JPH09199632A - Electronic component mounting substrate and its fabrication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heating properties and hence facilitate drilling by providing a heat dissipation metal plate on the upper surface side of a multi-layered substrate composed of a flexible film and a conductor circuit using the flexible film as an insulating substrate. SOLUTION: An electronic component mounting substrate 9 includes a multi- layered substrate 1 composed of electrically insulating flexible films 11 to 13, and two layers conductor circuits 31, 33 provided in the thickness direction of the flexible film, through-holes 110, 120, 130 passing through all of the flexible films 11 to 13, and a heat dissipation metal plate 2 provided on the upper surface side of the multi-layered substrate 1 so as to cover the through-holes. For this, the entire rigidity of the electronic component mounting substrate 9 is ensured with the aid of the heat dissipation metal plate 2. Thus, the heat dissipation metal plate 2 satisfactorily compensates for the lack of mechanical strength of the flexible films 11 to 13, and hence mechanical strength and durability of the electronic component mounting substrate are improved.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electronic component mounting substrate in which a plurality of layers of conductor circuits are provided in the thickness direction of the substrate, and in particular to an electronic component mounting substrate having excellent heat dissipation and easy drilling. The manufacturing method is related.

[0002]

2. Description of the Related Art Conventionally, as an electronic component mounting substrate, for example, as shown in FIG. 27, a mounting pad 97 for mounting an electronic component 8 and a conductor circuit 93 provided around the mounting pad 97. , And through holes 921 connected to the conductor circuit 93. The mounting pad 97 is an insulating substrate 9
1 is provided on the lower surface side, and the surface thereof is covered with a sealing resin 94 so as to seal the electronic component 8. The electronic component 8 and the conductor circuit 93 are connected by a wire 98.

[0003]

However, in the above conventional electronic component mounting board 991, the electronic component 8 is sealed by the sealing resin 94. Therefore, the heat generated during the operation of the electronic component cannot be smoothly released from the electronic component 8.

Therefore, it is conceivable to provide a heat radiating through hole 922 penetrating the insulating substrate 91 by drilling in a portion located above the electronic component 8. The inner wall of the heat dissipation through hole 922 is covered with a metal plating film 920. The heat generated from the electronic component 8 is transmitted to the lower surface side of the insulating substrate 91, which is the side opposite to the mounting side of the electronic component 8, through the heat dissipation through hole 922.

However, when the electronic component mounting board 991 is mounted on the mother board 995, the insulating board 91
The lower surface side of the will be arranged facing the mother board 995. Therefore, heat dissipation through hole 922
Even if the heat is transferred to the lower surface side by the, the dissipation of the heat is blocked by the motherboard 995.

Further, by providing the through holes 922 for heat dissipation, the number of drilling in the insulating substrate 91 increases,
Worn out drill drills. In particular, the insulating substrate 91
When using hard glass epoxy resin as
The consumption is large. Such wear of the drill is not preferable in terms of accuracy of drilling, and also costs the cost of drilling.

Further, since the electronic component mounting substrate 991 uses one insulating substrate, its surface area is limited, and it is difficult to mount the conductor circuits 93 in high density. Therefore, it is possible to achieve high-density wiring by stacking a large number of insulating substrates. However, stacking a large number of insulating substrates further deteriorates the heat dissipation of the electronic component mounting substrate.

In view of the above conventional problems, the present invention is excellent in heat dissipation, can easily perform drilling, and
An object is to provide a substrate for mounting electronic components and a method for manufacturing the same, which enables high-density wiring.

[0009]

According to a first aspect of the present invention, there is provided at least one electrically insulating flexible film, and a multilayer substrate including a conductor circuit provided in two or more layers in the thickness direction of the flexible film, and the flexible substrate. A through hole that penetrates the entire film, a heat dissipation metal plate provided on the upper surface side of the multilayer substrate so as to cover the through hole, and an electronic component formed by the through hole and the heat dissipation metal plate. An electronic component mounting substrate having a mounting recess and a through hole provided in the multilayer substrate and electrically connected to the conductor circuit.

