JPH09275269A - Method of mounting electronic elements on circuit board, electronic elements and circuit board used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount electronic elements on a circuit board, without using solder. SOLUTION: An electronic element 10A has outwards extended connecting terminals 11A. An interconnection pattern 12 formed on a circuit board 13, lands of which have finely roughed faces. The external connecting terminals 11A are positioned so as to lie on the roughed lands of the pattern 12 and then pressed to the board 13 to thereby electrically connect the terminals 11a to the interconnection pattern 12 and fix the electronic element 10A to the circuit board 13.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to electronic components (including electrical components).
The present invention relates to a method for mounting a semiconductor device on a circuit board, and electronic components and circuit boards used for the method.

[0002]

2. Description of the Related Art Conventionally, in order to mount an electronic component on a circuit board, a method of connecting a wiring pattern on the substrate and an external connection terminal of the electronic component by solder has been generally used.

Solder is an alloy of lead and tin. The composition of the solder that is mainly used in electric circuits is approximately 63% lead and 37% tin. Circuit boards on which electronic elements and electronic components are mounted using solder are found everywhere inside electrical products for both industrial and home use.

Lead (Pb) contained in solder is a harmful substance and has a property of being easily dissolved in acid. For this reason, in recent years, it has been feared that the solder contained in discarded electrical appliances will start to melt due to the influence of acid rain, and lead contained in the solder will flow out. Lead spills can cause serious environmental pollution and, as a result, adversely affect the human body.

In the mounting process using the solder,
At the time of mounting, not only the connecting part of the electronic component and the circuit board,
All other parts are also exposed to high temperatures. Therefore, the electronic component or the circuit board may be thermally damaged.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a method for mounting an electronic component on a circuit board without using solder.

The present invention also provides an electronic component that can be mounted on a circuit board without using solder, and a circuit board that can mount the electronic component.

In the method of mounting an electronic component according to the present invention, fine unevenness is formed in a portion of the wiring pattern formed on the circuit board at which the external connection terminal of the electronic component is to be connected, and the connection surface of the external connection terminal is The electronic component is arranged so as to oppose the unevenness on the wiring pattern, and the unevenness is bitten into the connection surface of the external connection terminal by pressing the external connection terminal toward the circuit board, and the external connection is performed. The terminals are electrically connected to the wiring patterns, and the electronic parts are fixed to the circuit board.

According to the method of mounting an electronic component of the present invention, fine unevenness is formed on the connection surface of the external connection terminal of the electronic component,
The electronic component is arranged such that the unevenness of the connection surface of the external connection terminal opposes a portion of the wiring pattern formed on the circuit board to which the external connection terminal is to be connected, and the external connection terminal is connected to the circuit board. By pressing in the direction of, the unevenness is bitten into the wiring pattern, the external connection terminal and the wiring pattern are electrically connected, and the electronic component is fixed to the circuit board.

Fine irregularities may be formed on both the portion of the wiring pattern to which the external connection terminal of the electronic component is to be connected and the connection surface of the external connection terminal. A bump may be provided on the wiring pattern or the external connection terminal, and unevenness may be formed on the surface of the bump.

In the circuit board according to the present invention, fine irregularities are formed in the wiring pattern formed on the circuit board at locations to which the external connection terminals of the electronic component are to be connected.
Bumps made of a material having a conductivity different from that of the wiring pattern may be formed on the wiring pattern on the circuit board, and fine bumps may be formed on the bumps.

The electronic component according to the present invention has an external connection terminal, and fine irregularities are formed on the connection surface of the external connection terminal.

The electronic parts include resistors, capacitors, coils, various semiconductor elements, sensors, IC circuits (including LSI), and all other electrical and electronic elements and parts mounted on a circuit board.

According to the present invention, the electrical connection between the external connection terminal of the electronic component and the wiring pattern of the circuit board and the fixing of the electronic component to the circuit board press the external connection terminal or the electronic component toward the circuit board. To be achieved. Therefore, electronic components can be mounted without using solder as in the past. Since no solder containing lead is used, there is no risk of environmental pollution caused by discarded electrical equipment. Since the mounting is performed only by pressure, the electronic component or the circuit board is not damaged by heat. Also, the fine irregularities on the wiring pattern bite into the external connection terminal, or the fine irregularities on the external connection terminal bite into the wiring pattern, and the contact area between the external connection terminal and the wiring pattern increases, so the ohmic resistance is small, And the mounting strength is strong.

