JP3377735B2 - Method of cutting thin film in method of manufacturing mask protection device, and cutting jig used in the method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for the purpose of preventing dust and the like from adhering to a mask or reticle (hereinafter referred to as "mask") used in a photolithography process in a manufacturing process of an integrated circuit. In a method of manufacturing a mask protection device comprising a pellicle frame having a size enclosing a pattern and a transparent thin film stretched on one end surface of the frame, after bonding the thin film to the one end surface of the pellicle frame, The present invention relates to a method of cutting a thin film protruding from an edge and a cutting jig used in the method.

[0002]

2. Description of the Related Art A mask protection device is usually a spin coating method,
An organic thin film such as nitrocellulose or ethyl cellulose formed on a glass substrate by a pulling method such as immersing in a solution and pulling it up, as shown in FIG.
The thin film 3 protruding from the edge of the pellicle frame 1 is first attached to a temporary frame 2 having a larger size, and then the temporary frame 2 is pushed down to one end surface of the pellicle frame 1 to which an adhesive has been applied so that the thin film 3 protrudes from the edge of the pellicle frame 1. Obtained by cutting.

The thin film 3 can be cut by a cutting blade, a laser beam, a heat, or the like, but most of them are cut by an organic solvent, that is, as shown in the figure. A method is used in which the tip of an injection needle-shaped jig 5 is pierced into the thin film 3 and the organic solvent that dissolves the organic thin film 3 is released from the jig tip while moving along the outer edge of the frame. (Japanese Patent Publication No. 7-57528), however, by dissolving a polymer compatible with the thin film in an organic solvent capable of dissolving the thin film, a solution in which the solubility of the thin film is controlled is dropped by using a dispenser. A method of dissolving and cutting an unnecessary film and a method of cutting the surface with a cutting blade and then dissolving the cut surface with the above solution to smooth the cut surface have been proposed (JP-A-7-281421). ).

[0004]

The above-mentioned method of cutting with an organic solvent requires a film-dissolving time, so that the film-cutting speed cannot be increased, and the thin film is not soluble in the organic solvent or is not compatible with the organic solvent. If the solubility is very low, it cannot be used. In this respect, for example, cutting with a physical cutting means such as a cutting blade does not require a film dissolving time like cutting with a solvent, so that the film cutting speed can be increased, work efficiency can be improved, and insoluble in an organic solvent. However, like other cutting methods, the chips attached to the cutting end surface may fall off when attached to the mask, which may cause dust generation. In order to deal with this problem, the cutting end face is wiped with a solvent for finishing, and it has been attempted to remove chips using a double-sided adhesive tape, but after cutting, a finishing process of the cutting end face and a chip removing process are required, It was also difficult to completely remove the chips.

An object of the present invention is to provide a method for cutting a thin film that does not generate chips that cause dust generation, and a cutting jig used in the method.

[0006]

SUMMARY OF THE INVENTION Therefore, according to the present invention, in a thin film cutting method of bonding a thin film to one end face of a pellicle frame and then cutting the thin film protruding from the outer edge of the frame by a physical cutting device, the physical cutting device is used. It is characterized in that the coating liquid is directly discharged to the cutting portion from an applicator attached to or incorporated in the physical cutting means prior to the cutting so as to apply the coating liquid.

The coating liquid used in the above invention must completely cover the cut end face of the thin film, suppress dust generation during cutting by the physical cutting means, and do not separate from the thin film. An example of such a material is a resin dissolved in an organic solvent. Examples of the resin include cellulose derivatives, silicone resins, epoxy resins, acrylic resins, fluorine-containing resins, and the like, and examples of the cellulose derivatives include nitrocellulose and cellulose propionate. it can. Specific examples of the fluorine-containing resin include C manufactured by Asahi Glass Co., Ltd.
Examples are YTOP (trade name) and Teflon AF (trade name). In any case, the coating material (resin) is preferably the same as or similar to the thin film material.

Examples of the organic solvent include fluorocarbon CT-100 (trade name) manufactured by Asahi Glass Co., Ltd.,
CT-130 (trade name), CT-160 (trade name), C
T-180 (trade name), EF manufactured by Tochem Products
-L102 (product name), EF-L155 (product name), E
F-L174 (trade name), EF-L215 (trade name),
IL-260 (trade name) manufactured by Tokuyama Corporation, IL-
263 (trade name) and the like can be illustrated.

