JPH01302146A - Appearance inspecting device - Google Patents

Abstract

PURPOSE:To shield disturbing light accurately without causing a trouble in the transport of an object to be inspected, by moving a shielding plate to a disturbing light shielding position when an object to be inspected reaches an inspecting position to shift the shielding plate outside a moving locus of the object to be inspected after the end of picking up. CONSTITUTION:When a semiconductor device 1a reaches an inspecting position, a shielding plate 17 positioned at a rising position is lowered. Light from a light source other than a lighting device 19 is shielded. The semiconductor device 1a is irradiated with a light G photographable from the lighting device 19 synchronizing the shielding action and a bending of a lead is inspected by taking the semiconductor device 1a with a camera 12a. After a fixed time necessary for inspection of appearance passes, an output of the camera is cut off. The shielding plate 17 is lifted by an output of a control circuit synchronizing a timing of ending the photography and then, retracted outside a moving locus of the semiconductor device 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an appearance inspection apparatus for inspecting the appearance of semiconductor devices and the like.

BACKGROUND ART When inspecting a semiconductor device for appearance defects such as defective marks, bent leads, and sealing defects, the semiconductor device to be inspected is imaged with an imaging device such as a CCN camera while the semiconductor device to be inspected is irradiated with light. There is a method of comparing the obtained image with a reference pattern to determine whether the product is good or defective.

Problems to be Solved by the Invention At this time, if the semiconductor device is irradiated with disturbance light other than the original imaging light, accurate determination cannot be made. To solve this problem, a shielding plate may be provided around the semiconductor device to shield disturbance light other than the original light. However, in visual inspection equipment that sequentially inspects a large number of semiconductor devices while continuously transporting them, if the shielding plate is placed in a position that blocks external disturbance light, the semiconductor devices cannot be transported; If it is placed in a position where it does not interfere with traffic, sufficient shielding effect will not be obtained.

The present invention provides an appearance inspection device that solves these conventional problems.

Means for Solving the Problems The present invention provides a movable shielding plate near the inspection position, moves the shielding plate to the disturbance light shielding position in response to a signal indicating that the object to be inspected has arrived at the inspection position, and receives an imaging end signal. The shielding plate is moved out of the movement trajectory of the object to be inspected.

Function: By doing this, it is possible to reliably block external light without causing any hindrance to the conveyance of the object to be inspected. Furthermore, by moving the shielding plate in response to the arrival signal of the inspected object and the imaging end signal, it is possible to minimize the delay in transporting the inspected object due to the movement of the shielding plate.

EXAMPLE Hereinafter, an example of the appearance inspection apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of an external appearance inspection apparatus according to an embodiment of the present invention.

First, the configuration of this visual inspection apparatus will be explained. 0 1 is a semiconductor device to be inspected, 2 is a supply pallet for semiconductor devices 1, 3 is a storage pallet for non-defective semiconductor devices, 4 is a supply pick-up for semiconductor devices 1, 5 is a non-defective product A pickup for storing semiconductor devices, 6 a supply conveyor for semiconductor devices 1, 7
is a storage conveyor for semiconductor devices 1; 8 is a turntable;
9 is a turntable supply pickup of the semiconductor device 1;
10 is a turntable storage pickup for the semiconductor device 1, 11 is a camera for inspecting mark defects, and 12! L, 12b.

120.12d is a camera for inspecting lead defects, 13 is a camera for inspecting sealing defects, 14 is a storage pallet for defective semiconductor devices, 15 is a pickup for storing defective semiconductor devices, and 16 is a sol position of an empty inlet. 17 is a shielding plate provided above the turntable 8 so as to be movable up and down.

The operation of this embodiment will be explained below. The semiconductor devices 1 in the supply pallet 2 are transferred by the supply pickup 4 to the supply conveyor 6 in units of six. After moving in the direction of arrow C on the supply conveyor θ, it is transferred onto the turntable B by the turntable supply pink-up 9. Next, while rotating on this turntable 8 in the direction of arrow E, the mark defect inspection camera 11 and the lead defect inspection cameras 12a, 12b, 120, 1
2d and the sealing defect camera 13, and a processing section (not shown) determines whether the appearance is good or bad. Among the identified semiconductor devices, those deemed to be non-defective are transferred to the storage conveyor 7 by the turntable storage pickup 1o, and moved on the storage conveyor 7 in the direction indicated by the arrow. Then, the non-defective products storage pickup 6 stores the non-defective products into the non-defective storage pallet 3 in units of six. Also, the mark is defective.