It is more preferable to apply an ultrasonic vibration to the connecting portion between the external connection terminal and the wiring pattern while pressing the external connection terminal or the electronic component toward the circuit board. Stronger mounting is achieved than mounting by pressing only.

In the method of mounting an electronic component according to the present invention, a recess is formed in a wiring pattern formed on a circuit board at a position to which an external connection terminal of the electronic component is to be connected, and a metal film is formed on the inner surface of the recess and its periphery. A part of the external connection terminal is formed by arranging the electronic component so that the connection surface of the external connection terminal faces the recess and pressing the external connection terminal toward the circuit board. The electronic component is fitted in the recess to electrically connect the external connection terminal and the wiring pattern, and the electronic component is fixed to the circuit board.

In the circuit board according to the present invention, a recess is formed in a portion of the wiring pattern formed on the circuit board to connect the external connection terminal of the electronic component, and the recess is covered with a metal film.

According to the present invention, the electronic component is fixed to the circuit board by pressing the external connection terminal and fitting a part of the external connection terminal into the recess on the circuit board. Therefore, electronic parts can be mounted without using solder. The problem of environmental pollution can be solved, and damage to the circuit board due to heat can be prevented.

The recess on the circuit board may be directly formed on the circuit board. It is also possible to previously form a surface layer such as a solder resist on the circuit board and etch the surface layer to form the recess.
It is also possible to form the recess by using two circuit boards, making a hole in one circuit board, and joining the one circuit board to the other circuit board.

In the method of mounting an electronic component according to the present invention, a piercing tool having a sharp tip is attached to the electronic component, and the external connection terminal of the electronic component connects the electronic component of the wiring pattern formed on the circuit board. The electronic component is arranged so as to oppose to the place where it should be, and the external connection terminal and the wiring pattern are electrically connected by piercing the circuit board with the piercing tool, and the electronic component is laid on the circuit board. It is something that is fixed.

The electronic component according to the present invention has a sharp tip and is provided with a piercing tool attached to the electronic component so as to project from both side surfaces of the electronic component.

In one embodiment of the circuit board according to the present invention, the portion of the circuit board where the piercing tool is to be pierced is made of a soft material. For example, a soft material is embedded in the place where the piercing device is pierced.

According to the present invention, the piercing tool attached to the electronic component pierces the circuit board to fix the electronic component to the circuit board. Therefore, the electronic component can be mounted on the circuit board without using any solder. A burr may be formed on the tip of the piercing device.
Since electronic parts can be prevented from falling off the circuit board, reliability of mounting is improved.

According to the method of mounting an electronic component of the present invention, a conductive protrusion is provided on the connection surface of the external connection terminal of the electronic component,
A hole is formed in the wiring pattern formed on the circuit board at a position to which the external connection terminal is to be connected, and a hole into which the protrusion is fitted is formed. An electronic component is arranged so that the protrusion and the hole face each other. By pressing the electronic component in the direction of the circuit board, the projection is fitted into the hole, the electronic component is fixed to the circuit board, and the external connection terminal and the wiring pattern are electrically connected. Is.

In the electronic component according to the present invention, the external connection terminal is provided with a protrusion that is fitted into a hole formed in a portion of the wiring pattern formed on the circuit board to connect the external connection terminal of the electronic component. Is.

In the circuit board according to the present invention, holes are formed in the wiring pattern formed on the circuit board at positions to which the external connection terminals of the electronic component are to be connected.

According to this invention, the electronic component is fixed to the circuit board by fitting the protrusion formed on the connection surface of the external connection terminal of the electronic component into the hole formed on the circuit board. Therefore, electronic components can be mounted without using solder.

According to the method of mounting an electronic component of the present invention, a conductive pin is provided between the external connection terminal of the electronic component and a portion of the wiring pattern formed on the circuit board where the external connection terminal of the electronic component is to be mounted. Is inserted, whereby the electronic component is fixed to the circuit board, and the external connection terminal and the wiring pattern are electrically connected.

By inserting the pin between the external connection terminal of the electronic component and the portion on the wiring pattern where the external connection terminal is to be mounted, the electronic component can be fixed to the circuit board. Therefore, electronic parts can be mounted without using solder. The external connection terminal and the wiring pattern are electrically connected.

