JPH1074878A - Device and method for manufacturing of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a tie bar cutting device against damages by a method, wherein the shape of a package which partially covers a lead is checked in such a state that a tie bar is located adjacent to the package, the package is judged to be good when the check result indicates that the package is acceptable, and the tie bar of only a semiconductor device possessing a package of good shape is cut off. SOLUTION: A lead frame 1 is transferred by a transfer means moving on a guide rail to tie bar cutting means 4u and 4d which cut off a tie bar 1a. At this point, a detecting means or a photosensor 5a, located above the transfer means detects whether or not a mark is attached to a resin-encapsulated semiconductor device 2. The mark is previously attached to the resin-encapsulated semiconductor device 2 for discriminating between defective and acceptable, when the state of sealing resin is checked after the device 2 has been encapsulated with the sealing resin. Here, a mark is attached to a defective product. A detection result outputted from the photosensor 5a is sent to a tie bar cutting means 4, only the tie bar 1a of the semiconductor device 2 whose encapsulating resin is in an acceptable state is cut off by the tie bar cutting means, and the tie bars of the other semiconductor devices are not cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufacturing apparatus for cutting a tie bar connecting leads of a semiconductor device, and a method of manufacturing the semiconductor device.

[0002]

2. Description of the Related Art A semiconductor package is provided for protecting a semiconductor chip mounted on a lead frame, a wire connecting a semiconductor chip to an inner lead, and the like from external air and mechanical shock such as humidity. I have.

One of the typical packages is resin sealing. This is because after setting the lead frame to which the connection of the semiconductor chip, etc. has been completed, it is set in a heated mold, pressure is applied to the softened resin, injected into the mold, molded, cooled after molding, and cooled. Is to be cured. In order to prevent the resin injected in such a resin sealing step from leaking between the leads, a tie bar connecting the leads is formed on the lead frame.
Therefore, it is necessary to cut the tie bar and separate the lead after cutting the resin and before cutting and forming the lead.

Hereinafter, a conventional method for manufacturing a semiconductor device for cutting a tie bar will be described. A lead frame having a plurality of resin-encapsulated semiconductor devices to which leads are connected by tie bars is transported to tie bar cutting means for cutting the tie bars by the transport means. Then, the tie bar of the resin-encapsulated semiconductor device is cut by moving the cutting die having a predetermined shape downward while holding the lead from above and below. Is stored in

[0005]

The above-mentioned tie-bar cutting means cuts all tie-bars irrespective of whether the molding envelope (resin) of the resin-encapsulated semiconductor device is good or bad.
Further, at the time of cutting, the lead is pressed with a slight slack so that no pressure mark remains on the lead regardless of the presence or absence of burrs. Therefore, the following problem occurs.

For example, it is assumed that, in a QFP (Quad Flat Package), a resin is not completely filled in a mold at the time of resin sealing, and a desired shape cannot be obtained. FIG. 5 is a schematic plan view showing a resin sealing imperfect part 2 ', that is, a QFP having an unfilled resin part.

In this state, when a load is applied to the tie bar by the cutting die, the load is applied to the resin from the inner leads. The incompletely resin-sealed portion 2 ′ shown in FIG. 5, that is, the unfilled resin portion has a lower strength than other portions, and therefore cannot receive the load from the tie-bar cutting die. The resin around the 'is cracked, and in some cases, the resin is scattered, and fragments thereof remain in the cutting mold.

[0008] Also, when resin is present in the resin, when a load is applied to the tie bar by the cutting die, the resin is weaker than the resin-encapsulated semiconductor device in a good state, so that cracks occur and the worst case occurs. In this case, the resin is scattered, and fragments thereof remain in the cutting mold.

When the tie bar of the next resin-encapsulated semiconductor device is cut in such a state, not only a defect in the cut state occurs but also the cutting die itself is damaged. In particular, with the miniaturization of semiconductor devices, the cutting of tie bars having leads whose pitch is becoming narrower requires a thin cutting die, and even small resin fragments are easily damaged by serious problems. Had become. Therefore, the present invention
It is an object of the present invention to provide a semiconductor manufacturing apparatus and a semiconductor manufacturing method that solves the above-described problem and that cuts only a tie bar relating to a good resin-sealed semiconductor device and protects a cutting die without cutting the other tie bars. .

