JPH09287928A - Apparatus for visual inspection of ic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure all leads at four sides of an IC at high speed, by projecting a laser light from over head slantwise direction to a lead of an IC to be inspected, in a manner not parallel to the sides, and detecting a position of a condensed reflected light. SOLUTION: A laser light 10a from a laser device 1 is converged at a projecting lens 3, which illuminates one point on a flat part of a lead of an IC 30. This reflected light 10b, through a condensing lens 4, reaches a one-dimensional sensor 5 at an image formation point of the condensing lens 4. If a front-end part of the lead is at a different height, the image formation position of the reflected light 10b on the one-dimensional sensor 5 differs, and the one- dimensional sensor 5 outputs signals A, B to both ends in accordance with the image formation position. A height detection circuit processes (A-B)/(A+B) from the signals A, B, thereby calculating the height of the lead. In this case, since the laser light 10a is irradiated from overhead slantwise direction to the lead of the IC 30 at an angle 45 to the side, the reflected light 10b is not shut by an inclined part of the lead. Moreover, since a stage 8 moves a tray loading the IC 30, all the leads of the IC 30 can be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC visual inspection device,
In particular, the present invention relates to an IC visual inspection apparatus for inspecting a visual inspection of a surface mount IC having a large number of leads on four sides in a tray.

[0002]

2. Description of the Related Art As a conventional measuring device, there is, for example, one disclosed in Japanese Patent Laid-Open No. 3-77006. this is,
The object is irradiated with laser light, the reflected light is received by the semiconductor position detector, and the output signal thereof is processed to measure the shape of the object.

Next, a conventional IC visual inspection apparatus will be described in detail with reference to the drawings. FIG. 7 is a perspective view showing an example of a conventional IC appearance inspection apparatus, FIG. 8 is a plan view showing a laser scanning direction of a lead located on a side parallel to the laser scanning direction, and FIG. FIG. 10 is a side view showing the route.
FIG. 4 is a side view showing names of respective parts of the IC to be inspected.

The IC visual inspection apparatus shown in FIG.
Laser device 1 for emitting 0a, galvano mirror 2 for scanning laser light 10a, and laser light 10a scanned by galvano mirror 2 are focused and scanned in parallel to IC 30.
The projection lens 3 that illuminates the side with
A condenser lens 4 for condensing the reflected light 10b from 0, a one-dimensional sensor 5 for detecting the position of the reflected light 10b condensed by the condenser lens 4, and a height calculated from the output of the one-dimensional sensor 5. Height detection circuit 6 and the tray 40 on which the IC 30 is placed
And a stage 8 for moving the.

The stage 8 moves in the -X direction, and as shown in FIGS. 8 and 9, the laser light 10a begins to strike the lead flat portion 31 from the side parallel to the laser scanning direction Y.
Since the reflected light is blocked by the lead slope portion 32, the leads on this side are not measured.

Laser light 10 emitted from the laser device 1
The a is scanned in a fixed direction by the galvanometer mirror 2, and the laser light 10a passing through the light projecting lens 3 is converged and scanned in parallel. On the side orthogonal to the laser scanning direction Y, the reflected light 10b of the laser light passes through the condenser lens 4 and reaches the one-dimensional sensor 5 located at the image forming point of the light receiving lens 4 without being blocked by the lead slope portion 32. . If the height of the lead tip portion 31 is different, the image formation position on the one-dimensional sensor 5 of the reflected light 10b is different, and the one-dimensional sensor 5 outputs signals A and B to both ends according to the image formation position. The height of the lead can be obtained by processing the signals A and B in the height detection circuit 6 with the value (AB) / (A + B) representing the height.

[0007]

In the conventional IC visual inspection apparatus described above, in the lead located on the side parallel to the scanning direction of the laser, the reflected light from the flat lead portion is blocked by the lead slope portion, and measurement can be performed. In addition, if the incident angle is made shallow so that it is not blocked by the leads, the height detection sensitivity will be low, which is not practical.To measure the leads on the four sides, rotate one head by 90 ° or scan There is a drawback that it is necessary to have two inspection heads whose directions are orthogonal to each other.

