JP2001177224A - Microwave circuit substrate and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manufacture reliable microwave circuit substrate having various kinds of three-dimensional shapes. SOLUTION: Electronic components 3 are mounted to a circuit pattern 2 formed on an insulation sheet 1, the insulation sheet 1 where the electronic components 3 are mounted being attached onto the stiff substrate 6 bent is a specific shape along the shape, and resin mold is made along the shape of the stiff substrate 6, while the electronic components 3 are embedded. After resin molding is carried out, the stiff substrate 6 and the insulation sheet 1 are peeled off for manufacturing a microwave circuit substrate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional circuit board having a built-in component and bent into a predetermined shape, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, a three-dimensional circuit board formed in a desired three-dimensional shape has been proposed as a circuit wiring board. For example, the following three-dimensional circuit boards are known as conventional three-dimensional circuit boards.

(I) A three-dimensional circuit board formed by forming a circuit pattern by subjecting copper to electroless plating after forming the board with a resin and etching the electroless plating (see JP-A-9-266368). (Ii) A three-dimensional circuit board formed by three-dimensionally forming a copper foil in advance, and simultaneously forming the preformed copper foil and a required number of prepreg sheets by heating and pressing with a forming die. 9-266368). (iii) A three-dimensional circuit board formed by providing a metal conductive film on the surface of a three-dimensional substrate and selectively removing the metal conductive film with a laser beam to form a circuit pattern (Japanese Unexamined Patent Publication No.
148803). In these three-dimensional circuit boards, mounted components, so-called electronic components, are mounted on the completed three-dimensional circuit board.

[0004]

In the above-mentioned conventional three-dimensional circuit board, in any of the cases (i) to (iii), electronic components are mounted after the three-dimensional circuit board is formed. Therefore, it is difficult to mount the electronic components due to the influence of steps or the like, and the mounting workability is deteriorated.

In the three-dimensional circuit board (i), since the circuit pattern is formed by using copper plating and selective etching, the number of manufacturing steps is increased, and plating equipment and waste liquid treatment are required in the copper plating step. Met. In the three-dimensional circuit board of the above (ii), a plurality of prepreg sheets are required, and the plurality of laminated prepreg sheets and the pre-bent copper foil are molded by heating and pressing with a molding die,
Thereafter, the circuit pattern is formed by selectively etching the copper foil to form a circuit pattern, but the manufacturing process is complicated. (Iii) above
In the three-dimensional circuit board, since a circuit pattern is formed by using a laser beam, large-scale manufacturing equipment is required. Further, in manufacturing a three-dimensional circuit board, it has been difficult to directly convert a flat board into a three-dimensional board.

SUMMARY OF THE INVENTION In view of the above, the present invention provides a three-dimensional circuit board which can be formed into a predetermined three-dimensional shape, protects mounted components, and facilitates manufacturing, and a method of manufacturing the same. is there.

[0007]

In the three-dimensional circuit board according to the present invention, a mounting component connected to a circuit pattern is embedded in a resin board bent into a predetermined shape, and the circuit pattern is formed on one surface of the resin board. The configuration is such that it faces.

In the three-dimensional circuit board of the present invention, since the mounted components are embedded in the resin substrate bent into a predetermined shape by the mold resin while being mounted on the circuit pattern, the mounted components are protected by the resin substrate. In addition, the mounting of the mounted components has already been completed at the time of being configured as a three-dimensional circuit board, and various three-dimensional shapes are possible.

A method for manufacturing a three-dimensional circuit board according to the present invention comprises:
The mounting component is mounted on the circuit pattern formed on the insulating sheet, and the insulating sheet on which the mounting component is mounted along the predetermined shape is stuck on a rigid substrate bent into a predetermined shape, and the mounting component is embedded. Then, resin molding is performed along the shape of the rigid substrate.

