JPH06273921A - Mask protecting pellicle - Google Patents

Abstract

PURPOSE:To prevent the deformation of the pellicle due to the variation of atmospheric pressure outside the pellicle and to enhance the reliability by making the pellicle permeable to air. CONSTITUTION:One or plural holes 14 are provided at a part of a pellicle 12 to make the pellicle 12 permeable to air. The diameter of the hole is not necessarily limited but preferably controlled to <=1mum to prevent the intrusion of dust, etc. Meanwhile, the hole 14 should be provided not to affect pattern transfer. Since the pellicle 12 is permeable to air, the pellicle is not deformed by the variation of atmospheric pressure outside the pellicle. Further, a filter may be furnished on the lower part of the pellicle to prevent the intrusion of dust, etc., a circular frame can be used instead of the rectangular frame, and the pellicle itself can be made of an air-permeable material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pellicle for mask protection used in a photolithography process in the manufacturing process of semiconductor devices.

[0002]

2. Description of the Related Art A semiconductor device manufacturing process requires a photolithography process for forming a pattern by transferring a pattern of a photomask onto a semiconductor wafer. If foreign matter such as dust adheres to the pattern surface of the photomask in this step, it is also transferred to the wafer, pattern defects occur, and as a result, the manufacturing yield of semiconductor devices decreases.
In order to prevent such a situation, conventionally, a mask protection pellicle has been used.

FIG. 2 is a perspective view schematically showing a conventional mask protecting pellicle, in which 21 is a pellicle frame, 22 is a pellicle film, and 23 is a photomask. On the upper surface of the pellicle frame 21, a translucent pellicle film 22 is stretched with an adhesive. An adhesive is also applied to the lower surface of the pellicle frame, and the pellicle frame is mounted on the photomask.

[0004]

As shown in FIG. 2, in the conventional mask protecting pellicle, the pellicle film 22 becomes convex or concave depending on the fluctuation of the atmospheric pressure outside the pellicle. There is a problem in that the convex pellicle film 22 may be damaged or broken by touching the case of the photomask, and the pellicle's original function of preventing adhesion of dust or the like to the pattern surface of the photomask may not be fulfilled.

An object of the present invention is to provide a highly reliable mask protecting pellicle which prevents a change in shape of the pellicle film due to a change in atmospheric pressure outside the pellicle.

[0006]

The pellicle for mask protection according to the present invention is characterized in that the pellicle film has air permeability.

[0007]

1 is a perspective view schematically showing a mask protecting pellicle according to an embodiment.

Pellicle film 12 on pellicle frame 11
The method of installing the photomask 13 and the photomask 13 is the same as that of the conventional example.

The present embodiment is different from the conventional example of FIG. 2 in that one or more holes 14 are provided in a part of the pellicle film 12 so that the pellicle film 12 has air permeability. Here, the diameter of the hole 14 is not particularly limited, but is preferably 1 μm or less in order to prevent intrusion of dust and the like. Further, the place where the hole 14 is provided is preferably a place which does not affect the pattern transfer.

As described above, since the pellicle film 12 has air permeability, there is no change in the shape of the pellicle film 12 due to fluctuations in atmospheric pressure outside the pellicle.

In the above embodiment, a filter may be further provided in contact with the lower part of the pellicle film in order to prevent dust and the like from entering from the outside of the pellicle.

Further, although the rectangular frame is used in the above embodiment, the invention is not limited to this, and it may have a circular shape or another shape.

Further, although the pellicle film is provided with holes in the above embodiment, the same effect can be obtained even if the pellicle film itself is made of a gas permeable material.

[0014]

According to the present invention, since the pellicle film has air permeability, it is possible to prevent the shape change of the pellicle film due to the fluctuation of the atmospheric pressure outside the pellicle, and to provide a highly reliable mask protecting pellicle.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a mask protecting pellicle according to an embodiment of the present invention.

FIG. 2 is a perspective view schematically showing a conventional example.

[Explanation of symbols]

 12 ... Pellicle membrane

Claims (1)

[Claims] 1. A pellicle for mask protection, wherein the pellicle film has air permeability.