JPH09331132A - Circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a circuit board, which can obtain conditions such as the conditions of a high-density mounting, lightweight and low cost, and the condition to satisfy prescribed properties. SOLUTION: Different circuit boards 12 (12a, 12b and 12c) with necessary parts and components are mounted on a circuit board 11 to realize special characteristics, which can not be realized by mounting parts and components on the board 11. As a method of mounting the boards 12 on the board 11, there is a method of mounting the boards 12 using bumps and a conductive bonding agent, or a method of mounting the boards 12 using a bump technique such as a transfer bump technique. After the boards 12 are mounted on the board 11, passive circuit components 13a to 13c, active circuit components 14a to 14c and ICs 15a and 15b are mounted on the board 11 and the boards 12a and 12b by a reflow soldering method or the like. Alternatively, after one part or the whole electronic components is mounted on the respective boards 12, the boards 12 are mounted on the board 11 using bumps and a conductive bonding agent, or the boards 12 are mounted on the board 11 by a bump technique such as a transfer bump technique.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board for forming an electronic circuit by mounting passive circuit components such as resistance elements, capacitance elements, and inductance elements, and active circuit components such as transistors and ICs.

[0002]

2. Description of the Related Art In recent years, in multimedia equipment such as communication equipment such as mobile phones and PHS, information equipment such as computers and electronic notebooks, there is a strong demand in the market for reduction in size, weight, and size. Various technologies have been developed in many fields, such as reduction in size and weight of batteries and IC of electronic circuits. The miniaturization of electronic circuits, which is the heart of these devices, is one of the most important technologies, and attention is focused on high-density mounting of these electronic circuits as well as the miniaturization of various electronic components. . In particular, the circuit board is attracting attention because it is one pillar for high-density mounting.

A conventional circuit board will be described below with reference to the drawings. FIG. 5 shows an example of a conventional circuit board and its component mounting. In FIG.
Is a circuit board made of resin, 32a, 32b and 32c are passive circuit components such as resistance elements, capacitance elements and inductance elements, and 33a, 33b and 33c are active circuit components such as transistors and diodes, and 34
Reference numerals a and 34b are ICs, and reference numerals 35a and 35b are modules such as power amplifiers, VCOs and TCXOs.

A circuit board for constructing an electronic circuit is required to have characteristics such as high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics depending on the type of circuit or the environment in which it is used. However, in the conventional circuit, as shown in FIG. 5, passive circuit components 32a, 32b,
32c, active circuit components 33a, 33b, 33c, IC3
4a and 34b are mounted, and especially the circuit part that is required to have high-frequency characteristics and power characteristics that cannot be mounted on the circuit board is
A circuit is configured by modularizing and mounting the modules 35a and 35b on the circuit board 31.

For example, in a conventional power circuit, the circuit board 31
When a resin substrate is used as a substrate, the resin substrate cannot achieve power resistance, voltage resistance, heat resistance, etc., so power amplifier, voltage resistance, heat resistance, etc. Was modularized and mounted on the resin circuit board 31 to realize initial characteristics and reliability characteristics. In the conventional high frequency circuit, the circuit board 31
When a resin substrate is used as, the resin substrate cannot realize high-frequency characteristics, moisture resistance, etc.
High frequency circuits such as CXO, VCO and synthesizer were modularized and mounted on a resin circuit board to achieve initial characteristics and reliability characteristics.

Further, as the circuit board 31, a ceramic board or a enamel-processed metal board capable of realizing characteristics such as electric power resistance, voltage resistance, and heat resistance is used to mount all electronic components. And configured an electronic circuit. Further, as the circuit board 31, a ceramic board capable of realizing characteristics such as high frequency characteristics and moisture resistance is used, and all electronic components are mounted to form a circuit.

[0007]

However, when an electronic circuit is constructed using a resin circuit board, high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics are required when mounting on a resin circuit board. The electronic circuit is configured by modularizing only the circuit portion where it is difficult to realize the required characteristics such as the above and mounting it on the resin circuit board. Therefore, there are problems that the circuit area is large, high-density mounting is difficult, the weight is large, it is difficult to reduce the height, and the cost is high.