In the method of manufacturing a three-dimensional circuit board according to the present invention, since the mounted components are mounted in a planar state on the insulating sheet on which the circuit pattern is formed, the mounting operation can be easily performed. After the insulating sheet is adhered along the predetermined shape on the rigid substrate bent into the predetermined shape, and then resin molded along the shape of the rigid substrate so as to embed the mounted components, the three-dimensional shape bent into the predetermined shape is used. The circuit board can be easily manufactured. Since the mounted components are embedded in the resin mold, they are protected at the same time when the production of the three-dimensional circuit board is completed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a three-dimensional circuit board according to the present invention, mounted components connected to a circuit pattern are embedded in a resin board bent into a predetermined shape, and the circuit pattern faces one surface of the resin board. Configuration.

[0012] The method for manufacturing a three-dimensional circuit board according to the present invention comprises:
A step of mounting the mounted components on a circuit pattern formed on the insulating sheet, a step of attaching an insulating sheet on which the mounted components are mounted along the predetermined shape to a rigid substrate bent into a predetermined shape, and a step of mounting. A step of resin molding along a predetermined shape of the rigid substrate so as to embed the component. The present invention further includes a step of removing the rigid substrate and the insulating sheet from the resin-molded substrate after the resin molding.

Hereinafter, an embodiment of a three-dimensional circuit board and a method of manufacturing the same according to the present invention will be described with reference to FIGS.

In this embodiment, first, as shown in FIG. 1A, a flexible insulating sheet, for example, a resin sheet 1 made of polyester or the like is prepared, and for example, on one surface of the resin sheet 1, for example, A predetermined circuit pattern 2 is formed by applying a conductive adhesive by printing. The conductive adhesive can be formed by, for example, dispersing conductive particles, for example, Cu particles, Ag particles, or particles obtained by coating the surfaces of Cu particles with an Ag film, on a thermosetting resin.

Next, as shown in FIG.
Components, so-called electronic components (for example, leadless components,
3) are mounted. in this case,
The electronic component 3 is placed so as to be in contact with the terminal portion 4 or the lead portion 5 or the circuit pattern 2. The mounting of the electronic component 3 is performed in a state where the resin sheet 1 is flat.

Next, as shown in FIG. 1C, the conductive adhesive as the circuit pattern 2 is cured by heating. By this heat curing treatment, the circuit pattern 2 is cured, and each electronic component 3 is electrically and mechanically connected to the circuit pattern 2.

Next, as shown in FIG. 1D, a rigid substrate 6 having a predetermined bent shape is prepared by bending, molding or the like, and an electronic component is placed on one surface of the rigid substrate 6 with an adhesive 7 interposed therebetween. The insulating sheet 1 on which the substrate 3 is mounted is attached so that the back surface faces the rigid substrate 6 side. The insulating sheet 1 is adhered along the bent shape of the rigid substrate 6 to have flexibility. As the rigid substrate 6, for example, a metal substrate such as an Al substrate, a resin substrate having high hardness, or the like can be used. At least, the resin substrate in a later step can withstand without deformation in shape and can be peeled off after the resin molding. Rigid substrates having various properties may be used.

Next, as shown in FIG. 2E, a bent structure 8 formed by attaching the insulating sheet 1 on which the electronic components 3 are mounted to a bent rigid substrate 6 is attached to a frame jig (for example, an injection mold or the like). ) 9 and resin 10 is embedded. That is, resin molding is performed.

Next, after the resin 10 is cured, as shown in FIG. 2F, a bent body molded with resin, that is, a so-called resin molded bent structure 11 is taken out from the frame jig 9.

Next, as shown in FIG. 2G, the rigid substrate 6 is peeled off together with the resin sheet 1 from the resin mold bent structure 11. As a result, the electronic component 3 is embedded in the resin substrate 13 formed by the resin mold formed along the bent shape of the rigid substrate 6, and the circuit pattern 2 connected to the electronic component 3 is exposed on one surface of the resin substrate 13. The three-dimensional circuit board 12 according to the present embodiment thus formed is completed.

According to the present embodiment, by selecting the bent shape of the rigid substrate 6, it is possible to manufacture the three-dimensional circuit board 12 adapted to electronic device cases of various shapes. Since the entire three-dimensional shape is maintained by the resin substrate 13 formed of the resin mold, a circuit board having a predetermined three-dimensional shape can be easily obtained without requiring components such as screws and ribs.

