KR20080068528A - Method of coating film adhesive on the pericle frame - Google Patents

Abstract

A method for coating a film adhesive on a pellicle frame is provided to regularly coat a proper amount of adhesive on the pellicle frames which have different widths. A method for coating a film adhesive at an end of a pellicle frame(14) comprises the steps: continuously supplying the film adhesive from a discharge port(12); and moving the discharge port for coating. The outer diameter of a coating head(11) is 60~120% of the width of the pellicle frame.

Description

Application method of film adhesive to pericle frame {METHOD OF COATING FILM ADHESIVE ON THE PERICLE FRAME}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a method for producing a lithographic ferrule for use as a dust cover in manufacturing a semiconductor device, a printed board or a liquid crystal display, and more particularly, to a method for applying and forming a pellicle film adhesive layer on a pellicle frame. will be.

In the manufacture of semiconductors such as LSI and ultra-LSI, or in the manufacture of liquid crystal displays, a pattern is produced by irradiating light onto a semiconductor wafer or a liquid crystal display plate, but a photomask or a reticle to be used at this time (hereinafter, simply referred to as a photomask) If dust adheres to the dust, the dust absorbs light or refracts the light. Therefore, the transferred pattern may be deformed, the edges may be uneven, and the base may be dirty. There was a problem.

For this reason, these operations are usually performed in a clean room, but it is still difficult to always keep a photomask clean. Therefore, exposure is performed after a pellicle is adhered as a dust film on the surface of the photomask. In this case, the foreign matter is not directly attached to the surface of the photomask, but is attached on the ferric, so that when the lithography focuses on the pattern of the photomask, the foreign material on the ferric becomes irrelevant to the transfer.

In general, a pellicle adheres to or adheres to a top surface of a pellicle frame made of aluminum, stainless steel, polyethylene, or the like, which is a transparent pellicle film made of nitrocellulose, cellulose acetate, fluorine resin, or the like that transmits light well. In addition, an adhesive layer made of a polybutene resin, a polyvinyl acetate resin, an acrylic resin, or the like, and a release layer (separator) for protecting the adhesive layer are formed at the lower end of the ferric frame.

In the case of a small pellicle used for semiconductor applications, the film adhesive surface width of the pellicle frame is as small as 1.5 to 2 mm, and application of the film adhesive is not so difficult. However, in the case of large sized pellicles used for liquid crystal applications, the width of the pellicle frame (film adhesive surface width) may be 10 mm or more, and it is very difficult to apply the film adhesive without applying it. In addition, in the case of a liquid crystal used in liquid crystal applications, the length of the pericle frame (membrane bonding surface width) is often different between the long side and the short side, and in this case, it is more difficult, thereby forming chamfers having different sizes in the frame. It is also proposed to make the film adhesion surface width the same (refer patent document 1). However, large chamfering on the ferrule frame is not desirable because it leads to a decrease in rigidity.

The simplest way to apply the entire width of the perimeter frame adhesive surface without coating is to increase the amount of liquid to be applied.However, the membrane adhesive layer becomes thicker than necessary to damage the appearance near the adhesive surface. It is necessary to reduce the height of the, resulting in a decrease in the frame rigidity. In particular, in the case of bonding the pellicle film in a soft state such as a UV-curable adhesive, there is a concern that the pellicle frame may be pushed out or spilled. In addition, the viscosity of the membrane adhesive solution may be increased to increase the viscosity and the amount of the liquid, but the amount of the solvent evaporated after application increases, causing the membrane adhesive to agglomerate during drying, or to be inclined by flow due to the bending of the frame. Because of this, there is a limitation as a condition, and this cannot eliminate unapplied only.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2001-109135

In general, a dispenser is used to apply the film adhesive. The schematic diagram which apply | coats a pellicle membrane adhesive agent to a pellicle frame membrane adhesion surface by the air pressurized dispenser is shown in FIG. As the liquid feeding means, a syringe pump, a plunger pump, a tube pump and the like may be used in addition to air pressurization, but parts other than the liquid feeding and liquid volume control methods are basically the same.

