JPH03138649A - Pellicle - Google Patents

Abstract

PURPOSE:To simplify an operation to exchange the pellicle and to eliminate the defect by the damage of a mask during an exchange operation by providing a frame body with an opening part smaller than the outside shape of the mask and a step larger than the outside shape of the mask over the entire periphery from the aperture on the rear surface of the frame body and applying a tacky adhesive on the rear surface of the frame body excluding the step. CONSTITUTION:The frame body 11 is provided with the opening part 11a smaller than the outside shape of the mask 14 and is provided with the step 11b larger than the outside shape of the mask 14 over the entire periphery from the aperture 11a on the rear surface of the frame body 11. The tacky adhesive 13 is applied on the rear surface of the frame body 11 exclusive of the step 11b. The mask 14 is held so as to be held therebetween by the step 11b provided on the frame body 11 of the pellicle 10 in such a manner and, therefore, the tacky adhesive 13 of the pellicle 10 is not applied at all on the mask 14. The mask 14 is easily removed from the frame body 11 in such a manner and the defective mask caused by damaging the costly mask 14 is obviated during the operation to exchange the pellicle 10.

Description

[Detailed Description of the Invention] [Summary] Regarding a pellicle that protects both sides of a mask by spreading a light-transmitting film on the surface of a frame, the present invention simplifies the pellicle replacement work and prevents defects due to damage to the mask during the replacement work. Aiming to provide a pellicle that can reduce the frequency of replacement as well as waste, a transparent film is spread on the surface of the frame to protect both sides of the mask, which has a light-blocking pattern on a transparent substrate. In the pellicle, the frame has an opening smaller than the outer shape of the mask, and has a step larger than the mask outer shape on the entire circumference from the opening on the back side of the frame, and the back side of the frame except for the step has an opening smaller than the outside of the mask. Configure by applying adhesive.

[Industrial application field]

The present invention provides a pellicle that protects both sides of the mask by spreading a light-transmitting film on the surface of the frame, and in particular, simplifies the pellicle replacement work, eliminates defects caused by damage to the mask during the replacement work, and reduces the frequency of replacement. Regarding the pellicle that can be

The pattern width of recent large-scale, highly integrated semiconductor devices [
Yo, 4M DRAM (DRAM; Dyn
amic Random Access Memory:
Read/write memory that requires memory retention operation)
It is in the submicron range, as typified by .

Therefore, in handling the mask, it is essential to prevent foreign matter such as dust and oil mist from attaching to the mask, which may cause pattern defects, and to avoid scratches on the mask.

For this reason, a method of attaching pellicles to both sides of the mask and protecting the mask with the pellicle has been widely adopted.

[Conventional technology]

Next, a conventional pellicle will be described in detail with reference to the drawings.

Figure 2 is an explanatory diagram of a conventional pellicle, in which (a) is a plan view of the pellicle, (b) is a side sectional view of the pellicle, and (c) is a side sectional view of the mask to which the pellicle is attached. It is a diagram.

The conventional pellicle 20 was composed of a frame 21, a transparent film 22, and an adhesive 23.

The frame 21 is formed by providing a square or rectangular opening 21a inside a square or rectangular aluminum alloy flat plate smaller than the outer diameter of the mask 24.

A conventional pellicle is constructed by spreading a light-transmitting film 22 on the surface of a frame 21 with such structural dimensions via an adhesive 25, and applying an adhesive 23 on the back surface (as shown in the figure). (a) and (b) of the same figure).

Then, the pellicle 20 is attached to both sides of the mask 240 via the adhesive 25.

In this way, the mask 24 is isolated from the outside by the pellicle 20, and is protected from adhesion of foreign matter and mechanical damage, ie, scratches (see FIG. 2(c)).

[Problems to be Solved by the Invention] The mask 24 to which the pellicle 20 is attached is protected from adhesion of foreign matter and damage such as scratches.

However, the transparent film 22 of the pellicle 20 will naturally have foreign matter attached to it or scratches.

When performing exposure work using the mask 24 to which the pellicle 20 is attached, the pattern of the mask 24 is focused on the object to be exposed (not shown), so foreign matter or scratches attached to the transparent film 22 are removed. There is no problem if the scratches are small.

However, the mask 24 with the pellicle 20 attached,
Generally, it is used frequently and is attached to and detached from an exposure apparatus (not shown) many times.

Therefore, in reality, it is inevitable that large foreign objects will adhere to the light-transmitting film 22 of the pellicle 20 or that large scratches will occur.

Therefore, it becomes necessary to replace the pellicle 20 (replace the pellicle 20).

However, since the adhesive 23 of the pellicle 20 adheres to the mask 24 with strong adhesive force, peeling the pellicle 20 from the mask 24 is a very troublesome and time-consuming task.

Furthermore, during this replacement work, the surface of the mask 24 was rarely damaged and the expensive mask 24 was rendered defective.

Furthermore, since the frame 21 of the pellicle 20 was smaller than the mask 24, the entire pellicle 20 was irradiated with ultraviolet light from the exposure device.

For this reason, the chemically unstable adhesive 23 deteriorates and becomes brittle, becoming granular foreign matter that adheres to the surface of the mask 24, and this foreign matter may be transferred and make the exposed object defective. It wasn't much.