[0008]

An IC appearance inspection apparatus according to a first aspect of the present invention comprises a projection lens for irradiating a laser beam onto an IC lead obliquely from above and in a direction not parallel to a side of an IC to be inspected. A condenser lens that collects the reflected light from the lead of the IC to be inspected, a one-dimensional sensor that detects the position of the reflected light that is condensed by the condenser lens, and a height from the output of the one-dimensional sensor. It is configured to include a height detection circuit for calculating and a stage for moving a tray on which the IC to be inspected is placed in a horizontal direction.

An IC visual inspection apparatus of a second invention is a laser apparatus for emitting a laser beam, a scanning apparatus for scanning the laser beam in a minute range including a lead tip portion, and a laser beam scanned by the scanning apparatus. In addition, a light projecting lens that scans in parallel and irradiates the leads of the IC in a direction that is not parallel to the sides of the IC, a condensing lens that collects the reflected light from the IC, and a condensing lens collects the light. A one-dimensional sensor that detects the position of reflected light, a height detection circuit that calculates the height from the output of the one-dimensional sensor, and the value obtained by the height detection circuit is corrected for the angle corresponding to the non-parallel direction. And an angle correction means for performing the above, and a stage for moving the tray on which the IC is placed.

An IC visual inspection apparatus according to a third aspect of the present invention includes a laser device for emitting a laser beam, a scanning device for scanning the laser beam over the entire IC in a wide range, and a laser beam scanned by the scanning device. A light projecting lens that scans in parallel and irradiates in a direction that is not parallel to the sides of the IC, a condenser lens that collects the reflected light from the IC lead and mold surface, and a reflection that is condensed by the condenser lens. A one-dimensional sensor that detects the position of light, a height detection circuit that calculates the height from the output of the one-dimensional sensor, and the value obtained by the height detection circuit is corrected for the angle corresponding to the non-parallel direction. Angle correction means to perform,
And a stage for moving the tray on which the IC is placed.

An IC visual inspection apparatus according to a fourth aspect of the present invention comprises (A) a stage for laterally moving an IC to be inspected stored in a tray, and (B) a diagonal length of the IC package to be inspected. , The IC width to be inspected has a scanning width of a length equal to or greater than twice the length of the lead of the IC to be inspected,
Optical scanning means for scanning the inspection light in a direction non-parallel to each side of the package, and setting the incident angle of the inspection light with respect to the surface of the IC package to be inspected obliquely, (C) irradiating the inspection light The light receiving means for capturing the reflected light generated by the above, converting it into an electric signal and outputting the electric signal, and (D) calculating the height of the IC to be inspected based on the electric signal and outputting the height signal. It comprises a height calculating means and (E) an angle correcting means for correcting the angle corresponding to the non-parallel direction based on the height signal.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the present invention. The appearance inspection apparatus shown in FIG. 1 includes a laser device 1 that emits a laser beam, a laser beam 10a, and an IC3.
The projection lens 3 that irradiates the 0 lead at an angle of 45 ° to the side of the IC, the condenser lens 4 that condenses the reflected light 10b from the lead of the IC 30, and the reflection that is condensed by the condenser lens 4. A one-dimensional sensor 5 for detecting the position of the light 10b and a height detection circuit 6 for calculating the height from the output of the one-dimensional sensor 5.
And a stage 8 that moves a tray 40 on which the IC 30 is placed.

Laser light 10 emitted from the laser device 1
a is passed through the light projecting lens 3 and is converged to lead flat portion 3
The reflected light 10b hits a certain point of 1 and goes toward the condenser lens 4. Laser reflected light 10b passing through the condenser lens 4
Reaches the one-dimensional sensor 5 located at the image forming point of the condenser lens 4. If the height of the lead tip 31 is different, the reflected light 10
b, the image forming position on the one-dimensional sensor 5 is different, and the one-dimensional sensor 5 outputs the signals A and B to both ends according to the image forming position. The height of the lead can be obtained by processing with the value (AB) / (A + B) indicating the height.

As shown in FIG. 2, the laser light 10a is emitted from the IC
45 to the lead of 30 from diagonally above and to the side of IC30
Since the reflected light 10b is radiated at an angle of 10 °, the reflected light 10b is moved by the tray 40 on which the IC 30 is mounted on the stage 8 without being blocked by the lead slope 32 in all the leads.
All C30 leads can be measured.

