JP2009109436A - Flatness measuring device - Google Patents

Abstract

A flatness measuring device capable of simplifying a structure by reducing the number of parts and easily performing movement control.
A horizontal axis guide rail is laid on the base 11 so as to extend along the object W above the sheet-like object W supported upright on the base 11. A horizontal axis slider 15 is supported on the horizontal axis guide rail 14 so as to be movable in the horizontal direction. A pair of vertical guide rails 16 are suspended from the horizontal axis slider 15 so as to extend in parallel along the front and back surfaces of the workpiece W. Each vertical guide rail 16 supports a pair of vertical sliders 19 so as to be movable in the vertical direction. A pair of sensors 20 are supported on each vertical slider 19 so as to face both the front and back surfaces of the workpiece W.
[Selection] Figure 1

Description

  The present invention relates to a flatness measuring apparatus for measuring the flatness of a sheet-like object to be measured such as a mask used when, for example, a liquid crystal panel is exposed.

  In general, when a predetermined pattern is exposed on a liquid crystal panel, a sheet-like mask made of quartz glass with a pattern is laminated on the surface of the panel coated with a photosensitive agent, and in this state, the mask is passed through the mask. By illuminating the panel, the pattern on the mask was copied onto the panel. In this case, if the front and back surfaces of the sheet-like mask are not finished to a predetermined flatness, the exposure accuracy may be reduced. Therefore, when manufacturing this type of mask, it is necessary to measure the flatness of both sides of the mask and finish the flatness within a predetermined value.

  Conventionally, configurations as shown in FIGS. 7 to 9 have been proposed as flatness measuring devices for measuring the flatness of a measurement object having a sheet shape such as a mask. In this conventional configuration, a gate-shaped support frame 32 is erected on a base 31. A sheet-like object to be measured W is detachably supported on a base 31 by a support device (not shown) so as to be arranged in a standing state in the support frame 32. A pair of longitudinal guide rails 33 are fixedly arranged on the inner surfaces of the both side frame portions 32 a of the support frame 32. A pair of longitudinal sliders 34 are supported on each longitudinal guide rail 33 so as to be movable in the longitudinal direction.

  A pair of horizontal axis guide rails 35 are supported between the vertical axis sliders 34 via a support plate 36 and an attachment block 37 so as to extend in parallel along the front and back surfaces of the workpiece W. A pair of horizontal axis sliders 38 are supported on each horizontal axis guide rail 35 so as to be movable in the horizontal direction. A pair of sensors 39 made of an optical sensor or the like is supported on the inner surface of each horizontal axis slider 38 so as to face both the front and back surfaces of the workpiece W.

  A pair of vertical axis sliders 34 are moved in synchronism with the vertical direction by a vertical axis driving mechanism including a servo motor and a ball screw (not shown), and a pair of vertical axis driving mechanisms including a linear motor or the like (not shown) The horizontal axis slider 38 is moved in the left-right direction. Accordingly, as indicated by solid lines and chain lines in FIG. 7, the sensors 39 on the respective horizontal axis sliders 38 are arranged to be opposed to arbitrary measurement positions on the front and back surfaces of the workpiece W. In this state, the flatness of the front and back surfaces of the workpiece W and the thickness of the workpiece W are measured by each sensor 39.

  However, in this conventional flatness measuring apparatus, two vertical axis guide rails 33 and two horizontal axis guide rails 35 are provided, and two vertical axis sliders 34 and two horizontal axis sliders 38 are provided. For this reason, there is a problem that the structure is complicated and the number of parts increases. Further, since the horizontal axis guide rail 35 is installed and supported between the pair of vertical axis sliders 34, the pair of vertical axis sliders 34 are synchronized by the vertical axis drive mechanism so that the horizontal axis guide rail 35 does not tilt. Need to be moved. For this reason, there also existed a problem that movement control became complicated.

  The present invention has been made paying attention to such problems existing in the prior art. The object is to provide a flatness measuring device that can simplify the structure by reducing the number of parts and that can easily perform movement control without having to move the slider in synchronization. is there.

