JPH09283686A - Electronic component, manufacture of electronic component and mounting method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain stable mounting quality even in high density mounting by providing a connecting means consisting of a material containing a metallic element forming a soft soldering material or soft solder and a solid soluble body for connecting a plurality of terminals mutually. SOLUTION: An electronic component body 7 is comprised of a material containing a metallic element forming a soft soldering material or soft solder and a solid soluble body. End parts of a plurality of terminals 8 of the electronic component body 7 are connected by a strip solder sheet 9 as a connecting means. The soft solder sheet 9 is thereby stuck in the terminal 8 and is readily compressed. The solder sheet 9 dissolves and the part between terminals 8 is separated by surface tension during the dissolving and concentrates on the part of the terminal 8. The electronic component body 7 is subjected to surface mounting by solder 9a. Since the terminals are connected mechanically by the strip solder sheet 9 in this way, mechanical strength of the terminal 8 increases and stable mounting becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component, a method of manufacturing the electronic component, and a mounting method thereof.

[0002]

2. Description of the Related Art Surface mounting technology is widely used as a method for mounting electronic components on a circuit board. In this technique, as shown in FIG. 4, cream solder 3 is arranged on a land 2 provided on a circuit board 1 by using a printing machine or the like, and terminals 5 of an electronic component 4 are mounted thereon. This is a technique in which the cream solder 3 is melted through a reflow furnace and the terminals 5 are solder-bonded onto the lands 2.

The land 2 may be plated with solder without printing the cream solder 3. As the solder material, various soft brazing materials other than general eutectic solder are used depending on the application.

[0004]

With the recent miniaturization of electronic equipment, there is a strong demand for higher density circuit packaging. In the QFP, which is a typical semiconductor integrated circuit package, the terminal pitch is 0.5 mm or less, and recently, even 0.3 mm has been introduced.

With a pitch of 0.3 mm, the cross-sectional width of the terminal becomes as thin as about 0.12 to 0.15 mm, and the strength of the terminal is weak. Even if the terminal is put in the tray, the terminal may come into contact with the inner wall of the tray during transportation, When the terminal is touched, the terminal is deformed, which causes the floating of the bridge or the lead during mounting.

Further, when the pitch becomes fine, the reproducibility of cream solder printing also becomes poor, and the deterioration of mounting quality due to blurring or blurring becomes a problem. TAB mounting is used for mounting liquid crystal displays, but in the case of this TAB, the terminal thickness is normally as thin as 35 μm and the width is also
The thickness of the terminal is 0.1 mm or less, and the strength of the terminal is extremely weak, and it is taped until just before mounting, punched with a press at the time of mounting, and mounted as it is.

In any case, if the pitch becomes narrow, lead floating is likely to occur due to deformation of the bridge and terminals, and it has been regarded as the biggest problem in high-density mounting. An object of the present invention is to provide an electronic component, a method of manufacturing the electronic component, and a mounting method thereof that can obtain stable mounting quality even in high-density mounting.

[0008]

In the electronic component of the present invention, a plurality of terminals are connected by a connecting means made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material.

According to the present invention, it is possible to supply a high-density mounted electronic component to a circuit board in a stable shape and obtain stable mounting quality.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The electronic component according to claim 1 of the present invention is an electronic component having a plurality of terminals, which is made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material. Is provided with a connecting means for connecting the terminals to each other, and since the plurality of terminals are mechanically connected by the connecting means until the terminals are supplied to the circuit board, the mechanical strength of the terminals is increased. Also, it is less likely to change, and the flatness (coplanarity) of the mounting surface of the terminal is maintained, so stable mounting is possible. When melted in the reflow process, the surface tension separates the parts between the terminals and concentrates on the terminals. That is, a phenomenon similar to soldering in which solder is supplied from the periphery occurs, and as a result, the surface mounting operation is performed.

According to a second aspect of the present invention, in the electronic component according to the first aspect, the connecting means includes at least one of tin, lead, silver, bismuth, gold, indium and zinc. To do.

According to a third aspect of the present invention, in the electronic component according to the first aspect, flux is applied to at least a part of the plurality of terminals and the connecting means. According to a fourth aspect of the present invention, in the electronic component according to the first aspect, the plurality of terminals are formed by a lead frame or a TAB.

According to a fifth aspect of the present invention, in the electronic component according to the first aspect, the connecting means is a strip-shaped body, and a plurality of terminals are crimped and coupled to the strip-shaped body. In the electronic component according to claim 6 of the present invention, the thickness of the connecting means is 1
The feature is that it is more than a micrometer, and it is joined without applying cream solder printing or solder plating on the land of the substrate.