The syringe 53 is filled with a membrane adhesive solution, and is pushed out of the discharge port 52 at the tip of the needle 51 attached to the syringe 53 by a pressurized source such as air connected to the syringe 53. . Then, the film adhesive solution is moved dropwise from the discharge port 52 at the tip of the needle, and the coating is applied over the entire circumference of the end face of the ferrule frame 54.

This method is generally used because there is an advantage that the discharge amount is easy to control despite the fact that the structure of the device is simple and the maintenance and repair is easy.

Needle 51 is usually used in the form of a needle having a through-hole in the center alone, the film adhesive solution 55 continuously dropped from the tip of the needle 51 forms the appropriate spreading based on the viscosity, The application proceeds while the width is expanded to the shape spreading toward the end rearward in the direction of travel of 51.

When the spread of the membrane adhesive is insufficient for the width of the membrane adhesive surface, it is conceivable to provide a plurality of needles 61 in the transverse direction with respect to the advancing direction of the needle (Fig. 6 (a)). However, in this case, when the application | coating side is moved and the advancing direction of the needle 61 changes 90 degrees, the needle 61 will be arranged in plurality in the advancing direction, and it is meaningless.

As a countermeasure against this, it is considered to provide a plurality of needles 61 obliquely in the advancing direction of the needles 61 (Fig. 6 (b)). In this case, the needle 61 can be arrange | positioned also in the width direction also in two orthogonal sides. However, as is clearly shown in Fig. 6 (b), in the case of a general quadrilateral pericle, two corner portions A and C can be appropriately applied, but two corner portions adjacent to them are applied. In (B, D), the large uncoated portion 64 is generated. Reference numeral 63 denotes a ferry frame.

In order to prevent this, a mechanism for rotating the needle portion is usually added to an application device composed of XY biaxial or XYZ triaxial robots. However, the cost increases mechanically, and it is considerably complicated for control including liquid supply. It is very difficult in reality. In the part reaching the corner part, it is necessary to finish the needle rotation at a moment while changing the direction of the straight line application by 90 °, but it is very difficult to control the discharge amount of the coating liquid so that the unapplied or pushed out does not occur even if the needle rotates rapidly. Because.

In addition, the adhesive discharged from these plurality of needles is agglomerated inside each needle by the surface tension of the liquid, and cannot actually spread to the outside of the frame width as expected.

If the width of the membrane adhesive side of the pellicle frame is different, the gap of these needles will flow down unless it is set to the narrow side, but for this reason, the membrane adhesive is applied to both narrow and wide sides without coating. Is very difficult.

Incidentally, as shown in Fig. 6 (c), when four needles 61 are arranged so as to correspond to the corner portion and the two sides that are orthogonal so that the rotation mechanism is not necessary, the passing position of the needles overlaps a plurality, so that the coating liquid 62 In addition to the significant inclination in the distribution of), problems such as uncoated or pushed out are also likely to occur at the corners.

In view of the above, a method of stably applying an appropriate amount of an adhesive without unapplied or pushed out to a pellicle frame, particularly a wide pellicle frame used for liquid crystal applications, has not been obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for forming an adhesive layer having an excellent appearance by applying an appropriate amount of adhesive to a wider pellicle frame without being uniformly uncoated or pushed out. .

In the method of applying the film adhesive to the ferric frame according to the present invention, the film is applied by moving the discharge port while continuously dropping the film adhesive from the discharge port. Characterized in that the range of 60 to 120% of the cotton width (claim 1).

In addition, in the case where the width of the film adhesive surface of the ferrule frame is different from the long side to the short side, the width in one direction of the coating head is in the range of 60 to 120% of the long side, and the width in the direction orthogonal to that is 60 to the short side. It is preferable to move the coating head so that it is formed in the range of 120% and the outer diameter corresponding to the long side width when applying the long side and the outer diameter corresponding to the short side width when applying the long side are in a direction orthogonal to the moving direction of the coating head. 2).