FIG. 3 is a perspective view showing a second embodiment of the present invention. The appearance inspection apparatus shown in FIG. 3 includes a laser apparatus 1 that emits a laser beam and a galvano mirror 2 that scans a laser beam 10a in a minute range including a flat lead portion 31 of an IC 30.
And a projection lens 3 for converging the laser beam 10a scanned by the galvanometer mirror 2 and scanning it in parallel to irradiate the leads of the IC 30 with an angle of 45 ° with respect to the side of the IC 30,
Condensing lens 4 for condensing the reflected light 10b from the 0 lead
The one-dimensional sensor 5 that detects the position of the reflected light 10b condensed by the condenser lens 4, the height detection circuit 6 that calculates the height from the output of the one-dimensional sensor 5, and the height detection circuit 6 45 ° correction circuit 7 for correcting the obtained value by an angle corresponding to 45 °
And a stage 8 that moves a tray 40 on which the IC 30 is placed.

Laser light 10 emitted from the laser device 1
The a is scanned in a fixed direction by the galvanometer mirror 2, and the laser light 10a passing through the light projecting lens 3 is converged and scanned in parallel. FIG. 4 shows a momentary state of the scanned laser light. The laser light 10 a converged on a certain point on the lead flat portion 31 hits, and the reflected light 10 b is directed toward the condenser lens 4. If the scanning direction is parallel to the side where the lead is located, the reflected light 10b is blocked by the lead slope portion 32 and the one-dimensional sensor 5 as shown in FIG.
However, in the IC visual inspection apparatus of the present invention, since the scanning direction has an angle of 45 ° with the side of the IC as shown in FIG. 4, the reflected light 10b is not blocked by the lead slope portion 32. It reaches the one-dimensional sensor 5 located at the image forming point of the light receiving lens 4 through the condensing lens 4, and the height detection circuit 8 calculates the height.

In the IC visual inspection apparatus of the present invention, the IC 30
Since the reflected light 10b from the flat lead portion 31 is not blocked in all the leads of the above, the tray 40 on which the IC 30 is mounted is moved on the stage 8 without rotating the inspection head or having two inspection heads. By doing so, all leads of the IC 30 can be measured at high speed.

FIG. 5 is a perspective view showing a third embodiment of the present invention. The appearance inspection apparatus shown in FIG.
The laser device 1 for emitting a laser beam and the laser light 10a to the IC 30
The galvano-mirror 2 that scans a wide area as a whole and the laser beam 10a that is scanned by the galvano-mirror 2 are condensed and scanned in parallel to the lead of the IC 30 to the side of the IC 30 by 45 degrees.
A projection lens 3 for irradiating at an angle of °, a condenser lens 4 for condensing the laser reflected light 10b from the IC 30, and a one-dimensional sensor 5 for detecting the position of the reflected light condensed by the condensing lens 4. A height detection circuit 6 for calculating the height from the output of the one-dimensional sensor 5, a 45 ° correction circuit 7 for correcting the value obtained by the height detection circuit 6 by an angle equivalent to 45 °, and a tray on which an IC 30 is mounted. And a stage 8 that moves 40.

Laser light 10 emitted from the laser device 1
The a is scanned in a fixed direction by the galvanometer mirror 2, and the laser light 10a passing through the light projecting lens 3 is converged and scanned in parallel. The laser light 10a converged on a certain point on the lead flat portion 31 hits, and the reflected light 10b is directed toward the condenser lens 4. Since the scanning direction has an angle of 45 ° with the side of the IC, the one-dimensional sensor positioned at the image forming point of the light receiving lens 4 through the condenser lens 4 without the reflected light 10b being blocked by the lead slope portion 32 5 is reached and the lead height can be obtained. This pattern is shown in FIG.

In the IC visual inspection apparatus of the present invention, the IC 30
Since the reflected light 10b from the lead flat portion 31 is not blocked in all the leads of the above, the tray 40 on which the IC 30 is mounted is mounted on the stage 8 without rotating the inspection head or having two inspection heads. By moving in the direction, all leads of the IC can be measured at high speed. At the same time, the defective shape generated on the mold surface 33 of the IC can be measured.

Although a galvanometer mirror is shown as the scanning means in this example, other scanning means such as a polygon mirror and an AO deflector are equivalent.

[0023]

The effect of the IC appearance inspection apparatus of the present invention is that the laser scanning direction has an angle of 45 ° with the side of the IC.
The reflected light of the laser light that hits the tip end of the lead of C reaches the one-dimensional sensor without being blocked by the lead slope portion of any lead.
There is an effect that measurement can be performed at high speed without rotating one inspection head or having two inspection heads.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a plan view showing a route of the laser shown in FIG.