The present invention was made to solve this problem, and its purpose is to simplify the belt replacement work, eliminate defects caused by damage to the mask during the replacement work, and reduce the frequency of replacement. The goal is to provide a pellicle that can

[Means for Solving the Problems] The object is to provide a mask 14 in which a light-transmitting film 12 is spread on the surface of a frame 11 and a light-blocking pattern is provided on a light-transmitting substrate, as shown in FIG. In the pellicle 10 that protects both sides of the mask 14, the frame 11 has an opening 11 smaller than the outer shape of the mask 14.
a, and has a paragraph 11b larger than the outer shape of the mask 14 on the entire circumference from the opening 11a on the back surface of the frame 11, excluding the paragraph 11b (adhesive 13 is applied to the back surface of the frame 11). This can be achieved by using a pellicle that is characterized by:

[For production]

The mask 14 includes a paragraph 1 provided on the frame 11 of the pellicle 10.
It is held in such a way that it is sandwiched between the two parts 1b.

Therefore, since the adhesive 13 of the pellicle 10 is not attached to the mask 14 at all, the mask 14 can be removed from the frame 11 very easily.

As a result, during the replacement work of the pellicle 10, the expensive mask 14 is not damaged and becomes defective.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory view of a pellicle according to an embodiment of the present invention, in which (a) is a side sectional view of the pellicle, (b) is a back view of the pellicle, and (b) is a back view of the pellicle.
Figure (c) is a side sectional view of a mask to which a pellicle is attached.

A pellicle 10 according to an embodiment of the present invention has an external dimension of 127 m in width.
It is intended for a mask 14 with a length of 127 mm and a thickness of 2.3 mm, and includes a frame 11, a transparent film 12, and an adhesive 13.
It is composed of

The frame body 11 is 137 mm wide, 1137 mm wide, and 7.5 mm thick.
133mm wide inside the aluminum alloy flat plate
, an opening 11a with a length of 133 mm is provided, and the back surface from the opening 11a is 1.2 mm deep.
, and is formed by providing a paragraph 11b with a width of 2.3 mm.

A transparent film 12 made of nitrocellulose with a thickness of 2.85 μm is spread on the surface of the frame 11 having such structural dimensions via an adhesive 15, and a butyl rubber is coated on the back surface of the frame 11 except for the section 11b. An embodiment of the pellicle of the present invention is completed by applying an adhesive 13 of adhesive type (acrylic type is also acceptable) (see figure (a)
) and figure (b)).

Next, one method for attaching the pellicle 10 to the mask 14 will be explained in order of steps.

Note that the work of attaching the pellicle 10 to the mask 14 is normally performed in a clean bench located in a clean room.

First, since the pellicle 10 is attached to protect both sides of the mask 14, two pellicles 10 are prepared.

Then, one pellicle 10 is placed in a predetermined mounting jig (not shown) with the transparent film 12 facing downward.

Naturally, in this state, the width 123.3 mm, the length 123.3 mm, and the depth 1.2 m provided on the back surface of the pellicle 10 are
The paragraph 11b of m is facing upward.

Next, in this paragraph 11b, a width of 123 mm and a length of 123 m are added.
After attaching a mask 14 having a thickness of 2.3 mm and a thickness of 2.3 mm, the adhesive 13 of another pellicle 10 is made to adhere to the adhesive 13 of the other pellicle 10 with the back surface facing downward.

Thus, the work of attaching the pellicle 10 to the mask 14 is completed, and the entire mask 14 is isolated from the outside by the pellicle 10, and is protected from adhesion of foreign matter to the mask 14 and scratches. (See figure (c)).

As described above, the pellicle 10 of the present invention includes the adhesive 13.
The structure is such that it does not adhere to the mask 14 at all.

Therefore, the compensation during use of the transparent film 12 of the pellicle 10,
In addition, the pellicle 10, which must be replaced due to deterioration due to repeated irradiation with ultraviolet rays (the transparent film becomes cloudy and the light transmittance decreases), is extremely simple and easy to replace during the replacement process compared to conventional pellicles. This eliminates the need to damage the mask 14 and make it defective, resulting in a great advantage.

Furthermore, the adhesive 13 of the pellicle IO is applied to the back surface of the frame 11 of the pellicle 10, which corresponds to the outer side of the outer periphery of the mask 14.

As a result, when used in an exposure device (not shown), it moves away from the ultraviolet rays generated by the exposure device.
The direct irradiation of the ultraviolet rays is hardened, and the influence of the ultraviolet rays that propagate toward the outer periphery while being reflected inside the mask 14 is also eliminated, and the deterioration of the adhesive 13 due to ultraviolet rays is eliminated, and the pellicle 1
The frequency of 0 exchange will be significantly reduced.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, replacing the pellicle attached to a mask is not only extremely simple compared to conventional pellicles, but also eliminates defects caused by expensive damage to the mask during pellicle replacement. becomes possible.

In addition, deterioration of the adhesive used in the pellicle is prevented by ultraviolet light.

Therefore, there is no need to replace the pellicle due to deterioration of the adhesive, making it possible to reduce the frequency of replacing the pellicle.

14 is a mask, 15 each indicates an adhesive.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a pellicle according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of a conventional pellicle. In the figure, 10 is Verital, 11 is the frame, 12 is the transparent film, 13 is the adhesive, (0) Pellicle L near) key (b) Palnocle a > Inkstone Jrtfm (b) Bevel ■ 1st view of Shino (C) Pada ■ 11th reading r; Mask's stubbornness #r side map I 2nd view of Berig 2 Shino e circle map 2nd map Sinkyo

Claims (1)

[Claims] A mask (14) in which a light-transmitting film (12) is spread on the surface of a frame (11) and a light-blocking pattern is provided on a light-transmitting substrate.
In a pellicle (10) that protects both sides of the frame (11), the frame (11) has an opening (11a) smaller than the outer shape of the mask (14), and an opening (11a) on the back side of the frame (11). It has a paragraph (11b) larger than the outer shape of the mask (14) around the entire circumference of the frame, and an adhesive (13) is applied to the back side of the frame (11) except for the paragraph (11b). Pericles to do.