The application head is preferably a convex shape in which a discharge port is formed at the center of the tip and has a center at the top (claim 3).

At this time, it is particularly preferable that the convex shape is formed by one or a plurality of curved surfaces (claim 4).

The gap between the top part of the application head and the surface of the pericle frame during application is preferably 1.5 mm or less, and the capillary phenomenon is controlled so that 80% or more of the area of the application head surface is kept in contact with the pressure-sensitive adhesive solution. Good (claim 5). By maintaining and applying this state, the film adhesive can be applied without stably causing uncoating.

Effect of the Invention

According to the present invention, an appropriate amount of adhesive is uniformly and unapplied also to a pellicle frame having a wide membrane bonding surface, a pellicle frame having a different width between the long side and the short side, and a pellicle frame other than a quadrangular shape. It can be applied stably without being pushed out, and as a result, a film adhesive layer excellent in appearance can be formed.

EMBODIMENT OF THE INVENTION Hereinafter, although this invention is demonstrated in detail by drawing, this invention is not limited to this.

BRIEF DESCRIPTION OF THE DRAWINGS It is a top view and sectional schematic drawing which shows one Embodiment of the front-end | tip structure of the coating head in which the discharge port by this invention is formed. 2 is a plan view and a cross-sectional schematic view showing an embodiment of the present invention with respect to a pellicle frame having different membrane bonding surface widths at long and short sides.

The application head 11 is attached to the tip of the syringe 16 filled with the membrane adhesive solution so that there is no leakage of liquid, and the robot can move freely in the horizontal plane and in the perpendicular orthogonal triaxial directions by a moving means (not shown) by a robot. It is supposed to be. The film adhesive solution 15 is moved from the discharge port 12 formed in the application head 11 while the membrane adhesive solution 15 is dropped, and the film adhesive surface of the ferrule frame 14 is rounded to form a membrane adhesive. Application is carried out.

Here, the conveyance means (not shown) of the membrane adhesive can use various conveyance means which can control supply amount and discharge / stop, such as a syringe pump, a plunger pump, a tube pump, in addition to gas pressurization, such as air pressurization and nitrogen pressurization.

At this time, the outer diameter width a of the application head 11 is preferably in the range of 60 to 120% of the width of the film adhesive surface b of the ferrule frame 14. When the film adhesion surface width is different from the long side to the short side, as shown in the plan view of FIG. 2, the width e in one direction of the coating head is in the range of 60 to 120% of the long side width and in the direction orthogonal to it. f) is formed in the range of 60 to 120% of the short side width, and when the long side is applied, the outer diameter (e) corresponding to the long side width, and when the short side is applied, the outer diameter (f) corresponds to the moving direction of the application head. What is necessary is just to install and move a coating head so that it may become orthogonal.

In FIG. 1, the gap | interval of the front end 13 of the coating head 11, and the pericle frame 14 is filled with the membrane adhesive solution discharged from the discharge port 12 invading by capillary phenomenon. As a result, even if it is a wide pericle frame, a film adhesive is continuously supplied to the outer side and can apply | coat without generating uncoated.

At this time, since the film adhesive solution on the lower surface of the application head 11 is always trying to agglomerate by surface tension, the width a of the application head 11 is wider than the membrane adhesion surface width b, or Even if the outer diameter part is pushed outward and moved, if the amount does not exceed the limit, the membrane adhesive does not drop outward. On the contrary, even if the outer diameter width a of the application | coating head 11 is smaller than the membrane adhesion surface width b, application | coating may be possible without uncoating depending on the viscosity of the membrane adhesive agent to be used.

Therefore, it is preferable to determine the viscosity (concentration) of the film adhesive and the specification of the application head 11 appropriately in consideration of the width of the pericle frame film adhesion surface, the film thickness after drying, the appearance, and the like.