According to a seventh aspect of the present invention, in the electronic component according to the first aspect, the volume of the connecting means per terminal is not more than half the value obtained by multiplying the area of the land for mounting the terminal by the pitch thereof. It is characterized by

According to an eighth aspect of the present invention, in the electronic component according to the first aspect, which has terminals on at least two or more end faces, connecting means for connecting the terminals on each side are mutually connected. Is characterized by.

According to a ninth aspect of the present invention, in a method for manufacturing an electronic component, a plurality of terminals are connected to each other by connecting means of a band-shaped body made of a soft brazing material or a material containing a metal element forming a solid solution with soft brazing material. When manufacturing an electronic component, the terminals of a plurality of electronic components are crimped and coupled to the coupling means of the band-shaped body, and then the coupling means between the electronic components are cut to divide each electronic component. And

According to a tenth aspect of the present invention, there is provided a method of manufacturing an electronic component, wherein a plurality of terminals of an electronic component having a plurality of terminals formed by a lead frame or TAB are formed by using a soft solder material or a soft solder and a solid solution. When manufacturing an electronic component connected by a band-shaped connecting means made of a material containing a metal element to be formed, the terminals of a plurality of electronic components are crimped and connected to the band-shaped connecting means, and then the electronic parts are connected to each other. At the same time that the connecting means is cut, the lead frame or the TAB is cut to divide each electronic component.

According to an eleventh aspect of the present invention, there is provided a method for mounting an electronic component, wherein when mounting an electronic component having a plurality of terminals on a land of a circuit board, a soft brazing material or a metal element forming a solid solution with the soft brazing material is used. An electronic component is supplied to a circuit board in a state in which a plurality of terminals are connected to each other by a connecting means made of a material containing the material, and the connecting means is melted by heating to separate the portions between the terminals by surface tension and The individual terminals and the lands of the circuit board are soldered.

According to a twelfth aspect of the present invention, there is provided a method of mounting an electronic component, wherein a plurality of terminals of an electronic component having terminals on at least two or more end faces are made of a soft brazing material or a metal which forms a solid solution with a soft brazing material. When mounting electronic components that are connected by connecting means of strips made of a material containing elements on a substrate, use connecting means that connect the terminals on each side of the electronic parts to each other as the connecting means of the strips. Then, crimp the terminal of the electronic component to the connecting means of this strip to connect it,
The electronic parts are mounted by aligning the mutually connected parts of the connecting means with a waste land provided on the circuit board.

(First Embodiment) (a) and (b) of FIG.
(C) shows (Embodiment 1). First, in the electronic component 6, as shown in FIG. 1B, the ends of the plurality of terminals 8 of the electronic component body 7 are connected by a band-shaped solder sheet 9 as a connecting means. As shown in FIG. 1A, the solder sheet 9 is laid and the end portions of the terminals 8 are overlapped, and the end portions of the terminals 8 are pressed against the solder sheet 9 from above.

As a result, the soft solder sheet 9 was inserted into the end portion of the terminal 8 as shown in FIG. 1 (b) and could be easily crimped. The pitch of the terminals 8 of the electronic component body 7 used was 0.5 mm, the solder sheet 9 had a thickness of 50 μm, and the material was eutectic solder.

In the electronic component 6 thus manufactured, the plurality of terminals 8 are mechanically connected by the band-shaped solder sheet 9, so that the mechanical strength of the terminals is increased and
It also becomes difficult to change, and the flatness (coplanarity) of the mounting surface of the terminal is maintained, so stable mounting is possible.

The electronic component 6 is supplied onto the circuit board 1 so as to correspond to the land 2. When the solder sheet 9 is heated in this state, the solder sheet 9 is melted, and when the solder sheet 9 is melted, surface tension separates the portions between the terminals and concentrates on the terminals. That is, a phenomenon similar to soldering in which solder is supplied from the periphery occurs, and as a result, the electronic component body 7 is surface-mounted with the solder 9a as shown in FIG.

More specifically, the terminal 8 of the electronic component 6 shown in FIG. 1 (b) is placed on the land 2 on the circuit board 1 in a corresponding manner, and the terminal 8 is placed in a reflow furnace (not shown). When heated, the melted solder 9a of the solder sheet 9 is applied to the land 2 and the terminal 8
, The terminals 8 are aligned in the center of the land 2 by the self-alignment effect, and the solder amount is appropriate, so that a good mounting quality is obtained without generating a bridge.

The solder sheet 9 was used by applying a thin flux on the joint side with the circuit board 1. In this (Embodiment 1), the electronic components are mounted on the circuit board 1 using the reflow furnace, but the same effect can be expected by heating and melting the solder sheet 9 by another means.

(Embodiment 2) FIGS. 2 and 3 show (Embodiment 2). FIG. 3 shows the present invention implemented in TAB implementation. As described above, the terminal 8 of the TAB-formed electronic component body 7 is mechanically extremely weak and is deformed or cut by a small force, but in this (Embodiment 2), a 20 μm-thick strip-shaped body is used. The solder sheet 9 was used as a connecting means as shown in FIG.

