JPH10335873A - High-frequency circuit component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-frequency circuit component which is superior in mass-productivity and is highly reliable in joint between a dielectric circuit board and a lid body. SOLUTION: This high-frequency circuit component is obtained by covering a circuit board 1, with wiring conductors 11, 12 and electronic components 13 formed thereon, with a metal lid body 2 which is rectangular parallelopiped in form. The circuit board 1 has the wiring conductor 11 as grounding potential extending along the periphery of its surface. A lid body 2 is placed on the circuit board 1, and has jointing pieces 3 formed on its sides. The jointing pieces 3 protrude inwards and have a notched portion 31 at their center which reduces the width of the jointing pieces. The exterior face of the jointing pieces 3 and the wiring conductor 11 as grounding potential are connected with each other through conductive adhesive 4 in triangular recesses X, formed by the jointing pieces 3 of the lid body 2 and the surface of the circuit board 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency circuit component including a resonance circuit and an oscillation circuit operating in a high frequency range, and more particularly to a joining structure of a metal cover.

[0002]

2. Description of the Related Art In an electronic component including a resonance circuit and an oscillation circuit operating in a high frequency region, a predetermined circuit board is shielded to cut off an external noise signal and a noise signal from the component and reduce a stray capacitance component. It is known to cover with a lid that has an effect.

For example, in the oscillator (high-frequency circuit component) disclosed in Japanese Patent Application Laid-Open No. 4-328903, a rectangular circuit board on which a strip line (conductor forming a resonance circuit) is formed is covered with a shield lid. Specifically, an electrode of a ground potential is formed on one end face of the rectangular circuit board, and four side faces of the shield lid are covered and arranged so as to abut against the four end faces of the rectangular circuit board, respectively. Conventionally, a conductive adhesive such as solder is connected between a ground potential electrode formed on one end surface of the circuit board and a side surface of the shield lid.

[0004]

The above-described high-frequency circuit component has a structure that is very unsuitable for mass production.

That is, a circuit board is prepared by using a large circuit board from which a plurality of components can be extracted, and a plurality of circuit boards are collectively prepared and divided into individual circuit boards. Because the shield lid is joined to the end surface of the circuit board, at least the coating of this shield lid is
It is necessary to perform the process after dividing the large circuit board into individual circuit boards. That is, it is performed for each circuit board.

At the same time, the connection between the lid having the shielding effect and the ground potential wiring electrode is made at the end face of the circuit board, so that the circuit board and the shield lid are mechanically joined and the ground potential wiring is connected. It is necessary to apply or supply a conductive adhesive such as solder for making an electrical connection between the electrode and the shield lid between the end surface of the circuit board and the inner surface of the shield lid. Or upon supply,
It was necessary to align the end surface of the circuit board with the upper surface.

Further, in the above-described high-frequency circuit component, the connection reliability between the shield lid and the wiring electrode of the ground potential of the circuit board is low. That is, stable connection between the inner surface of the shield case and the end surface (outer peripheral surface) of the circuit board cannot be visually confirmed. In addition, for example, when the amount of applied or supplied solder, which is a conductive adhesive, is excessive, melting of the solder may spread to the inner surface of the shield lid, causing a short circuit with a wiring conductor other than the ground potential. Or the generation of a stray capacitance component.

The present invention has been made in view of the above-mentioned problems, and has as its object to provide a high frequency device which is excellent in mass productivity, can visually confirm bonding by a conductive adhesive, and can greatly improve bonding reliability. It is to provide a circuit component.

[0009]

According to the present invention, a circuit board made of a ceramic or organic resin material and having a wiring conductor and various electronic components formed on a surface thereof is coated with the wiring conductor and the electronic component. In a high-frequency circuit component formed by joining a substantially rectangular parallelepiped metal lid to the circuit board, a ground potential wiring conductor is formed on the outer periphery of the surface of the circuit board, and the lid protrudes inward on the side surface, and A joining piece having a cut-out portion for reducing the width is formed at the center, and the lid and the circuit board are recessed between the joining piece of the lid and the ground potential wiring conductor of the circuit board. A high-frequency circuit component characterized by being joined by a conductive adhesive disposed therein.

