JPH06112387A - Cutting inspection method of lead holding member for semiconductor element - Google Patents

Abstract

PURPOSE:To detect any abnormal cutting work immediately after the occurrence of the same for avoiding the feed of the defective work to later steps by inserting a block member into holding members for photoelectrically detecting any mechanical displacement. CONSTITUTION:A lead frame 1 after finishing the cutting off step of holding members is carried by a rail 11 to the position right above a block member 5. At this time, the rail 11 actuates the block member 5 downward to be inserted into the holding members. When the holding members are not cut off due to broken punch 9 or die 10, any remaining holding members mechanically press down the block member 5 by the force of the first spring 12 lowering the rail 11. When the block member 5 is pressed downward, a protruding pin 15 lowered to press down a plate 18 thereby lowering a sensor plate 21. Accordingly, a hole passing the irradiating light from a transmission type sensor 22 is shifted downward to shield the irradiating light. Resultantly, any abnormal cutting work of the holding members can be detected thereby enabling the operation of a cutting device to be stopped by the detection signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting inspection method for a lead supporting material for semiconductor devices, and is particularly suitable for a cutting die and a cutting device corresponding thereto.

[0002]

2. Description of the Related Art Recent semiconductor elements tend to have a higher degree of integration with the progress of fine processing technology, and the assembling technology corresponding thereto has been greatly improved. Therefore 200
A multi-pin device having more than pins is commercially available, and in addition to the so-called tab system, a system using a lead frame is also adopted in preparation for this. A lead frame for a multi-pin element tends to have a smaller thickness in addition to a smaller pitch in order to increase the number of leads, and is often formed by an etching process rather than a pressing process. Such a lead frame
There are known types of SIP, DIP, QFP, SOP, etc., but all of them are provided with a so-called tie bar or support material to maintain mechanical strength and a so-called resin after mounting a semiconductor element. The outer lead connected to the outside of the sealing resin layer in the sealing step is connected. After the resin sealing step, the support material is mechanically cut and removed. Outer
Since the leads are electrically connected to external electronic devices, the leads are more common in multi-pin devices or microfabricated semiconductor devices.

A reel mounted with a semiconductor element in this manner
The dframe protects the semiconductor element from the outside atmosphere by cutting and removing the support material after sealing the resin by the transfer mold method.

In the cutting and removal of the support material, it is the current situation that the operator visually checks to see whether or not a normal work has been performed, that is, whether all the support materials have been cut. This process is performed by a cutting punch or die, but if the cutting debris becomes clogged, it will break.

[0005]

Since the cutting and removing process of the tie bar depends on the visual inspection of the operator, it is not carried out for all the semiconductor elements to be processed but is carried out at a certain ratio, and there is an abnormality. You need to look at all that has already been processed.

For this reason, the production efficiency is low, and mistakes are likely to occur in confirmation. Furthermore, if the confirmation is made at a certain ratio, a semiconductor element having abnormal cutting is frequently produced, and mistakes are likely to occur in the confirmation. Furthermore, if no confirmation is made at all, until a worker or another person notices the cutting abnormality, the semiconductor element having the cutting abnormality is continuously produced, and may be supplied to the subsequent steps.

The present invention has been made under such circumstances, and an object of the present invention is to provide a novel lead frame tie-bar disconnection inspection method for semiconductor devices.

[0008]

A semiconductor element to be processed, which has undergone the cutting step, is placed in a mold when cutting a supporting material for connecting a lead led out from a sealing resin layer covering the semiconductor element to the outside. And a step of inserting a block material between the leads, a step of pushing down the block material due to the presence of the support material, and a cutting device arranged corresponding to the mold. A step of vertically moving the attached sensor plate, a step of irradiating a shaft moving integrally with the sensor plate with light, and a step of photoelectrically converting a displacement amount of the shaft moving in the irradiation light. Further, there is a feature of the cutting inspection method for the lead supporting material for semiconductor devices according to the present invention.

[0009]

In the lead frame formed by various sizes, the supporting materials also have different sizes, so that a mold corresponding to each is required. However, in the present invention, the block material is inserted between the support materials, and the method of photoelectrically detecting the mechanical displacement due to the presence or absence of the support material is adopted, so that it is possible to support the models having different sizes.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described with reference to FIG. 1 showing a perspective view of a block material used in the present invention and FIG. 2 showing a cross section of one embodiment.

A semiconductor element (not shown) mounted on the lead frame 1 is subjected to a resin encapsulation process, and a support member 4 for connecting the outer lead 3 led out of the resin layer 2 is present. FIG. 1 shows a block member 5 that moves downwards by moving. As is apparent from this figure, the block member 5 is provided with the projecting portions 6 at a constant pitch a, and the supporting member 4 connecting the outer lead 3 is brought into contact with the concave portion b between them.