There are many types of circuit boards.
The first is that a wiring pattern is formed on one surface of the circuit board,
The electronic component is mounted on the surface on which the wiring pattern is formed. The other is that a wiring pattern is formed on one surface of the circuit board and electronic components are mounted on the other surface. In this case, a through hole and a land portion connected to the wiring pattern through the through hole are formed on the surface on which the electronic component is mounted. The peripheries and lands of these through holes correspond to (where) the external connection terminals of the electronic component of the wiring pattern formed on the circuit board are connected. The third is a wiring pattern formed on both surfaces of the circuit board. The present invention can be applied to any type of circuit board.

[0031]

【Example】

First Embodiment FIG. 1 shows how electronic components are mounted on a circuit board. 2 is a sectional view taken along line II-II of FIG.
(A) shows the state before mounting the electronic parts on the circuit board,
(B) shows the respective states after mounting. FIG.
In the figure, the illustration of the internal structure of the electronic component is omitted.
This also applies to the other figures.

The electronic component 10A includes a plurality of external connection terminals 11A. The external connection terminals 11A project outward from both side surfaces of the housing that forms the outer frame of the electronic component 10A, and the tips (connection surfaces) are formed so as to be parallel to the surface of the circuit board 13 on which the electronic component 10A is mounted. Has been done. The external connection terminal 11A is made of copper alloy, gold, aluminum or the like. The wiring pattern 12 is formed on the mounting surface of the circuit board 13. The circuit board 13 is made of glass epoxy, glass polyester, or the like, and the wiring pattern 12 is made of copper or the like.

Fine concavities and convexities (preferably pointed in a sawtooth shape) are formed at locations (hereinafter, referred to as lands 12a) on the wiring pattern 12 where the external connection terminals 11A are connected.

The electronic component 10A is positioned so that the connection surface of the external connection terminal 11A and the land 12a are vertically overlapped, and then pressure is applied to the tip of the external connection terminal 11A in the direction of the circuit board 13. As the material of the land 12a, a metal member harder than the material of the external connection terminal 11A is used. The unevenness of the land 12a caused by the pressure is applied to the external connection terminal 11A.
Bite into the connection surface of. As a result, the external connection terminal 11A and the wiring pattern 12 are electrically connected and the electronic component 10
A is fixed to the circuit board 13. The unevenness of the land 12a may be directly formed on the wiring pattern 12.
The unevenness may be formed in advance on a metal member different from 12, and the metal member may be provided in a state of being connected to the wiring pattern 12.

Since the connecting portion between the external connection terminal 11A and the land 12a both has an uneven surface, the contact area is large. This improves the bonding strength (mounting strength) and the conductivity between the external connection terminal 11A and the wiring pattern 12.

Preferably, ultrasonic vibration is applied to the connecting portion between the external connection terminal 11A and the land 12a at the same time as pressure is applied to the tip portion of the external connection terminal 11A. By applying ultrasonic vibration, a stronger connection can be achieved compared to the case where only pressure is applied. This also applies to the examples described later.

FIG. 3 shows another embodiment, which shows a state before mounting electronic components on a circuit board.

The lower surface (connection surface) of the tip portion 11a of the external connection terminal 11A of the electronic component 10A is formed with fine irregularities (preferably pointed in a sawtooth shape).

External connection terminal 11A on which fine irregularities are formed
The electronic component 10A is positioned so that the connection surface of the tip portion 11a and the land 12a are vertically overlapped, and then pressure is applied to the tip portion 11a of the external connection terminal 11A in the direction of the circuit board 13. Land 12 is used as the material for the external connection terminal 11A.
A metal member harder than the material of a is used. As a result of pressure, the unevenness of the connection surface of the tip portion 11a of the external connection terminal 11A cuts into the land 12a. This allows the external connection terminal 11
A and the wiring pattern 12 are electrically connected, and the electronic component 10A is fixed to the circuit board 13.

FIG. 4 shows still another embodiment, showing a state before mounting electronic components on a circuit board.

Fine irregularities are formed on both the lower surface (connection surface) of the tip portion 11a of the external connection terminal 11A of the electronic component 10A and the land 12a of the wiring pattern 12 on the circuit board 13.

External connection terminal 11A on which fine irregularities are formed
The electronic component 10A is positioned so that the convex portion (or concave portion) of the connection surface of the tip portion 11a of the tip and the concave portion (or convex portion) of the land 12a, which also has fine irregularities, vertically overlap, and then the circuit External connection terminal 11A in the direction of board 13
Pressure is applied to the tip portion 11a of the. External connection terminal 11A
The land and the land 12a may have the same hardness, or one of them may be softer than the other. As a result of pressure, the unevenness of the connection surface of the tip portion 11a of the external connection terminal 11A and the unevenness of the land 12a bite into each other. Alternatively, one unevenness cuts into the other unevenness. As a result, the external connection terminal 11A and the wiring pattern 12 are electrically connected, and the electronic component 10A is fixed to the circuit board 13.

