JPH0769159B2 - Inspection equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection device for inspecting a bend or a lift of a lead or the like located on a side surface or a lower surface of a semiconductor device or the like.

[Prior Art] An example of a conventional inspection apparatus will be described with reference to FIG.

An inspection table 23 is provided at the center of the support table 21, on which an inspected object 22 made of a semiconductor device or the like having leads 20 on its side surface is placed. On both outsides of the inspection table 23, an image reflection plate 24 for projecting the side surface of the inspection object 22 and the leads 20 is integrally provided on a holding table 25, and is rotatably supported by a locking pin 26 of the supporting table 21. Installed in part. Also, above the image reflector 24,
A lamp 27 is arranged together with a cover 28 adapted to irradiate the object 22 with the irradiation light. Further, the inspection object 22
An image pickup device 29 such as a CCD camera for picking up an image of the side surface of the object 22 to be inspected and the lead 20 reflected by the image reflection plate 24 is provided above.

In such a structure, the side surface of the inspection object 22 and the leads 20 are irradiated with the light of the lamp 27, and the imaging device 29 provided above the inspection object 22 by the image reflector 24 whose position is adjusted.
Then, the image of the leads 20 is displayed on a monitor (not shown) and the leads 20 are inspected for bending, rising, and missing.

[Problems to be Solved by the Invention]

However, with the above structure, when the lead of the DUT is bent inward, the irradiation light from the lamp does not form a uniform image due to the curvature of the surface of the lead, so However, there is a problem in that the vicinity of the contact surface of the lead of the inspected object becomes a dark portion and is directly displayed on the monitor, so that it is impossible to accurately inspect / determine a defect such as a fine lead floating. In addition, since light is emitted from a lamp arranged outside the inspection object, unnecessary light around the inspection object placed on the inspection table is also irradiated, and extra light is diffusely reflected. However, this also has a problem that the defect cannot be accurately inspected and judged.

The object of the present invention is to prevent light from irradiating an unnecessary portion without producing a dark portion in the vicinity of the contact surface between the lead or the like and the inspection table even when the lead or the like is bent inward. Accurate inspection by eliminating the occurrence of diffuse reflection
An object of the present invention is to provide an inspection device capable of making a determination.

[Means for Solving the Problems]

The inspection apparatus of the present invention includes an inspection table provided with an image reflection plate on which an object to be inspected is mounted, a light source arranged below the image reflection plate on the inspection table, and an object to be covered by the image reflection plate. Irradiation that penetrates a part of the region where the inspection object is placed and is provided so as to project from the image reflection plate, and irradiates light from the light source to the contact surface portion between the inspection object and the image reflection plate. And an image pickup device arranged at a position facing the irradiation unit with a contact surface portion between the object to be inspected and the image reflection plate sandwiched therebetween.

[Action]

With the configuration of the present invention, the irradiation light is emitted not directly from the outside of the inspection object but directly below the inspection object, that is, below the inside of the inspection object region, so that the inspection object has a curved surface. Accurate images can be obtained without causing dark areas due to curved surfaces at the contact surface between the object to be inspected and the image reflector, and unnecessary light is not emitted from the outside, so irregular reflection is eliminated. It is possible to prevent the occurrence of noise and obtain an accurate image. In addition, since the real image of the shadow and the reflection image reflected on the image reflection plate can be simultaneously imaged at the contact surface portion, it is possible to perform accurate inspection / judgment, particularly with respect to minute bending and rising of the lead of the inspection object. it can.

〔Example〕

An embodiment of the inspection apparatus of the present invention will be described based on FIGS. 1 and 2.

As shown in FIG. 1, this inspection apparatus has an image with a low distortion rate in which an object to be inspected 2 of a semiconductor device having leads 3 is placed and the lower side surface 2a of the object to be inspected 2 and the leads 3 are projected from the back surface. The reflection plate 4 is provided on the upper surface of the inspection table 1. A positioning portion 5 for restricting the position of the object 2 to be inspected to be mounted is provided around the base 5a with a gap from the upper surface of the inspection table 1. Further, inside the inspection table 1, a lamp 7 as a light source, which is a high-frequency lighting fluorescent lamp that emits light, and an inspection table 1 are provided.
An illuminating device 8 is provided, which includes an illuminating section 6 that is located below the DUT 2 and that penetrates part of the image reflecting plate 4. The irradiation unit 6 is made of ground glass or a polymer material that transmits and scatters the irradiation light of the lamp 7.
It is possible to irradiate the area between the inspection object 2 and the transmitted scattered light.

Further, from the gap between the inspection table 1 and the positioning part 5, the image of the lower side surface 2a of the inspected object 2 and the lead 3 and its reflection image are picked up and reflected on the monitor (not shown) so as to be projected on a monitor (not shown). An image pickup device 9 composed of a CCD camera is provided at a position facing the irradiation unit 6 with a surface contacting with the plate 4 interposed therebetween.
It should be noted that this imaging device 9 may be installed in four units so that the lower side surface 2a of the four sides of the inspection object 2 and the leads 3 can be imaged at one time, or one unit or two units are installed and four or two positions are moved. Alternatively, the four lower side surfaces 2a and the leads 3 of the inspection object 2 may be imaged.