  In order to achieve the above object, the invention according to claim 1 is configured to extend along the object to be measured above the object to be measured and a base for supporting the sheet-like object to be measured in an upright state. A horizontal axis guide rail installed on the base, a horizontal axis slider supported by the horizontal axis guide rail so as to be movable in the horizontal direction, and extending in parallel along the front and back surfaces of the object to be measured. A pair of vertical axis guide rails suspended from the horizontal axis slider, a pair of vertical axis sliders supported by the vertical axis guide rails so as to be movable in the vertical direction, and both front and back surfaces of the object to be measured. And a pair of sensors supported by each of the vertical axis sliders.

  Therefore, in the flatness measuring apparatus according to the first aspect of the present invention, it is not necessary to provide a pair of horizontal axis guide rails and horizontal axis sliders, and only one each may be provided. Therefore, the number of parts can be reduced and the structure can be simplified as compared with the conventional apparatus. Further, since it is not necessary to move the pair of vertical axis sliders supporting the sensor in synchronization, movement control can be easily performed.

  Further, in the above-mentioned configuration as in the second aspect of the present invention, a restricting member for restricting the movement of the lower end portions of both longitudinal guide rails may be provided on the base. When configured in this way, it is possible to prevent the possibility that lateral vibration occurs at the lower ends of the pair of vertical guide rails in the suspended state when the horizontal axis slider moves.

  According to a third aspect of the present invention, in the flatness measuring apparatus according to the first or second aspect, the horizontal axis slider is supported by the horizontal axis guide rail via a hydrostatic bearing mechanism, and the vertical axis slider is static. The gist is that it is supported by the longitudinal guide rail via a pressure bearing mechanism.

  According to a fourth aspect of the present invention, in the flatness measuring apparatus according to any one of the first to third aspects, the horizontal axis slider is reciprocated by a linear motor, and the vertical axis slider is reciprocated by a ball screw feed mechanism. The gist is that it is moved.

  According to a fifth aspect of the present invention, in the flatness measuring device according to the fourth aspect, the vertical axis slider is mounted at two positions above and below the vertical axis guide rail, and both sliders are coupled to each other by a universal joint. The gist is that one vertical slider is reciprocated by the ball screw feed mechanism, and the sensor is mounted on the other vertical slider.

  According to a sixth aspect of the present invention, in the flatness measuring apparatus according to any one of the first to fifth aspects, the vertical axis slider measures a horizontal dimension and a vertical dimension of the object to be measured. The gist of the present invention is that a laser line sensor is provided, and the sensor is provided so as to illuminate the object to be measured while tilting the belt-shaped laser beam.

  As described above, according to the present invention, it is possible to simplify the structure by reducing the number of parts, and it is not necessary to move the slider in synchronization, and movement control can be easily performed.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
As shown in FIGS. 1 to 3, a pair of support columns 12 are erected by brackets 13 on both sides of the upper surface of the base 11. A sheet-like object to be measured W is detachably supported on the base 11 by a support device (not shown) so as to be arranged in a standing state between the two columns 12. A horizontal axis guide rail 14 is installed between the upper ends of both columns 12 so as to extend along the workpiece W above the workpiece W. A horizontal axis slider 15 is supported on the horizontal axis guide rail 14 by a linear motor (not shown) so as to be movable in the horizontal direction via a static pressure air bearing as a static pressure bearing mechanism.

  As shown in FIGS. 1 to 4, a pair of vertical axis guide rails 16 are suspended from the horizontal axis slider 15 via a support plate 17 so as to extend in parallel along the front and back surfaces of the workpiece W. Has been. A pair of upper and lower gap holding members 18 are interposed between the vertical guide rails 16 to keep the gaps constant. A pair of longitudinal sliders 19 are supported on each longitudinal guide rail 16 via a hydrostatic air bearing as a hydrostatic bearing mechanism so as to be movable in the longitudinal direction. The two vertical axis sliders 19 are reciprocated by a ball screw feed mechanism that is rotated by the same drive source (not shown). A pair of sensors 20 such as optical sensors are supported on the inner surface of each vertical slider 19 so as to face both the front and back surfaces of the workpiece W. In this embodiment, a laser displacement meter is used as the sensor 20.