Further, in the conventional electronic circuit in which all electronic components are mounted on one substrate, the high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics, etc. of the electronic circuit are In order to satisfy the characteristics of the circuit board, the circuit board is used that satisfies all the required characteristics such as high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics in accordance with the purpose of use. . For example, a ceramic substrate is used in a high frequency circuit because a substrate having excellent frequency characteristics and excellent moisture resistance is required, and a ceramic substrate or a enamel-processed metal substrate is used in a power circuit. Therefore, there are problems that it is difficult to mount electronic components on a circuit board at high density, the weight becomes large, it is difficult to reduce the height, and the cost becomes high.

The object of the present invention is to realize high-density mounting, small weight, low profile, low cost,
In addition, high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics,
An object of the present invention is to provide a circuit board that can satisfy characteristics such as heat resistance.

[0010]

A first circuit board of the present invention constitutes an electronic circuit by mounting passive circuit components such as resistance elements, capacitance elements, and inductance elements, and active circuit components such as transistors and ICs. Circuit board,
A circuit board is configured by electrically connecting at least one of a second resin substrate, a ceramic substrate, and a metal substrate, which are different in type from the resin substrate, and mounted on the resin substrate.
For the circuit part with good normal characteristics, the circuit parts are mounted on a resin substrate to form an electronic circuit, and when high-frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics, etc. are required, The resin substrate is made of bakelite, glass epoxy, etc. by mounting circuit components on the circuit substrate having the required characteristics among the resin substrate, ceramic substrate, metal substrate, etc. A low-cost, lightweight circuit board can be used, and high-density mounting is possible. Also, by selecting a circuit board that can satisfy the characteristics such as high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics, high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics Characteristics such as characteristics can be easily realized. That is, it is possible to provide a circuit board that can realize an electronic circuit having excellent characteristics at low cost.

A second circuit board according to the present invention is a circuit board for forming an electronic circuit by mounting passive circuit parts such as resistance elements, capacitance elements and inductance elements, and active circuit parts such as transistors and ICs. A circuit board is constructed by integrating a resin board and at least one of a second resin board or a ceramic board of a different type from the resin board, and a metal board, and a circuit part having good normal characteristics is made of resin. An electronic circuit is constructed by mounting circuit components on the board.
When characteristics such as high-frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics are required, on the circuit board section that has the required characteristics of the second resin substrate, ceramic substrate, metal substrate, etc. By constructing an electronic circuit by mounting circuit components on, a low-cost and lightweight circuit board such as bakelite or glass epoxy can be used as the resin board,
Also, high-density mounting is possible. In addition, by selecting the circuit board that can satisfy the characteristics such as high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics, high frequency characteristics, power resistance characteristics, humidity resistance characteristics, temperature characteristics, heat resistance characteristics Characteristics such as characteristics can be easily realized. That is,
It is possible to provide a circuit board that can realize an electronic circuit having excellent characteristics at low cost.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a perspective view of an electronic circuit including a circuit board according to a first embodiment of the present invention.

In the figure, reference numeral 11 is a main circuit board made of epoxy-based or phenol-based resin.
Reference numerals 2b and 12c are circuit boards made of a material different from that of the circuit board 11 and having different characteristics, for example, a circuit board made of ceramic such as alumina or enamel-processed metal, or resin such as polyimide series or Teflon series. . Further, 13a, 13b and 13c are passive circuit components such as resistance elements, capacitance elements and inductance elements, 14a, 14b and 14c are active circuit components such as transistors and diodes, and 15a and 15b are ICs.
It is.

As the circuit board 11, a low-cost epoxy-based multilayer circuit board using a technique such as a via hole is used when realizing high-density mounting, and a phenol-based circuit board is used when realizing low cost. Therefore, a circuit board made of another material is used. The electronic circuit is required to have characteristics such as high frequency characteristics, electric power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics depending on the type or use environment. If these characteristics are to be realized only by the circuit board 11, a high-performance board such as ceramic is required as the circuit board. However, a substrate made of ceramic or the like is expensive and it is difficult to mount it at high density. Therefore, in the first embodiment, the circuit board 11
Only the circuit portion that requires special characteristics that cannot be realized by mounting another circuit board 12 on the circuit board 11 and mounting the component on the circuit board 11 mounts the component on the circuit board 12. Achieve required characteristics. As a method of mounting the circuit board 12 on the circuit board 11 by electrically connecting it,
Since the number of connections is reduced by soldering and the height is increased with a connector, the number of connections is also reduced. Therefore, bumps are formed directly on the electrodes of the IC chip by wire bonding or the like (bumps having two steps of protrusions are preferable). A method of mounting using a conductive adhesive and a method of mounting using a bump technique such as a transfer bump are effective. as a result,
Even if the area of the circuit board 12 is reduced, the number of connections with the circuit board 11 can be increased and the height can be reduced.

