JPH03263046A - Pellicle for photomask - Google Patents

Abstract

PURPOSE:To allow the easy replacement of a pellicle film in a short period of time by separating a supporting frame to a photomask side and a pellicle film side and again integrating the supporting frame. CONSTITUTION:A projecting shape 3 of the supporting frame on the pellicle film side and the supporting frame which is the supporting frame on a tacky adhesive side and has a recessed shape 4 can be easily separated from and fitted to each other. Only the pellicle film 1 is separated and removed together with the supporting frame 3 on the pellicle film side without peeling the entire part of the pellicle from a photomask and in the state of holding the supporting frame on the photomask side adhered to the photomask when the exchange of the pellicle film 1 is necessary as dust sticks onto the pellicle film 1 or the pellicle film 1 is damaged or the pellicle film 1 is deteriorated. The brand new pellicle film 1 is thereafter integrated and mounted again in the part of the supporting frame 3. The peeling and exchanging of the pellicle film 1 are easily executed in a short period of time in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a pellicle for a photomask that is attached to a photomask used in the manufacture of semiconductor integrated circuits.

Conventional Technology Traditionally, in order to protect photomasks (collectively called photomasks, including reticles) from floating particles, dust, etc., pellicles, which are made of a metal support frame with an extremely thin film that allows exposure light to pass through, have been used. It is often used attached to a photomask. The structure of a conventionally used pellicle and its usage will be explained below.

FIG. 3 shows the cross-sectional shape of a typical pellicle, in which 12 is a pellicle membrane, 13 is an adhesive layer, 14 is a support frame, and 1
5 is an adhesive layer. Pellicle membranes often contain nitrocellulose, have a thickness of about 1 μm to several μm, and have a light transmittance of about 90% or more (usually about 98% or more) for exposure light. The adhesive layer is made of epoxy resin or the like, and adheres the pellicle membrane to the support frame. The support frame is often made of aluminum alloy, has a different shape depending on the type and model of the aligner, and has a height of several I. The adhesive layer is usually double-sided tape, and it not only adheres the velicle to the photomask, but also serves as a cushion when attached.

FIG. 4 shows the cross-sectional shape of a photomask and a pellicle after the pellicle having the structure described above is used.

Figure 4 shows a reduction projection exposure device (hereinafter referred to as stepper)
This figure shows the cross-sectional shape of a photomask (reticle) with pellicles attached to both sides. 24 is a photomask, 25 is a glass surface (back surface), and 26 is a pattern surface (front surface).

On the glass surface side, a support frame pellicle whose height is as low as the thickness of the photomask is used. 27 and 28 are garbage.

When attaching a pellicle to a photomask, the glass surface and pattern surface of the photomask are cleaned to completely remove dust transferred during exposure.

By attaching a pellicle to a photomask and using it in this way, the pattern surface of the photomask and the pellicle film are separated by the height of the support frame, which prevents dust and dirt from forming on the pellicle film. Even if 27.28 is attached,
If the size is several tens of μm or less, the image will not be transferred out of focus. Therefore, inspection of the photomask after the start of use can be reduced and cleaning is not necessary, which not only extends the life of the photomask, but also prevents a decrease in chip yield due to adhesion of dust.

Problems to be Solved by the Invention However, with conventional pellicles, if dust of a size that can be transferred onto the pellicle film (usually about 100 μm or more) adheres to the pellicle film, or if the pellicle film is damaged due to careless handling, etc. Or, when the photomask has been used for a long time and the membrane has deteriorated (end of life) and needs to be replaced, the entire pellicle must be peeled off from the photomask, the photomask must be cleaned, and then reattached. . When cleaning the photomask after removing the pellicle, it is not only necessary to find special cleaning conditions using detergent in order to remove the adhesive attached to the photomask, but it also takes a considerable amount of man-hours to complete the reattachment. The disadvantage is that it takes time. The present invention solves the above conventional problems,
The present invention provides a pellicle for a photomask that can be easily peeled off and replaced in a short time.

Means for Solving the Problems In order to achieve this object, the photomask pellicle of the present invention has a support frame with the support frame facing the photomask side (adhesive layer (111f)).
) and the pellicle membrane side, and has a structure that allows them to be integrated again.

Function: With a photomask pellicle having this structure, the entire pellicle can be peeled off from the photomask when dust adheres to the pellicle film, when the pellicle film is damaged, or when the pellicle film deteriorates and needs to be replaced. Without this, the support frame on the photomask side remains adhered to the photomask, and only the pellicle membrane can be separated and removed together with the support frame of the pellicle membrane example. Thereafter, a new pellicle membrane can be installed again by integrating it at the support frame.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows the cross-sectional shape of a pellicle for a photomask in one embodiment of the present invention. In FIG. 1, the convex support frame 3 of the pellicle membrane example and the concave support frame 4 of the adhesive layer side support frame have a structure that can be easily separated or fitted. Note that the shape and structure of the fitting portions of both support frames are arbitrary.

FIG. 2 shows a cross-sectional shape of a pellicle for a photomask in another embodiment of the present invention. In FIG. 2, 8 is a support frame for the pellicle membrane example, 10 is a support frame on the adhesive layer side, and 9 is an adhesive layer for bonding the two support frames. The two support frames can be separated at the adhesive layer and then integrated again.

As described above, according to the embodiment of the present invention, the support frame of the photomask pellicle can be separated into the photomask side and the pellicle membrane side, and can be integrated again.
When the pellicle membrane needs to be replaced, it can be easily replaced with a new one in a short time.

Effects of the Invention The present invention provides a pellicle for a photomask, which has a structure in which the support frame can be separated into the photomask side and the pellicle membrane side and integrated again, and the pellicle membrane can be easily replaced in a short time. It is possible to achieve this.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a pellicle for a photomask according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a pellicle for a photomask according to another embodiment of the present invention, and FIG. 3 is a cross-sectional view of a pellicle for a photomask according to another embodiment of the present invention. FIG. 4 is a cross-sectional view of a stepper reticle with pellicles attached to both sides. 1.6,12.16.20...Pellicle membrane, 2
．． 7, 9, 11, 13, 17.21... Adhesive layer, 3, 8... Support frame on the pellicle membrane side, 4, 10
・・・・・・Support frame on adhesive layer side, 5, 11.15.19
゜23...adhesive layer, 14,18.22...
...Support frame, 24...Photomask, 25...
...Glass side of photomask, 26...
Chrome pattern, 27.28... garbage.

Claims (2)

[Claims] (1) A pellicle membrane, a first support frame bonded via an adhesive layer along at least the outer periphery of the pellicle membrane, and a first support frame provided on the opposite side of the pellicle membrane bonding surface of the first support frame. A pellicle for a photomask, comprising a protrusion, a second support frame having a recess coupled to the protrusion, and an adhesive layer provided on the opposite side of the recess of the second support frame. (2) The photomask according to claim 1, wherein the first support frame and the second support frame are coupled through an adhesive layer between them. Pericles.