What is most noticeable in the present invention is that at least one flexible film is used as an insulating substrate, and a heat-dissipating metal plate is provided on the upper surface side of a multilayer substrate including a flexible film and a conductor circuit having two or more layers. That is.

Next, the operation of the electronic component mounting board will be described. The flexible film is a thin and flexible film. Therefore, when performing the perforating process on the flexible film, the punching can be performed using the punch. The punch has less wear of the cutting edge than the drill, can make many holes in one shot, and has high drilling accuracy. Therefore, the drilling operation is easy and the drilling cost can be reduced.

Further, since the flexible film is flexible, the manufacturing process such as formation of a conductor circuit and punching can be performed while continuously drawing from a state of being bundled in a roll at the time of manufacturing.
It can be carried out sequentially and continuously. Therefore, the manufacturing process can be rationalized and simplified.

Further, the upper surface side of the mounting recess is covered with a heat dissipation metal plate. The heat dissipation metal plate is arranged on the side opposite to the side facing the motherboard when the electronic component mounting board is mounted on the motherboard. Therefore, the heat generated during the operation of the electronic component can be effectively dissipated from above the electronic component mounting board through the heat dissipation metal plate, and the heat dissipation is high.

Further, on the upper surface side of the flexible film,
It covers a hard heat dissipation metal plate. Therefore, the heat dissipation metal plate can secure the rigidity of the entire electronic component mounting board. Therefore, the heat-dissipating metal plate can sufficiently compensate for the lack of mechanical strength in the flexible film, and improve the mechanical strength and durability of the electronic component mounting board.

Also, two or more conductor circuits are laminated in the thickness direction of the flexible film. Therefore, the total area of the wirable region is increased, and the conductor circuits can be mounted at high density.

Next, as described in claim 2, the thickness of the flexible film is preferably 30 to 200 μm. If the thickness is less than 30 μm, the mechanical strength and durability of the flexible film may decrease.
On the other hand, if it exceeds 200 μm, the flexibility of the flexible film may deteriorate.

Next, as described in claim 3, it is preferable that the thickness of the heat dissipation metal plate is 50 to 1500 μm. If the thickness is less than 50 μm, the mechanical strength and durability of the electronic component mounting board may decrease. On the other hand, 1
If it exceeds 500 μm, it may hinder the thinning of the electronic component mounting substrate.

Next, as described in claim 4, it is preferable that the electronic component mounting substrate is provided with connecting means for connecting the conductor circuit and the mother board on the opening side of the mounting recess. As a result, the entire upper surface side of the multilayer substrate, which is the side opposite to the opening side of the mounting recess, can be covered with the heat-dissipating metal plate, and heat can be dissipated more efficiently. As the connecting means, a solder ball, a lead pin, an oil head for wire bonding, etc. for connecting the conductor circuit and the mother board are used.

Next, in the invention according to claim 5, the first copper foil is adhered to one surface of the electrically insulating flexible film,
Then, a through hole and a through hole for forming a mounting recess are formed in the flexible film by punching, and then the through hole is formed on the other surface of the flexible film opposite to the adhesive surface of the first copper foil. A second copper foil is adhered so as to close the hole, then the first copper foil is etched to form a conductor circuit on one side of the flexible film, and the second copper foil is etched to the other side of the flexible film. Forming a conductor circuit on one surface of the flexible film and forming a protruding pad connected to the conductor circuit and protruding inward of the through hole, and then forming an insulating adhesive on the side of the flexible film on which the protruding pad is formed. A heat-dissipating metal plate is adhered so as to cover the through-hole with a through hole to form a mounting recess made up of the through-hole and the heat-dissipating metal plate. Is a manufacturing method of the electronic component mounting board according to claim Rukoto.

This manufacturing method is a method for manufacturing an electronic component mounting substrate having a plurality of layers of conductor circuits in the thickness direction of the flexible film. According to this manufacturing method, since the thin flexible film is used, it is possible to easily punch holes by punching.
Further, since the conductor circuits are formed on both sides of the flexible film, the conductor circuits can be formed with high density.

