Container for storing a pellicle for lithography

Abstract

There is provided a pellicle container for storing a pellicle used in lithography, having a tray and a cover between which the pellicle is stored, and the tray has a pellicle mount section on which the pellicle is used to be mounted, but the tray of this container further has a plane plate, preferably a quartz plane plate, having a flatness of 10 micrometers or smaller provided on top of the pellicle mount so as to stabilize the flatness of the pellicle, especially its agglutinant layer.

Claims

1. A pellicle storing apparatus, comprising: a pellicle comprising: a pellicle frame, and a transparent pellicle membrane attached to an upper side of the pellicle frame, wherein the pellicle frame having an agglutinant layer attached on a lower side of the pellicle frame, the agglutinant layer being covered with a protective separator; and a tray comprising: a plate made of quartz, and a pellicle mount made of a resin, the pellicle mount having a square surface and the plate made of quartz being placed on the square surface, wherein the agglutinant layer covered with the protective separator is placed directly on a surface of the plate, the surface of the plate having a flatness of 10 micrometers or smaller.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 This is a schematic drawing of an assembly of the present invention including a tray and a pellicle mounted on it.

(2) FIG. 2 This includes a plan view and a side view of a tray of a pellicle container of the present invention, and an A-A cross section thereof.

(3) FIG. 3 This is a schematic drawing of a tray of a conventional pellicle container with a pellicle mounted on it.

(4) FIG. 4 This includes a plan view and a side view of a tray of a conventional pellicle container, and an A-A cross section thereof.

(5) FIG. 5 This is a graph showing ups and downs measured of the pellicle mount of the tray of a pellicle container of the present invention.

(6) FIG. 6 This is a graph showing ups and downs measured of the pellicle mount of the tray of a conventional pellicle container.

EXAMPLES TO EMBODY THE INVENTION

(7) Now, examples and a comparative example relative to the present invention will be described with reference to the drawings attached, but the present invention shall not be confined to the examples. The present invention is characteristic in that a plane plate, preferably a quartz plane plate 7, having a flatness of 10 micrometers or smaller is introduced, and except for this the construction of the pellicle container of the present invention is similar to that of conventional pellicle containers.

(8) Also, in the examples of the present invention the quartz plane plate 7 is used, and since a plane plate made of quartz is hard and durable and its surface can be easily polished to have a flatness of 10 micrometers or smaller and such flatness of quartz plate can be preserved for a long time, use of a quartz plane plate is most recommended.

EXAMPLES

Example 1

(9) In Example 1, as shown in FIG. 2, a tray of a square pellicle container 1 made of polycarbonate and having an external measure of 200 mm by 200 mm was manufactured by mold injection. Also, a quartz plane plate 7 measuring 150 mm by 116 mm by 6.35 mm (in thickness) was provided on top of a pellicle mount 6, which was in the middle of the tray. The flatness of this quartz plane plate 7 was 7 micrometers.

(10) Next, as shown in FIG. 1, a pellicle was let to sit alone for a predetermined period of time on the surface 8 of the quartz plane plate 7 with the agglutinant layer 4 covered with its protective separator film 5 lying directly on the quartz plane plate 7. Then, the pellicle was removed from this pellicle container 1 and the flatness of the surface of the agglutinant layer 4 was measured and it was found that the value of the flatness had changed by only 10 micrometers during the sitting. Also, this pellicle was adhered to a mask via the agglutinant layer, and the mask was scarcely deformed by the pellicle.

Example 2

(11) Also, in Example 2, similarly as in Example 1, a polycarbonate tray of a pellicle container was used, and on the middle of it was provided a quartz plane plate 7 measuring 150 mm by 116 mm by 6.35 mm (in thickness) and having a flatness of 10 micrometers. Then, a pellicle was let to sit alone for a predetermined period of time on the quartz plane plate 7 with the agglutinant layer 4 covered with the separator film 5 lying directly on the quartz plane plate 7. Then, the pellicle was removed from this pellicle container and the flatness of the surface of the agglutinant layer 4 was measured and it was found that the value of the flatness had changed by only 12 micrometers during the sitting. Also, this pellicle was adhered to a mask via the agglutinant layer, and the mask was scarcely deformed by the pellicle.

COMPARATIVE EXAMPLE

Comparative Example 1

(12) In Comparative Example 1, as shown in FIG. 4, a tray of a square pellicle container 1 made of polycarbonate and having an external measure of 200 mm by 200 mm was manufactured by mold injection. The pellicle mount 6 in the middle of the tray was measured for its flatness, and as is read from the graph of FIG. 6, the maximum height was about 80 micrometers, which means the flatness of the pellicle mount 6 was bad.

(13) Next, as shown in FIG. 3, a pellicle was let to sit alone for a predetermined period of time on the pellicle mount 6 with the agglutinant layer 4 covered with its protective separator film 5 lying directly on the pellicle mount 6. Then, the pellicle was removed from this pellicle container 1 and the flatness of the surface of the agglutinant layer 4 was measured and it was found that the value of the flatness had changed by 30 micrometers during the sitting. Also, this pellicle was adhered to a mask via the agglutinant layer, and the mask underwent a substantial deformation induced by the pellicle.

EXPLANATION OF REFERENCE NUMERALS

(14) 1: pellicle container 2: pellicle membrane 3: pellicle frame 4: agglutinant layer 5: separator 6: pellicle mount 7: quartz plane plate 8: surface of quartz plane plate