JPS62270959A - Mask frame - Google Patents

Abstract

PURPOSE:To use a small mask against a batch projection exposing device using the mask of a large screen, and to increase the generality of the exposing device, by attaching one or plural masks to one of frame plate whose shape is larger enough then each mask, and forming them integrally as one piece of mask frame. CONSTITUTION:Four masks 1 on which a pattern to be transferred is formed are attached to a frame plate 4 and constitutes a mask frame 20, and the frame plate 4 is formed by a metal or ceramics. When an illuminating light 16 is brought to slit projection as indicated with an arrow (f) from a light source, a projection optical system 13 leads a light beam irradiating the mask 1, onto a substrate 10 and forms a pattern 17. the mask frame 20 can move as indicated with arrows (g), (h) in the X direction and the Y direction, respectively, and four pieces of divided masks 1 are successively moved to an exposure position. When the alignment is being adjusted, the illuminating light 16 is obstructed by a shutter 11. When four pieces of masks 1 are successively moved to the exposure position and the mask and the substrate 10 are linearly scanned in the (i) direction, one large pattern 17 is synthesized on the substrate 10, and transferred and formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to an exposure apparatus used in a semiconductor manufacturing process or a liquid crystal device manufacturing process, and particularly relates to a mask frame for pattern printing.

[Background of the Invention] In a semiconductor lithography process, a pattern is transferred by exposing a substrate such as a sea urchin to light through an original plate such as a mask or reticle on which a pattern is formed (hereinafter referred to as a mask in this specification). . As the exposure apparatus, a contact exposure method, a proximity exposure method, a reflection type, a reduction projection exposure method, etc. are used. In a reduction projection exposure apparatus, a large mask is used in accordance with the magnification for reducing and projecting the mask using an optical system. A large mask is also used when patterning a large-screen liquid crystal display substrate by batch projection exposure. The mask is attached to a mask frame and mounted on an exposure device.

[Prior Art] In order to prevent scratches and stains during handling and to effectively expand the pattern formation area, a conventional mask is attached to a single mask frame. Therefore, in a projection exposure apparatus that uses a large mask, a small mask cannot be used, and versatility is limited.

[Object of the Invention] The present invention has been made in view of the drawbacks of the prior art, and it is possible to attach a small mask to a large-screen batch projection exposure apparatus, and also to make it possible to attach a plurality of masks to a projection exposure apparatus at the same time. The purpose of the present invention is to provide a mask frame that enables divisional exposure of a pattern.

[Example] FIG. 1 is a plan view of a mask frame according to the present invention.

Four masks 1 on which patterns to be transferred (not shown) are formed are attached to a frame plate 4 to constitute a mask frame 20. The frame plate 4 is made of metal or ceramic. FIG. 2 is a plan view of another embodiment, showing masks 1, 2, . ．． 3 are attached to the same frame plate 4.

FIG. 3 shows an example in which a small mask 1 is attached to a large frame plate 4, and the small-shaped mask can be used in an exposure apparatus for large-screen exposure. FIG. 4 shows an example of a mask frame 20 to which a plurality of masks 1 are attached, in which masks other than the mask to be used are covered with a light shielding plate 12. Each light shielding plate 12 has a screw 7
is fixed to the frame plate 4.

Examples of the structure for attaching the mask to the frame plate 4 are shown in FIGS. 5 to 7. An opening 14 is formed in the frame plate 4 at the mask mounting position. In the example shown in FIG. 5, the mask 1 is attached from the bottom side of the opening 14, and a presser plate 5 is provided on the bottom side of the mask 1, so that the peripheral edge of the mask 1 is attached to the upper protrusion 14 of the opening 14.
It is held between a and the lower pressing plate 5. The presser plate 5 is fixed to the lower surface of the frame plate 4 with screws 7. A push screw 6 for adjusting the position of the mask 1 is provided on the upper edge 14a and side surface of the opening 14. The mask 1 is mounted on the frame plate 4 on the tray 8 so that the pattern forming surface (lower surface) a of the mask 1 is on the same plane as the stage mounting reference surface on the lower surface of the frame plate 4. mask frame 20
is fixedly held on the mask stage 8. Thereby, the pattern forming surface a of the mask 1 is aligned at a predetermined position.

FIG. 6 shows another example of the mounting structure for the mask 1. In this example, the mask 1 is bonded to the side surface of the opening 14 of the frame plate 4 with an adhesive 15. In this example as well, the pattern forming surface a of the mask 1 is the same surface as the stage mounting reference surface of the frame plate 4, as in the example of FIG.