Next, in the invention according to claim 6, an insulating adhesive having an opening corresponding to the mounting recess forming portion is adhered to the lower side of the heat dissipation metal plate, and the opening is covered. Then, a first copper foil is adhered to the lower surface side of the insulating adhesive, and then a portion of the first copper foil where conductor circuits and protruding pads are formed is covered with a resist film.
A conductor circuit and a protruding pad are formed on the lower surface side of the insulating adhesive by etching the copper foil, and then the resist film is removed from the heat dissipation metal plate, while at least one surface of the electrically insulating flexible film is formed. A second copper foil is adhered, and then through holes and through holes for forming mounting recesses are formed in the flexible film by punching, and then the second copper foil is etched to form a conductor circuit on at least one surface of the flexible film. Then, the flexible film is adhered to the side of the heat dissipation metal plate on which the conductor circuit and the protruding pad are formed so as to cover the through hole with an insulating adhesive, thereby forming the through hole. A method for manufacturing an electronic component mounting substrate, characterized in that a mounting recess made of a heat dissipation metal plate is formed.

In the invention relating to this manufacturing method, the conductor circuit and the projecting pad formed between the flexible film and the heat dissipation metal plate are formed on the lower surface side of the heat dissipation metal plate. Different from the invention. According to this manufacturing method, since the thin flexible film is used, it is possible to easily punch holes by punching. Further, since the conductor circuit and the protruding pad are provided not only on the surface of the flexible film but also on the lower surface side of the heat dissipation metal plate through the insulating adhesive, high density wiring of the conductor circuit is possible.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 An electronic component mounting board according to an embodiment of the present invention will be described with reference to FIGS. 1 to 11. As shown in FIG. 1, the electronic component mounting substrate 9 of this example is a multilayer substrate 1 including electrically insulating flexible films 11 to 13 and two layers of conductor circuits 31 and 33 provided in the thickness direction of the flexible film. And through holes 110, 120, and 130 penetrating all of the flexible films 11 to 13, and a heat radiating metal plate 2 provided on the upper surface side of the multilayer substrate 1 so as to cover the through holes. The through holes 110, 120, 130 and the heat dissipation metal plate 2 form a mounting recess 10 for mounting the electronic component 8. The multilayer circuit board 1 has a conductor circuit 31
A through hole 17 that is electrically connected to is provided.

Of the above two-layer conductor circuits 31, 33,
One conductor circuit 31 is arranged inside the multilayer substrate 1, and the other conductor circuit 33 is arranged on the lower surface side of the multilayer substrate 1. The two flexible films 1 are provided between the inner conductor circuit 31 and the lower conductor circuit 33.
2 and 13 are provided.

Solder balls 51 and 52 are provided on the opening side of the mounting recess 10 in the multilayer substrate 1. One solder ball 51 is bonded to the lower opening of the through hole 17. The solder ball 51 is connected to the conductor circuit 3 provided inside the multilayer substrate 1 through the through hole 17.
1 and the motherboard 995 are connected. The other solder ball 52 is joined to the conductor circuit 33 provided on the lower surface side of the multilayer substrate 1 and connects the conductor circuit 33 and the mother board 995. Solder balls 51,5
2 is a terminal 996 provided on the surface of the motherboard 995.
It is fusion bonded to 997.

Next, a method of manufacturing the electronic component mounting board 9 will be described with reference to FIGS. First, a flexible film made of epoxy material containing glass fiber is prepared. Flexible film has a thickness of 0.0
It is a flexible strip-shaped film having a width of 5 mm and a width of 2.5 to 15 cm. The flexible film is wound in a roll shape in advance to form a plurality of roll bodies.