[0010]

The metal lid mounted on the circuit board of the present invention and having a shielding effect has a plane shape slightly smaller than the plane shape of the circuit board, and is placed on the surface of the circuit board. ing. That is, even in the case of manufacturing a circuit board using a large circuit board from which a plurality of circuit boards can be extracted, each circuit board area can be covered with a lid before the large circuit board is divided and bonded. By dividing the large circuit board, high-frequency circuit components can be achieved immediately. That is, it can be said that this is a high-frequency circuit component having extremely excellent mass productivity.

Further, the joining between the circuit board and the lid is performed in a recess formed by the ground potential wiring conductor extending on the outer periphery of the circuit board and the joining piece projecting inward on the side surface of the lid. . That is, since the conductive adhesive is bonded between the wiring conductor of the ground potential extending to the outer periphery of the circuit board and the outer surface of the bonding piece of the lid, the bonding state can be easily confirmed visually.
In addition, the conductive adhesive supplied to the outer surface of the joint piece can be effectively prevented from spreading and spreading inside the case, and short circuit with a predetermined wiring conductor of a circuit board and generation of a stray capacitance component can be suppressed. And a bonding structure with extremely stable characteristics can be obtained.

Further, since the notch portion for reducing the width is formed in the joining piece, even if the conductive adhesive applied to the outer surface of the joining piece tries to spread along the outer surface of the joining piece, it is not removed. It is possible to keep the conductive adhesive in the above-mentioned depressions that can be suppressed and sufficient to achieve a secure bonding.

Further, in a state where the conductive adhesive is supplied excessively, the notch portion is filled up, so that a part whose bonding state is unstable can be excluded before the characteristic inspection.

As a result, a high-frequency circuit component excellent in mass productivity and having extremely high joining reliability between the circuit board and the lid is obtained.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A high-frequency circuit component according to the present invention will be described below with reference to the drawings.

FIG. 1 is an external perspective view of a high-frequency circuit component according to the present invention, and FIG. 2 is a sectional view taken along line AA in FIG.

In the figure, 1 is a circuit board, 2 is a metal lid, and 3 is a joint piece.

The circuit board 1 is formed on a rectangular dielectric substrate 10 made of a ceramic such as alumina or barium titanate, or an organic resin material such as glass-ceramic or glass-epoxy, and a surface of the dielectric substrate 10. A wiring conductor 11 having a ground potential, other wiring conductors 12, and various electronic components 13. Here, the other wiring conductors 12 are the dielectric substrate 10 in the lid of the dielectric substrate 10.
, A signal line terminal electrode formed on an end face of the dielectric substrate 10, and the like.

The circuit board 1 operates as an oscillation circuit that derives a high-frequency signal, a resonance circuit that resonates at a predetermined frequency, a filter circuit that extracts only a signal component of a predetermined frequency, and the like. It should be noted that the dielectric substrate 10 can be laminated, and a strip line or various wiring conductors can be formed in the inner layer.

Such a circuit board 1 is formed using a large circuit board from which a plurality of components can be extracted. Each of the wiring conductors 11 and 12 is formed of a conductive material mainly composed of Ag or Cu which can be soldered.

Here, the connection conductor 11 of the wiring conductor 11 of the ground potential partially extends at least to the vicinity of the outer periphery of the circuit board 1 and is mechanically connected to the lid 2 and electrically connected thereto. It has become.

The metal lid 2 is made of, for example, phosphor bronze or nickel silver plated with Sn, Ni, Cu, Zn or an alloy thereof, which can be soldered to at least the surface thereof. A rectangular parallelepiped having a rectangular shape slightly smaller than the rectangular circuit board 1 is formed, and one surface of the bottom surface is open. That is, it is composed of four side surfaces 21 to 24 and an upper surface 25. In addition, the lower end of the side surface 22 is not short-circuited with another wiring conductor 12 such as a signal-side terminal electrode.
A recess 26 is formed. The above four sides 21
Out of 24, a plurality of sides, for example, all four sides,
A joining piece 3 for joining to a wiring conductor 11 at the ground potential on the surface of the circuit board 1 is formed.

The joining piece 3 is bent at a substantially central portion of each of the side surfaces 21 to 24 of the lid 2 so as to project inward with a width of, for example, about 5 to 20 mm. The lower end of the joining piece 3 projecting inward is substantially connected to each side surface 21 of the lid 2.
-24 are set at substantially the same height as the lower ends of.

