JPH045659A - Photomask substrate supporting device - Google Patents

Abstract

PURPOSE:To improve accuracy by engaging one piece among 3 pieces of balls mounted to a photomask substrate with a pit on a stage side, engaging another one piece with a groove to regulate the rotating angle of the substrate and allowing the other one piece to regulate the inclination of the substrate. CONSTITUTION:The pits 5 each having a V-shaped section are provided in the positions respectively corresponding to the spherical bodies 3a, 3b, 3c atop a stage 2 and the V-grooves 6 are provided in these pits 5. The spherical bodies support the photomask substrate 1 to the stage 2 by respectively engaging with these grooves. The ball 3a is the 1st supporting point which is the center of the axis of rotation of the substrate 1. The ball 3b is the 2nd supporting point to determine the rotating angle of the substrate 1. The ball 3c is the 3rd supporting point to regulate the inclination of the substrate 1. The generation of a deviation in the substrate 1 is obviated in this way even if the substrate 1 is supported by the pressure of about the gravity to prevent the straining of the substrate 1. The accuracy of plotting positions is thus enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photomask substrate support device for supporting a photomask substrate used in an exposure apparatus, a coordinate measuring device, or the like.

[Conventional technology]

12 and 13 show a conventional photomask substrate support device, in which a vacuum groove (21
) is formed and a vacuum 71 is drawn from the exhaust boat (22).
By evacuating stage 1 (21), the photomask substrate is attracted and supported substantially parallel to stage (2).

In addition, as another conventional photomask substrate support device, the first
There are those shown in Figures 4 and 15, and in stage (2),
Height adjustment screw 31), push-up rod (32), lever (
33) and a spring (34) to mechanically clamp a small area of the photomask substrate (1). Like an electron beam exposure device, the stage is in a vacuum, so it is not necessary to use a vacuum. It is applied when adsorption is not possible.

[Problem to be solved by the invention]

In the former type of conventional photomask substrate support device as described above, the photomask substrate is fixed to the stage by vacuum suction, so if the flatness of this suction surface is not sufficient, the photomask The substrate warped, resulting in poor drawing position accuracy in the exposure apparatus. In addition, in the latter case, the tiny surface of the photomask substrate is mechanically clamped and supported, so it is necessary to clamp the photomask substrate with a sufficiently large pressure to prevent it from shifting due to acceleration during stage movement. was there.

Therefore, this pressure sometimes distorts the photomask substrate and deteriorates the precision of the drawing position.

Furthermore, if these were a coordinate measuring device instead of the exposure bag W, there would be a problem of errors in the coordinate measurement values for the same reason.

This invention was made to solve the above problems, and provides a photomask in which the supported photomask substrate is not distorted and the photomask substrate does not shift due to acceleration during stage movement. The purpose is to obtain a substrate support device.

[Means to solve the problem]

The photomask substrate support device according to the present invention identifies balls at three locations on the lower surface of the photomask substrate, and provides an engaging portion to receive the balls on the stage side of the exposure device or coordinate measuring device, thereby supporting the substrate. Provide support.

[For production]

In this invention, one of the three balls attached to the photomask substrate is engaged with the bit on the stage side and centered on the rotation axis of the photomask substrate, and the other one is engaged with the groove. In addition, the rotation angle of the photomask substrate is regulated. The remaining one is placed on a flat part to restrict only the inclination of the photomask substrate.

〔Example〕

FIGS. 1 to 5 show an embodiment of the present invention, in which spheres (3a), (3b), and (3c) are attached to adhesives (4 ) are glued together. On the top surface of the stage (2), there is a bit (5) with a V-shaped cross section at the positions corresponding to the spheres (3a), (3b), and (3c), and a V-shape (6) facing this bit (5). and flat surface (7)
are provided, and the spheres (3a), (3b),
(3c) are engaged with each other, so that the stage (2
) supports the photomask substrate (1).