Next, while pulling out the flexible film from the roll body, as shown in FIG. 2, an insulating adhesive 62 made of a thermoplastic glass fiber-containing epoxy material is adhered to the lower surface side of the flexible film 11. Then, as shown in FIG. 3, the through hole 1 is formed in the substantially central portion of the flexible film 11 by punching.
Drill 10 Then, on the lower surface side of the flexible film 11, with the insulating adhesive 62 interposed, a thickness of 35 m.
m copper foil 30 is adhered.

Next, as shown in FIG. 4, a conductor circuit 31 is formed from the copper foil by the exposure method and the etching method. Then, the surface of the conductor circuit 31 is coated with a Ni / Au plating film. In this way, the upper layer substrate of the multilayer substrate is obtained.

Next, while pulling out the flexible film from the separate roll body, as shown in FIG. 5, an insulating adhesive made of the same material as the insulating adhesive 62 is provided on the upper surface side and the lower surface side of the flexible film 12, respectively. 63 and 64 are bonded. Next, as shown in FIG. 6, by punching, a through hole 120 is formed substantially in the center of the flexible film 12, and a plurality of holes 121 for forming through holes are formed around the through hole 120. As a result, an intermediate layer substrate of the multilayer substrate is obtained.

Next, while pulling out the flexible film from the separate roll body, as shown in FIG. 7, the insulating adhesive 62 is applied to the lower surface side of the flexible film 13.
An insulative adhesive 65 made of the same material as above is adhered. Then, the flexible film 13 is punched.
A through hole 130 is formed in the substantially central portion of the above, and a plurality of holes 131 for forming through holes are formed around the through hole 130. Next, as shown in FIG. 8, the lower surface side of the flexible film 13 is covered with the copper foil 30.

Next, as shown in FIG. 9, a conductor circuit 33 is formed from the copper foil 30 by an exposure method and an etching method. Then, the surface of the conductor circuit 33 is coated with a Ni / Au plating film. Next, as shown in FIG. 10, the lower surface side of the flexible film 13 is covered with a photosensitive solder mask 66 except for the portions where solder balls are joined. As a result, a lower layer substrate of the multilayer substrate is obtained.

Then, as shown in FIG. 11, the flexible film 11 which is the upper layer substrate, the flexible film 12 which is the intermediate layer substrate, and the flexible film 13 which is the lower layer substrate are laminated and the insulating adhesives 62 to Thermocompression bonding by 64. As a result, the multilayer substrate 1 including three layers is obtained, and the holes 121 and 131 are formed.
Through hole 17 is formed. Next, the heat-dissipating metal plate 2 made of copper and having a thickness of 1.0 mm is thermocompression-bonded to the upper surface side of the multilayer substrate 1 via the insulating adhesive 61. As a result, the mounting recess 10 including the through holes 110, 120, 130 and the heat dissipation metal plate 2 covering the upper surface side thereof is formed.

Then, as shown in FIG. 1, the solder 54 is filled in the through hole 17. Next, the solder balls 51 and 52 are melt-bonded to the lower surface side opening of the through hole 17 and the surface of the conductor circuit 33 provided on the lower surface side of the multilayer substrate 1. As a result, the electronic component mounting board 9 shown in FIG. 1 is obtained.

Thereafter, as shown in FIG. 1, the mounting recess 1 is formed.
0, the electronic component 8 is mounted with an adhesive 69 for die bonding such as silver paste or solder. Next, the electronic component 8 and the tips of the conductor circuits 31 and 33 are connected by a wire 81. Next, the inside of the mounting recess 10 is covered with the sealing resin 6.

Next, the function and effect of the electronic component mounting board will be described. Flexible film 11-13
Is a thin and flexible film. Therefore, when performing the perforating process on the flexible film, the punching can be performed using the punch. The punch has less wear of the cutting edge than the drill, can make many holes in one shot, and has high drilling accuracy. Therefore, the drilling operation is easy and the drilling cost can be reduced.

Further, since the flexible films 11 to 13 are flexible, manufacturing processes such as conductor circuit formation and drilling are successively carried out continuously while being drawn out from a state of being bundled into a roll at the time of manufacturing. be able to. for that reason,
The manufacturing process can be streamlined and simplified.