Examples of the organic solvent include ketone type solvents such as methyl ethyl ketone, methyl isobutyl ketone and acetone, and lower fatty acid esters such as butyl acetate and isobutyl acetate, and a mixed solvent of ketone or ester and isopropyl alkole. It can also be used. The use ratio of the coating material to the organic solvent is usually 1 part by weight or more based on 100 parts by weight of the organic solvent.

The preferred coating liquid used in the present invention is a saturated solution in which the above resin is saturated and dissolved in the above organic solvent. As a method for preparing this saturated solution,
For example, the resin is usually immersed in the solvent at 20 to 25 ° C. for 12 hours or more. The longer the immersion time, the better, but for economic reasons it depends on the resin, but if it is 5 to 6 hours, it may be regarded as a substantially saturated solution. When such a coating liquid is used, the thin film is cut only by a physical cutting means such as a cutting blade, the thin film is not cut by a solvent, and the resin is dissolved in the coating liquid even if the thin film cutting speed is increased. Can be surely covered, and the finish is clean and no dust is generated.

The applicator used in the above invention may be any applicator capable of applying the coating liquid prior to cutting, and may be any device, but preferably a pipe-shaped coating liquid supply device. The coating liquid supplied from is discharged from the end of the pipe. The pipe-like structure has a simple structure and is not bulky, and can be easily attached to the cutting blade. Moreover, the applicator is attached to the physical droplet cutting means, and is operated integrally with the physical cutting means,
Physical means such as a cutting blade are integrally formed with the applicator. By adding the applicator to the physical cutting means, a device for moving the applicator, for example, a robot is not required , and only one device for moving the physical cutting means is sufficient. The structure is further simplified by integrally forming the objective means with the applicator.

In any case, the above-mentioned applicator applies the coating liquid to the cutting point prior to the cutting by the physical cutting means such as a cutting blade. This has the advantages of suppressing dust generation and increasing the cutting speed as compared to after cutting. As the physical cutting blade means used in the present invention, for example, a cutting blade can be mentioned as a preferable example, but in addition to this, as shown in FIG. 5, the tip portion of the pipe is squeezed to form a needle-shaped portion having a blade, Directly above the blade, three places to the left and right of it, a cutting jig with a coating liquid discharge port, and the tip of the pipe is formed into a needle shape as shown in Fig. 7, and there are four places just above and behind it. It is possible to use a cutting jig having a coating liquid discharge port formed therein. The cutting blade shown in FIG. 5 cuts the thin film along the edge of the frame by cutting the cutting edge 90 times each time it reaches the corner of the frame.
° Whereas it is necessary to change the direction, when the cutting blade is needle-shaped and the coating solution discharge ports are provided at four positions in the front, rear, left and right as shown in Fig. 7 , it is necessary to change the direction even when the corner of the frame is reached. There is no need to rotate the cutting jig.

When a physical cutting means having a blade is used like a cutting jig such as a cutting blade or a needle-shaped part having a blade, good cutting is possible, and it is possible to cut even if the cutting speed is increased. There is. When a cutting blade is used, the cutting blade may be of any type as long as it can cut a thin film along the edge of the frame, and regardless of its type, a thin blade with good sharpness is preferable. These include, for example, Olfa's single-edged (brand name "Matt Cutter"), Orfa's double-edged (brand name "Design Knife", "Circular Blade"), Feather's double-edged (brand name "Surgical Bloodies") Etc. can be illustrated.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 3 and 4, a cutting blade 1
1, a small-diameter pipe 12 connected to a coating liquid supply device (not shown) is attached, and the coating liquid discharge port 12a at the lower end cuts the thin film 14 protruding from the edge of the pellicle frame 13 by the cutting blade 11. Sometimes the coating liquid is located on the upper portion of the thin film, and the coating liquid is discharged from the discharge port 12a in a constant amount prior to the cutting by the cutting blade, and the coating liquid 16 is applied along the edge of the frame.
While applying, the cutting blade 11 is moved in the direction of the arrow at a constant speed for cutting.

The cutting jig 21 shown in FIGS. 5 and 6 is formed by forming the needle-like portion 23 having a blade by squeezing the tip of the pipe 22 into two steps, or a plurality of steps or a curved shape as shown in the drawing. Then, when cutting the thin film 14 protruding from the pellicle frame 13, the cutting jig 21 is lowered by a certain amount to pierce the thin film 14 with the blade 23 as shown in FIG.
Cutting is performed by moving it toward the front at a constant speed along the edge of, but at this time, it is on the same level as the upper surface of the pellicle frame and is cut by the blade 23 from the discharge port 24 located on the front side of the blade tip. The coating liquid 16 is discharged to the cutting position immediately before the cutting.