For this purpose, the mold 7 and the corresponding cutting device 8 shown in FIG. 2 are used. The die 7 includes a die 9 for cutting the support material 4 and a punch 1.
0, and a rail 11 for mounting the semiconductor element and carrying the lead frame 1 which has completed the resin sealing step.
Install. The rail 11 can move up and down, and the first spring 12 is installed so as to move down. Furthermore,
The block member 5 inserted between the outer leads 3 is also vertically movable, and the guide rod 13 is installed on the block member 5. Furthermore, in order to smooth the vertical movement of the block member 5, the linear bushing 14 is attached. Block material 5
The protrusion pin 15 for transmitting the positional displacement of the second spring 16 and the second spring 16 for maintaining the initial position thereof are set in the mold 7. The cutting device 8 arranged corresponding to the mold 7 is provided with a vertically movable plate 18 for receiving the position change of the projecting pin 15, and a linear shaft 19 is attached to the plate 18. This is a bearing mechanism for reducing sliding resistance.

In addition, a third spring 20 for holding the plate 18 in the initial position is also installed in the cutting device 8.

At the lower end of the linear shaft 19, a sensor plate 21 having a hole through which light from a sensor, which will be described later, which is the most important for the present invention, is installed. This sensor
At the position corresponding to the plate 21, a transmissive sensor-22
The sensor at the initial position of the plate 18
The holes of the plate 21 are positioned so that the light from the transmissive sensor 22 can be irradiated.

In the die 7 and the cutting device 8 as described above, the outer reel is provided outside the sealing resin layer 2 after the cutting process of the support member 4 is completed.
The lead frame 1 provided with the cord 3 is conveyed right above the block material 5 by the rail 11. At that time, the rail 11 works downward, and the block member 5 is relatively inserted into the support member 4 between the outer leads 3.

Punch 9 or die 1 for cutting the support 4
When the support member 4 is not cut due to damage to the block 0, the remaining support member 4 mechanically pushes down the block member 5 by the force of the first spring 12 that moves the rail 11 downward. . When the block material 5 moves downward, the protruding pin 15
Lowers to push down the plate 18, and the sensor plate 21 also lowers accordingly.

Therefore, the hole for passing the irradiation light from the transmission type sensor 22 also moves downward, so that the irradiation light is blocked. As a result, a cutting abnormality of the support material 4 is detected, and the operation of the cutting device 8 is stopped based on the signal.

If the support member 4 is cut normally, it does not come into contact with the block member 5, so that the block member 5 does not descend even if the rail 11 moves downward. Then, the rail 11 is raised and the lead frame 1 provided with the outer lead 3 is conveyed outside the sealing resin layer 2. This process is sequentially repeated to inspect all semiconductor devices that have completed cutting of the support material 4.

Since the presence / absence of the supporting material can be automatically confirmed in this manner, the manual operation can be eliminated and the abnormal operation due to the existence of the supporting material can be detected immediately after the occurrence of the abnormal semiconductor element in the subsequent steps. Never turn it.

[0020]

EFFECTS OF THE INVENTION Since the support material cutting confirmation work is not performed manually and can be detected immediately after the occurrence of an abnormality,
It is possible to prevent supply of an abnormal work in the subsequent process.

[Brief description of drawings]

FIG. 1 is a perspective view showing a relationship between a block material used in the present invention and a lead frame provided with an outer lead outside a sealing resin layer.

FIG. 2 is a diagram showing a cross section of one embodiment according to the present invention.

[Explanation of symbols]

 1: lead frame, 2: sealing resin, 3: outer lead, 4: support material, 5: block material, 6: projecting portion, 7: mold, 8: cutting device, 9: die , 10: punch, 11: rail, 12, 16, 20: spring, 13: guide rod, 14: linear bush, 15: protruding pin, 17: set screw, 18: plate, 19: linear shaft, 21: sensor-plate, 22: transmissive sensor-.

Claims (1)

[Claims] 1. A step of arranging a semiconductor element to be processed, which has undergone the cutting step, in a mold when cutting a supporting material for connecting a lead led out from a sealing resin layer covering the semiconductor element to the outside, A step of inserting a block material between the leads, a step of pushing down the block material due to the presence of the support material, and a sensor plate attached to a cutting device arranged corresponding to the mold by this step. -Moving the grate vertically,
A semiconductor device reel comprising: a step of irradiating a shaft moving integrally with the sensor plate with light; and a step of photoelectrically converting a displacement amount of the shaft moving in the irradiation light. Inspection method for cutting support material