[0010]

In order to achieve the above object, an apparatus for manufacturing a semiconductor device according to the present invention comprises a semiconductor device and a shape of an envelope which covers a part of a lead connected to an electrode of the semiconductor device. Inspection means for inspecting a state in which a tie bar connecting a lead near the envelope exists, comparing the inspection data with reference data, and when the result is within an allowable range, judging a good state; Only a semiconductor device having an envelope determined to be in a state has tie bar cutting means for cutting a tie bar between leads.

It is to be noted that the semiconductor device has marking means for marking the envelope when the envelope is in a defective state, and that the inspection means is in a good state when there is no mark on the envelope. It is characterized by determining.

Further, the semiconductor device manufacturing apparatus of the present invention comprises:
A guide rail on which a semiconductor device in a state where a tie bar connecting a lead exists near an envelope surrounding a part of a lead connected to a semiconductor element and an electrode of the semiconductor element;
The semiconductor device on the guide rail is transported from one side to the other, and the envelope of the semiconductor device on the guide rail is inspected, and the inspection data is compared with the reference data. Inspection means for judging a good state when in an allowable range, and cutting a tie bar between leads only in a semiconductor device having an envelope judged to be in a good state;
And a tie bar cutting means provided on the transport direction side of the inspection means.

[0013] The inspection means has an optical sensor as means for inspecting the shape of the envelope of the semiconductor device. The semiconductor device is a resin-sealed semiconductor device.

Further, a method of manufacturing a semiconductor device according to the present invention
Inspecting the shape of the envelope covering a part of the lead connected to the semiconductor element and the electrode of the semiconductor element while a tie bar connecting the lead is present in the vicinity of the envelope; and Comparing the data, and when the comparison result is within an allowable range, determining a good state,
Cutting only the tie bars between the leads only in the semiconductor device having the envelope determined to be in a good state.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor manufacturing apparatus and a semiconductor manufacturing system according to the present invention will be described below with reference to the drawings. FIG.
1 is a schematic front view showing the entire semiconductor manufacturing apparatus of the present invention. FIG. 2 is an enlarged schematic perspective view of a main part according to the first embodiment of the present invention. In FIG. 1, marks are provided on the guide rails 3 at predetermined intervals for reference of the distance.

The lead frame 1 has a plurality of resin-sealed semiconductor devices 2 to which leads 1b are connected by tie bars 1a. The lead frame 1 is transported on the guide rail 3 to tie bar cutting means 4u and 4d for cutting the tie bar 1a by a transport means (not shown). At this time, as shown in FIG. 2, the detecting means (the optical sensor 5a in this embodiment) on the transporting means detects the presence or absence of the mark 6 attached to the resin-encapsulated semiconductor device 2.

The mark 6 is provided in advance to identify whether or not the resin is good when inspecting the resin state after resin sealing. Here, a mark is attached to the defective product.

The tie bar cutting means 4 receives the detection result of the sensor 5a and cuts only the tie bar 1a of the resin-sealed semiconductor device 2 in a good resin state. Do not disconnect.

Specifically, when cutting the tie bar 1a, the resin-sealed semiconductor device 2 is set at a predetermined position on the cutting die lower part 4d, and the transport means is temporarily stopped. Next, the stripper and the punch of the cutting die upper part 4u composed of the stripper for holding the lead and the punch for cutting the tie bar 1a are lowered.

The stripper and cutting die lower part 4d is a comb having substantially the same interval as the lead 1b, and is provided so as to sandwich only the lead 1b from above and below after the stripper is lowered. In addition, the punch is a comb type inverted from the stripper. Therefore, by lowering the punch after lowering the stripper to pinch the lead 1b from above and below, the punch comes into contact with the tie bar 1a, and the tie bar 1a is finally cut off.

Subsequently, the cutting mold upper part 4u (stripper and punch) is raised, and the conveying means is moved to convey the cut resin-encapsulated semiconductor device 2, and the next resin-encapsulated semiconductor device 2 is moved. Install.

