JPS6155872A - Soldering structure of multiterminal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Tangoritatsu Saranijo... This invention relates to a large number of W, film-like terminals formed on a HIIAEL matrix type display panel, etc., and external terminals corresponding to these terminals. This invention relates to a soldering structure in which flexible lead terminals are electrically and mechanically connected and fixed.

Traditional standing technique ff1lj! EL and liquid crystal matrix display panels have a large number of matrix-type electrode terminals formed in series at minute pitches on a glass substrate, and each of these many terminals has a terminal formed on a separate flexible lead substrate. It is common to take out the electrodes externally by soldering.

For example, the general structure of a thin IIEL matrix type display panel will be explained with reference to FIGS. 10 to 13.

In addition, Fig. 10 is a cross-sectional view, the left half is a cross-sectional view in the X direction, and the right half is a cross-sectional view in the Y direction.
is a transparent glass substrate, (2) is a matrix type EL element formed on the glass substrate (1), and (3) is a glass substrate (
1) A glass back plate (cover glass) on which the EL element (2) is hermetically sealed, and (4) a flexible lead member for taking out the electrodes of the EL element (2) to the outside. EL element (2
) in (5) is 1. on the glass substrate (1). 'l',
(6) is a transparent first insulating layer such as Y2O3 that covers the transparent electrode (5); (7)
(8) is a light emitting layer (phosphor) such as ZnS:Mn formed on the first insulating layer (6), and (8) is a Y2O3 layer covering the light emitting layer (7).
The transparent second insulating layer (9) is a back electrode made of an Al vapor-deposited film formed on the second insulating layer (8) in a number of stripes at a predetermined pitch in the Y direction perpendicular to the transparent electrode (5). be.

One end of each electrode (5), (9) of the EL element (2) is formed to extend above the peripheral part of the glass substrate (1), and a back plate (3) is formed to cross a part of this electrode end. is fixed on the glass substrate (1) via an insulating sealant (10) such as epoxy resin, and then a moisture-proof material (1) such as silicone oil is placed between the back Fi (3) and the EL element (2). It will be discussed first.

The flexible lead member (4) has a large number of conductive 1!5i! The conductive film (13) (hereinafter referred to as the second terminal (b)) around the back surface of the insulating substrate (12) is formed in a series at a minute pitch around the top surface of the glass substrate (1). The ends of each electrode (5) and (9) lined up (hereinafter referred to as the first terminal (a))
Correspondingly, each of the corresponding first and second @ elements (a) and (b) are electrically and mechanically connected and fixed via solder (14). This soldering is carried out by first depositing a certain amount of preliminary solder (14') on the second terminal (b) by electroplating or the like, as shown in Fig. 13, for example.
) and the first terminal (a) are placed on the glass substrate (1) so that the first terminal (a) overlaps with the preliminary solder (14”) interposed therebetween.
4) are aligned and stacked, the whole is pressurized with uniform force, and the preliminary solder (14') is melted by infrared heating (Japanese Patent Publication No. 5G-2157, Japanese Patent Publication No. 59-1982).
14872).

° Problem to be solved φ In order to properly solder the two terminals (a) and (b) above, an appropriate static pressure of 71 is applied when heating and melting the preliminary solder (14'), but this pressurizing force is , there are hundreds of first terminals (a) and second terminals (b), and since the soldering part is long, the glass substrate (1) and the flexible lead member (
4) are difficult to align, the flexible lead member (4) is soft, and the boards (1) and (12) are warped. Insufficient adhesive strength of (a) and (b),
Poor conductivity occurs, and on the other hand, in areas where the pressure is too large, a large amount of solder protrudes from both sides of the two terminals (a) and (b) as shown by the chain lines in Figure 12, and this protruding solder (
14") could cause a short circuit due to solder protruding from between adjacent terminals. This short circuit accident has increased as terminal pinches have recently become smaller and smaller, below 0.4W+++, and this has resulted in poor product yields. Also, as mentioned above, when soldering the two terminals (a) and (b), it was difficult to control the pressure applied to the heating R of the preliminary solder (14').
Soldering workability was poor, requiring high precision and expensive soldering equipment.

Means for Solving the Problems A technical means for solving the above problems of the present invention is to provide a plurality of first terminals formed with minute pinches on a first insulating substrate, and a plurality of first terminals formed on a second insulating substrate. A correspondingly large number of second
In the device in which the terminals are soldered, a spacer is embedded in the solder between the first terminal and the second terminal to prevent the solder from protruding.

The spacer using this technical means is generally made of metal particles, insulator particles, etc., and is interposed between the first and second terminals to prevent solder from protruding between the first and second terminals. Since the first and second terminals are always connected with solder of a constant thickness, soldering with good contact strength and conductivity can be performed.

In addition, the first and second terminals are soldered by applying pressure and heating to the preliminary solder between them, but even if the pressure is sufficiently increased, the amount of solder that protrudes from between the two terminals due to the spacer is small. This prevents short-circuit accidents between adjacent terminals. Furthermore, the spacer makes it easier to control the pressure during soldering, making the soldering work easier.

An embodiment in which the present invention is applied to a multi-terminal soldering structure of a thin IQEL matrix type display panel shown in Fig. 1[theta] of the brain assembly will be described with reference to Figs. 1 and 2.

Note that Figure 1 is a cross-sectional view, and the left half is a cross-sectional view in the X direction.
The right half shows a cross-sectional view in the Y direction. The features of this embodiment are:
In the solder (14) at the ends of the first terminal (a) and the second terminal (b), a spacer (15) with a particle diameter of about 100 mm is embedded to prevent the solder (14) from protruding due to heating and pressurization. That's true.

