JPH0543083B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a camera holder, and more particularly to a camera holder used for image recognition of semiconductor pellets in the manufacture of semiconductor devices.

BACKGROUND TECHNOLOGY For example, in a pellet mounting process in the manufacture of semiconductor devices, a semiconductor wafer on which many elements have been formed is pasted onto an adhesive sheet, the semiconductor wafer is cut into many semiconductor pellet sections, and the adhesive The sheet is stretched and divided into individual pellets, which are then attached to a ring-shaped frame. The frame body (hereinafter referred to as a wafer ring) to which this adhesive sheet is attached is positioned and fixed on an XY table, and a large number of semiconductor pellets, each separated as described above, are sequentially positioned and pelletized using image recognition. Mounting is carried out.

A specific example of the camera holder in the semiconductor pellet image recognition apparatus used for manufacturing the semiconductor device will be described below with reference to FIGS. 7 to 9. In Figure 7, 1 is a base (not shown)
A support arm erected above, 2 a support block for supporting the lens barrel fixed to the distal end 1a of the support arm 1 by screws, etc., and 3 an insertion hole formed vertically through the support block 2. This lens barrel 3 is inserted through a hole (not shown) so as to be able to move up and down.
is fixed to the support arm 1 by bringing it into contact with the outer peripheral surface of the lens barrel 3 inserted into the support block 2, and is held vertically by the support block 2. Further, the positioning of the lens barrel 3 by vertical fine adjustment is performed by bringing an adjustment screw 6 threaded on an adjustment block 5 fixed to a part of the lens barrel 3 into contact with the upper end surface of the support arm 1. Reference numeral 7 denotes a television camera mounted on the upper end opening of the lens barrel 3 coaxially with the lens barrel 3. Although not shown, a monitor television is connected to the television camera 7. Reference numeral 8 denotes a zoom lens of an optical lens system screwed to the lower end opening of the lens barrel 3 coaxially with the lens barrel 3. After selecting the magnification of the zoom lens 8, the rotation of the zoom lens 8 is fixed with a fixing screw 9. Make a stop. 10 is a cylindrical zoom lens adapter attached to the lower end of the zoom lens 8, and 11 is a lighting device positioned and fixed to the side of the zoom lens adapter 10 via an L-shaped metal fitting 12. As shown in FIGS. 8 and 9, a half mirror 13 is provided at the lower end opening of the zoom lens adapter 10 at an angle of approximately 45° with respect to the optical axis of the lens barrel 3 and the zoom lens 8, that is, with respect to the camera optical axis lo. is fixed. Inside the lighting device 11,
A light source, for example, a halogen lamp 14 is housed, and a fixing screw 1 is installed in the front position of the halogen lamp 14.
A condenser lens 17 positioned by 6 is disposed, and the optical axis l ₁ of the condenser lens 17 is
It is set to form an angle of approximately 90 degrees with the camera optical axis lo. Further, in FIG. 7, 18 is an XY table provided below the lens barrel 3 on a base (not shown) on which the support frame 1 is erected;
On this XY table 18, a wafer ring 20 having a large number of semiconductor pellets 19, 19, . . . attached thereto is placed as described above.

In the pellet mounting process in the manufacture of semiconductor devices, the semiconductor pellets 19, 19, . . . of the wafer ring 20 placed on the XY table 18 are
Recognize the image in advance. This image recognition uses the above XY
The table 18 is moved in the X, Y, and θ directions to place a desired semiconductor pellet 19 on the camera optical axis lo. And the halogen lamp 14 of the lighting device 11
A portion of the light emitted from the semiconductor pellet 19 is reflected by the half mirror 13 and reaches the semiconductor pellet 19. The light reflected by the semiconductor pellet 19 passes through the half mirror 13, the zoom lens 8, and the lens barrel 3, and reaches the television camera 7. This reflected light is detected by the television camera 7 and image processed,
The detection signal is sent to a monitor television, and the semiconductor pellet 19 is positioned while monitoring the image displayed on the monitor television. After positioning the semiconductor pellet 19, pellet mounting is performed.