  As shown in FIGS. 1 and 3, a rail-like regulating member 21 is extended on the base 11 so as to extend along the workpiece W above the workpiece W. Then, the lower end inner surfaces of the both vertical guide rails 16 are brought into contact with both side surfaces of the restricting member 21, so that the movement of the lower end portions of the both vertical guide rails 16 is restricted from sideways.

Next, the operation of the flatness measuring apparatus configured as described above will be described.
Now, in this flatness measuring device, when measuring the flatness of the object W to be measured such as a mask, the object W to be measured is erected at a predetermined position on the base 11 by a support device (not shown). In this state, when the flatness measuring device is operated, the horizontal axis slider 15 is moved in the left-right direction by a horizontal axis drive mechanism including a linear motor (not shown) and a vertical axis including a servo motor (not shown) and a ball screw. The pair of vertical sliders 19 are moved in the vertical direction by the shaft driving mechanism. Thereby, as indicated by solid lines and chain lines in FIGS. 1 and 2, the sensors 20 on the respective vertical axis sliders 19 are arranged to be opposed to arbitrary measurement positions on the front and back surfaces of the workpiece W. At these measurement positions, the flatness of both the front and back surfaces of the workpiece W and the thickness of the workpiece W are measured by each sensor 20. The distance from the sensor 20 to the workpiece W is measured by the sensor 20 at a large number of vertical and horizontal coordinate points, and the flatness of the workpiece W is measured based on the measured values. Note that the shape and size of the workpiece W are also measured by a sensor (not shown) different from the sensor 20.

  As described above, in the flatness measuring apparatus of this embodiment, the pair of vertical axis guide rails 16 are supported by the horizontal axis slider 15 on the horizontal axis guide rail 14 in a suspended manner. For this reason, it is not necessary to provide each pair of the horizontal axis guide rail 14 and the horizontal axis slider 15, and it is sufficient to provide one each. Therefore, the number of parts can be reduced and the structure can be simplified as compared with the conventional apparatus. Further, since it is not necessary to move the pair of vertical axis sliders 19 that support the sensor 20 in synchronization, movement control can be easily performed.

  Furthermore, in the flatness measuring apparatus of this embodiment, a restricting member 21 for restricting the movement of the lower end portions of both longitudinal guide rails 16 is provided on the base 11. For this reason, when the horizontal axis slider 15 is moved, it is possible to prevent the possibility that horizontal vibration occurs at the lower ends of the pair of vertical axis guide rails 16 in the suspended state, and the distance between the object to be measured W and the sensor 20 can be reduced. The measurement accuracy can be improved by keeping constant.

(Example of change)
In addition, this embodiment can also be changed and embodied as follows.
In the embodiment shown in FIG. 5, a vertical axis slider 22 different from the vertical axis slider 19 is attached to the pair of vertical axis guide rails 16 so as to be movable in the vertical direction along the vertical axis guide rail 16. Yes. The vertical axis slider 19 and the vertical axis slider 22 are connected to each other by a universal joint 23 as a universal joint. The vertical axis slider 22 is mounted so as to be reciprocally movable in the vertical direction by a ball screw feed mechanism (not shown).

  In this embodiment, the vertical axis slider 22 is moved up and down by a ball screw feed mechanism (not shown), and the vertical axis slider 19 is connected to the vertical axis slider 22 via a universal joint 23. The swing of the vertical slider 22 caused by the ball screw swinging can be prevented from being transmitted to the vertical slider 19. For this reason, it is possible to stably and accurately measure the flatness of the workpiece W by the sensor 20 provided on the vertical slider 19.