FIG. 5 shows still another example of mounting electronic components on a circuit board. FIG. 5A shows a state before mounting,
(B) shows the respective states after mounting.

On the lower surface of the electronic component 10B, a plurality of external connection terminals 11B are provided so as to be exposed. External connection terminal 11
Bumps 14 (hereinafter referred to as component-side bumps) are formed on the surface of B. External connection terminal 11B on wiring pattern 12
The part side bump 14 is connected to the (part side bump 14)
Bumps 15 (hereinafter referred to as substrate-side bumps) made of a harder material are formed. The board-side bumps 15 are electrically connected to the wiring pattern 12, and fine unevenness is formed on the mounting surface thereof. Gold, copper, etc. are used for the material of the bump.

The electronic component 10B is positioned so that the component-side bump 14 and the substrate-side bump 15 are vertically overlapped with each other, and then pressure is applied to the electronic component 10B in the direction of the circuit board 13. Due to this pressurization, the unevenness of the substrate-side bumps 15 bites into the component-side bumps 14. As a result, the external connection terminal 11B and the wiring pattern 12 are connected to the component-side bump 14 and the substrate-side bump
Electronically connected via 15 and electronic component 10B is the circuit board
Fixed to 13.

In this embodiment, fine irregularities are formed on the surface of the board-side bumps 15 provided on the wiring pattern 12, but as shown in FIG. 3, the bumps 15 are formed on the external connection terminal side (component-side bump 14). Fine irregularities may be formed, or fine irregularities may be formed on both the substrate-side bumps 15 and the component-side bumps 14 as shown in FIG.

FIGS. 6A to 6C show an example of a process of forming fine irregularities on a wiring pattern (land).

A wiring pattern 12 is formed on the circuit board 13. A press die 16 having fine irregularities is prepared (FIG. 6 (A)). The press die 16 is made of a material harder than the material (copper or the like) used for the wiring pattern 12.

A wiring pattern is formed on the fine uneven surface of the press die 16.
The 12 ruggednesses are applied to the surface of the land 12a to be formed and pressed (FIG. 6 (B)). After that, the press die 16 is separated from the wiring pattern 12. As a result, unevenness is formed on the land 12a (FIG. 6C).

The formation of fine irregularities on the land 12a is not limited to the press forming method using the above-mentioned press die, but a rough surface is formed by mechanical grinding (roughly scraping) or corrosion by a chemical agent (for example, strong acid). The method of doing can also be used. The unevenness of the connection surface at the tip of the external connection terminal and the unevenness of the bump can be similarly formed.

Second Embodiment FIG. 7 shows a second embodiment in which electronic components are mounted on a circuit board. (A) shows a state before mounting, and (B) shows a state after mounting. ing.

A surface layer 18 is formed on the entire surface of the circuit board 13, and a wiring pattern 12 is formed on the surface layer 18. The surface layer 18 is formed of a solder resist, a substrate, etc., as described later.

A recess 19 is formed in the surface layer 18 at a portion corresponding to the land of the wiring pattern 12. This recess
19 is formed up to the surface of the substrate 13. A metal film 17 is formed so as to cover the recess 19. The metal film 17 is electrically connected to the wiring pattern 12.

The electronic component 10A is positioned so that the tip portion 11a of the external connection terminal 11A of the electronic component 10A is located on the recess 19, and then the external connection terminal 11A is oriented toward the circuit board 13.
Pressure is applied to the tip portion 11a of A. By pressing, the tip portion 11a of the external connection terminal 11A fits into the recess 19 of the circuit board 13. As a result, the external connection terminal 11A and the wiring pattern 12 are electrically connected via the metal film 17, and the electronic component 10 is fixed to the circuit board 13.

It is desirable that the recess 19 of the circuit board 13 be formed slightly smaller than the tip portion 11a of the external connection terminal 11A. As a result, the tip portion 11 of the external connection terminal 11A
Since the a and the metal film 17 can contact from the bottom surface of the recess 19 to the side surface and the periphery thereof, the mounting strength of the electronic component 10A and the conductivity between the external connection terminal 11A and the wiring pattern 12 are improved. To do.

The recesses and the metal film can be formed on the circuit board by various methods. Examples thereof are shown in FIGS. 8 to 10.