The upper surface side of the mounting recess 10 is covered with a heat radiating metal plate 2. When the electronic component mounting board 9 is mounted on the motherboard 995, the heat dissipation metal plate 2 is
It is arranged on the side opposite to the side facing the motherboard. Therefore, the heat generated during the operation of the electronic component 8 can be effectively dissipated from above the electronic component mounting board 9 through the heat radiating metal plate 2, and the heat dissipation is high.

A hard heat-dissipating metal plate 2 is coated on the upper surfaces of the flexible films 11 to 13. Therefore, the heat dissipation metal plate 2 can secure the rigidity of the entire electronic component mounting substrate 9. Therefore, the heat-dissipating metal plate 2 can sufficiently supplement the lack of mechanical strength of the flexible films 11 to 13, and improve the mechanical strength and durability of the electronic component mounting board.

Further, two or more conductor circuits 31 and 33 are laminated in the thickness direction of the flexible films 11 to 13. Therefore, the total area of the wirable region is increased, and the conductor circuits can be mounted at high density.

Embodiment 2 As shown in FIG. 12, the electronic component mounting board of this embodiment has a two-layer structure in which two layers of conductor circuits 31 and 33 are formed on the upper surface side and the lower surface side of the flexible film 15. doing.

That is, the electronic component mounting board 90 is provided on the flexible film 15 and on both upper and lower surfaces thereof.
The multi-layer substrate 1 including the conductor circuits 33 and 31 of layers, the through hole 150 penetrating the flexible film 15, and the heat dissipation metal plate 2 provided on the upper surface side of the multi-layer substrate 1 so as to cover the through hole 150 are provided. There is. An insulating adhesive 67 is provided between the conductor circuit 31 and the heat dissipation metal plate 2. The through hole 150 and the heat dissipation metal plate 2 form a mounting recess 10 for mounting the electronic component 8. The multilayer substrate 1 has a through hole 1 which is electrically connected to a conductor circuit 31 provided therein.
8 and 19.

Solder balls 51 and 53 are provided on the opening side of the mounting recess 10 in the multilayer substrate 1. One solder ball 51 connects the through hole 19 and the mother board 995. The other solder ball 53
Connect the conductor circuit 33 and the through hole 18 provided on the lower surface side of the multilayer substrate 1 to the mother board 995. The solder balls 51 and 53 are melt-bonded to the terminals 998 and 999 provided on the surface of the motherboard 995.

Next, a method for manufacturing the electronic component mounting board 9 will be described with reference to FIGS. First,
Similar to the first embodiment, a flexible film roll body is formed. Then, while pulling out the flexible film from the roll body, as shown in FIG. 13, insulating adhesives 68 and 69 made of thermoplastic glass fiber-containing epoxy material are adhered to the upper surface side and the lower surface side of the flexible film 15, respectively. To do. Next, the first copper foil 301 is adhered to the lower surface side of the flexible film 15 via the insulating adhesive 69.

Next, as shown in FIG. 14, by punching, a through hole 150 for forming a mounting recess is formed in the substantially central portion of the flexible film 15, and a through hole 150 is formed.
A plurality of holes 151 for forming through-holes are formed around the circumference. Next, as shown in FIG. 15, the second copper foil 302 is bonded to the upper surface side of the flexible film 15 via the insulating adhesive 68.

Next, using a dry film, a resist film 81 having the same shape as the conductor circuit and the protruding pad is formed on the surfaces of the first and second copper foils 301 and 302. Further, by applying the liquid resist to the lower surface side of the flexible film 15, the inside of the through hole 150 is filled with the liquid resist 89.
It is preferable to coat with. This allows the through hole 1
The etching solution does not come into contact with the lower surface side of the second copper foil 302 that covers the upper side of the 50. Therefore, the protruding pad 310 can be formed in the through hole 150 with high accuracy.

By applying the liquid resist to the upper surface side and the lower surface side of the flexible film 15, the liquid resist 89 is provided inside the through hole 150, and the liquid resist 89 is provided on the surfaces of the first and second copper foils 301 and 302. The resist film 81 can also be formed.

