JP2006113328A - Large-size pellicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a large-size pellicle capable of uniformly attaching a frame to a mask over the whole periphery by specifying conditions of a mask pressure-sensitive adhesive material using a hot-melt material with respect to the pellicle having an area of ≥1,000 m<SP>2</SP>. <P>SOLUTION: A typical constitution of the large-size pellicle is as follow: The mask pressure-sensitive adhesive material for attaching the frame to the mask is a hot-melt material having pressure-sensitive adhesive property even at the normal temperature and has such a shape as to satisfy the relation; c0≥c≥c0×0.5 or 2≤c/b≤10, wherein (c) is the maximum width of respective cross-sections of hot-melt applied on the bottom surface of the frame, c0 is the width of the bottom surface of the frame and (b) is the height of the hot-melt. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a large pellicle, and more particularly, when a thin film transistor (TFT) or a color filter (CF) constituting a liquid crystal display (LCD) is manufactured, foreign matter adheres to a photomask used in a lithographic process. It relates to a pellicle for prevention.

  2. Description of the Related Art Conventionally, in a lithographic process when manufacturing a TFT constituting an LCD, dust prevention means called a pellicle is placed on a photomask to prevent foreign matter from adhering to the photomask. When foreign matter adheres to the surface of the photomask, the foreign matter forms an image on the photoresist formed on the liquid crystal panel and causes a circuit pattern defect. However, when the pellicle is placed on the photomask, The foreign matter adhering to the surface does not form an image on the photoresist formed on the liquid crystal panel due to the shift of the focus position, and does not cause a defect in the circuit pattern.

  As shown in FIG. 3, the pellicle 10 has a pellicle film 12 made of a polymer film stretched and bonded to one edge surface of a frame 11 having a shape matching the shape of the photomask 1 and having a thickness of several millimeters. ing. Then, as shown in FIG. 4, a mask adhesive material 13 is provided on the other edge surface of the frame 11 and is adhered to the surface of the photomask 1. As a material for the polymer film constituting the pellicle film for TFT mask, a material taking into consideration the transparency of exposure light, such as a cellulose derivative such as nitrocellulose or an amorphous fluoropolymer, is used.

  Regarding the large pellicle as in the present invention, the applicant of the present patent application is also disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-109135 (Patent Document 1), Japanese Patent Application Laid-Open No. 2001-201845 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2002-296863. (Patent Document 3) and other inventions have been developed and patent applications have been filed.

  In the invention of the above-mentioned Patent Document 1, the width of the long side of the large pellicle frame for expanding and supporting the large pellicle film is made larger than the width of the short side to ensure the strength of the long side, and the long side frame It is the invention which was made to suppress the bending which goes inside.

  Further, the invention of Patent Document 2 prevents a pressure difference between the inside and outside of the large pellicle from occurring when the large pellicle film is stretched on the large pellicle frame, thereby causing the large pellicle film to swell or dent in the vertical direction. Therefore, the present invention is such that a large pellicle frame is provided with a vent hole so that the inside and outside of the frame have the same atmospheric pressure.

  Further, the invention of Patent Document 3 is formed such that at least a pair of sides of a large pellicle frame for extending a large pellicle membrane protrude toward the outside of the frame, thereby bending toward the inside of the long side frame. This is an invention in which the effective exposure area of the photomask is ensured by suppressing.

JP 2001-109135 A JP 2001-201845 A JP 2002-296863 A

The above-mentioned large-sized pellicle for liquid crystal has an area of 1000 cm ² or more, and its frame has a larger flatness (waviness is larger) than a frame of a semiconductor pellicle generally having an area of about 238 cm ² . For this reason, in order to evenly attach the pellicle frame to the mask, it is necessary to use a large-sized pellicle mask adhesive material 13 (see FIG. 4) having a large amount of elastic deformation. Is used.

  However, since the foam has countless cells open in the cross section, foreign substances such as dust may enter the cells and come out after being attached to the mask to contaminate them. In order to prevent such a situation, conventionally, an adhesive material is applied to the side surface of the foam to cover the side surface.

  By the way, since the frame for large pellicles has a high degree of flatness, there are places where the mask adhesive material is partially stretched when a load is applied to affix the pellicle to the mask and the load is released. The adhesive material may be torn. This tendency becomes more prominent as the frame area for the large pellicle increases.