FIG. 8 shows a step of forming a surface layer using a solder resist.

A solder resist 18A serving as a surface layer 18 is formed on the entire surface of the circuit board 13. This solder resist
A wiring pattern 12 is formed on 18A.

A part of the wiring pattern 12 and the solder resist 18A is removed by etching at a portion corresponding to a land to which the external connection terminal of the electronic component is to be connected to form a recess.
Form 19.

A metal foil 17A slightly larger than this is placed on the recess 19 formed on the substrate 13 (FIG. 8A), and the punch 29 drives the metal foil 17A into the recess. This gives
The inner surface of the recess 19 and the peripheral edge thereof are covered with the metal foil 17A (FIG. 8B).

FIG. 9 shows a step of forming a surface layer using a substrate.

A circuit board 18B serving as the surface layer 18 is prepared. A wiring pattern 12 is formed on the surface of the circuit board 18B, and through holes 20 are formed on the wiring pattern 12 at locations corresponding to lands to which external connection terminals of electronic components are to be connected. The inner peripheral surface and the periphery of the through hole 20 are plated with copper, gold or the like. This plating (hereinafter referred to as through hole plating) 21 and the wiring pattern
12 and 12 are electrically connected (FIG. 9 (A)).

Such a circuit board 18B is attached to a board 13 having a flat surface by the surface on which the wiring pattern 12 is not formed, by an adhesive or the like (FIG. 9B).

FIG. 10 shows a step of forming a metal film by electroless plating.

A solder resist 18A serving as the surface layer 18 is formed on the entire surface of the circuit board 13. This solder resist
A wiring pattern 12 is formed on 18A.

A part of the wiring pattern 12 and the solder resist 18A is removed by etching at a portion corresponding to a land to which the external connection terminal of the electronic component is to be connected to form a recess.
Form 19.

The catalyst nucleus-containing adhesive 22 is sprayed on the inner surface of the recess 19 and its surroundings by using a spray or the like to attach the catalyst nucleus to the place where the metal film is to be formed (FIG. 10A). When the circuit board 13 with the catalyst nucleus attached is immersed in the electroless plating solution,
The metal ions in the electroless plating solution chemically react with the catalyst nuclei, and the metal ions are deposited in the recesses 19 to which the catalyst nuclei are attached and in the periphery thereof to form the plating 17B (FIG. 10).
(B)). With this method, it is possible to form the plating 17B of a metal or alloy such as copper, nickel or gold.

A surface layer 18 (solder resist) is formed on the surface of the substrate 13.
It is also possible to form the recess 19 directly on the surface of the substrate 13 without providing the substrate 18A or the substrate 18B, and to form the metal film 17 on the inner surface of the recess 19 and the peripheral edge thereof, and use this as the land of the wiring pattern. .

Third Embodiment FIG. 11 shows a third embodiment in which electronic components are mounted on a circuit board. (A) shows a state before mounting and (B) shows a state after mounting. ing.

The external connection terminals 11C are formed on both end portions of the electronic component 10C so as to cover the entire outer periphery thereof. Further, the electronic component 10C is provided with a piercing metal fitting 23 at its central portion (a position where it does not make electrical contact with the external connection terminal 11C). The piercing metal fitting 23 is closely fixed to the upper surface and the side surface of the electronic component 10C. The tip portion of the piercing metal fitting 23 projects downward from both side surfaces of the electronic component 10C, and its tip end is sharply pointed. The piercing metal fitting 23 is made of iron, steel, or another material. The piercing metal fitting 23 may be made of a hard synthetic resin instead of a metal fitting.

The electronic component 10C is positioned so that the external connection terminals 11C and the lands 12a of the wiring pattern 12 formed on the substrate 13 are vertically overlapped, and then pressure is applied to the electronic component 10C in the direction of the circuit board 13. To be The circuit board 13 is filled with the silicone resin 24 at the portion where the piercing metal fitting 23 bites. The piercing metal fitting 23 is pierced into the silicone resin 24 by pressurization. The length of the piercing metal fitting 23 is made so as not to protrude from the back surface of the circuit board 13 when the piercing metal fitting 23 is completely embedded in the circuit board 13.

Since the piercing metal fitting 23 pierces the silicon resin 24, the electronic component 10C and the circuit board 13 are fixed and the external connection terminal 11C is connected to the land 12a, so that the external connection terminal 11C and the wiring pattern 12 are separated from each other. It is electrically connected.

A method of attaching the piercing metal fitting to the electronic component will be described with reference to FIG.