Then, as shown in FIG. 16, the first copper foil is etched to form a conductor circuit 33 on the lower surface side of the flexible film 15. Further, as shown in FIGS. 16 and 20, the second copper foil 302 is etched to form the conductor circuit 31 on the upper surface side of the flexible film, and
A protruding pad 310 connected to the conductor circuit 31 and protruding inward of the through hole 150 is formed. Then, the conductor circuit 3
Ni / Au plated films are applied to the surfaces of the first and second copper foils 310 and 33.

Next, as shown in FIG. 17, the lower surface of the flexible film 15 is covered with a photosensitive solder mask 66 so as to cover the conductor circuit 33. This gives 2
The multilayer substrate 1 in which the conductor circuits 31 and 33 of layers are provided in the thickness direction of the flexible film 15 is obtained.

Next, as shown in FIG. 18, the multilayer substrate 1
The heat radiating metal plate 2 is adhered to the upper surface side of the above through an insulating adhesive 67 made of the same material as the above insulating adhesives 68 and 69. As a result, the mounting recess 10 and the through holes 18 and 19 that open to the lower surface side of the multilayer substrate 1 are formed.
Then, as shown in FIG.
The inside of the is filled with solder 54. Next, through hole 1
Solder balls 53 and 51 are bonded to the lower surface side openings of 8 and 19. As a result, the electronic component mounting board 90 is obtained.

In this example, the conductor circuits 31 and 33 are formed on the upper and lower surfaces of one flexible film. Therefore, a thinner electronic component mounting substrate can be obtained as compared with the case where the conductor circuits are formed on the upper and lower surfaces of the two flexible films in the first embodiment. In addition, in this embodiment, the same effects as those of the first embodiment can be obtained.

Embodiment 3 This embodiment is a method of manufacturing an electronic component mounting board having the same structure as Embodiment 2. In this example, as shown in FIG. 23, the conductor circuit 31 and the protruding pad 310 formed between the flexible film 15 and the heat dissipation metal plate 2 are connected to the heat dissipation metal plate 2.
The difference from the second embodiment in which the conductor circuit 31 is formed on the upper surface side of the flexible film 15 in that it is formed on the lower surface side.

That is, as shown in FIG. 21, the heat dissipation metal plate 2
An opening 67 corresponding to the mounting recess forming portion is formed on the lower surface side of the
An insulative adhesive 67 having 0 is adhered. Next, the first copper foil 3 is formed on the lower surface side of the heat dissipation metal plate 2 so as to cover the entire lower surface side of the heat dissipation metal plate 2 via the insulating adhesive 67.
Bond 01.

Next, as shown in FIG. 22, the first copper foil 30
An electrodeposition resist film 83 is coated on the portions where the conductor circuits and the protruding pads in 1 are formed. At this time, it is preferable that the upper surface side of the heat dissipation metal plate 2 be covered with the dry film resist film 831. As a result, it is possible to prevent the heat dissipation metal plate 2 from being corroded by the etching solution. Next, as shown in FIG. 23, the heat dissipation metal plate 2 is immersed in an etching solution to form the conductor circuit 31 and the protruding pad 310 from the first copper foil. Next, the electrodeposition resist film and the dry film resist film are removed.

On the other hand, as shown in FIG. 24, the conductor circuit 33 is formed on the lower surface side of the flexible film 15. Next, as shown in FIG. 23, the flexible film 1
The heat-dissipating metal plate 2 is bonded to the upper surface side of the insulating film 5 via the insulating adhesive 68, and the projecting pad 310 is formed to project from the opening 150 provided in the flexible film 15. As a result, the electronic component mounting board 90 similar to that of the second embodiment is obtained (see FIG. 12). Others are the same as the second embodiment.