Problems to be Solved by the Invention In the above-mentioned conventional camera holder, the camera optical axis lo must be set reliably perpendicular to the semiconductor pellets 19, 19, etc. during image recognition. Attachment to arm 1 is important. However, in manufacturing each of the parts such as the support arm 1, the support block 2, and the lens barrel 3, there are errors in the machining accuracy, and furthermore, there is a limit to the improvement of this machining accuracy. Therefore, in the camera holder, the machining accuracy errors of these parts are accumulated, and as a result, the camera holder's optical axis lo
It was difficult to hold the image vertically, and misalignment occurred, making it difficult to perform good image recognition. Therefore, in order to correct the above-mentioned errors in processing accuracy, for example, a spacer may be inserted between the support arm 1 and the support block 2, or the camera holder with the above-mentioned parts assembled may be disassembled and then machined. After performing correction processing, the parts were reassembled, and image recognition was performed on a trial basis. Even with this, if the optical axis of the camera is not vertical, the above-mentioned disassembly and correction processing of the parts has to be repeated. Therefore, there are problems in that not only is the adjustment time-consuming and the number of man-hours increased, but also the fine adjustment by correction processing is difficult because it requires the skill of the operator.

Furthermore, the light emitted by the halogen lamp 14 of the illumination device 11 and reflected by the half mirror 13 of the zoom lens adapter 10 must be uniform parallel light with respect to the camera optical axis lo. This is because when the irradiation light is incident on the semiconductor pellets 19, 19... from an oblique direction, the semiconductor pellets 19, 19...
A shadow is generated, or a semiconductor pellet 19,
This is because the reflected light on the semiconductor pellets 19, 19... is deviated from the camera optical axis lo, making it difficult to recognize the semiconductor pellets 19, 19... as images. However, as in the case of the lens barrel 3, the zoom lens adapter 10 and the L-shaped metal fitting 12
Errors in machining accuracy of parts such as halogen lamp 1
Due to the asymmetry of the thickness of the cover glass 4, eccentricity of the filament, etc., the light irradiated onto the semiconductor pellets 19, 19... could not easily become parallel to the camera optical axis lo. As a result, good image recognition cannot be performed, and the illumination state by the illumination device 11 must be corrected, and the fine adjustment thereof is also extremely difficult, as in the case of the lens barrel 3.

Means for Solving the Problems The present invention was proposed in view of the above problems, and technical means for solving the problems are as follows:
At the tip of the support arm, there is a lens barrel supported by a spherical bearing so as to be tiltable in any direction and held hanging down, an optical lens system coaxially attached to the lower end of the lens barrel, and a lens barrel attached to the bottom of the optical lens system. An illumination device that is supported by a spherical bearing so as to be tiltable in any direction and is held hanging down, and that illuminates the object to be measured that is placed below; The device is equipped with a camera that detects the light reflected on the object to be measured and processes the image.

Effect: According to the above technical means, by supporting the lens barrel on the support arm with a spherical bearing, the lens barrel can be tilted in any direction, and the illumination device is supported on the optical lens system with a spherical bearing. As a result, the illumination device can also be tilted in any direction, making it easy to finely adjust the positioning of the lens barrel and the illumination device, allowing for good image recognition.