A piercing metal fitting 23 extending in a straight line is prepared. When the piercing metal fitting 23 is attached to the electronic component 10C, the parts of the piercing metal fitting 23 protruding from the side surface of the electronic component 10C are equal on both side surfaces.
Align the center of 23 with the center of electronic component 10C.

Using a mold 25 having an upper surface of the electronic component 10C and three surfaces along the both side surfaces, and the distance between the two surfaces along the both side surfaces of the electronic component 10C is set to be substantially equal to the width of the electronic component 10C. ， Press the piercing metal fitting 23 along the electronic component 10C. The mold 25 is made of a material harder than the material of the piercing metal fitting 23.

After pressing, when the mold 25 is released, the piercing metal fitting 23 is tightly fitted on the upper surface and both side surfaces of the electronic component 10C.

By using the force applied when attaching the piercing metal fitting 23 to the electronic component 10C, it is possible to attach the piercing metal fitting 23 to the electronic component 10C and mount the electronic component 10C on the circuit board 13 at the same time. Is.

As shown in FIG. 13, a barb 23a may be formed at the tip of the piercing metal fitting 23. The barbs 23a of the piercing metal fitting 23 once pierced into the silicone resin loaded in the circuit board 13 are caught by the silicone resin. This makes it possible to prevent the electronic component from falling off the circuit board.

FIG. 14 shows another example of mounting an electronic component to which a piercing metal fitting is attached. The same members as those shown in FIG. 11 are designated by the same reference numerals to avoid redundant description.

By mounting a plurality of piercing metal fittings 23 on the electronic component 10C and piercing the plurality of piercing metal fittings on the silicone resin loaded in the circuit board 13, the mounting strength of the electronic component 10C can be further increased.

Fourth Embodiment FIGS. 15A and 15B show a fourth embodiment in which electronic parts are mounted on a circuit board. FIG. 15A shows a state before mounting, and FIG. 15B shows a state after mounting. ing.

A plurality of external connection terminals 11B are provided on the lower surface of the electronic component 10B so as to be exposed. External connection terminal 11
A gold bump 26 is provided at the central portion of the lower surface of B so as to project downward. The gold bump 26 has a thin tip and is formed so that it gradually becomes thicker toward the location fixed to the external connection terminal 11B. The external connection terminal 11B and the gold bump 26 are electrically connected.

Through holes 20 are formed in the circuit board 13, and through hole plating 21 covers the inner peripheral surface and the periphery thereof. The through hole plating 21 is electrically connected to the wiring pattern 12. The tip of the gold bump 26 is formed slightly smaller than the diameter of the through hole 20.
It is preferable to form the root part of the thicker than the diameter of the through hole 20. By utilizing the fact that the tip portion of the gold bump 26 enters the through hole 20, the electronic component 10B can be positioned relatively easily.

Pressure is applied to the aligned electronic component 10B in the direction of the circuit board 13 from above. A metal member softer than the through-hole plating 21 is used for the gold bump 26. By pressing, a portion of the gold bump 26 that is thicker than the diameter of the through hole 20 bites into the through hole 20. As a result, the electronic component 10B and the circuit board 13 are fixed, and the external connection terminal 11B and the wiring pattern 12 are electrically connected.

16A and 16B show still another example of mounting electronic components on a circuit board. FIG. 16A shows a state before mounting and FIG. 16B shows a state after mounting.

The electronic component 10B has a plurality of external connection terminals 11B exposed on its lower surface. External connection terminal 11
The component side bumps 14 are formed on the surface of B.

A surface layer 18 is formed on the entire surface of the circuit board 13, and a wiring pattern 12 is formed on the surface layer 18. The surface layer 18 is formed of a solder resist, a substrate or the like.

A concave portion 19 is formed in the surface layer 18 at a portion corresponding to the land of the wiring pattern 12. The recess 19 is formed up to the surface of the substrate 13. A metal film 17 is formed so as to cover the recess 19. The metal film 17 is electrically connected to the wiring pattern 12. The recess 19 is formed smaller than the lower surface of the external connection terminal 11B of the electronic component 10B (connection surface of the component-side bump 14).

A conductive press-fitting pin 27 is inserted and fixed in the recess 19 so as to be in close contact with the peripheral surface thereof. The press-fitting pin 27 may be fixed by tightly fitting it on the inner surface of the recess 19, or may be fixed via a conductive adhesive or the like. As the material of the press-fitting pin 27, a metal member harder than the material of the component side bump 14 is used.