In this example, as shown in FIGS. 22 and 23, the conductor circuit 31 and the protruding pad 310 are formed by using the electrodeposition resist film 83. Electrodeposition resist film 83
Since it is easy to control the film thickness, it is possible to cover the conductor circuit and the portion where the protruding pad is formed with a uniform thickness. Therefore, the etching accuracy of the copper foil can be increased.

Of the two layers of conductor circuits in the electronic component mounting board, one conductor circuit 31 is on the lower surface side of the heat dissipation metal plate 2, and the other conductor circuit 33 is the flexible film 15.
Is formed on the upper surface side of. Therefore, both conductor circuits can be formed in parallel, and the manufacturing process of the electronic component mounting board can be speeded up.

In this example, the electrodeposition resist film is used, but as shown in FIGS. 25 and 26, the dry film resist film 84 may be used to form the conductor circuit and the protruding pad. In this case, as shown in FIG. 25, the opening 670 of the insulating adhesive 67 is formed in the first copper foil 301.
It is preferable to provide it inside the protruding pad forming portion 311 of FIG. This is because it is possible to prevent the etching solution from eroding the protruding pad forming portion 311 of the first copper foil from its upper surface side. When the heat-dissipating metal plate 2 is immersed in the etching solution with the dry film resist film 84 formed as described above, the protruding pad 310 is formed outside the opening 670 of the insulating adhesive 67 as shown in FIG. .

[0058]

According to the present invention, it is possible to provide a board for mounting electronic parts and a method of manufacturing the same, which is excellent in heat dissipation, can be easily drilled, and allows high-density wiring. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electronic component mounting board in which an electronic component is mounted in a mounting recess according to the first embodiment.

FIG. 2 is a cross-sectional view of a flexible film showing a method for manufacturing an upper layer substrate in the first embodiment.

FIG. 3 is a cross-sectional view of the flexible film having a through hole formed, following FIG.

FIG. 4 is a cross-sectional view of the upper substrate subsequent to FIG.

FIG. 5 is a cross-sectional view of a flexible film showing a method for manufacturing an intermediate-layer substrate in the first embodiment.

FIG. 6 is a cross-sectional view of the intermediate layer substrate following FIG.

FIG. 7 is a cross-sectional view of a flexible film showing the method for manufacturing the lower layer substrate in the first embodiment.

FIG. 8 is a cross-sectional view of the flexible film having copper foil adhered to the lower surface side, following FIG.

9 is a cross-sectional view of the flexible film on which a conductor circuit is formed, following FIG.

10 is a cross-sectional view of the lower substrate, which is subsequent to FIG.

FIG. 11 is a cross-sectional view of an electronic component mounting substrate including an upper layer substrate, an intermediate layer substrate, a lower layer substrate, and a heat dissipation metal plate in the first embodiment.

FIG. 12 is a cross-sectional view of an electronic component mounting board in which an electronic component is mounted in a mounting recess according to the second embodiment.

FIG. 13 is a cross-sectional view of a flexible film showing a method for manufacturing an electronic component mounting substrate according to the second embodiment.

14 is a cross-sectional view of the flexible film having a through hole formed, following FIG.

FIG. 15 is a cross-sectional view of a flexible film having a copper foil adhered to the upper surface side, following FIG.

16 is a cross-sectional view of the flexible film on which a conductor circuit and protruding pads are formed following FIG.

FIG. 17 is a cross-sectional view of the flexible film on which a photosensitive solder mask is formed, following FIG. 16.

FIG. 18 is a cross-sectional view of the flexible film following FIG. 17, in which a heat dissipation metal plate is bonded to the upper surface side.

FIG. 19 is a cross-sectional view of the electronic component mounting board according to the second embodiment.

FIG. 20 is a plan view of a main part of a flexible film having a conductor circuit and protruding pads according to the second embodiment.

FIG. 21 is a cross-sectional view of a heat dissipation metal plate having a lower surface side covered with a first copper foil in the third embodiment.

FIG. 22 is a cross-sectional view of a heat dissipation metal plate in which a first copper foil is covered with an electrodeposition resist film in the third embodiment.

