JPH0376780B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a technique that is effective when applied to the removal of resin burrs in the manufacturing process of resin-sealed semiconductor devices.

[Background technology]

Resin-sealed semiconductor devices usually use a multi-lead lead frame, and after attaching a pellet to each pellet attachment part and wire bonding the pellet to the inner end of the lead, a mold is used to form the package. It is completed by forming a mold and finally forming a lead.

The molding of the package is carried out by sandwiching the lead frame between the upper mold and the lower mold so that the pellet is located in the center of the mold cavity.
This is done by injecting resin such as epoxy resin at high pressure into the mold cavity. The lead frame is held between the upper and lower molds so that the peripheral edge of the mold cavity is located inside the tie bar, so a gap with a depth up to the tie bar is formed between the leads. Become. Therefore, when resin is injected to mold the package cage, resin with approximately the same thickness as the lead inevitably protrudes from the package side edge to the tie bar that functions as a dam, resulting in the formation of resin burrs inside the dam. .

Additionally, since the resin is injected under extremely high pressure, the resin gets into the tiny gap between the lead surface and the mold, forming resin flash burrs, which are resin burrs thinly coated on the lead surface. .

The resin burrs are usually removed before the lead forming process because they cause damage to the tie bar cutting mold, interfere with the solder coating of the leads, and also cause poor appearance of the semiconductor device.

Resin burrs can be removed by, for example, injecting high-pressure water from a nozzle to a predetermined area.
It is explained in detail in No. 135646 and Japanese Patent Application Laid-open No. 149172/1983.

By the way, in each of the above-mentioned technologies, high-pressure water is used to process a molded lead frame in the length direction of a semiconductor device in which leads are formed on all sides, such as a so-called flat package type semiconductor device. In order to remove resin burrs by moving, even if a pair of nozzles is installed at a position where both sides of the package can be sprayed, for example, each nozzle can be eccentrically set by more than half the width of the package. It is necessary to have a structure in which the high-pressure water from each nozzle is widely diffused to a position exceeding at least one-half of the package width.

This is because if the above pair of nozzles is used,
Even if the nozzle is fixed, resin burrs on the package cage side end in the length direction of the lead frame can be sufficiently removed. This is because high-pressure water cannot be removed unless the high-pressure water reaches a position exceeding 1/2 of the length (in the length direction).

The same can be said of the technique described in Japanese Patent Application Laid-Open No. 57-54100, which removes burrs caused by machining.

From the above, in each of the above-mentioned technologies, for example, by applying an eccentric rotation of more than half the package width to the nozzle, it is possible to remove resin burrs from the entire lead frame on all four sides. In this case, high-pressure water is inevitably sprayed over the entire top surface of the package. Therefore, there is a problem in that defects are likely to occur in the package or its interior due to the impact of the high-pressure water. Furthermore, the inventors have found that there is a problem in that the efficiency is extremely low because high-pressure water is injected over a wider range than necessary.

[Purpose of the invention]

An object of the present invention is to provide an effective technology that can be applied to improve workability, work accuracy, and reliability of semiconductor devices regarding resin burr removal in the manufacturing process of resin-sealed semiconductor devices.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

That is, by providing a resin burr removal device equipped with a high-pressure fluid jetting means with an XY-direction drive means applied to the molded lead frame, the lead frame can be moved in any direction. It becomes possible to efficiently inject high-pressure fluid only to the target area without applying a large eccentric rotation to the target area, and the above object is achieved.

〔Example〕

FIG. 1 is a conceptual diagram showing a resin burr removal device according to an embodiment of the present invention.

That is, the deburring tank 1 is equipped with a high-pressure water injection device 3 directly connected to a high-pressure pump 2, and a lower part of the injection device 3 is capable of eccentric rotation by a motor 4 as schematically shown in FIG. The nozzle 5 is attached as shown.

An XY table 6 that also serves as a lead frame support is provided below the injection device 3 and is directly connected to the XY drive section 7. As shown in a partially cutaway view, the XY table 6 has a recess into which the molded lead frame 8 fits.

The operation of the XY table 6 is freely controlled by a control device 9 connected to an XY drive section.

FIG. 3 is a partial plan view of a molded lead frame showing the state in which resin burrs occur.

That is, around the four sides of the package 10, there are leads 1, some of which are buried inside the package 10.
The resin burrs are formed around the package 10 and inside the tie bars 12, which function as dams, as in-dam resin burrs 13, so as to close the gaps. It is something that

Further, as another resin burr, there is a resin flash burr 14 thinly deposited on the surface of the lead 11.

FIG. 4 shows an example of a reasonable scanning locus 15 of the nozzle 5 in a schematic plan view of the molded lead frame 8.

As shown in FIG. 3, since resin burrs are formed around the package 10, it is desirable to move the nozzle 5 along the periphery of the package 10 as much as possible even in the state of the lead frame. .