Similarly, the outer diameter width of the coating head 11 is also in the range of 60 to 120% of the film bonding surface width, particularly preferably 80 to 100% in consideration of the film bonding surface width, the film adhesive viscosity, and the distance between the coating head and the film bonding surface. It is good to determine suitably in the range of. In addition, the coating heads 21 having different longitudinal and horizontal outer diameters as shown in Fig. 2 are manufactured in a circular shape in accordance with the large diameter side, and the plane is cut in one direction to obtain a desired shape. However, the production is the simplest and practically without any problem. .

The application head 11 is preferably formed in a convex shape in which a discharge port 12 is formed at the center of the tip, and the center is the top. Moreover, it is especially preferable that this convex shape is formed by one or more curved surfaces.

The presence of the discharge port in the center portion not only makes the coating stable at either of the two orthogonal sides, but also has the advantage that the droplet at the tip just before application is stable, and the discharge port becomes difficult to dry.

In addition, although the shape of the front-end | tip 13 of the application | coating head 11 can be apply | coated even if it is substantially flat, in order not to make the seam of the start / end point of application | coating outstanding, and to stabilize application | coating at a corner part, It is better to make it slightly convex.

The convex shape is most preferably a curved surface, particularly a curved surface of a rotating body, in which the film adhesive between the application head and the film adhesive surface is stable during the application of the film adhesive. Although the curvature of a curved surface is easy to produce uniformly, a combination of several kinds of curved surfaces may be used if necessary.

In addition, the difference c between the height of the top point and the outermost end of the width direction is appropriately considered in consideration of the relationship between the viscosity of the film adhesive, the outer diameter width a of the coating head 11, and the film adhesion surface width b. Although it is good to determine, it is good to set it as the range of 0.3-1 mm normally. Moreover, in order to adjust the wettability (contact angle) with a film adhesive, the front end 13 of the application head 11 may be surface-treated and processed.

As for the clearance gap d between the front-end | tip (normal part) 13 of the application | coating head 11 and the surface of the pericle frame 14 during application | coating, 1.5 mm or less is good, and as mentioned above, the application | coating head surface ( It is preferable to apply so that 80% or more of the area 13) is kept in contact with the film adhesive solution 15. Therefore, since the center part of a periphery is normally lined down by self weight normally, it is necessary to support from a downward direction so that this may be horizontal. This also has a secondary effect of preventing the film adhesive from flowing and biasing after application, and drying the film adhesive in a flat and excellent appearance.

In addition, it is needless to say that it is important to stably maintain the discharge amount of the film adhesive during the application and the moving speed of the application head. Maintaining this state at all times during application is an important point for performing good application.

In addition, the coating head may be integrally produced as shown by reference numeral 31 in FIG. 3A, and the bolt 35 or the like may be formed at the tip of the normal needle 34 as shown by reference numeral 33 in FIG. 3B. You may attach it. Reference numeral 32 denotes a syringe.

Although the material of the coating head should be resistant to solvents such as carbon steel, stainless steel, brass and other metals, and adhesives such as PTFE, it is quite laborious to process fine diameter holes in these materials with high precision and smoothness. . Therefore, as shown in Fig. 3 (a), it is more industrial to produce the discharge port portion separately using a commercially available needle as shown in Fig. 3 (b), and to assemble and use the needle. Is preferred.

<Example>

Hereinafter, although the Example of this invention is described, this invention is not limited to this.

Example 1

Initially, a rectangular aluminum alloy pellicle frame with an outer dimension of 1146 × 1366 mm, an inner dimension of 1122 × 1342 mm, a height of 6 mm, an inner dimension of a corner portion R 2, an outer dimension of R 6 mm, and a width of 12 mm on the membrane bonding surface was machined. It produced by the process, and after blasting by SUS bead about Ra 0.8-0.9, black anodized process was performed to the surface. This pericle frame was carried in a clean room of Class 1, washed and dried well with a neutral detergent and pure water, and then tested by applying a film adhesive to the end surface.

The schematic diagram of the film adhesive application apparatus used by this invention is shown in FIG. The door-shaped XYZ orthogonal triaxial robot 42 is attached to the mount 41, and the PP 43 syringe is attached to the Z-axis front-end | tip.

