mounted on a connection pad of a ball grid array (BGA) such as a solder ball by electrical connection and mechanical fixing.
[0022]
Then, both sides of the three-dimensional wiring board 18, that is, the flat surface of the upper part of the three-dimensional wiring board 18 of the integrated substrate and the electronic component housing 20 of the inverted concave structure on the back side of the three-dimensional wiring board 18, The module substrate completed by mounting and mounting the electronic component 30 is connected to the connection land of the outer layer circuit conductor C on the lower side of the three-dimensional wiring board 18 with the electronic component housing 20 in the inverted recess of the three-dimensional wiring board 18 as the lower side. Are mounted in close contact with the connection terminals 45 of the motherboard 40, and are connected to the end surface electrodes 5 of the module substrate by solder 35 to be closely attached and mounted.
Further, the three-dimensional wiring board 18 having the concave portion of the inverted concave structure according to the present invention has a surface outer layer circuit conductor C formed on the lower side, and forms connection lands, BGA connection pads, connection electrode terminal portions, and the like. Then, direct electrical connection with the connection terminal 45 of the motherboard 40 can be achieved by soldering, wire bonding, or the like.
[0023]
【The invention's effect】
As described above, the method for manufacturing a flat wiring board of the present invention has the following effects.
(1) In a three- or more-layer three-dimensional wiring board, various electronic components are mounted on the outer layer circuit conductor on the upper surface, and the inside of the hole opened to the outside of the inverted recess on the lower back surface of the three-dimensional wiring board. Various types of chip-type electronic components are mounted on the exposed flat inner layer circuit conductors so that they do not protrude from the bottom side of the lower surface of the three-dimensional wiring board, and the chip-type electronic components are stored at high density. And a method for manufacturing a three-dimensional wiring board that can be provided.
(2) Non-through conduction in which through-holes are filled with a filler to electrically connect the outer layer circuit conductor on the upper surface of the integrated substrate and the inner layer circuit conductor exposed in the electronic component housing portion of the inverted recess on the lower rear surface. Manufacture of three-dimensional wiring boards on which electronic components can be mounted at high density by applying flat through holes that form metal conductor layers on both end surfaces of the holes, and using both end surfaces of the non-through conduction holes as connection lands. Is the way.
(3) The central part of the non-through conductive hole, in which the inside of the hole is hollowed out, is cut and divided in order to electrically connect the conductors on both the front and back surfaces of the multilayer wiring board and to use it as the end face electrode of the wiring board. A three-dimensional wiring board having an end face electrode exposed to the outside can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a pre-process explaining a method for manufacturing a three-dimensional wiring board of Example 1.
FIG. 2 is a cross-sectional view of a post-process explaining a method for manufacturing a three-dimensional wiring board of Example 1.
FIG. 3 is a cross-sectional view of a pre-process illustrating a method for manufacturing a three-dimensional wiring board of Example 2.
FIG. 4 is a cross-sectional view of a post-process explaining a method for manufacturing a three-dimensional wiring board of Example 2.
FIG. 5 is a cross-sectional view illustrating a state in which chip-type electronic components are mounted on a three-dimensional wiring board and mounted on a motherboard.
FIG. 6 is a cross-sectional view illustrating a state in which a chip-type electronic component is mounted on a conventional planar wiring board and mounted on a motherboard.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Copper-clad laminate 2 ... Non-through hole 3 ... Connection land 4 ... Through hole 5 ... End face electrode 6 ... Filling 7 ... Non-through conduction hole 7A ... Flat through hole 8 ... One end face was closed only by metal conductor. Non-through conduction hole 10 ... Planar wiring board 11 ... Copper foil 12 ... NC hole 13 ... Resin 14 ... Through hole 15 ... Filled resin 16 ... Reverse recessed hole 18 ... Three-dimensional wiring board 20 ... Electronic component housing 30 ... Chip Shaped electronic components 35 solder 40 motherboard 45 connection terminals.

Claims (2)

Providing a through-hole for electrically connecting both sides of the double-sided copper-clad laminate, forming metal conductor layers on both end surfaces of a non-through conductive hole formed by filling a filler in the through-hole; Forming a circuit conductor or connection land to be an inner layer circuit only on the back surface side of the laminate; a first step of manufacturing an upper wiring board;
A second step of manufacturing a lower wiring board, comprising: a step of forming an adhesive layer on the insulating resin surface of the single-sided copper-clad laminate; and a step of forming a through hole serving as an electronic component housing portion.
After manufacturing the first step and the second step separately, a step of heat-pressing and integrating the lower wiring board on the back side of the upper wiring board via an adhesive layer of the lower wiring board; A step of filling and drying a filling resin in the inverted concave-shaped electronic component storage portion of the integrated wiring board; a step of forming an outer layer circuit conductor in the integrated wiring board; and removing the filling resin in the electronic component storage section. And a third step of forming an outer layer circuit conductor on the integrated wiring board comprising the steps of: (a) forming a three-dimensional wiring board; Providing a through-hole for electrically connecting both sides of the double-sided copper-clad laminate, forming metal conductor layers on both end surfaces of a non-through conductive hole formed by filling a filler in the through-hole; Forming a circuit conductor or connection land to be an inner layer circuit only on the back surface side of the laminate; a first step of manufacturing an upper wiring board;
A second step of manufacturing a lower wiring board for forming a through hole serving as an electronic component housing portion in a copper foil material with an adhesive resin;
After the first step and the second step are separately manufactured, a step of heat-pressing and integrating the lower wiring board on the back surface side of the upper wiring board via an adhesive resin of the lower wiring board; A step of filling and drying a filling resin in an inverted concave-shaped electronic component storage portion of the integrated wiring board; a step of forming an outer layer circuit conductor in the integrated wiring board; and removing the filling resin in the electronic component storage portion. And a third step of forming an outer layer circuit conductor on the integrated wiring board comprising the steps of: (a) producing a three-dimensional wiring board;

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