JPH04100830U - Gate resin remaining detection device - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for detecting the state of remaining gate resin of a resin molded product, for example, a resin molded semiconductor device.

[Prior Art] When a transfer molded resin mold type semiconductor device is resin-molded, when the upper and lower molds are opened and taken out, as shown in FIG. The resin 4 of the runner portion hardened in the resin flow path connected to the gate resin 3 is taken out as one piece.

The diameter of the gate resin 3 is reduced from the runner toward the exterior part 2 of the semiconductor device 1, and the cross-sectional area of the runner part connected to the resin 4 is maximum. Both the gate resin 3 and the runner resin 4 are unnecessary. Therefore, in the next step, the lead frame 5 to which the semiconductor device 1 is connected and the resin 4 of the runner part are supported respectively, and the end face 2 of the semiconductor device 1 is the base point in the figure, and the resin 4 of the runner part is supported in the downward direction. , a force is applied upwardly to each lead frame 5, and each gate resin 3 is broken off so that a folded end surface of the gate resin 3 is formed on the end surface 2 of the semiconductor device 1.

However, the above-mentioned gate resin 3 is not used in the semiconductor device 1.
The work of breaking off from the end face 2 of is generally performed manually by an operator. Therefore, depending on the skill level of the operator, it may not be possible to completely remove the gate resin 3, and as shown in FIG. It was possible to form.

In this way, if the remaining gate resin 7 protrudes from the end surface 2 of the semiconductor device 1, when the individual semiconductor devices 1 are separated from the lead frame 5 and used as a product, not only will the appearance deteriorate, but also the semiconductor device When mounting on a printed circuit board using a feeder, etc., the remaining gate resin 7 may cause errors in dimensions, etc., making accurate positioning impossible, or when mounting on a printed circuit board, etc., which requires space saving, the remaining gate resin 7 may There are various problems such as other components mounted in close proximity to each other coming into contact with each other, making it impossible to mount them. Therefore, it was necessary to reliably detect a semiconductor device in which the remaining gate resin 7 protrudes.

[Problem to be solved by the invention] However, as a method for detecting the remaining gate resin 7, generally, the end surface 2 of the semiconductor device 1 is shown with a television camera or the like to visually recognize the remaining gate resin 7, or the remaining gate resin 7 is detected by direct visual inspection. Resin remaining 7
Tests to find out were common. Therefore, when inspected visually, the folded end surface 6 of the remaining gate resin 7 and the end surface 2 of the semiconductor device 1 are of the same color, making it difficult to obtain a contrast, resulting in the problem that the remaining gate resin 7 is easily overlooked. Further, even if a television camera or the like is used, the number of semiconductor devices 1 produced is extremely large, so it is easy to overlook semiconductor devices with gate resin residue.

[Means for Solving the Problems] In order to achieve the above problems, the gate resin remaining detection device of the present invention detects the gate portion of a resin molded product obtained by injecting resin into a mold cavity through a gate. A gate resin remaining detection device for detecting resin remaining in the resin molding, the device comprising: a light source that irradiates light onto an end face of the gate resin of the resin molding; a television camera that images the end face; and an image signal from the television camera that receives a predetermined image signal. The present invention is characterized by comprising a comparison/determination unit that compares the signal pattern and determines whether it is good or bad.

[Function] In the gate remaining detection device having the above configuration, when light is irradiated from the light source to the gate resin end face of the resin molded product and the end face is imaged with a television camera, the folded end face where the gate resin is broken off becomes an uneven and rough surface. Therefore, the light irradiated on the folded end face is diffusely reflected, and the end face of the resin molded product appears bright on the TV camera, while the actual folded end face of the gate resin appears darker than its surroundings. In this case, the gate resin becomes thicker as it goes away from the end face of the resin molding, so the folded end face of the regular gate resin that is broken along the end face is displayed dimly in its narrowest state, and this image is used as the reference. If this is the case, the actual folded end surface when there is gate resin residue will be projected wider than the folded end surface of the above-mentioned regular gate resin. Therefore, in the comparison quality determination section, for example, the image of the actual folded edge surface that is displayed dimly is subjected to image processing, etc., the imaging area of the folded edge surface is calculated, and the area of the folded edge surface with the remaining regular gate resin calculated in advance is calculated. When compared with the imaging area, if the imaging area is large, it can be determined that the remaining gate resin exists protruding from the end surface of the semiconductor device.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a gate resin remaining detection device according to an embodiment of the present invention. The resin molded object to be tested is, for example, a semiconductor device 1 such as a transfer-molded transistor, and since the semiconductor device 1 is substantially the same as that shown in the conventional example, The same members are given the same reference numerals, and a description of the semiconductor device 1 will be omitted here.

The device for detecting remaining gate resin of the present invention shown in the figure breaks off the gate resin, which changes in cross-sectional area as it moves away from the end surface 2 of the semiconductor device 1 after resin molding, by the method shown in the conventional example. This is a device for detecting whether or not the folded end surface 6 protrudes from the end surface 2 to form a gate resin residue 7. That is, the semiconductor device 1 to be tested is placed on a support plate 8 and sequentially moved, and a light source 10 that irradiates light onto the end surface 2 of the semiconductor device 1 and an image of the end surface of the semiconductor device 1 are used. The present invention is comprised of a television camera 20 that displays the image, and a comparison and determination section 30 that compares and determines the quality of the remaining gate resin.

The light source 10 is, for example, a high-intensity light bulb such as a halogen lamp, and is placed on the support plate 8 and irradiates light onto the end surface 2 of the semiconductor device 1 including the actual folded end surface 6 of the gate resin. It is. The light source 1
A half mirror 11 is provided in the middle of the optical path of 0, and the half mirror 11 can reflect and irradiate the light emitted from the light source 10 onto the semiconductor device 1.