The PP syringe 43 is connected to an air pressurized dispenser (manufactured by Iwashita Engineering, not shown), and both the robot operation and the coating liquid discharge are controlled by the control unit of the three-axis robot 42. And on this apparatus, the pellicle frame 44 of the specification mentioned above was fixed so that an adhesive application end surface might be horizontally upward. Moreover, in order to prevent the curvature by the self-weight of the pellicle frame 44, and to keep a film adhesion surface horizontally, the support made of POM resin was provided under each circumference at about 200 mm intervals.

And the syringe 43 was filled with the silicone adhesive (Shin-Etsu Chemical Co., Ltd. make, brand name: X-40-3004A) diluted to 15% with toluene as a film adhesive solution.

The application head 11 of the shape shown in FIG. 1 is attached to the front-end | tip part of this syringe 43. As shown in FIG. The coating head 11 machined and produced brass, and the surface was nickel-plated for rust prevention. However, the part of the discharge port 12 was processed by press-fitting the pipe of SUS304 into the large diameter hole.

The outer diameter a of the application head 11 is set to 12 mm in the same manner as the adhesive surface width b of the ferrule frame 14, and the shape of the front end 13 is a spherical surface having a curvature R 30 and a diameter of the discharge port 12. Was 0.3 mm. In addition, the clearance gap between the front end 13 of the coating head 11 and the surface of the pericle frame 14 during application | coating was set to about 0.8 mm.

And the film adhesive application was performed by automatic operation, and it air-dried until the membrane adhesive did not flow. Subsequently, the fertilizer frame was further heated to 120 ° C by a high frequency induction heating apparatus (not shown), and the solvent was completely dried, and the adhesive was completely cured.

In this way, the test sample produced and tested was conveyed to the dark room, and the external appearance of the film adhesive coating surface was observed with the halogen lamp of 300,000 lux of light quantity. As a result, the film adhesive end surface was fully apply | coated with a film adhesive, and the uncoated part was not found also in a corner part. There was also no extrusion of the membrane adhesive into the inner, outer, and chamfered portions of the pericle frame. In addition, the surface had a glossy smooth surface and was excellent in appearance without any wave or blur.

Example 2

Initially, rectangular aluminum with an outer dimension of 436 × 745.5 mm, an inner dimension of 418 × 734.5 mm, a height of 6 mm, an inner dimension of the corner portion R 2 mm, an outer dimension of R 9 mm, a long side width of 9 mm and a short side width of 5.5 mm. An alloy pericle frame was produced by machining, and after blasting was performed with SUS beads at about Ra of 0.8 to 0.9, the surface was subjected to black anodized treatment. This pericle frame was carried in a clean room of Class 1, washed and dried well with a neutral detergent and pure water, and then tested to apply a film adhesive to the end surface.

Although the thing exactly the same as the said Example 1 was used as a coating device, only the coating head was taken as the shape shown in FIG.

The major axis outer diameter e of the application head 21 is 9 mm, the minor axis outer diameter f is 5.5 mm, the shape of the front end 23 is a spherical surface of curvature R 25 mm, and the diameter of the discharge port 22 is 0.3 mm. In addition, the clearance gap between the top point of the application | coating head 21 and the surface of the pericle frame 24 during application | coating was set to about 0.8 mm.

And the film adhesive application and evaluation were performed by the method similar to the said Example 1. As a result, the film adhesive end surface was fully apply | coated to the short side and the long side, and the uncoated part was not found even in a corner part. There was also no extrusion of the membrane adhesive into the inner, outer, and chamfered portions of the pericle frame. In addition, the surface had a glossy smooth surface and was excellent in appearance without any wave or blur.

[Comparative Example]

Using only the same ferrule frame and application device as in Example 1, only the discharge port portion of the lower part of the syringe has a shape in which two needles 61 are arranged as shown in Fig. 6 (b). Done.

Here, each needle was made of material SUS304, inner diameter 0.25 x outer diameter 0.46 mm, distance between needles 8 mm, and the shift angle with respect to the moving direction to 45 degrees.