  In the embodiment shown in FIG. 6, a laser line sensor 25 for measuring the vertical and horizontal dimensions of the workpiece W in addition to the sensor 20 with respect to the vertical slider 19 provided on the vertical guide rail 16 so as to be movable up and down. Is provided. The laser irradiation port 26 for irradiating the laser beam of the laser line sensor 25 is attached so as to be inclined by 45 degrees with respect to the horizontal line and the vertical line. Then, the laser beam sensor 25 irradiates the object to be measured W with a 45-degree tilted state, and the belt-shaped laser light is fixed by the both ends in the horizontal direction and the both ends in the vertical direction of the object W. A state in which the light is shielded by a certain amount is detected, and the horizontal and vertical dimensions of the workpiece W are provided in the control device from the two horizontal position coordinates and the two vertical position coordinates of the laser line sensor 25 at that time. Each computer performs calculations. Therefore, in this embodiment, the horizontal dimension and the vertical dimension of the workpiece W can be measured by one sensor 25, and the number of sensors can be reduced.

-In the said embodiment, the structure of the sensor etc. which have a contactor different from an optical sensor as the sensor 20 is used.
In the embodiment, a configuration such as a ball screw feeding mechanism that is different from the linear motor is used as the horizontal axis driving mechanism.

  In the embodiment, the vertical axis drive mechanism is different from the servo motor and the ball screw.

The front view which shows the flatness measuring apparatus of one Embodiment. The top view of the flatness measuring apparatus of FIG. Sectional drawing in the 3-3 line of FIG. Sectional drawing in the 4-4 line | wire of FIG. The longitudinal cross-sectional view which shows another embodiment of this invention. The partial front view which shows another embodiment of this invention. The front view which shows the conventional flatness measuring apparatus. Sectional drawing in the 6-6 line of FIG. Sectional drawing in the 7-7 line | wire of FIG.

Explanation of symbols

  W ... object to be measured, 11 ... base, 14 ... horizontal axis guide rail, 15 ... horizontal axis slider, 16 ... vertical axis guide rail, 19, 22 ... vertical axis slider, 20 ... sensor, 21 ... regulating member, 25 ... Laser line sensor.

Claims (6)

A base for supporting a sheet-like object to be measured in an upright state;
A horizontal axis guide rail constructed on a base so as to extend along the object to be measured above the object to be measured;
A horizontal axis slider supported by the horizontal axis guide rail so as to be movable in the horizontal direction;
A pair of vertical guide rails suspended by the horizontal slider so as to extend in parallel along the front and back surfaces of the object to be measured;
A pair of vertical axis sliders supported by each vertical axis guide rail so as to be movable in the vertical direction;
A flatness measuring apparatus comprising a pair of sensors supported by each vertical slider so as to face both the front and back surfaces of the object to be measured. The flatness measuring apparatus according to claim 1, wherein a restriction member is provided on the base for restricting movement of the lower end portions of both longitudinal guide rails. The horizontal axis slider is supported by the horizontal axis guide rail via a hydrostatic bearing mechanism, and the vertical axis slider is supported by the vertical axis guide rail via a hydrostatic bearing mechanism. The flatness measuring apparatus according to 1 or 2. The flatness according to any one of claims 1 to 3, wherein the horizontal axis slider is reciprocated by a linear motor, and the vertical axis slider is reciprocated by a ball screw feed mechanism. measuring device. The vertical axis slider is mounted at two locations on the vertical axis guide rail, and both sliders are connected to each other by a universal joint. One vertical axis slider is reciprocated by the ball screw feed mechanism, and the other vertical axis slider is connected. The flatness measuring device according to claim 4, wherein the sensor is mounted on the flatness measuring device. The vertical axis slider is provided with a laser line sensor for measuring a horizontal dimension and a vertical dimension of the object to be measured, and the sensor is provided so as to irradiate the object to be measured with an inclination of a belt-shaped laser beam. The flatness measuring device according to any one of claims 1 to 5, wherein

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