Embodiment A first embodiment of the camera holder according to the present invention will be described below.
This will be explained with reference to FIGS. 6 to 6. In FIGS. 1 to 3, 21 is a support arm erected on a base (not shown), and 22 is a support block fixed to the tip 21a of the support arm 21 for supporting the lens barrel. This support block 22 includes a bearing stand 23 having an insertion hole 23a formed therethrough in the vertical direction, and a bearing holder 24 screwed onto the bearing stand 23 and having a communication hole 24a formed therethrough communicating with the insertion hole 23a. It consists of. Reference numeral 25 denotes a lens barrel inserted into each of the insertion holes 23a and 24a of the support block 22, and 26 is a spherical bearing that supports the lens barrel 25 on the support block 22 so as to be tiltable in any direction and holds it hanging down. As shown in FIG. 2, 26 includes an inner ball 26a having a convex outer circumferential surface fitted to the outer circumferential surface of the lens barrel 25 so as to be slidable in the vertical direction; An outer shell 2 with a concave inner circumferential surface is pressed and fixed between the bearing stand 23 and the bearing retainer 24 of the support block 22.
6b. Support arm 21 of the lens barrel 25
As shown in FIG. 3, positioning screws 27a, 27b, and 27c are screwed into the bearing stand 23 of the support block 22 at three locations at approximately 120° intervals.
The lens barrel 25 is held perpendicularly to the support block 22 by bringing the lens barrel 25 into contact with the outer peripheral surface of the lens barrel 25. Further, fine vertical adjustment of the lens barrel 25 can be performed using the adjustment block 2 fixed to the lens barrel 25, since the lens barrel 25 is slidably provided on the inner sphere 26a of the spherical bearing 26.
This is done by bringing the adjustment screw 29 threaded into the screw 8 into contact with the upper end surface of the bearing presser 24 of the support arm 22. 30 is a television camera coaxially attached to the upper end opening of the lens barrel 25, as in the past, and 31 is an optical zoom lens coaxially screwed to the lower end opening of the lens barrel 25, as in the past. After selecting the magnification, use the fixing screw 32 to tighten the zoom lens 3.
Perform the rotation stopper in step 1. 33 is the zoom lens 3 mentioned above.
An illumination device 34 is mounted on the lower end of 1 by a spherical bearing, which will be described later, so as to be able to tilt in any direction and is held hanging down.
On this XY table 34,
A wafer ring 36 to which a large number of semiconductor pellets 35, 35, . . . are attached is placed. FIG. 4 is a partial sectional view of the lighting device 33 comprising a housing 37 having an L-shaped cross section.
Reference numeral 8 denotes the spherical bearing, and the spherical bearing 38 includes an inner sphere 38a having a convex outer circumferential surface fixed to a cylindrical portion 39a of a cylindrical body 39 provided at the lower part of the zoom lens 31.
and an outer shell 38b having a concave inner peripheral surface, which fits into the inner sphere 38a and is attached to the upper opening of the housing 37. Numerals 40, 40 are positioning screws screwed onto the flange portion 39b of the cylindrical body 39, and the housing 37 is positioned by bringing the positioning screws 40, 40 into contact with the upper end surface of the housing 37. 41 is a half mirror fixed at an angle of approximately 45° to the camera optical axis lo via a mounting member 42 below the upper end opening of the housing 37; 43 is a drilled hole in the housing 37 at a position below the half mirror 41; Transparent window installed, 44
is a halogen lamp arranged on the side of the half mirror 41, that is, in a direction perpendicular to the camera optical axis lo, and in front of this halogen lamp 44, although not shown, a condenser lens is arranged as in the conventional case. .

Image recognition in the pellet mounting process in the manufacture of semiconductor devices is carried out in the same way as in the conventional method. A semiconductor pellet 35 placed on the camera optical axis lo is moved in half by the movement of an XY table 34 using a halogen lamp 44 of an illumination device 33. Irradiation is performed through the mirror 41. Then, the light reflected on the semiconductor pellet 35 is detected by the television camera 30, and the detection signal is sent to a monitor television connected to the television camera 30, and the semiconductor pellet 35 is detected while monitoring the image on the monitor television. Positioning and pellet mounting are performed.