The pitch of the terminals 8 is 0.2 mm, and the distance between the fine pitch terminals 8 is set (first embodiment).
Similarly, the solder sheet 9 is inserted into the end portion of the terminal 8 and pressure-bonded.

A thin flux was applied to the joint side of the solder sheet 9 with the circuit board 1 to ensure wettability during mounting. In this case, the joining with the circuit board 1 was performed by pressing with a hot iron kept at a constant temperature. There were no bridges, the shape of the joint fillet was good, and stable mounting quality was obtained.

(Third Embodiment) FIG. 3 shows a third embodiment.
Is shown. Electronic parts such as QFP with terminals on four sides are increasing. In this case, the terminals of each side are mechanically connected to each other using the strip-shaped solder sheet 9 as in the above embodiment.

At this time, as shown in FIG. 3, mechanical strength is obtained by connecting the band-shaped solder sheets 9 on each side and connecting them together at the connecting points 9b so as to surround the outer periphery. Increased and great effect. A thin flux was applied to the joint side of the solder sheet 9 with the circuit board 1 to ensure wettability during mounting.

In the case of the electronic component 6 thus constructed, when it is mounted on the circuit board 1, the amount of solder is too large for the outermost terminal of each side, and a bridge is apt to occur. In the mounting method of 3), the discarding lands 2a are provided at the mounting positions of the electronic components 6 on the circuit board 1 respectively corresponding to the connection points 9b, and excess solder is generated when the solder sheet 9 is melted and mounted. A better mounting quality is secured by absorbing the land 2a so that it is attached.

In each of the above-mentioned embodiments, the electronic parts 6 in which the terminals are connected by the solder sheet 9 as the connecting means are separately manufactured, and are supplied to the circuit board 1 to be mounted. In the case of a lead frame or a TAB, it is more convenient to attach a large number of electronic components to a long continuous body and cut and divide them before shipping inspection or mounting, and the connecting means of the present invention is also used. It is convenient because they are installed all at once, and simple equipment can be achieved by continuously crimping the solder sheets. In this case, the connecting means of the solder sheet 9 can be divided at the same time by pressing when cutting the lead frame or TAB, which is efficient.

According to each of the above-described embodiments, so-called soldering is possible in principle even on a land that has not been previously solder-plated or cream-solder printed, but the surface irregularities of the terminals make it smooth like a glass substrate. Adhesive strength could not be obtained even with respect to other surfaces unless the connecting means had a thickness of 1 micrometer or more. Further, the thicker the connecting means, the easier the joining, but if it was too thick, many bridges occurred. It has been confirmed that the volume of the connecting means per terminal is preferably half or less of the value obtained by multiplying the land area by the pitch in order to fully bring out the effect of the present invention.

In each of the above-mentioned embodiments, eutectic solder is used as the material for the band-shaped solder sheet 9, but it melts when it is brazed by heating and forms a solid solution with the brazing material. The same effect can be expected even if it is composed of silver-containing solder, a low-melting soft solder material, or a material containing at least one metal element such as tin, lead, silver, gold, or bismuth that forms a solid solution with soft solder. .

In each of the above-mentioned embodiments, the surface of the solder sheet 9 which faces the substrate is coated with flux, but the flux is applied to the terminals 8 and at least a part of the connecting means. Should be applied. Of course, if the land surface is clean, it can be joined without flux.

[0036]

As described above, the electronic component of the present invention is an electronic component having a plurality of terminals and is made of a soft brazing material or a material containing a metal element that forms a solid solution with the soft brazing material. It is characterized in that a connecting means for connecting is provided, and since the plurality of terminals are mechanically connected by the connecting means, stable mounting is possible. Also,
The connecting means is melted at the time of mounting and used for soldering.

In an electronic component having terminals on at least two or more end faces, when connecting means for connecting the terminals on each side are mutually connected, an electronic component having terminals on four sides such as QFP may also be used. Can be installed stably.

The method of manufacturing an electronic component according to the present invention is used for manufacturing an electronic component in which a plurality of terminals are connected to each other by the connecting means of the band-shaped body made of the soft brazing material or the material containing the metal element forming the solid solution with the soft brazing material. The electronic device of the present invention is characterized in that the terminals of a plurality of electronic components are crimped and connected to the connecting member of the belt-like body, and then the connecting device between the electronic components is cut to divide each electronic component. Parts can be produced efficiently.

Further, terminals of a plurality of electronic parts are crimped and connected to the connecting means of the band-shaped body, and thereafter, the connecting means between the electronic parts are cut off, and at the same time, the lead frame or the TAB is cut off. When divided into electronic parts, the production efficiency can be further improved.