And the film adhesive application and evaluation were performed by the method similar to the said Example 1,2. As a result, an uncoated portion extending linearly with a width of 0.5 to 1 mm at several inner edges of the long side and a crescent-type uncoated portion 64 having a maximum width of about 2 mm outside the corner portions B and D. Was found to be a coating quality that is difficult to say pass.

According to the application method of the film adhesive of the present invention, since it is possible to apply uniformly, homogeneously, and simply and reliably without leaving an adhesive on the adhesive surface of the pellicle frame of the pellicle frame, it is conducive to the industrial field using lithography technology. Big.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic diagram which shows one Embodiment of the front-end | tip structure of the coating head in which the discharge port by this invention is formed, (a) is a plan explanatory drawing, (b) is a cross-sectional explanatory drawing.

Fig. 2 is a schematic view showing one embodiment of the present invention with respect to a ferrule frame having a different film bonding surface width at the long side and the short side, and the A-A line and the B-B line cross-sectional explanatory drawing are attached.

3 is an explanatory view showing an embodiment of an attachment structure of an application head according to the present invention, (a) is a form in which a needle and an application head are integrated, and (b) another pair is used to bolt the application head to the tip of the needle. The attached form is shown.

4 is a schematic explanatory diagram of a film adhesive coating device used in the present invention.

It is explanatory drawing of the conventional method of apply | coating a film adhesive to a pericle frame by one needle.

Fig. 6 is an explanatory view of a conventional method for applying a film adhesive to a pellicle frame by a plurality of needles, (a) two needles in the horizontal direction, (b) two needles at an angle, and (c) a diamond shape. It is explanatory drawing which shows the example which used four needles, respectively.

<Description of the symbols for the main parts of the drawings>

11, 21: application head 12, 22, 52: discharge port

13: Front end (top) of the application head 14, 24, 44, 54, 63: Pericle frame

15 membrane adhesive solution 16, 32, 43, 53 syringe

a: coating head outer diameter width b: membrane bonding surface width

c: difference between the tip of the coating head and the height of the end of the outermost side in the width direction

d: distance between distal end of dispensing head and surface of pericle frame

Large arrow: Application direction 23: Application head tip

e: Coating head outer diameter width (long axis) f: Coating head outer diameter width (short axis)

31: Coating head (integral processing type) 33: Coating head (needle attachment type)

34, 51, 61: needle 35: attachment bolt

41: mount 42: XYZ orthogonal three-axis robot

55 membrane adhesive 62 membrane adhesive (coating liquid)

64: uncoated portion A, B, C, D: corner portion

Claims (5)

In the method of applying the film adhesive to the end face of the ferrule frame, application is carried out by moving the ejection opening while continuously dropping the film adhesive from the ejection opening, wherein the outer diameter width of the application head on which the ejection opening is formed is 60 times the width of the ferric frame. The coating method of the film adhesive characterized by the range of -120%. The width of one direction of the application head is in the range of 60 to 120% of the long side width, and the width in the direction orthogonal to it is short when the film adhesive surface width of the ferrule frame is different from the long side. It is formed in the range of 60 to 120% of the width, and the coating head is installed so that the outer diameter corresponding to the long side width when applying the long side and the outer diameter corresponding to the short side width when the short side is applied is the direction perpendicular to the moving direction of the coating head. A method of applying a membrane adhesive, characterized in that it moves. 3. The method of applying a film adhesive according to claim 1 or 2, wherein the coating head has a convex shape in which a discharge port is formed at the center of the tip, and the center is the top. 4. The method of applying a film adhesive according to claim 3, wherein the convex shape is formed by one or a plurality of curved surfaces. The gap between the top of the application head and the surface of the pericle frame during application is 1.5 mm or less, and 80% or more of the area of the application head surface is in contact with the pressure-sensitive adhesive solution by capillary phenomenon. A method of applying a membrane adhesive, characterized in that the state is controlled to be maintained.

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