Near the center of the joining piece 3 in the height direction, a notch 31 such as a through hole having a width of about 1/2 of the width of the joining piece 3 is formed.

The cover 2 having such a joint piece 3 is placed on the surface of the circuit board 1 so as to cover the wiring conductors 12 for signals and the like and various electronic components 13 on the surface of the circuit board 1, and Electrically connected and joined by the conductive adhesive 4.

Specifically, the cover 2 is provided on the surface of the circuit board 1.
Is placed such that the joint piece 3 of the lid 2 is positioned on the wiring conductor 11 at the ground potential of the circuit board 1. As a result, a triangular depression X is formed between the joint piece 3 protruding into the lid 2 and the wiring conductor 11 of the circuit board 1.
Then, the wiring conductor 11 (bonding pad) of the ground potential that extends from the recess X to the outer periphery of the surface of the circuit board 1 appears. Then, a conductive adhesive material 4 such as solder is supplied between the wiring conductor 11 of the circuit board 1 in the depression X and the outer surface of the joining piece 3 by a dispenser or the like, and is cured and joined. The lid 2 is joined at a plurality of locations on the surface of the circuit board 1,
One of the joints is electrically connected to the wiring conductor 11 at the ground potential, whereby a shielding effect can be obtained.

As described above, since the conductive adhesive 4 is joined between the wiring conductor 11 of the ground potential extending around the outer periphery of the surface of the circuit board 1 and the outer surface of the joining piece 3 of the lid 2, The joined state can be easily confirmed visually.

Further, for example, even if the solder supplied to the outer surface of the joint piece 3 is melted and spread by the application of heat, or spreads on the outer surface of the joint piece 3, it does not substantially spread inside. Therefore, it is possible to effectively suppress a short circuit with the predetermined wiring conductor 12 of the circuit board 1 and generation of a stray capacitance component,
A junction structure with very stable characteristics is obtained.

The joining piece 3 is formed with a notch 31 such as a through hole for reducing the width of the joining piece 3. For this reason, even if the conductive adhesive 4 supplied to the outer surface side of the joining piece 3 tries to spread along the outer surface of the joining piece 3, the spread is suppressed, and the joining piece 3 and the circuit board 1 It is possible to maintain sufficient and reliable solder for bonding between the wiring conductors 11 (connection pads) at the ground potential.

Further, since the inside of the lid 2 near the joint can be visually observed through the cutout portion 31 such as a through hole, the above-described short-circuit state between the predetermined wiring conductor 12 and the conductive adhesive 4 can be checked. It can also be determined visually.

Further, in a bonding state in which the conductive adhesive material 4 such as solder is likely to flow into the inner surface of the case 2 due to excessive supply of the conductive adhesive material 4, the cut-out portion 31 of the through-hole is connected to the conductive adhesive material. Since the material 4 spreads over the outer surface of the joint piece 3 so as to close the conductive material 4, the conductive adhesive 4 adheres to the notch 31.
Can be inferred to some extent by observing (visual appearance inspection) the characteristic inspection can be performed very easily and efficiently.

In addition, the lid 2 mounted on the circuit board 1
Has a plane shape slightly smaller than the plane shape of the circuit board 1, and is mounted on the surface of the circuit board 1.
That is, the lid 2 is disposed at a position where it enters the inside from the outer peripheral edge of the circuit board 1.

As a result, mass productivity can be significantly improved in the manufacturing process. This is a step of placing and joining the lid 2
This is because it can be incorporated into the process of making a circuit board with a large circuit board.As in the past, the large circuit board is divided into individual circuit boards, the circuit boards are aligned, and a conductive adhesive is applied. There is no need to join the lid every time.

FIG. 3 is a process flow chart for explaining a method of manufacturing a high-frequency circuit component according to the present invention.

First, a large circuit board is formed.

In this step, the wiring conductor 1 is provided for each circuit board area of the large circuit board from which a plurality of circuit board areas can be extracted.
1 and 12 and electronic components 13 are mounted.

Next, a lid is bonded to each circuit board.