Also, as shown in FIG. 3, since the resin burrs 13 and 14 in the dam have a certain width, it is more effective to give the nozzle a small eccentric rotation to finely change the injection center of gravity. It is true.

Since the resin burr removal device of this embodiment has a function that satisfies the above requirements, it is possible to move the nozzle 5 while rotating it with a predetermined eccentric width in the direction of the arrow of the trajectory 15 shown in FIG. Therefore, wasteful movement of the nozzle 5 can be eliminated and high-pressure water can be selectively injected only to the target area, improving work efficiency and reliably removing resin burrs, improving work accuracy. You can also improve your skills.

Furthermore, since the spray can be prevented from being sprayed onto unnecessary parts, it is possible to prevent damage to the semiconductor device and bending of the leads.

〔effect〕

(1) By providing a means for driving the molded lead frame in the XY directions, the lead frame can be moved in any direction, thereby increasing efficiency without giving large eccentric rotation to the nozzle of the high-pressure fluid injection means. High-pressure fluid can be effectively injected to the target area.

(2) The high-pressure fluid injection means has a nozzle that can rotate eccentrically, and in view of the effect of (1) above, it is possible to finely change the center of gravity of the injection by applying a small eccentric rotation to the nozzle. It is possible to eliminate unnecessary movement and selectively inject high-pressure fluid only to the target area.

(3) According to (1) and (2) above, unnecessary movement of the nozzle can be eliminated, so that work efficiency can be improved.

(4) With (1) and (2) above, the accuracy of deburring work can be improved.

(5) With (1) and (2) above, it is possible to prevent the injection of high-pressure fluid to unnecessary parts, so it is possible to prevent damage to the inside of the package and lead bending, etc.
Reliability can be improved, and high-pressure fluid can be used, and from this point of view as well, deburring workability can be improved.

(6) By providing two or more high-pressure fluid injection means, it can be applied to a plurality of molded lead frames at the same time.

(7) By using two types of high-pressure fluid spraying means that can spray the molded lead frame from both above and below, resin burrs can be removed without reversing the lead frame.

(8) By using water as the high-pressure fluid, clean deburring can be achieved.

(9) Resin burr removal ability can be improved by mixing powder with water or other liquids.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the Examples described above, and it is understood that various changes can be made without departing from the gist of the invention. Needless to say.

For example, although only water is used as the high-pressure fluid, it is not limited to this; other liquids may be used as the high-pressure fluid, or water or powder mixed with the liquid may also be used. Furthermore, it may be a high-pressure gas fluid in which powder is mixed with gas such as air.

[Application field]

In the above explanation, the invention made by the present inventor was mainly applied to a so-called flat package type semiconductor device, which is the background field of application, but the present invention is not limited to this, for example. This is an effective technique that can be applied to any semiconductor device as long as the package is formed by resin molding.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing a resin burr removal device according to an embodiment of the present invention, FIG. 2 is a partial front view showing a nozzle used in the device of this embodiment, and FIG. 3 is a diagram showing the occurrence of resin burrs. FIG. 4, which is a partial plan view of the mold-completed lead frame showing the state, is an explanatory diagram showing the locus of the nozzle when the apparatus of this embodiment is applied to the mold-completed lead frame. 1...Deburring tank, 2...High pressure pump, 3...
High pressure water injection device, 4...Motor, 5...Nozzle,
6...XY table, 7...XY drive section, 8...
Molded lead frame, 9...control device,
10...package, 11...lead, 12...
Tie bar, 13...Resin burr in the dam, 14...
Resin flash variation, 15...trajectory.

Claims (1)

[Scope of Claims] 1. An apparatus for removing resin burrs generated on resin-sealed semiconductor devices, comprising a high-pressure fluid injection means having an eccentrically rotatable nozzle, and means for driving a molded lead frame in XY directions. Resin burr removal equipment. 2 Lead frame movement using XY direction drive means
The movement in the XY direction causes the high-pressure fluid jetting means to intensively jet the high-pressure fluid along the outer periphery of the package of the resin-sealed semiconductor device. Resin burr removal equipment. 3. The resin burr removal device according to claim 1, wherein the resin burr is at least one of a resin burr in a dam of a lead frame or a resin flash burr near the outer periphery of a package of a resin-sealed semiconductor device. . 4. The resin burr removal device according to claim 1, characterized in that a plurality of high-pressure fluid injection means are provided. 5. The resin burr removal device according to claim 1, characterized in that the high-pressure fluid injection means is provided with two types of downward injection and upward injection. 6. The resin burr removal device according to claim 1, wherein the high-pressure fluid is composed of water or powder-mixed water. 7. The resin burr removal device according to claim 1, wherein the high-pressure fluid is composed of powder-mixed air. 8. The resin burr removal device according to claim 1, wherein the XY direction driving means is an XY table.