The electronic component 10B is positioned so that the press-fitting pin 27 is located at the center of the external connection terminal 11B (component-side bump 14), and then pressure is applied to the electronic component 10B in the direction of the circuit board 13. The press-fitting causes the press-fitting pin 27 to bite into the component-side bump 14. As a result, the external connection terminal 11B and the wiring pattern 12 are electrically connected via the terminal side bump 14, the metal film 17 and the press-fitting pin 27, and the electronic component 10B is fixed to the circuit board 13.

[0091]

[Brief description of drawings]

FIG. 1 shows a first embodiment and is a perspective view showing an entire electronic component mounted on a circuit board.

2A and 2B show a first embodiment, FIG. 2A is a sectional view showing a part of an electronic component and a circuit board before mounting, and FIG. 2B is a part of a circuit board after mounting the electronic component. FIG.

FIG. 3 is a cross-sectional view showing a modified example of the first embodiment and showing a part of an electronic component and a circuit board before mounting.

FIG. 4 is a cross-sectional view showing a modification of the first embodiment and showing a part of an electronic component and a circuit board before mounting.

FIG. 5 shows a modification of the first embodiment, in which (A) is a cross-sectional view showing a part of an electronic component and a circuit board before mounting, (B).
FIG. 4 is a cross-sectional view showing a part of an electronic component and a circuit board after mounting.

6 (A), (B), and (C) show a process of forming fine unevenness on a land on a wiring pattern.

7A and 7B show a second embodiment, FIG. 7A is a cross-sectional view showing a part of an electronic component and a circuit board before mounting, and FIG. 7B is a part of a circuit board after mounting the electronic component. FIG.

FIG. 8 shows a step of forming a recess and a step of forming a metal film on a circuit board.

FIG. 9 shows a step of forming a recess and a step of forming a metal film on a circuit board.

FIG. 10 shows a step of forming a recess and a step of forming a metal film on a circuit board.

FIG. 11 shows a third embodiment, (A) is a front view (partially sectional view) showing a part of an electronic component and a circuit board having a fitting before mounting, and (B) is after mounting. 3 is a front view (partially sectional view) showing a part of the electronic component and the circuit board of FIG.

12 (A) and 12 (B) are perspective views showing a process of attaching a fitting to an electronic component.

FIG. 13 is a front view showing another example of the shape of the tip of the insertion fitting.

FIG. 14 is a front view showing a state in which an electronic component having a plurality of insertion fittings is mounted on a circuit board.

15A and 15B show a fourth embodiment, FIG. 15A is a sectional view showing a part of an electronic component and a circuit board before mounting, and FIG. 15B is a part of a circuit board after mounting the electronic component. FIG.

FIG. 16 shows a modification of the fourth embodiment, in which (A) is a cross-sectional view showing a part of an electronic component and a circuit board before mounting,
FIG. 3B is a sectional view showing a part of the electronic component and the circuit board after mounting.

[Explanation of symbols]

 10A, 10B, 10C Electronic component 11A, 11B, 11C External connection terminal 12 Wiring pattern 12a Land 13 Circuit board 14 Component side bump 15 Board side bump 16 Press type 17 Metal film 18 Surface layer 19 Recess 20 Through hole 21 Through hole plating 22 Adhesive with catalyst core 23 Stab metal 24 Silicon resin 26 Gold bump 27 Press-fit pin 29 Punch

Front Page Continuation (72) Inventor Takashi Totani 10 Ouron Co., Ltd., Hanazono-cho, Ukyo-ku, Kyoto City, Kyoto Prefecture Omron Co., Ltd. Within

Claims (21)