FIG. 23 is a cross-sectional view of a heat dissipation metal plate in which a conductor circuit and protruding pads are formed on the lower surface side in the third embodiment.

FIG. 24 is a sectional view of a flexible film in which a conductor circuit is formed on the lower surface side in the third embodiment.

FIG. 25 is a sectional view of a heat dissipation metal plate in which a first copper foil is covered with a dry film resist film according to the third embodiment.

FIG. 26 is a cross-sectional view of a heat dissipation metal plate having a conductor circuit formed by using a dry film resist film and a protruding pad according to the third embodiment.

FIG. 27 is a cross-sectional view of an electronic component mounting board in a conventional example.

[Explanation of symbols]

 1. . . 9. multilayer substrate; . . Mounting recess, 11, 12, 13, 15. . . Flexible film, 17, 18, 19. . . Through hole, 110, 120, 130, 150. . . Through holes, 121, 131, 151. . . Hole, 2. . . Heat dissipation metal plate, 31, 33. . . Conductor circuit, 310. . . Protruding pad, 51, 52, 53. . . Solder balls, 54. . . Solder, 61-68. . . Insulating adhesive, 66. . . 7. Photosensitive solder mask, 8. . . Electronic components, 9, 90. . . Substrate for mounting electronic parts, 995. . . Motherboard,

Claims (6)

[Claims] 1. A multilayer substrate comprising at least one electrically insulating flexible film, a conductor circuit having two or more layers in the thickness direction of the flexible film, and a through hole penetrating all of the flexible film. A heat dissipation metal plate provided on the upper surface side of the multilayer substrate so as to cover the through hole, a mounting recess for mounting an electronic component formed by the through hole and the heat dissipation metal plate, and provided on the multilayer substrate. A board for mounting electronic parts, comprising: a through hole that is electrically connected to the conductor circuit. 2. The electronic component mounting substrate according to claim 1, wherein the flexible film has a thickness of 30 to 200 μm. 3. The electronic component mounting substrate according to claim 1, wherein the heat dissipation metal plate has a thickness of 50 to 1500 μm. 4. The method according to claim 1, wherein
The electronic component mounting board is provided with a connecting means for connecting a conductor circuit and a mother board on the opening side of the mounting recess. 5. A first copper foil is adhered to one side of an electrically insulating flexible film, and then punched to form a through hole for forming a mounting recess in the flexible film.
And through holes are formed, and then a second copper foil is bonded to the other surface of the flexible film opposite to the bonding surface of the first copper foil so as to close the through hole, and then the first copper foil is bonded. The copper foil is etched to form a conductor circuit on one side of the flexible film.
The copper foil is etched to form a conductor circuit on the other side of the flexible film, and a protruding pad connected to the conductor circuit and protruding inward of the through hole is formed.
Then, a heat dissipation metal plate is adhered to the side of the flexible film on which the protruding pad is formed so as to cover the through hole via an insulating adhesive, so that the through hole and the heat dissipation metal plate are mounted. A method of manufacturing an electronic component mounting substrate, characterized in that a recess is formed. 6. An insulating adhesive having an opening corresponding to the mounting recess forming portion is adhered to the lower side of the heat dissipation metal plate, and the lower surface of the insulating adhesive is covered so as to cover the opening. Then, a first copper foil is bonded to the first copper foil, and then a resist film is coated on a portion of the first copper foil where the conductor circuit and the protruding pad are formed. Forming a conductive circuit and a protruding pad on the side, then removing the resist film from the heat-dissipating metal plate, while adhering a second copper foil to at least one side of an electrically insulating flexible film, and then punching the above. Through holes and through holes for forming mounting recesses are formed in the flexible film, and then the second copper foil is etched to form a conductor circuit on at least one surface of the flexible film. Next, the flexible film is adhered to the side of the heat dissipation metal plate on which the conductor circuit and the protruding pad are formed so as to cover the through hole with an insulating adhesive, thereby forming the through hole and the heat dissipation metal plate. A method for manufacturing an electronic component mounting substrate, characterized in that a mounting recess made of is formed.