In this step, the lids 2 are placed for each circuit board on the surface of a large circuit board composed of a plurality of circuit board regions having the same configuration as the circuit board 1, and the lids 2 adjacent to each other are placed.
Using a gap between the two, a triangular depression X composed of a joint piece 3 protruding inside the lid 2 and a wiring conductor 11 for each circuit board of a large circuit board, creamy solder or the like by a dispenser or the like. Is supplied and heat-treated,
The large circuit board and the lid 2 are firmly mechanically joined to each other, and at the same time, the wiring conductor 11 at the ground potential formed in each circuit board area of the large circuit board and the lid 2 are stably electrically connected. Will be.

Next, division processing is performed for each circuit board area.

In this step, a large circuit board having a plurality of circuit board regions to which the lid 2 has already been joined is subjected to a division process for each circuit board region. In the dividing process, for example, a dividing groove is formed in a large circuit board in advance, and the dividing process may be performed along the dividing groove. Alternatively, the dividing process may be performed by cutting and separating using a cutting jig. Good.

Thereafter, an external visual inspection and a characteristic inspection are performed as required.

As described above, since the lid 2 is placed on and joined to the surface of the circuit board 1, the large circuit board can be joined to the surface before the circuit board is divided. If the division processing is performed for each area, a high-frequency circuit component can be obtained immediately.

That is, in the conventional structure, since the lid is bonded to the end face of the circuit board, in order to improve the mass productivity of the circuit board, it is easy to use a large circuit board before the circuit board is divided. The structure was such that the lid could not be attached.

In the above-described structure, as shown in FIG. 1 and FIG.
In addition to forming terminal electrodes on the end surface of the circuit board, for example,
A terminal electrode is formed on the end surface of the circuit board, and a concave portion is formed at a position that is greatly recessed from the position of the side surface of the lid, and the terminal electrode is formed in the concave portion, or penetrates the thickness direction of the circuit board. Various modifications are possible, such as providing a wiring conductor and forming a terminal electrode on the bottom surface of the circuit board so as to connect to the wiring conductor.

[0045]

As described above, according to the present invention, since the lid is joined to the surface of the circuit board, when the circuit board is formed from a large circuit board, the lid is placed on the large circuit board. Since high-frequency circuit components can be integrally formed by joining, it is very excellent in mass productivity.

The connection between the circuit board and the lid is made by connecting a wiring conductor (connection pad) having a ground potential extending to the outer periphery of the surface of the circuit board with a joining piece projecting inward at a part of the side surface of the lid. Is performed with a conductive adhesive, and the conductive adhesive is supplied and hardened on the outer surface side of the joining piece, so that the conductive adhesive hardly wraps around the inside of the lid, and the spread conductive adhesive is used. Since a short circuit with a predetermined wiring conductor and the generation of a stray capacitance component are unlikely to occur, a connection structure in which the characteristics of the high-frequency circuit component can be stably maintained.

In addition, since the joining with the conductive adhesive is performed using the outer surface of the joining piece, the joining state can be visually confirmed.

Further, the notch formed in the joint piece can suppress the conductive adhesive from spreading to the outer surface of the joint piece, and the notch can determine the excess amount of the conductive adhesive, so that the notch can be used. This makes it possible to observe the inside of the joined portion through the part, and to provide a high-frequency circuit component having a very reliable joining structure, and a very simple joining structure for inspecting the joining condition.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a high-frequency circuit component according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a process flowchart illustrating a method for manufacturing a high-frequency circuit component according to the present invention.

[Description of Signs] 1... Circuit board 10... Dielectric substrate 11... Wiring conductor at ground potential 12... Wiring conductor 2. 3 ... joining piece 31 ... cutout part 4 ... conductive adhesive

Claims (1)

[Claims] 1. A ceramic or organic resin material,
A high-frequency circuit component in which a substantially rectangular parallelepiped metal lid is joined to a circuit board having a wiring conductor and various electronic components formed on a surface thereof so as to cover the wiring conductor and the electronic component. A ground potential wiring conductor is formed on the outer periphery of the surface, and the lid is formed with a joining piece that protrudes inward on the side surface and has a cutout portion that narrows the width at the center thereof. The high-frequency circuit component is joined to the circuit board by a conductive adhesive disposed in a recess formed between a joint piece of the lid and a ground potential wiring conductor of the circuit board.