The cutting jig 31 shown in FIGS. 7 and 8, the front end of the pipe 32 obtained by a needle 33, when cutting the film 14 which protrude from the edges of the pellicle frame 13, FIG. 8
As shown in FIG.
The thin film 14 is pierced into the thin film 14 and is horizontally moved along the edge of the frame 13 at a constant speed to perform cutting. At this time, the four front, rear, left and right discharge ports 34 at the same level as the upper end surface of the pellicle frame respectively The coating liquid 16 is designed to be discharged in a fixed amount.

[0017] While being gripped by the hand of even robot Izure cutting jig to above to cut the film, since the pellicle frame being generally rectangular shape, a cutting tool shown in FIGS. 5 and 6, When the cutting edge reaches the corner of the pellicle frame, the cutting jig must be turned by 90 ° to change its direction, and therefore a robot using such a cutting jig needs a mechanism for turning the robot hand. On the other hand, Fig. 7
Further, as shown in FIG. 8 , the cutting jig in which the cutting edge has a needle-like shape and the discharge ports 34 are formed at four positions in the front, rear, left, and right does not need to change its direction with respect to the corners of the pellicle frame. It is possible to use a robot that does not require a mechanism for turning the hand, has a simple structure, and is easy to control.

[0018]

EXAMPLES Example 1 FIG. 3 and FIG. 4 in a clean room under a dust-free environment.
As shown in FIG. 3, after the cellulose thin film 14 taken on the temporary frame 15 is adhered to the aluminum pellicle frame 13, the portion protruding from the edge of the pellicle frame 13 is cut by the cutting blade 11 with metal attached to the cutting blade 11 or The pipe 12 made of resin was cut while discharging the coating liquid.

Here, a design knife (trade name) manufactured by Olfa Co. is used as a cutting blade, and a fluorine-containing resin (trade name "CYTOP") manufactured by Asahi Glass Co., Ltd. is used as a coating liquid.
4.0 g of fluorocarbon-based organic solvent (trade name "CT-Solv.13C" manufactured by Asahi Glass Co., Ltd.) is added to 46.0 g of 23 g.
A saturated solution obtained by immersing at 5 ° C. for 5 hours was used. The content of the resin in this case was about 8 wt%. Then, after attaching the former cutting blade to the hand of the Cartesian coordinate system robot having a tip rotation mechanism, it is moved at a speed of 6 mm / sec along the edge of the pellicle frame in the direction of the arrow in FIG. 4 to precede the cutting by the blade. The amount of coating liquid discharged from the discharge port 24 of the pipe 12 is 4
When released while releasing at 0 μl / min and cutting while applying the cutting spot, the cutting can be performed smoothly without any problem, and coating at the frame edge is possible within 1 mm of both the coating width of the coating liquid and the dripping of the outer surface of the pellicle frame. It was The above cutting operation was repeated three times, and the amount of dust generated around the cut portion was measured with a particle counter during thin film cutting. The results are shown in Table 1.

Comparative Example 1 The cutting was carried out under the same conditions as in Example 1 except that the coating liquid was discharged following the cutting by the cutting blade, and the cut end face immediately after cutting was coated with the coating liquid. Similar to No. 1, it was performed satisfactorily. During the thin film cutting, the amount of dust around the cut portion was measured in the same manner as in Example 1. The results are shown in Table 1 below.

[0021]

[Table 1] As shown in Table 1, in Example 1 in which the coating liquid was applied to the cut surface, the amount of dust generated was drastically reduced as compared with Comparative Example 1 in which the cut surface was cut, and generation of large foreign matter of 1 μm or more was completely absent.

Example 2 In Example 1, the cutting speed by the cutting blade was 10 mm / se.
Even if c was used, the thin film could be cut satisfactorily. Even if a 3% resin solution was used as the coating liquid, good cutting could still be achieved, but the coating width of the coating liquid and the sagging of the outer surface of the pellicle frame were 1 mm, which enabled coating at the frame edge.

Comparative Example 2 Using a cutting jig 21 shown in FIGS. 5 and 6 consisting of a pipe having an inner diameter of 0.7 mm, and using a 3% resin solution as a coating liquid, the cutting speed was 2 mm / sec, 6 mm / sec, 10 mm / se
When cutting was performed in place of c, the thin film could be cut at a cutting speed of 2 mm / sec, but could not be cut at a cutting speed of 6 mm / sec or more. The above results are shown in Table 2 below.