Note that the same parts in FIGS. 1 and 2 as in FIG. 10 are designated by the same reference numerals, and explanations thereof will be omitted.

The spacer (15) is made of metal particles that are compatible with the solder 1, insulating particles such as glass, or coated with a metal film such as gold or tin that is compatible with solder on the surface of the insulating particles. A set of first and second terminals (a) with particle size
, (b). This spacer (15)
The particle size is set to the solder thickness (approximately 20 μl) when the first and second terminals (a) and (b) are soldered well. Soldering of the first and second terminals (a) and (b) using such a spacer (15) is performed as shown in FIGS. 3 to 6, for example.
This is carried out in the manner shown in FIG.

To explain the cases shown in FIGS. 3 to 6, first, as shown in FIG. 3, each first terminal (
b) Form a preliminary solder (14°) on top, press this first terminal (b) onto a flat platform (16) dotted with a number of spacers (15), and then pull it up. Then the fourth
As shown in the figure, the spacer (15) slightly bites into and adheres to the preliminary solder (14') of the first terminal (b). At this time, spacers (15) are also placed on the flexible insulating substrate (12).
) may be slightly attached. Assuming that the spacer (15) is a so-called conductive particle, which is a metal particle or an insulator particle whose surface is coated with a metal, then the spacer (15) attached to the insulating substrate (12) as shown in FIG.
) only by an air blow method, etc., and then connect the corresponding second terminal (b) on the first terminal (a) of the glass substrate (1) with a spacer (15) and preliminary solder as shown in Fig. 6. (14
'). Then, the preliminary solder (14'') is heated and melted with an infrared lamp or the like while being pressurized, and the first and second terminals (a) and (b) are soldered.

The pressure during this soldering should be large enough to prevent the spacer (15) from being crushed;
) enters the melted preliminary solder (14"), and the first and second
The solder thickness between the terminals (a) and (b) is controlled so that it does not become less than the grain size of the spacer (15). By regulating the solder thickness, the amount of solder protruding from both sides of the first and second terminals (a) and (b) is suppressed, thereby eliminating the occurrence of short-circuit accidents between adjacent terminals. Also, the first and second terminals (a), (b
) are connected with solder (14) of constant W and D, so that the soldering has good adhesive strength and conductivity. Furthermore, during this soldering process, the pressure applied when heating the preliminary half H-1 (14') can be made sufficiently large to the extent that the spacer (15) is not crushed, making delicate pressure control unnecessary. Moreover, since there is no problem even if there are local variations in the applied pressure, soldering is easy and can be performed with simple equipment. Furthermore, if conductive particles are used for the spacer (15), this spacer (15) also connects the first and second terminals (a) and (b), so the first and second terminals (a) and (b)
The conductivity between the two becomes even better.

Next, the cases shown in FIGS. 7 to 9 will be explained. First, as shown in FIG. 7, flux (17) is applied onto the preliminary solder (14') of the second terminal (b).

Flux (17) is the first. The soldering of the second terminals (a) and (b) is to improve the soldering properties, and a material with sufficient adhesiveness is used. Next, the spacer (1) is inserted from above the flexible lead member (4) with the second terminal (b) side facing up.
5) Hula.

Spray the spacer (17) onto the flux (17) and use its adhesive force to place the spacer (17) on the flux (17) as shown in Figure 8.
If the zero-order spacer (15) to which 5) is attached is a conductive particle, the spacer (15) attached to a surface other than the flux (17) may be
15) using an air blow method, etc., and connect the first and second terminals (a) and (b) with spacers (as shown in Figure 9).
15), Flux (17), Reserve Half 01 (14'
) and heat under pressure. This soldering is performed in the same way as the soldering shown in FIG. 6, since the flux (17) is evaporated by heating.

Above space! ) When insulating particles such as glass or ceramic are used in (15), the step of selectively removing spacers by air blowing in the above manufacturing process is not necessarily necessary.

Further, the spacer (15) is attached on the first terminal (a) on the glass substrate (1), and the first) second terminal (a),
(b) may be connected by soldering.

The present invention can be similarly applied to polygon soldering structures such as spray panels, plasma panels, display panels, etc. other than the WIIQEL matrix type display panel.

According to the present invention, even if a large number of optical units are arranged at a minute pitch and soldered by first end pressure heating, there will be no short-circuit between the terminals due to solder protruding from both terminals m1 due to the spacer. Soldering is always done well and with uniform strength using a constant thickness of solder.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a thin 1) EL matrix type display panel having a soldering structure according to the present invention, the left half is a cross-sectional view in the X direction, the right half is a cross-sectional view in the Y direction, and FIG. 71-T in the figure, an enlarged cross-sectional view taken along the line 71-T, and FIGS. The cross-sectional view, Figure 1θ, is a cross-sectional view of a general thin film EL matrix type display panel, the left half is a cross-sectional view in the X direction, the right half is a cross-sectional view in the Y direction, and the 1st) figure is a cross-sectional view of the display panel in Figure 10. A partial plan view of the panel, Figure 12, is the T of Figure 10! T2rA
FIG. 13 is an enlarged cross-sectional view along FIG. 12 before soldering. (L) -First insulating substrate (glass substrate), (12)-
・-・Second insulating substrate, (a) ・-1st f4 child, (b
) ・-・fS2 terminal, (1, 1)・-・Solder, (1
5) −・−・Spacer.

Claims (1)

[Claims] (1) A device in which a large number of first terminals formed at a minute pitch on a first insulating substrate and a large number of second terminals formed on a second insulating substrate corresponding to the first terminals are soldered,
A multi-terminal soldering structure, characterized in that a spacer is embedded in the solder between the first terminal and the second terminal to prevent the solder from protruding.