When recognizing the above image, the lens barrel 25 is adjusted by the adjustment screw 29.
After finely adjusting the vertical position of the semiconductor pellet 35, the camera optical axis lo, that is, the lens barrel 25 must be set perpendicular to the semiconductor pellet 35, as described above. This tilt correction for holding the lens barrel 25 vertically is performed with the lens barrel 25 attached while monitoring images from the television camera 30 on a monitor television. When the lens barrel 25 is inclined with respect to the semiconductor pellet 35 as shown in FIG.
lo'), since the lens barrel 25 is supported by the support block 22 with a spherical bearing 26 so as to be tiltable in any direction,
The positioning screws 27a, 27b, and 27c (see FIG. 3) are moved in and out as appropriate, and the lens barrel 25 is tilted in the direction of the solid line arrow in FIG. Hold it in the vertical position shown in Figure 2.

In addition, at the same time as the tilt of the lens barrel 25 is corrected, the light irradiated from the illumination device 33 onto the semiconductor pellet 35 must be made uniform and parallel to the camera optical axis lo. Corrections must be made. The tilt correction of the illumination device 33 is also performed on the television camera 30 with the illumination device 33 attached, as in the case of the lens barrel 25 described above.
This is done while monitoring the images on a monitor TV. For example, as shown in FIG. 6, when the optical axis l ₁ ' of the light emitted from the halogen lamp 44 of the illumination device 33 and reflected by the half mirror 41 is inclined with respect to the camera optical axis lo, the illumination device Since the housing 37 of 33 is supported under the zoom lens 31 by a spherical bearing 38 so as to be tiltable in any direction,
Protrude and retract the positioning screws 40 and 40 as appropriate, and insert the housing 37 into the inner ball 38a of the spherical bearing 38.
is tilted in the direction of the solid line arrow in FIG. 6 about the center of curvature O' of the half mirror ₄₁ , and as shown in FIG. The light is made uniform and parallel to the camera optical axis lo and is irradiated onto the semiconductor pellet 35.

Effects of the Invention According to the present invention, since the lens barrel and the illumination device are supported by spherical bearings so as to be tiltable in any direction, there is no need to require high accuracy in machining each component, and this machining precision error etc. Even if the camera optical axis of the lens barrel is not perpendicular to the object to be measured due to After each part is assembled, fine adjustments can be made quickly and easily without disassembling the lens barrel and illumination device in their attached state.
Therefore, the lens barrel can be held perpendicular to the object to be measured, and the illumination device can be aligned with the camera optical axis without requiring the skill of a conventional operator. This greatly improves work efficiency and makes it easier to perform good image recognition.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the camera holder according to the present invention, Fig. 2 is an enlarged sectional view of the main part of Fig. 1 showing the attached state of the lens barrel, and Fig. 3 is A of Fig. 2.
4 is an enlarged sectional view of the main part of FIG. 1 showing the installation state of the illumination device; FIG. 5 is an enlarged sectional view of the main part for explaining tilt correction of the lens barrel;
FIG. 6 is an enlarged sectional view of a main part for explaining tilt correction of the illumination device. 7 is a front view showing a specific example of a conventional camera holder, FIG. 8 is an enlarged top view showing the illumination device of FIG. 7, and FIG. 9 is a front sectional view of FIG. 8. 21...Support arm, 21a...Tip part, 25
... Lens barrel, 26 ... Spherical bearing, 30 ... Camera,
31... Optical lens system (zoom lens), 33...
...Lighting device, 35...Object to be measured (semiconductor pellet), 38...Spherical bearing.

Claims (1)

[Claims] 1. A lens barrel supported by a spherical bearing so as to be tiltable in any direction and held hanging at the tip of a support arm, an optical lens system coaxially attached to the lower end of the lens barrel, and a lower part of the optical lens system. an illumination device which is supported by a spherical bearing so as to be tiltable in any direction and is held hanging down, and which irradiates the object to be measured which is arranged below; A camera holder characterized by comprising a camera that detects the light irradiated and reflected on the object to be measured and processes the image.