FIG. 7 shows yet another example of the mounting structure of the mask 1. In this example, the mask 1 is mounted and supported on the periphery of the upper surface of the opening 14 of the frame plate 4, and is fixedly held on the frame plate 4 by a fixture 9 using screws 7. In this example, the pattern forming surface a of the mask 1 is the same as the upper surface d of the frame plate 4, and the thickness of the frame plate 4 is determined so that this upper surface d is separated by a predetermined distance from the reference surface for mounting the stage. It is being As a result, when the mask frame 20 is mounted on the mask stage, the pattern forming area a of the mask is aligned with the desired position. FIG. 8 shows an example of the use of the mask frame according to the present invention. The four masks 1, which are obtained by dividing the pattern 17 to be formed into four parts, are attached to the frame plate 4.
It is attached to the mask frame 20 of one plate. Illumination light 16 is emitted from a light source (not shown) into the slit as indicated by an arrow f. 11 is a light shielding plate (shutter);
It is movable to irradiate the mask 1 after mask alignment. Reference numeral 13 denotes a projection optical system, which guides the light irradiated onto the mask 1 onto the substrate 10 to form a pattern 17. The mask frame 20 is movable in the X and Y directions as indicated by arrows g and h by an alignment mechanism (not shown), and sequentially moves the four divided masks 1 to the exposure position. During alignment adjustment, the illumination light 16 is blocked by the shutter 11. By sequentially moving the four masks 1 to the exposure position and linearly scanning the masks 1 and the substrate 10 in the i direction, one large pattern 1 is formed on the substrate 10.
7 is synthesized and transferred.

Note that the outer shape of the frame plate of the mask frame can be any shape in consideration of ease of handling and the like.

Further, each mask may be provided with a pellicle for pattern protection. Pellicles may be provided for multiple masks at once. Further, instead of the mask position adjustment push screw in the embodiment shown in FIG. 5, a spring may be used to press the mask in a certain direction for positioning.

[Effects of the Invention] As explained above, the mask frame according to the present invention has the following effects:
One or more masks are attached to a single frame plate that is sufficiently large compared to each mask, and are integrated as a single mask frame, so it is possible to use a small mask in contrast to a batch projection exposure system that uses large-screen masks. This increases the versatility of the exposure apparatus. Also, multiple masks can be printed on a single wafer at the same time. Further, by sequentially exposing a plurality of masks, a large pattern can be formed by combining them, and a large pattern can be easily formed using divided masks.

[Brief explanation of drawings]

1 to 4 are plan views of different embodiments of the mask frame according to the present invention, and FIGS. 5 to 7 are cross-sectional views of the mask frame showing different examples of the mask mounting structure. FIG. 8 is an explanatory diagram of an example of use of the mask frame according to the present invention. 1.2, 3: Mask, 4: Frame plate, 8: Mask stage, 14: Opening. Patent Applicant Canon Co., Ltd. Agent Patent Attorney Tatsuo Ito Agent Patent Attorney Satoshi Ito Kozutsu 1v! J Figure 2 Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. One or more masks formed in a shape that can be attached to a mounting portion for mounting an exposure mask of a substantially specific shape, and to which an exposure mask of an arbitrary shape smaller than the mask is mounted. An exposure mask frame comprising a frame plate having an opening. 2. A mask holding protrusion is formed on the upper side of the frame plate of the opening, a mask holding presser plate is provided on the lower side of the frame plate of the opening, and a mask peripheral edge is formed between the protruding edge and the presser plate. 2. The mask frame according to claim 1, wherein the mask frame is sandwiched between the mask frames. 3. The mask frame according to claim 2, characterized in that push screws for adjusting the position of the mask are provided on the projecting edges and side edges of each of the openings. 4. The mask frame according to claim 2, wherein a pressing spring for positioning the mask is provided on the projecting edge and side edge of each of the openings. 5. The mask frame according to claim 1, wherein the mask is bonded to the side surface of the opening via an adhesive. 6. The mask frame according to claim 1, wherein the lower surface of the mask is flush with a reference surface for mounting a stage on the lower surface of the frame plate. 7. The mask frame according to claim 1, wherein the mask is supported on the periphery of the opening, mounted on the upper surface of the frame plate, and fixed onto the frame plate by a presser member. 8. The mask according to claim 7, wherein the thickness of the frame plate is determined such that the lower surface of the mask is spaced by a predetermined distance from a reference surface for mounting a stage on the lower surface of the frame plate. flame. 9. The mask frame according to claim 1, wherein the frame plate is made of metal. 10. The mask frame according to claim 1, wherein the frame plate is made of ceramic.