The television camera 20 takes an image of the end face 2 of the semiconductor device 1 including the folded end face 6 obtained by breaking off the gate resin in a horizontal state from the side. The image is now displayed. The image of the end surface 2 of the semiconductor device 1 captured by the television camera 20 is an image of the substantial reflected light on the end surface 2 of the light irradiated from the light source 10 to the end surface 2 by the half mirror 11. Since most of the reflected light is captured by the television camera 20, the overall image appears relatively bright. In addition, the light irradiated on the folded end surface 6 obtained by breaking off the gate resin is diffusely reflected because the folded end surface 6 has an uneven rough surface, and the television camera 20 hardly captures the reflected light. The folded end surface 6 comes to be reflected in the bright end surface 2 in a dim state.

The comparison and determination section 30 includes the television camera 20
This section compares and determines the quality of the remaining gate resin 7 from the image of the end surface 2 of the semiconductor device 1 taken in the step 1, and is comprised of an arithmetic device such as a microcomputer. The comparison/discrimination section 30 performs image processing on the image of the actual folded end surface 6 of the gate resin, which is included in the bright end surface 2 of the semiconductor device 1 and appears dimly, captured by the television camera 20, and calculates, for example, its imaging area. S' is calculated and compared with the standard imaging area S to determine the difference.

Here, the reference imaging area S is calculated as follows. That is, since the gate resin is formed so as to become thicker as it goes away from the end surface 2 of the semiconductor device 1, the gate resin is formed on a regular folded end surface along the end surface 2 of the semiconductor device 1 without producing any remaining gate resin 7. When it is broken off, the cross-sectional area of the folded end surface becomes the minimum. Therefore, TV camera 2
When an image is taken in the same manner as described above at 0, a dim image of the folded end surface 6' is displayed in a small size as shown on the monitor 22. Since the cross-sectional area of the folded edge surface 6 that has generated the remaining gate resin 7 gradually increases, image processing is performed on the image of the regular folded edge surface 6' displayed on the monitor 22 to calculate the imaging area S, which is used as a reference value. do.

Therefore, in this comparison/discrimination section 30, the monitor 2
2 and is set in advance.
Compare the imaging area S' of ' and the imaging area S' of the actual folded end surface 6 displayed on the monitor 21, and if there is a difference between the two, that is, S'>S, the gate resin remains from the end surface 2 of the semiconductor device 1. 7 is determined to be protruding, and the semiconductor device 1 has gate resin remaining 7
can be detected as On the other hand, if S'=S with no difference between the two, it can be determined that the semiconductor device 1 has been broken off at the normal folding end surface 6' and that the remaining gate resin 7 is not formed.

In the gate resin remaining detection device having the above configuration, the end face including the actual folded edge surface 6 obtained by breaking off the gate resin of the semiconductor device 1 is imaged by the television camera 20, and the imaging area of the projected folded edge surface 6 is imaged in the comparison determination unit 30. S' is calculated and compared with the preset imaging area S of the folded end face 6' where no gate resin remains, and if there is even a slight difference between the two, it is determined that the folded end face 2 of the semiconductor device 1 is left unbroken. It can be determined that the remaining gate resin 7 is protruding, and the semiconductor device 1 including the remaining gate resin 7 can be mechanically and accurately detected. Therefore, the semiconductor device 1 having the remaining gate resin 7 can be accurately detected through mechanical comparison and determination of quality, and automation thereof can also be realized.

In the above embodiment, the end face including the folded end face of the gate resin of the semiconductor device 1 may be directly irradiated without using the half mirror 11, and the reflected light may be imaged by the television camera 20. In addition, the imaging center of the television camera 20 can be easily changed and adjusted by electrical control, so even if the type of semiconductor device changes, the imaging center can be appropriately changed or adjusted to make it easier to use over time. The imaging area of the end face 6 may be calculated by image processing or the like.

Further, the comparison and determination section 30 calculates the imaging area of the image of the actual folded end surface and compares it with a preset reference imaging area to determine the quality of the captured image of the actual folded end surface. The length of the diagonal line and one side of the image may be calculated by image processing, etc., and compared with the diagonal line and length of one side of a preset standard to determine the quality. Various methods can be used for the comparison and judgment method. It is.

The present invention is applicable not only to semiconductor devices but also to resin molded products in general.

[Effects of the Invention] As is clear from the above description, the remaining gate resin detection device of the present invention has the advantage of being able to mechanically compare and determine whether the remaining gate resin is good or bad and thereby reliably detect it.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing the outline of a gate resin remaining detection device according to an embodiment of the present invention, FIG. 2 is a partially cutaway perspective view showing a semiconductor device after resin molding, and FIG. FIG. 2 is a partially cutaway perspective view showing the semiconductor device in a folded state. 1...Resin molded product (semiconductor device), 2...End face, 3...Gate resin, 7...Remaining gate resin, 10
. . . Light source, 20 . . . Television camera, 30 . . . Comparison quality determination unit.

Correction: 3/19/1999
Correct the drawing as follows.

Claims (1)

[Scope of Claim for Utility Model Registration] A gate resin remaining detection device for detecting resin remaining at the gate portion of a resin molded product obtained by injecting resin into a mold cavity through a gate, which comprises: It is characterized by comprising a light source that irradiates light onto the end face of the gate resin of the molded product, a television camera that images the end face, and a comparison and determination unit that compares the image signal from the television camera with a predetermined signal pattern and determines the quality. gate resin remaining detection device.