FIG. 3 is a perspective view showing a second embodiment of the present invention.

FIG. 4 is a plan view showing a scanning direction of the laser shown in FIG.

FIG. 5 is a perspective view showing a third embodiment of the present invention.

6 is a plan view showing a scanning direction and a path of the laser shown in FIG.

FIG. 7 is a perspective view showing an example of the related art.

8 is a top view showing a laser scanning state of a lead located on a side parallel to the scanning direction of the laser shown in FIG.

9 is a side view showing a path of laser light in a lead located on a side parallel to the scanning direction of the laser shown in FIG.

FIG. 10 is a side view illustrating each part of the IC to be measured.

[Explanation of symbols]

 1 Laser Device 2 Galvanometer Mirror 3 Projection Lens 4 Condenser Lens 5 One-dimensional Sensor 6 Height Detection Circuit 7 45 ° Correction Circuit 8 Stage 10a Laser Light 10b Laser Reflection Light 30 IC 31 Lead Tip 32 Lead Slope 33 Mold Surface 40 trays

Claims (9)

[Claims] 1. A light projecting lens for irradiating a laser beam onto an IC lead obliquely from above in a direction not parallel to a side of an IC to be inspected, and a condenser for condensing reflected light from the lead of the IC to be inspected. A lens, a one-dimensional sensor that detects the position of the reflected light condensed by the condenser lens, a height detection circuit that calculates the height from the output of the one-dimensional sensor, and a tray on which the IC to be inspected is mounted. An IC visual inspection apparatus, comprising: a stage that moves in a horizontal direction. 2. A laser device which emits a laser beam, a scanning device which scans the laser beam in a minute range including a lead tip portion, and a laser beam which is scanned by the scanning device is focused and scanned in parallel to form an IC. A projection lens that irradiates the lead in a direction that is not parallel to the side of the IC, a condenser lens that condenses the reflected light from the IC, and one-dimensional detection of the position of the reflected light that is condensed by the condensing lens. The sensor, the height detection circuit that calculates the height from the output of the one-dimensional sensor, the angle correction means that corrects the value obtained by the height detection circuit for the angle corresponding to the non-parallel direction, and the IC An IC visual inspection apparatus, comprising: a stage for moving a tray on which it is placed. 3. A laser device that emits laser light, a scanning device that scans the laser light over a wide area of the IC, and a laser device that condenses and scans the laser light scanned by the scanning device in parallel to the IC.
Projector lens that irradiates in a direction not parallel to the side of the
Condensing lens that collects the reflected light from the lead and the mold surface, a one-dimensional sensor that detects the position of the reflected light that is condensed by the condensing lens, and a height that calculates the height from the output of the one-dimensional sensor. An IC including a height detection circuit, an angle correction unit that corrects a value obtained by the height detection circuit for an angle corresponding to the non-parallel direction, and a stage that moves a tray on which the IC is placed. Appearance inspection device. 4. (A) IC to be inspected in a state of being stored in a tray
And (B) the IC to be inspected
The package has a scan width that is equal to the length of the diagonal of the package plus twice or more the length of the leads of the IC to be inspected, and is not parallel to each side of the IC package to be inspected. Optical scanning means for scanning the inspection light in various directions and setting the incident angle of the inspection light with respect to the surface of the IC package to be inspected obliquely, and (C) capturing reflected light generated by irradiating the inspection light. And (D) the light receiving means for converting the electric signal into an electric signal and outputting the electric signal, based on the electric signal.
A height calculating means for calculating the height of C and outputting a height signal; and (E) an angle correcting means for correcting the angle corresponding to the non-parallel direction based on the height signal.
An IC visual inspection device comprising: 5. The IC visual inspection apparatus according to claim 4, wherein a galvanometer is used as the optical scanning means. 6. The IC visual inspection apparatus according to claim 4, wherein a polygon mirror is used as the optical scanning means. 7. The IC visual inspection apparatus according to claim 4, wherein an AO deflector is used as the optical scanning means. 8. A PSD is used for the light receiving means.
The IC appearance inspection device described. 9. The IC visual inspection apparatus according to claim 4, wherein a one-dimensional CCD is used as the light receiving means.