On the other hand, when the cutting of the tie bar 1a is not performed, the cutting die upper part 4u is not moved up and down, but is conveyed by the conveying means to perform an appropriate treatment. In addition, the movable of the conveyance means
It is an intermittent type that performs a temporary stop when the tie bar is cut. When the primary stop time is excluded, regardless of whether the tie bar is cut or not, the time from when the resin-sealed semiconductor device 2 comes to the next position comes to the predetermined position of the cutting die lower part 4d. It takes about one second. During this time, the detection by the sensor 5a can be terminated, so the tie bar cutting means
4, the flow speed of the resin-encapsulated semiconductor device 2 is kept substantially constant. That is, it is not necessary to temporarily stop the tie bar cutting means 4 and the like only for detection.

Therefore, according to this embodiment, only the tie bar 1a of the resin-sealed semiconductor device 2 having a good resin state can be cut. For example, when the resin-encapsulated semiconductor device 2 in the good / defective state is mixed in one lead frame, there is an effect that only the resin-encapsulated semiconductor device 2 in the good state can be taken out. Also, when there is a defective resin-encapsulated semiconductor device 2, particularly when it is continuously present, the vertical movement of the cutting mold upper part 4u for cutting the tie bar 1a becomes unnecessary, so that the next The resin-sealed semiconductor device 2 can be started. Further, breakage of the cutting die due to cutting of the tie bar 1a of the resin-sealed semiconductor device 2 in a defective state can be prevented.

Therefore, according to the present invention, the quality of the finally obtained resin-encapsulated semiconductor device 2 can be highly compensated, and the device for cutting the tie bar 1a can be prevented from being damaged.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a perspective view of a main part of a semiconductor manufacturing apparatus according to a second embodiment of the present invention. The description of the parts common to the first embodiment is omitted.

The difference from the first embodiment is that the detection means 5 uses a camera 5b. The camera 5b observes the appearance of the resin-encapsulated semiconductor device 2 and compares the observed data with standard data, thereby obtaining the resin-encapsulated semiconductor device 2.
Is good or bad.

The tie bar cutting means 4 receives the result,
Tie bar 1a of resin-encapsulated semiconductor device 2 having good resin state
Only the tie bar 1a of the resin-encapsulated semiconductor device 2 is not cut. Specific means and the like are the same as in the first embodiment.

In the second embodiment, it takes more time to judge the quality of the resin than in the first embodiment. However, the resin-sealed semiconductor device 2 is moved to a predetermined position of the cutting die lower part 4d. Since the process can be almost completed during the time from when the next one comes until the next one comes, the flow speed of the resin-encapsulated semiconductor device 2 with respect to the tie bar cutting means 4 is kept substantially constant, and the tie bar cutting means 4 and the like are temporarily stopped. No need.

In the second embodiment, there is a merit that the marking for identifying the inspection result of the resin state is not required before this step. Further, since the present invention can be applied to the resin-sealed semiconductor device 2 having no marking, it is highly versatile. In addition, if a defect occurs in the state of the resin-encapsulated semiconductor device immediately before cutting the tie bar 1a, it can be detected, thereby improving the yield of the finally obtained resin-encapsulated semiconductor device 2. can do.

As described above, according to the present embodiment, similarly to the first embodiment, the resin-sealed semiconductor device 2 having a good resin state is provided.
Can cut only the tie bar 1a. Therefore, when the resin-encapsulated semiconductor device 2 in a good / defective state is mixed in one lead frame, there is an effect that only the resin-encapsulated semiconductor device 2 in a good state can be taken out. Further, when the resin-encapsulated semiconductor device 2 in a defective state exists, particularly when it is continuously present,
Since the vertical movement of the cutting mold upper part 4u for cutting the tie bar 1a is not required, the next resin-encapsulated semiconductor device is faster than before.
You can work on 2. Further, breakage of the cutting die due to cutting of the tie bar 1a of the resin-sealed semiconductor device 2 in a defective state can be prevented.

Therefore, according to the present invention, the quality of the resin-encapsulated semiconductor device 2 finally obtained can be highly compensated, and the device for cutting the tie bar 1a can be prevented from being damaged.

The present invention is not limited to the above embodiment, but can be modified as follows. As the detection means 5,
Means for irradiating the resin-encapsulated semiconductor device 2 with light and observing the degree of reflection can be used. In this case, the quality of the resin-encapsulated semiconductor device is determined by comparing the observed data with the standard data as in the case of the camera 5b. Although this method has a disadvantage that detection requires time, it has an advantage that the state can be measured at a high level.