After mounting the circuit board 12 on the circuit board 11, the passive circuit component 13 is formed as in the case of a normal circuit board.
a, 13b, 13c, active circuit components 14a, 14b, 1
4c, ICs 15a, 15b can be mounted by reflow soldering or the like, and after mounting some or all of the electronic components on the circuit board 12, the bumps (preferably bumps with two steps) and a conductive adhesive Alternatively, it can be mounted on the circuit board 11 by a bump technique such as a transfer bump technique. In either case, high density mounting and low profile can be achieved in a small area.

An example of a circuit partially including a power circuit is shown in FIG. In the figure, 11 is a main circuit board made of an epoxy-based or phenol-based resin, and 12a and 12b are circuit boards made of a ceramic such as alumina or a enamel-processed metal having excellent power resistance characteristics. . Further, 13a, 13b and 13c are passive circuit components such as resistance elements, capacitance elements and inductance elements, 14a, 14b and 14c are active circuit components such as transistors and diodes, and 15a and 15b are ICs. In other words, with a resin board,
Since heat resistance and the like cannot be realized, circuit boards 12a, 12 made of ceramic or enamel-processed are used.
The bumps (preferably bumps having two steps) and the conductive adhesive are mounted on the circuit board 11 as b.
Alternatively, mounting is performed by a bumping technique such as transfer bumping, and a power circuit portion having a problem in power resistance characteristics, withstand voltage characteristics, heat resistance, etc. is formed on the circuit board 12.

Further, in a circuit example including a high frequency circuit in part,
A ceramic circuit board with excellent high-frequency characteristics and moisture resistance is mounted on the circuit board using the bumps (preferably bumps with two-step protrusions) and a conductive adhesive, or by a bumping technique such as transfer bumping. And then TCX on this
A high frequency circuit such as an O, VCO, and synthesizer section can be configured to realize initial characteristics and reliability characteristics of the entire electronic circuit.

(Second Embodiment) FIG. 3 is a perspective view of an electronic circuit including a circuit board according to a second embodiment of the present invention.

In the figure, 21 is a main circuit board made of epoxy resin or phenol resin, and 22a, 2
Reference numerals 2b and 22c are circuit boards made of a material different from that of the circuit board 21 and having different characteristics, for example, ceramics such as alumina or enamel-processed metal, or resin such as polyimide-based or Teflon-based resin. . Reference numerals 23a, 23b and 23c are passive circuit components such as resistance elements, capacitance elements and inductance elements, 24a, 24b and 24c are active circuit components such as transistors and diodes, and 25a and 25b are ICs.
It is.

As the circuit board 21, a low-cost epoxy-based multilayer circuit board using a technique such as a via hole is used when realizing high-density mounting, and a phenol-based circuit board is used when realizing low cost. Therefore, a circuit board made of another material is used. The electronic circuit is required to have characteristics such as high frequency characteristics, electric power resistance characteristics, humidity resistance characteristics, temperature characteristics, and heat resistance characteristics depending on the type or use environment. If these characteristics are to be realized only by the circuit board 21, a high-performance board such as ceramic is required as the circuit board. However, a substrate made of ceramic or the like is expensive and it is difficult to mount it at high density. Therefore, in the second embodiment, the circuit board 21
And another circuit board 22 are integrated to form a circuit board,
Only parts of the circuit that require special characteristics that cannot be realized by mounting the components on the circuit board 21 are mounted on the circuit board 22 to realize the required characteristics. As a method of integrating the circuit board 21 and the circuit board 22, the circuit board 21 is integrally molded together with the circuit board 22. As a result, the passive circuit components 23 are
a, 23b, 23c, active circuit components 24a, 24b, 2
4c, ICs 25a, 25b can be mounted by reflow soldering or the like, and high density mounting and low profile can be achieved in a small area.

