JPS5842784B2 - solder cutting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solder cutting device, particularly a solder cutting device E suitable for manufacturing minute solder pieces.

One of the assembling processes for semiconductor devices is a semiconductor substrate bonding process in which a semiconductor substrate is bonded to a substrate support called a header or a lead frame, and in this process, a bonding method using solder is often adopted.

Among these, there is a method of bonding the semiconductor substrate to the substrate support by placing a foil-shaped solder at a predetermined position on the substrate support, and then placing the semiconductor substrate on top of the solder and melting the solder with force. is often used.

With this method, the thickness and external dimensions of the foil-shaped solder used can be easily and accurately controlled depending on the packaging. Compared to the method of bonding semiconductor substrates by dropping drops at separate positions and supplying the droplets to the semiconductor substrate bonding section, this method has less variation in the amount of solder and is suitable for bonding minute semiconductor substrates.

By the way, in order to obtain a certain amount of solder by controlling the thickness and external dimensions, for example, a strip of solder having a certain thickness and width is cut into a certain length f using a solder cutting device equipped with a cutting blade. ing.

However, in this method, the cutting blade, which is the main component of the cutting device, gradually wears out as the number of cutting operations increases, and the accuracy in controlling the amount of solder to be cut decreases.

Therefore, it has been necessary to constantly maintain and maintain the solder cutting blade.

An object of the present invention is to provide a solder cutting device that eliminates the unavoidable maintenance of the cutting blade in conventional solder cutting devices, has good workability, and can always cut a certain amount of solder. It is.

Next, an embodiment of the solder cutting device according to the present invention will be described with reference to the drawings.

The solder cutting device of the present invention, as shown in a schematic diagram in FIG.
, a pull-out mechanism C that pulls out a predetermined length of solder foil from this solder foil holding mechanism, a fusing mechanism that heats and fuses the solder foil, and a transfer mechanism E that transports the fused solder foil to a desired position. It is made up of.

In the solder supply mechanism A, the strip-shaped solder foil 1 is connected to the IJ-ru 2I.
It has the function of continuously supplying solder foil 1 by rotating the reel 2.

The solder foil holding mechanism B consists of a lower glass plate 3 in which a guide groove is formed, an upper glass plate 4 located above the lower glass plate 3, and a predetermined clamping force between the two glass plates by pressing the upper glass plate downward. It is composed of a screw 5 for generating and a screw holder 6 for holding the same, and has the function of holding the solder foil 1 supplied from the solder supply mechanism by sandwiching it between two glass plates 3 and 4.

Note that these glass plates 3 and 4 are arranged in a stacked manner on a fixing table 3'.

The pull-out mechanism C is composed of a lower clamper 7 and an upper clamper 8, and these two clampers 7°8 move toward the solder foil holding mechanism to sandwich the solder foil, and then return to their original positions. After the solder foil is pulled out by a predetermined length and the solder foil is fused to a predetermined size, the upper clamper 8 is operated to move upward and horizontally.

The fusing mechanism consists of nichrome wire 1 wound around spinning wheels 9 and 9'.
0 and electrodes 11 and 11';
11' (This has the function of applying electricity to the nichrome wire 10 to generate heat and instantly melt the solder foil.

Further, the transfer mechanism E includes a vacuum chuck 1 connected to the vacuum thread.
2, which is cut by a cutting mechanism, has the function of adsorbing the solder foil located on the upper part of the lower clamper 8, and transporting it to a predetermined position.

The movements of the pull-out mechanism, fusing mechanism, and transfer mechanism are controlled by a so-called timing cam installed on the same axle.

By the way, according to the uninvented cutting device comprising the above machine, the solder foil is cut and transferred in the following manner.

First, as shown in FIG. 1, the strip-shaped solder foil 1 supplied from the reel 2 is led out through a guide groove provided in the lower glass plate 3 with its tip end toward the side where the clamper is arranged, and then placed on the upper glass plate 4. Apply appropriate pressure.

Next, as shown in Figure 2, the clamper 7.8 moves in the direction of the arrow and approaches the solder foil holding mechanism, and the third
As shown in the figure, the ends of the solder foil 1 are held together.

A vacuum suction hole 13 is formed in the lower clamper 8, and the clamped solder foil is sucked with a predetermined suction force.

After this, the clamper 7.8 moves to its original position and pulls out the solder foil by a predetermined length.

When this attack is established, the fusing mechanism is activated, and the nichrome wire heater 10 that generates heat rises as shown in FIG. 4, contacts the solder foil, and melts the solder foil.

FIG. 5 shows the solder foil immediately after such fusing, and since the solder foil is instantly fused, the solder foil is not significantly deformed by the fusing.

After the melt is blown in this way, as shown in FIG. Suction by the vacuum suction hole 13 provided in the clamper 7 is stopped, and the vacuum chuck 12 attracts the melted solder foil piece and transfers it to a predetermined position, that is, onto the substrate support.

At this time, the nichrome wire heater 10 descends downward and returns to its original state.

Incidentally, the nichrome wire heater used in the apparatus of the present invention also deteriorates as the number of fusing operations increases, similar to the cutting blade of the conventional apparatus.

However, if the nichrome wire located on the electrodes 9, 9' is wound onto the spinning wheel 11 when the number of fusing times reaches a predetermined value, the new nichrome wire wound on the spinning wheel 11' will be wound between the electrodes 9, 9'. automatically supplied.

Therefore, by winding a long length of nichrome wire around one of the spinning wheels 11', the nichrome wire does not have to be replaced frequently (it does not require a long time to hold and maintain it like a cutting device with a cutting blade). It disappears.

Thus, by using the solder cutting device according to the present invention, a certain amount of solder can always be secured with high accuracy, and the bonding of the semiconductor substrate to the substrate support can be performed reliably.

In addition, although a strip-shaped solder foil piece was used in the embodiment, the solder cutting device of the present invention also uses wire method solder tζ, since the cutting effect is impaired by changing the wire diameter of the nichrome wire according to the diameter l. No, it can be applied.

As explained above, the solder cutting device of the present invention is capable of automatically feeding, cutting, and transferring solder, and furthermore, maintenance work is extremely simple, and the solder cutting device of the present invention is capable of performing high-precision solder cutting at all times. It can be cut and has excellent industrial effects.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a solder cutting device according to an embodiment of the present invention, and Figs. 2 to 6 are cross-sectional views of solder foil being cut using the solder cutting device according to an embodiment of the present invention. It is. A...Solder supply mechanism, B...Solder holding mechanism, C...Drawer mechanism, D...
Fusing mechanism, E... Transfer mechanism, 1... Solder foil, 2... Reel, 3... Lower glass plate, 3'... ...Fixing base, 4...Upper glass plate, 5...Screw, 6...Screw holder, 7...Lower clamper 8... ...
Upper flumper 9, 9'...Spinning wheel, 10...
... Nichrome wire, 11,11' ... Electrode,
12... Vacuum chuck, 13... Vacuum suction element

Claims (1)

[Claims] 1. A solder supply mechanism that supplies solder in strips or lines, a solder holding mechanism equipped with a guide for positioning the solder and located in front of the solder feeder groove, and pulling out the solder in front of the solder holding mechanism. A fusing mechanism for heating and fusing the solder, comprising a pull-out mechanism and a resistance wire winding means that winds up a resistance wire and both ends of the resistance wire and energizes a predetermined length of the resistance wire to generate self-heating. A solder cutting device comprising: a transfer mechanism that sucks and holds the melted solder and transfers it to a predetermined position.