The electronic component mounting method of the present invention is made of a soft brazing material or a material containing a metal element that forms a solid solution with a soft brazing material when mounting an electronic component having a plurality of terminals on a land of a circuit board. An electronic component is supplied to a circuit board in a state where a plurality of terminals are connected by a connecting means, and the connecting means is melted by heating to separate the portions between the terminals by surface tension and the plurality of terminals. It is characterized by soldering with the land of the circuit board, and stable mounting is possible.

Further, a plurality of terminals of an electronic component having terminals on at least two or more end faces are connected to each other by a band-shaped connecting means made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material. When mounting the electronic component on the board, the connecting means for connecting the terminals on each side of the electronic component are connected to each other as the connecting means for the belt-shaped body, and the terminal of the electronic component is connected to the connecting means for the belt-shaped body. When electronic parts are mounted by crimping and connecting, and the mutually connected portions of the connecting means are aligned with the waste land provided on the circuit board, the connecting means melts and the electronic parts are connected to the circuit board. Excess material not required for soldering can be absorbed by the land, and better mounting quality can be secured.

[Brief description of drawings]

FIG. 1 is a perspective view of a manufacturing process of an electronic component and a mounting completion state on a circuit board according to a first embodiment.

FIG. 2 is a perspective view of an electronic component according to a second embodiment.

FIG. 3 is a perspective view before completion of mounting on a circuit board according to a third embodiment.

FIG. 4 is an explanatory diagram of a conventional mounting method.

[Explanation of symbols]

 1 Circuit Board 2 Land 2a Discarded Land 6 Electronic Component 7 Electronic Component Main Body 8 Terminal 9 Solder Sheet [Connecting Means] 9a Solder 9b Connecting Point

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshio Maruyama 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (12)

[Claims] 1. An electronic component having a plurality of terminals, the electronic component comprising a soft brazing material or a material containing a metal element that forms a solid solution with the soft brazing material and provided with a coupling means for coupling the plurality of terminals. 2. The connecting means is tin, lead, silver, bismuth,
The electronic component according to claim 1, comprising at least one of gold, indium, and zinc. 3. The electronic component according to claim 1, wherein a flux is applied to at least a part of the plurality of terminals and the connecting means. 4. A lead frame or T having a plurality of terminals.
The electronic component according to claim 1, which is formed of AB. 5. The electronic component according to claim 1, wherein the connecting means is a band-shaped body, and a plurality of terminals are pressure-bonded to the band-shaped body to be connected. 6. The electronic component according to claim 1, wherein the connection means has a thickness of 1 μm or more, which enables bonding without performing cream solder printing or solder plating on the lands of the circuit board. 7. The electronic component according to claim 1, wherein the volume of the connecting means per terminal is not more than half the value obtained by multiplying the area of the land on which the terminal is mounted by its pitch. 8. The electronic component according to claim 1, wherein in the electronic component having terminals on at least two or more end faces, connecting means for connecting the terminals on each side are connected to each other. 9. When manufacturing an electronic component in which a plurality of terminals are connected by a connecting means of a band-shaped body made of a soft brazing material or a material containing a metal element forming a solid solution with a soft brazing material, a plurality of connecting means for the band-shaped body are used. The method of manufacturing an electronic component, wherein the terminals of the electronic component are crimped and connected to each other, and then the connecting means between the electronic components are cut to be divided into the electronic components. 10. A connecting means for connecting a plurality of terminals of an electronic component having a plurality of terminals formed by a lead frame or a TAB with a band made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material. When manufacturing an electronic component connected by, the terminals of a plurality of electronic components are crimped and connected to the connecting means of the band-shaped body, and then the connecting means between the electronic parts are cut and at the same time the lead frame or the TAB is cut. The manufacturing method of the electronic component which implement | achieves and divide | segments into each electronic component. 11. When mounting an electronic component having a plurality of terminals on a land of a circuit board, the plurality of terminals are connected by a connecting means made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material. In this state, an electronic component is supplied to the circuit board, heated to melt the connecting means, separate the portions between the terminals by surface tension, and solder the plurality of terminals to the land of the circuit board. How to mount parts. 12. A plurality of terminals of an electronic component having terminals on at least two or more end faces are connected to each other by a band-shaped connecting means made of a soft brazing material or a material containing a metal element forming a solid solution with the soft brazing material. When mounting the electronic component on the circuit board, the connecting means for connecting the terminals on each side of the electronic component are mutually connected as the connecting means for the belt-shaped body, and the terminal of the electronic component is connected to the connecting means for the belt-shaped body. A method for mounting an electronic component, which comprises crimping and coupling, and aligning the mutually coupled portions of the coupling means with a waste land provided on a circuit board to mount an electronic component.