In the above structure, the light emitted from the lamp 7 is transmitted and scattered by the irradiation unit 6 and is emitted from the back surfaces of the DUT 2 and the leads 3. As shown in FIG. 2, the transmitted and scattered irradiation light produces a real image 10 of a shadow formed by the lower surface 2a of the inspection object 2 and the leads 3. Further, the real image 10 of the shadow is reflected on the image reflecting plate 4, and the virtual image 11 of the shadow by the lower side surface 2a of the inspection object 2 and the lead 3 is also produced at the same time. Then, the real image 10 and the reflected image 11 of the shadow of the lower surface 2a of the inspection object 2 and the leads 3 are picked up by the image pickup device 9 and displayed on the monitor, and the state of the leads 3 is passed as compared with the regular inspection object. A pass / fail judgment is made by inspecting whether or not it is within an allowable range.

2 (a) to 2 (d), the lower surface 2a and the lead 3 of the device under test 2 imaged by the imaging device 9 and displayed on the monitor.
An example of the real image 10 and the reflected image 11 of the shadow by will be described.

FIG. 2 (a) is a shadow real image 10 and a reflection image 11 showing a normal state without bending or lifting of the lead, and FIG. 2 (b).
Is a real image 10 and a reflection image 11 of a shadow showing a defective product in which one of the leads is bent laterally (section A), and FIG. 2 (c) shows that one of the leads is bent too much and other leads 3 Real image 10 and reflected image 1 of the shadow showing the defective product in the raised state (part B)
1 and FIG. 2 (d) are a shadow real image 10 and a reflection image 11 showing a defective product in a state where one of the leads has little bending and the other lead is lifted (C portion).

In this way, the imaging device 9 that images the lower surface 2a of the inspection object 2 and the leads 3 can image the lower surface 2a of the inspection object 2 and the leads 3 as shadows. Since the irradiation light is emitted not directly from the outside of the inspection object 2 but directly below the inspection object 2, that is, below the inside of the inspection object region, the inspection object 2 has the lead 3 bent inward. However, a dark image does not occur at the contact surface between the lead 3 and the image reflection plate 4, an accurate image can be obtained, and light is not emitted from the outside, so unnecessary portions are illuminated. It is possible to prevent the occurrence of irregular reflection, obtain an accurate image, and perform accurate inspection / judgment. Further, the real image 10 of the shadow by the lower surface 2a of the object 2 to be inspected and the leads 3 and the reflection image 11 of the real image 10 of the shadow reflected on the image reflection plate 4 can be simultaneously picked up and inspected, and the lead 3 is lifted up. With respect to a defect, it is possible to make a pass / fail determination with about twice the accuracy.

〔The invention's effect〕

The inspection apparatus according to the present invention includes an inspection table provided with an image reflection plate on which an inspection object is placed, a light source arranged below the image reflection plate on the inspection table, and an inspection object of the image reflection plate. An irradiation unit that penetrates a part of the area to be placed and is projected from the image reflection plate, and irradiates light from the light source to the contact surface portion between the inspection object and the image reflection plate, and the inspection object. Since the imaging device is provided at a position facing the irradiation unit with the surface contacting with the image reflection plate interposed therebetween, the irradiation light does not come from outside the inspection object but directly below the inspection object, that is, the inspection object. Since the light is emitted from below the inside of the body region, an accurate image can be obtained without causing a dark portion due to the curved surface at the contact surface portion between the inspection object and the image reflection plate even if the inspection object has a curved surface. Also, since no light is radiated from the outside, unnecessary spots are not illuminated and diffuse reflection is generated. To prevent, correct image is obtained,
Accurate inspection / judgment can be performed. In addition, since the real image of the shadow and the reflection image reflected on the image reflection plate can be simultaneously captured at the contact surface portion, it is possible to accurately inspect / determine particularly the minute bending and rising of the lead of the inspection object. it can.

[Brief description of drawings]

FIG. 1 (a) is a plan view of an embodiment of the inspection apparatus of the present invention, FIG. 1 (b) is a side sectional view thereof, and FIGS. 2 (a) to (d) are imaging views obtained by the same. FIG. 3 is a side view of a conventional inspection device. 4 ... Image reflector, 6 ... Irradiation part, 7 ... Lamp, 8 ...
... Illumination device, 9 ... Imaging device, 10 ... Real image, 11 ... Reflected image

Claims (1)

[Claims] 1. An inspection table provided with an image reflecting plate on which an object to be inspected is mounted, a light source arranged below the image reflecting plate on the inspection table, and an object to be inspected of the image reflecting plate. An irradiating unit that penetrates a part of the area where the slab is placed, is provided so as to project from the image reflection plate, and irradiates light from the light source to a contact surface portion between the inspection object and the image reflection plate. An inspection apparatus, comprising: an imaging device disposed at a position facing the irradiation unit with a contact surface portion between the inspection object and the image reflection plate being sandwiched therebetween.