Therefore in a particularly area 1000 cm ² or more for large pellicles, by using a cell-free hot-melt material as the foam as a mask pressure-sensitive material, it is not necessary to apply an adhesive material on the side surfaces, the prevention of occurrence of foreign matters The reliability of will increase. However, the large pellicle frame has a large flatness and a large frame width. Depending on the type, the long side width and the short side width may be different. It is difficult to form a hot melt that sticks to the mask uniformly over the entire circumference of such a frame.

Therefore, the present invention provides a large pellicle capable of uniformly attaching a frame to the mask over the entire circumference by specifying the cross-sectional shape of a mask adhesive material using a hot melt material in a pellicle having an area of 1000 cm ² or more. The purpose is that.

In order to solve the above problems, a typical configuration of a large pellicle according to the present invention is provided over a pellicle film having an area of 1000 cm ² or more, a frame on which the pellicle film is stretched, and the entire circumference of the frame. In a pellicle comprising a mask adhesive material for attaching a frame to a mask, the mask adhesive material is a hot melt material having adhesiveness at room temperature, and has a maximum width of each cross section of hot melt applied to the bottom surface of the frame. c, where the width of the bottom of the frame is c0, it is provided with a shape satisfying c0 ≧ c ≧ c0 × 0.5.

Another typical configuration of the large pellicle according to the present invention includes a pellicle film having an area of 1000 cm ² or more, a frame on which the pellicle film is stretched, and an entire periphery of the frame, and the frame is attached to a mask. In the pellicle comprising a mask adhesive material for attaching, the mask adhesive material is a hot-melt material having adhesiveness at room temperature, and the maximum width of each cross section of the hot melt applied to the bottom of the frame is c, When the height is b, it is provided in a shape satisfying 2 ≦ c / b ≦ 10.

Moreover, the structure which combined the said structure is also possible. That is, in a pellicle comprising a pellicle film having an area of 1000 cm ² or more, a frame on which the pellicle film is stretched, and a mask adhesive material that is provided over the entire periphery of the frame and is attached to the mask. The pressure-sensitive adhesive material is a hot-melt material having adhesiveness at room temperature, and c0 ≧ c ≧ c0 × 0.5 where c is the maximum width of each cross section of the hotmelt applied to the frame bottom surface and c0 is the frame bottom width. And the height of the hot melt is b, it is provided in a shape satisfying 2 ≦ c / b ≦ 10.

According to the present invention, in a pellicle having an area of 1000 cm ² or more, a hot melt material can be used as a mask adhesive material, and the frame can be uniformly attached to the mask over the entire circumference. A large pellicle that does not generate dust can be provided.

  An embodiment of a large pellicle according to the present invention will be described. The description is applied to the basic configuration of the pellicle described with reference to FIG. 4, and the same members are denoted by the same reference numerals and the description thereof is omitted.

  In the pellicle 10 according to the present embodiment, the mask adhesive material 14 is a hot-melt material having elasticity and adhesiveness at room temperature. The mask adhesive material 14 is melted by heat and applied to the bottom surface of the frame 11 (the surface opposite to the surface on which the pellicle film 12 is stuck), and is cooled and fixed. Until the pellicle 10 is affixed to the photomask 1, a protective film is affixed to the adhesive surface of the mask adhesive material 14 to prevent inadvertent adhesion. In use, the protective film is peeled off, and the entire frame 11 is bonded to the photomask 1 by pressurizing the frame 11 together.

  As shown in FIG. 1, the height of the frame 11 of the pellicle 10 is a, the height of the mask adhesive 14 is b, the width of the frame 11 is c0, and the maximum width of each cross section of the mask adhesive 14 is c.

About the width | variety of the mask adhesive material 14, it has provided in the shape which satisfy | fills c0> = c> = c0 * 0.5. That is, the width of the mask adhesive material 14 does not exceed the width of the frame 11 and is at least half the width of the frame 11. The reason why c0 ≧ c is that if the mask adhesive material 14 protrudes beyond the frame 11, the hot melt that protrudes in the photolithography process may block exposure light. The reason why c ≧ c0 × 0.5 is set is that, since the area is 1000 cm ² or more, a large pellicle having a large flatness can obtain a sufficient affixing area and stably affix to the mask. This is because it becomes possible.

  Even if the width of the short side and the long side of the frame 11 are different, by defining the width of the mask adhesive material 14 by the above range, a sufficient bonding area and bonding strength can be obtained.