The sphere (3a) is the first support point that is the rotation axis center of the photomask substrate (1), and the sphere (3b) is the rotation axis center of the photomask substrate (1).
The second support point that determines the rotation angle of the sphere (3c)
serves as a third support point that regulates the inclination of the photomask substrate (1).

With this configuration, even though the photomask substrate (1) is supported with a pressure similar to gravity that does not cause distortion to the photomask substrate (1), writing can be performed without causing displacement of the photomask substrate (1). Position accuracy can be improved.

In the above embodiment, a V-shaped bit and a groove were used, but as shown in Fig. 6, a cylindrical or square bit (
5), grooves (6) may be used, or U-shaped bits (5) and ridges (6) may be used as shown in FIG. moreover,
Instead of a sphere, as shown in Figure 8, a hemisphere (3d),
Alternatively, as shown in FIG. 9, it may be a cylindrical body (3e) as long as it has an arcuate cross section.

Further, although the spherical protrusion side is provided on the photomask substrate, conversely, the protrusion side may be placed on the stage and pits and grooves may be formed on the photomask substrate.

Furthermore, as shown in FIGS. 10 and 11,
5), the sphere (3a) that engages with the V-shaped lever 6), -(3b)
) is fixed to the photomask substrate (1), and various modifications are possible, such as fixing the sphere (3c) that contacts the flat surface (7) to the stage (2).

In addition, adhesive was used to fix the components to the photomask substrate. Welding may be performed using metal or the like. Alternatively, it may be fused.

In addition, although this example has a structure in which the stage directly supports the photomask substrate, a structure in which the stage directly supports the photomask substrate may be adopted. However, in this case, the portion that supports the photomask substrate on the cassette naturally has the structure of the present invention.

In addition, if the acceleration of the stage exceeds the supporting force of the photomask substrate due to gravity and the photomask substrate shifts, there is a mechanism that presses the part directly above the sphere against the photomask substrate from above against the stage side with necessary and sufficient pressure. It is sufficient to have the following.

In addition, in this example, the height and inclination angle of the photomask substrate are fixed, but if necessary, it may be possible to create a structure in which the height of the bits, holes, and flat parts can be adjusted using piezoelectric drive elements, etc. It will be done.

Further, in this example, the ball is attached to the bottom of the photomask substrate, but it may be attached to the top and supported by being pushed up from the bottom of the photomask substrate.

〔Effect of the invention〕

As is clear from the above description, the present invention supports the photomask substrate by engaging a sphere or the like with the groove and the bit, so that even a small fixed pressure, which is similar to the force of gravity applied to the photomask substrate, can be applied to the photomask substrate during stage movement. If the acceleration is sufficiently small, the photomask substrate can be supported without shifting. Therefore, the distortion of the photomask substrate is reduced, and the accuracy of the drawing position in the exposure device and the coordinate measurement accuracy in the coordinate measuring device are improved.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, and FIGS.
Cross-sectional view taken along the V line and the V-■ line, Fig. 6~
11 is a cross-sectional view of a main part of another embodiment, FIG. 12 is a plan view of a conventional photomask substrate support device, and FIG. 13 is a plan view of a conventional photomask substrate support device.
The figure is a cross-sectional view taken along the xm-xm line in Fig. 12,
FIG. 14 is a plan view of another conventional photomask substrate support device, and FIG. 15 is a sectional view taken along the line xv-xv in FIG. 14. (1)...Photomask substrate, (2)...Stage, (
3a) to (3c)...Sphere (first, second, third support points), (5)...Bit, (6)...■Groove, (7)...Flat surface. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] In a photomask substrate support device that supports a photomask substrate substantially parallel to a flat stage, the distance between the photomask substrate and the stage is formed by engagement between a protrusion having an arcuate cross section and a recess. a first support point that is the center of the rotation axis of the photomask substrate, and a second support point that determines the rotation angle of the photomask substrate, which are arranged at two vertices of a virtual triangle, respectively; and a cross-sectional circle. a third support point formed by engagement between an arcuate protrusion and a flat surface, disposed at one other vertex of the virtual triangle, and regulating the inclination of the photomask substrate; Photomask substrate support device.