An example of a circuit partially including a power circuit is shown in FIG. In the figure, reference numeral 21 is a main circuit board made of an epoxy-based or phenol-based resin, and 22a and 22b are circuit boards made of a ceramic such as alumina or a enamel-processed metal having an excellent power resistance characteristic. . Further, 23a, 23b and 23c are passive circuit components such as resistance elements, capacitance elements and inductance elements, 24a, 24b and 24c are active circuit components such as transistors and diodes, and 25a and 25b are ICs. In other words, with a resin board,
Since heat resistance and the like cannot be realized, the circuit board 22a, 22
It is adopted as b and integrally molded with the circuit board 21,
On the circuit board 22, a power circuit section having problems such as power resistance characteristics, withstand voltage characteristics, and heat resistance is formed.

Further, in a circuit example including a high frequency circuit in part,
A circuit board made of a ceramic board excellent in high frequency characteristics and moisture resistance is integrally molded on the circuit board, and a high frequency circuit such as a TCXO, VCO, synthesizer section is formed on the circuit board section made of the ceramic board. The initial characteristics and reliability characteristics of the entire electronic circuit can be realized.

As described above, according to the present invention, as described in the first embodiment, the bumps (preferably the bumps having the two-step protrusions) and the conductive adhesive are mounted, or the bumping technique such as transfer bumping is used. Therefore, by mounting another circuit board on the circuit board and mounting the components on the circuit board, the components that require special characteristics that cannot be realized cannot be mounted on the other circuit board. By realizing the required characteristics by mounting, it is possible to realize low cost, excellent characteristics, high density mounting, and low profile.

Further, according to the present invention, as shown in the second embodiment, by forming another circuit board integrally on the circuit board, it is possible to realize a special case which cannot be realized by mounting components on the circuit board. Only the circuit parts that require characteristics can be mounted at a low cost by realizing the required characteristics by mounting the components on another circuit board, enabling high-density mounting, low profile, etc. To do.

[0026]

As described above, according to the present invention, various characteristics such as initial characteristics and reliability characteristics required for electronic circuits can be satisfied, and further, low cost, high-density mounting and small weight can be achieved. It is possible to provide a circuit board whose height can be easily reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of an electronic circuit using a circuit board according to a first embodiment of the present invention.

FIG. 2 is a perspective view when the first embodiment shown in FIG. 1 is applied to a power circuit.

FIG. 3 is a perspective view of an electronic circuit using a circuit board according to a second embodiment of the present invention.

FIG. 4 is a perspective view when the second embodiment shown in FIG. 3 is applied to a power circuit.

FIG. 5 is a perspective view of an electronic circuit using a conventional circuit board.

[Explanation of symbols]

 11, 21 Circuit board 12, 22 Circuit board 13, 23 Passive component 14, 24 Active component 15, 25 IC

Claims (3)

[Claims] 1. A circuit board for forming an electronic circuit by mounting a passive circuit component such as a resistance element, a capacitance element and an inductance element, and an active circuit component such as a transistor and an IC, wherein the resin is formed on a resin substrate. A composite circuit board is configured by electrically connecting and mounting at least one of a second resin substrate, a ceramic substrate, and a metal substrate different in type from the resin substrate and the resin substrate and the second substrate. A circuit board, wherein the circuit component is mounted on at least one of a resin board, the ceramic board, and the metal board. 2. A circuit board for forming an electronic circuit by mounting a passive circuit component such as a resistance element, a capacitance element and an inductance element, and an active circuit component such as a transistor and an IC, wherein the resin is provided on a resin substrate. A circuit board is configured by electrically connecting at least one of a second resin substrate, a ceramic substrate, and a metal substrate of different types to the resin substrate to form a circuit board. Resin board,
A circuit board, wherein the circuit component is mounted on at least one of the ceramic board and the metal board. 3. A circuit board on which an electronic circuit is constructed by mounting passive circuit parts such as a resistance element, a capacitance element, an inductance element, etc., and an active circuit part such as a transistor, an IC, etc., wherein the resin is formed on a resin board. A circuit board is formed by integrating at least one of a second resin substrate, a ceramic substrate, and a metal substrate, which are different in type from the resin substrate, the resin substrate, the second resin substrate, and the ceramic substrate. A circuit board, wherein the circuit component is mounted on at least one of a board and the metal board.