  About the height of the mask adhesive material 14, it has provided in the shape which satisfy | fills 2 <= c / b <= 10. That is, the height of the mask adhesive material 14 is in the range of half to 1/10 of the width of the mask adhesive material 14.

  When c / b> 10, the height of the adhesive material becomes low (thin) and the following problems occur. First, since the amount of elastic deformation is small, it becomes difficult to absorb the distortion of the frame 11. On the other hand, the flatness of the frame 11 is large in the large pellicle. For this reason, after adhering to the photomask 1, the mask adhesive material 14 may be peeled off from the frame 11 and the photomask 1 over time, and a gap may be partially generated. Further, since the mask adhesive material 14 is thin, when the frame 11 is pressed against the photomask 1, the exposed portion of the frame 11 (the portion where the mask adhesive material 14 is not applied) contacts the photomask 1 and is damaged. There is a risk that.

  If 1> c / b, the height of the mask adhesive material 14 becomes too high with respect to the width of the frame 11. For this reason, when the frame 11 is pressed against the photomask 1, the mask adhesive material 14 may be deformed and protrude from the frame 11 in the width direction. This is not preferable because it reduces the effective area of the pellicle.

  FIG. 2 shows specific numerical examples. However, the following specific examples are merely examples for facilitating understanding of the invention, and do not limit the present invention.

  As shown in FIG. 2A, the frame 11 of the pellicle 10 has a long side and a short side having different widths, the long side having a width of 8 mm and the short side having a width of 7 mm.

  As shown in FIG. 2B, on the short side, the height b of the mask adhesive material 14 is 1.6 mm and the width c is 5 mm with respect to the width of the frame 11. At this time, c / b = 3.13, which satisfies the above conditions. As shown in FIG. 2C, on the long side, the height b of the mask adhesive material 14 is 1.6 mm and the width c is 6 mm with respect to the width 8 mm of the frame 11. At this time, c / b = 3.75, which satisfies the above conditions.

  When the height of the mask adhesive 14 is fixed at 1.6 mm, in order to satisfy the above condition, the length is 3.5 to 7 mm on the short side and 4 to 8 mm on the long side. Therefore, the width of the mask adhesive material 14 may be set in the common range of 4 to 7 mm without changing the width of the mask adhesive material 14 on the short side and the long side, and the same width may be applied over the entire circumference. .

The present invention can be used as a large pellicle having an area of 1000 cm ² or more.

It is a figure explaining the structure of the pellicle which concerns on the Example of this invention. It is a figure explaining the specific example of the pellicle which concerns on the Example of this invention. It is a figure explaining the outline of a pellicle. It is a figure explaining the structure of the conventional pellicle.

Explanation of symbols

1 ... Photomask
10… Pellicle
11 ... Frame
12… Pellicle membrane
13… Mask adhesive
14 Mask adhesive

Claims (3)

A pellicle film having an area of 1000 cm ² or more;
A frame on which the pellicle film is stretched;
In a pellicle that is provided over the entire circumference of the frame and includes a mask adhesive for attaching the frame to a mask,
The mask adhesive material is a hot melt material having adhesiveness at room temperature,
A large pellicle having a shape satisfying c0 ≧ c ≧ c0 × 0.5, where c is the maximum width of each cross section of hot melt applied to the frame bottom and c0 is the frame bottom width. A pellicle film having an area of 1000 cm ² or more;
A frame on which the pellicle film is stretched;
In a pellicle that is provided over the entire circumference of the frame and includes a mask adhesive for attaching the frame to a mask,
The mask adhesive material is a hot melt material having adhesiveness at room temperature,
A large pellicle having a shape satisfying 2 ≦ c / b ≦ 10, where c is the maximum width of each cross section of the hot melt applied to the bottom of the frame and b is the height of the hot melt. A pellicle film having an area of 1000 cm ² or more;
A frame on which the pellicle film is stretched;
In a pellicle that is provided over the entire circumference of the frame and includes a mask adhesive for attaching the frame to a mask,
The mask adhesive material is a hot melt material having adhesiveness at room temperature,
When the maximum width of each cross section of the hot melt applied to the frame bottom is c and the frame bottom width is c0, c0 ≧ c ≧ c0 × 0.5 is satisfied,
A large pellicle having a shape satisfying 2 ≦ c / b ≦ 10, where b is the height of the hot melt.

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