[Claims] 1. A fine concavo-convex pattern is formed at a portion of an electronic component of a wiring pattern formed on a circuit board to which an external connection terminal is to be connected, and a connection surface of the external connection terminal opposes the concavo-convex pattern on the wiring pattern. The electronic parts are arranged so that the external connection terminals are pressed in the direction of the circuit board so that the irregularities are bitten into the connection surface of the external connection terminals, and the external connection terminals and the wiring pattern are electrically connected. Electrically, and fixing the electronic component to the circuit board,
Electronic component mounting method. 2. The mounting method for an electronic component according to claim 1, wherein a bump is provided on the wiring pattern, and the unevenness is formed on the bump. 3. A fine concavo-convex pattern is formed on the connection surface of the external connection terminal of the electronic component, and the concavo-convex pattern of the connection surface of the external connection terminal is formed.
By disposing the electronic component so as to face a portion of the wiring pattern formed on the circuit board where the external connection terminal is to be connected, and pressing the external connection terminal in the direction of the circuit board Biting into the wiring pattern, electrically connecting the external connection terminal to the wiring pattern, and fixing the electronic component to the circuit board,
Electronic component mounting method. 4. A bump is provided on the connection surface of the external connection terminal,
The method of mounting an electronic component according to claim 3, wherein the unevenness is formed on the bump. 5. A fine first portion is provided at a portion to be connected to an external connection terminal of an electronic component of a wiring pattern formed on a circuit board.
Is formed on the connection surface of the external connection terminal of the electronic component so that the projections and depressions on the wiring pattern and the connection surface of the external connection terminal face each other. By arranging an electronic component and pressing the external connection terminal toward the circuit board, the unevenness of the connection surface of the external connection terminal and the unevenness on the wiring pattern bite into each other, and the external connection terminal and the wiring A method for mounting an electronic component, comprising electrically connecting a pattern and fixing the electronic component to the circuit board. 6. A bump is provided on the wiring pattern, the first unevenness is formed on the bump, a bump is provided on a connection surface of the external connection terminal, and the second unevenness is formed on the bump. The electronic component mounting method according to claim 5. 7. A concave portion is formed at a portion to be connected to an external connection terminal of an electronic component of a wiring pattern formed on a circuit board, and a metal film is formed on an inner surface of the concave portion and its periphery,
The electronic component is arranged such that the connection surface of the external connection terminal faces the recess, and the external connection terminal is pressed in the direction of the circuit board so that a part of the external connection terminal is fitted into the recess. A method for mounting an electronic component, wherein the external connection terminal and the wiring pattern are electrically connected and the electronic component is fixed to the circuit board. 8. A piercing tool having a sharp tip is attached to an electronic component, and the external connection terminal of the electronic component is opposed to a portion of a wiring pattern formed on a circuit board to which the electronic component is to be connected. A method of mounting an electronic component, wherein an electronic component is arranged, the piercing tool is pierced into the circuit board to electrically connect the external connection terminal to the wiring pattern, and the electronic component is fixed to the circuit board. 9. The method of mounting an electronic component according to claim 8, wherein a material of a portion of the circuit board where the piercing tool is to be pierced is soft. 10. A conductive projection is provided on a connection surface of an external connection terminal of an electronic component, and a hole for fitting the projection is provided in a portion of a wiring pattern formed on a circuit board to which the external connection terminal is to be connected. The electronic component is formed so that the protrusion and the hole are opposed to each other, and the protrusion is fitted into the hole by pressing the electronic component toward the circuit board. A method for mounting an electronic component, which is fixed to a substrate and electrically connects the external connection terminal and the wiring pattern. 11. A conductive pin is inserted between an external connection terminal of an electronic component and a portion of a wiring pattern formed on a circuit board where the external connection terminal of the electronic component is to be mounted. A method for mounting an electronic component, wherein a component is fixed to the circuit board and the external connection terminal and the wiring pattern are electrically connected. 12. The ultrasonic vibration is applied to a portion connecting the external connection terminal to the wiring pattern while pressing the external connection terminal or the electronic component toward the circuit board. A method for mounting an electronic component according to item 1. 13. A circuit board in which fine irregularities are formed at locations where external connection terminals of an electronic component of a wiring pattern formed on the circuit board are to be connected. 14. The circuit board according to claim 13, wherein bumps made of a material having a conductivity different from that of the material of the wiring pattern are formed on the wiring pattern, and the unevenness is formed on the bumps. 15. An electronic component having an external connection terminal, wherein fine irregularities are formed on a connection surface of the external connection terminal. 16. A circuit board in which a recess is formed in a portion of the wiring pattern formed on the circuit board to connect an external connection terminal of an electronic component, and the recess is covered with a metal film. 17. An electronic component, which has a sharp tip and is equipped with a piercing tool attached to the electronic component so as to project from both side surfaces of the electronic component. 18. The electronic component according to claim 17, wherein a burr is formed on a tip of the piercing tool. 19. A circuit board in which a soft material is embedded in a portion where a stab provided on an electronic component to be mounted is stabbed. 20. An electronic component in which a conductive protrusion is fitted into a hole formed in a portion of an electronic component of a wiring pattern formed on a circuit board to which the external connection terminal is connected. 21. A circuit board in which a hole is formed at a position to which an external connection terminal of an electronic component of a wiring pattern formed on the circuit board is to be connected.