In the three-dimensional circuit board 12 of the present embodiment, since each electronic component 3 is embedded in the resin substrate 13 and protected, the electronic component 3 is hardly broken.
Since the mounting of the electronic component 3 can be performed with the insulating sheet 1 being flat, the mounting operation is facilitated. In the present embodiment, the three-dimensional circuit board 12 can be easily manufactured with simple manufacturing equipment.

The three-dimensional circuit board 12 of this embodiment can form a space-saving circuit board in combination with mechanical parts and other boards.

After the three-dimensional circuit board 12 is manufactured in the process shown in FIG. 2G, if necessary, an insulating film and an insulating coat film for protecting the circuit pattern 2 exposed to the outside except for the terminal portions. May be formed on the surface of the three-dimensional circuit board 12.

FIG. 2F shows another embodiment of the present invention.
It is also possible to use the bent structure 11 to which the rigid substrate 6 obtained in the step is attached as it is for a three-dimensional circuit board. In this case, the terminal portion of the circuit pattern 2 is exposed to the outside by appropriate means. According to such a three-dimensional circuit board, the rigid board 6 can function as a reinforcing member. If the rigid substrate 6 is formed of a metal substrate and is set at the ground potential, the electronic component 3 and a circuit including the same can be provided with a shielding function.

[0026]

According to the three-dimensional circuit board of the present invention, it is possible to form a three-dimensional circuit board of a free shape having no components such as screws and ribs. A three-dimensional circuit board adapted to electronic device cases of various shapes can be configured.

Since the three-dimensional circuit board is configured with the mounted components already mounted and embedded, a space-saving three-dimensional circuit board can be obtained in combination with mechanical parts and other substrates. Since the mounted components are protected by being embedded in the resin substrate, a three-dimensional circuit board having high reliability and being hardly damaged can be obtained.

According to the method for manufacturing a three-dimensional circuit board according to the present embodiment, a three-dimensional circuit board having an integral structure can be easily manufactured without using components such as screws and ribs. In forming the circuit pattern, a patterning step by laser light, etching, or the like is not required, and the manufacturing process can be simplified. The manufacturing equipment is not large and there is no need for waste liquid treatment.

By selecting the shape of the rigid board, it is possible to manufacture a three-dimensional circuit board suitable for electronic device cases of various shapes.

Since the mounted components are embedded in the resin mold, the mounted components can be protected, and a three-dimensional circuit board with high reliability in which the mounted components are hardly damaged can be manufactured. Since mounting of the mounted components is performed in a state where the insulating sheet is flat, component mounting can be performed easily and reliably.

[Brief description of the drawings]

1A to 1D are manufacturing process diagrams (part 1) illustrating one embodiment of a method for manufacturing a three-dimensional circuit board according to the present invention.

2A to 2G are manufacturing process diagrams (part 2) illustrating one embodiment of a method of manufacturing a three-dimensional circuit board according to the present invention.

[Explanation of symbols]

1} Insulation sheet, 2} Circuit pattern with conductive adhesive, 3} Electronic components, 4} Terminal part, 5} Lead part, 6} Rigid board, 7} Adhesive, 8% folding Song structure,
9 mm frame jig, 10 mm resin, 11 mm resin mold structure, 12 mm three-dimensional circuit board, 13 mm resin board

Claims (3)

[Claims] 1. A three-dimensional circuit, wherein a mounting component connected to a circuit pattern is embedded in a resin substrate bent into a predetermined shape, and the circuit pattern faces one surface of the resin substrate. substrate. 2. A step of mounting a mounted component on a circuit pattern formed on an insulating sheet, and attaching an insulating sheet on which the mounted component is mounted along a rigid substrate bent in a predetermined shape. Performing a resin molding along the shape of the rigid substrate so as to embed the mounted component. 3. The method for manufacturing a three-dimensional circuit board according to claim 2, further comprising a step of separating the rigid substrate and the insulating sheet after the resin molding.