[0024]

[Table 2] As shown in Table 2, it is preferable to use a cutting jig having a blade for cutting the thin film. In the cutting jig having a blade, a saturated resin solution is used as a coating liquid, and the cutting can be performed even if the cutting speed is increased. It was possible.

[0025]

According to the cutting method of the first aspect, since the thin film is cut by the physical cutting means, it is possible to cut a thin film of any film material, and the film dissolution time is not required as compared with the cutting by the organic solvent. Therefore, the film cutting speed can be increased, and since the cut portion is coated with the coating liquid prior to the cutting, dust generation from the cut end face can be suppressed and the cutting speed can be increased.

According to the cutting method of the second aspect, the resin is fused to the thin film so that the coating is surely performed. As in the cutting method of the third aspect, a saturated solution of the resin is used as the coating liquid. With this, the thin film is not cut by the solvent, the cut end surface is reliably covered with the resin, and the finish is clean and dust can be prevented. Claim 4
When the resin used is the same as or similar to the film material as in the cutting method described above, the resin is more surely fused into the thin film to enable the coating. According to the cutting method and the cutting jig described in claims 5 and 8, even if the coating liquid is a saturated resin solution, it is possible to cut at a high cutting speed.

According to the cutting jig of the sixth aspect, it is not necessary to separately provide a device for moving the cutting jig and a device for moving the applicator. When the applicator is in the shape of a pipe as in the cutting jig described in claim 7, the structure is simple and not bulky, and the applicator can be easily attached to or incorporated in the cutting jig.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a state when a thin film taken on a temporary frame is stretched on a pellicle frame and then cut.

FIG. 2 is an enlarged sectional view of a main part of a conventional example.

FIG. 3 is a sectional view showing a cutting method according to the present invention.

FIG. 4 is an enlarged side view of the same.

FIG. 5 is a perspective view of a cutting jig.

6 is an enlarged sectional view of an essential part showing a state at the time of cutting using the cutting jig shown in FIG.

FIG. 7 is a perspective view of still another example of the cutting jig.

FIG. 8 is a view showing a state at the time of cutting using the cutting jig shown in FIG .
FIG.

[Explanation of symbols] 1, 13, ... Pellicle frame 2, 15 ... Temporary frame 3, 14 ... Thin film 5 ... Jig 11 ... Cutting blade 12 ... Pipe 12a ... 16 ... Coating liquid 21 ... Cutting jig 22, 32 ... Pipe 23 ... Needle-like parts 24, 34 ... 33 ... Needle

Front page continued (72) Inventor Hiroaki Nakagawa 6-1-2, Waki, Waki-cho, Kuga-gun, Yamaguchi Mitsui Chemicals, Inc. (56) Reference JP-A-8-292553 (JP, A) JP-A-8 -95234 (JP, A) JP-A-2-145292 (JP, A) JP-A-7-281421 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03F 1/14 H01L 21/027

Claims (9)

(57) [Claims] 1. A method of cutting a thin film in which a thin film protruding from an edge outside the frame is cut by a physical cutting means after a thin film is adhered to one end face of a pellicle frame, and the thin film is cut by the physical cutting means. A method for cutting a thin film in a method for manufacturing a mask protection device, characterized in that a coating liquid is discharged to a cutting position from an applicator attached to or built in a physical cutting means to apply the coating liquid. 2. The method of cutting a thin film in the method of manufacturing a mask protection device according to claim 1, wherein a solution in which a resin is dissolved in an organic solvent is used as the coating liquid. 3. A method of cutting a thin film in a method of manufacturing a mask protection device according to claim 1, wherein a saturated solution in which a resin is saturated and dissolved in an organic solvent is used as the coating liquid. 4. The method of cutting a thin film in a method of manufacturing a mask protection device according to claim 2, wherein the resin is the same as or similar to the material of the thin film. 5. The method of cutting a thin film in a method of manufacturing a mask protection device according to claim 1, wherein the physical cutting means is a blade. 6. A cutting jig used as a physical means in the cutting method according to claim 1, wherein a coating liquid applicator is additionally provided or incorporated. 7. The cutting jig according to claim 6, wherein the applicator has a pipe shape. 8. The cutting jig according to claim 7, which is formed in a pipe-shaped applicator. 9. The cutting jig according to claim 6, wherein the cutting jig is a blade.