Further, the detecting means 5 may have a function of judging whether the state of the lead frame or the like other than the resin state is good. In this case, although a long time is required for the determination, the quality of the finally obtained resin-encapsulated semiconductor device 2 can be improved.

In the above embodiment, the detection means 5
Although it is located on the guide rail 3 before being conveyed to the tie bar cutting means 4, the position is not particularly limited as long as the state of the resin-encapsulated semiconductor device 2 can be observed. For example, as shown in FIG.
The detecting means 5 may be provided in the tie bar cutting means 4. In particular, it is preferable that the detection means 5 is installed at a position where the resin-sealed semiconductor device 2 is observed just before cutting the tie bar 1a, since the latest state of the resin-sealed semiconductor device 2 can be detected.

When the tie bar cutting means 4 cuts the tie bars 1a of a plurality of resin-encapsulated semiconductor devices 2 at a time (the number to be cut is one set), the judgment result by the detecting means 5 is determined. This can be handled by storing the data in one set out of order.

Further, the present invention can be applied to a case where a laser beam is used as the tie bar cutting means 4. In this case, there is an advantage that the running cost can be reduced because the resin-encapsulated semiconductor device 2 in the defective state is not cut as in the above embodiment.

[0037]

According to the present invention, the quality of the finally obtained resin-encapsulated semiconductor device 2 can be highly compensated, and the device for cutting the tie bar can be prevented from being damaged.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a semiconductor manufacturing apparatus according to the present invention.

FIG. 2 is an enlarged schematic perspective view of a main part according to the first embodiment of the present invention.

FIG. 3 is an enlarged schematic perspective view of a main part according to a second embodiment of the present invention.

FIG. 4 is a schematic perspective view of a semiconductor device according to an application example of the present invention.

FIG. 5 is a plan view for explaining a conventional example, showing a lead frame in which good / defective resin sealing devices are mixed.

[Explanation of symbols]

 1 Lead frame 1a Tie bar 1b Lead 2 Resin-sealed semiconductor device 3 Guide rail 4 Tie bar cutting means 4u Cutting die upper part 4d Cutting die lower part 5 Detecting means 5a Optical sensor 5b Camera 6 mark

Claims (6)

[Claims] An inspection of a shape of an envelope covering a part of a lead connected to a semiconductor element and an electrode of the semiconductor element is performed in a state where a tie bar connecting the lead exists near the enclosure. Inspection means for comparing the data with the reference data and determining if the result is within an allowable range, and a tie bar cutting for cutting a tie bar between leads only in a semiconductor device having an envelope determined to be in a good state. And a means for manufacturing a semiconductor device. 2. The semiconductor device according to claim 1, further comprising a marking unit for marking the envelope when the envelope of the semiconductor device is in a defective state. The apparatus for manufacturing a semiconductor device according to claim 1, wherein the determination is performed. 3. A guide rail on which a semiconductor device having a tie bar connecting a lead near an envelope covering a part of a lead connected to a semiconductor element and an electrode of the semiconductor element is provided; Transport means for transporting the semiconductor device from one side to the other on a rail, and inspecting an envelope of the semiconductor device on the guide rail, comparing the inspection data with reference data, and determining that the result is within an allowable range. At one time, inspection means for judging a good state and tie bar cutting means provided on the transport direction side of the inspection means for cutting a tie bar between leads only in a semiconductor device having an envelope judged to be in a good state A semiconductor manufacturing apparatus comprising: 4. The semiconductor manufacturing apparatus according to claim 1, wherein said inspection means has an optical sensor as means for inspecting a shape of an envelope of said semiconductor device. 5. The semiconductor manufacturing apparatus according to claim 1, wherein said semiconductor device is a resin-encapsulated semiconductor device. 6. A step of inspecting the shape of the envelope covering a part of the lead connected to the semiconductor element and the electrode of the semiconductor element while a tie bar connecting the lead exists near the envelope. A step of comparing the inspection data with the reference data; a step of determining a good state when the comparison result is within an allowable range; and a step of determining a tie bar between leads only for a semiconductor device having an envelope determined to be in a good state. Cutting the semiconductor device.