Semiconductor devices 1 with bent leads or sealing defects are stored one by one by the defective storage pickup 16 into the defective storage pallet 14 according to the type of defect. During continuous inspection, when the semiconductor devices 1 in the supply pallet 2 run out, the supply pallet 2 moves in the direction of the arrow, is transferred to the empty pallet pool position 16 by a pallet transfer device (not shown), and is then supplied. Pallet 2 returns to its original position.

When the storage pallet 3 for non-defective products is full of semiconductor devices 1, the storage pallet 3 for non-defective products moves in the direction of arrow B, and the empty pallets are transferred to the empty pallet pool PO3 by the pallet transfer device.
Transferred from 16. Then, the non-defective storage pallet 3 returns to its original position.

By repeating the above operations, the appearance of the semiconductor device 1 is continuously inspected.

In such an appearance inspection apparatus, when the lead defect inspection camera 12a images the semiconductor device 1& immediately in front of it, the lead defect inspection camera 12d on the opposite side takes an image of the semiconductor device 1&.
However, the image is taken of the semiconductor device 1b located immediately in front of it. At this time, since the imaging light is irradiated in the directions of arrows G and H from near each lead defect inspection camera 12&, 12d, the lead defect inspection camera 121L is irradiated in the direction of arrow H from the opposite side. The light will be received as disturbance light, and the inspection accuracy will deteriorate.

Therefore, in this embodiment, a light shielding plate 17 is provided on the turntable 8 at the rear of the semiconductor device 1&, and is movable up and down, and during imaging, the shielding plate 17 is lowered to block the light from the lead defect inspection camera 12d.

FIGS. 2 and 3 are diagrams showing its structure and operation. Second
In the figure, 18 is a measurement head rotatably provided on the turntable 8, and 19 is a lead defect inspection camera 1.
This is a lighting device installed near 21L.

When the semiconductor device 12L reaches the inspection position shown in FIG. 1, an arrival signal as shown in FIG. 3 is output. In response to this arrival signal, a control circuit (not shown) is activated to lower the shielding plate 17, which had been in the raised position, as shown in FIG. This blocks light from light sources other than the illumination device 19 (for example, light indicated by H in FIG. 2). In synchronization with this, the semiconductor device 1a is irradiated with light G that can be imaged from the illumination device 19, and the semiconductor device 11L is illuminated by the camera 12 &
Lead bending is inspected by taking an image.

When a certain period of time (T in FIG. 3C) necessary for the visual inspection has elapsed, the camera output is turned off as shown in FIG. 3C. In synchronization with the timing of the end of this imaging, the shielding plate 17 is raised by the output of the control circuit, and the shielding plate 17 is moved to the semiconductor device 1a.
move back out of the movement trajectory. Note that as shown in Figure 3d, image processing continues even after the camera output is stopped;
Since the shielding plate 17 has already been raised, the semiconductor device 1a can be transported to the next inspection position without waiting for the end of the image processing operation.

In the above embodiment, the shielding plate 17 was provided at only one location on the turntable 8, but it goes without saying that it may be provided at each inspection position. It can also be applied to inspecting things other than semiconductor devices.

Effects of the Invention According to the present invention, it is possible to block external light without interfering with the transportation of the object to be inspected, and furthermore, since the movement of the shielding plate is controlled by the arrival signal of the object to be inspected and the imaging end signal, It is possible to minimize the delay in transporting the object to be inspected due to the movement of the shielding plate.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an appearance inspection apparatus according to an embodiment of the present invention, FIG. 2 is a side view of its main parts, and FIG. 3 is an explanatory diagram of its operation. 1.11L, 1b... Semiconductor device, 8...
・・Turn tape nope 121L・・・Camera for lead defect inspection, 17・・Shielding plate, 18・・・・
... Measuring head, 19... Lighting device. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3

Claims (1)

[Claims] a transport device that transports the object to be inspected to an inspection position; an imaging device that images the object to be inspected at the inspection position; an illumination device that irradiates the object to be imaged with an amount of light that can be imaged; a shielding plate that is movably provided nearby and blocks disturbance light irradiated onto the object to be inspected from a light source other than the illumination device, and a signal indicating that the object to be inspected has arrived at the inspection position to activate the shielding plate. an external appearance inspection apparatus, comprising: a control means for moving the shielding plate to a disturbance light shielding position and moving the shielding plate out of the movement locus of the object to be inspected in response to an imaging end signal from the imaging device.