JP2006267179A - Pellicle storage container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage container for a pellicle for photolithography, the container preventing deposition of foreign matters on a stored pellicle and contamination of a pellicle and keeping quality of the pellicle. <P>SOLUTION: The pellicle storage container comprises: a container body to place a pellicle and a cap body which covers a pellicle and is fitted and locked in the peripheral edge with the container body, wherein a pellicle is held by inserting a frame holding pin into a hole formed on an outer face of the pellicle frame. It is preferable that: the container body is made of a resin, and a metal component is joined to the container body; a positioning component to position the frame holding pin to hold a pellicle is mechanically linked with the metal component assembled in the container body; and an elastic material is laid at a contact portion of the frame holding pin holding the pellicle with the pellicle frame. More preferably, the container body and the cap body are made of a resin, each having antistatic performance of ≤1×10<SP>12</SP>Ω/unit square surface resistance. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pellicle storage container for storing, storing, and transporting a lithography pellicle used as a dust prevention when manufacturing a semiconductor device, a printed circuit board, a liquid crystal display, or the like.

  In the manufacture of semiconductor devices such as LSIs or liquid crystal displays, patterns are produced by irradiating a semiconductor wafer or liquid crystal glass original plate with light, but the photomask or reticle (hereinafter simply referred to as a photomask) used at this time has dust. If this is adhered, the dust blocks or bends the light, so that the transferred pattern is damaged.

For this reason, these operations are usually performed in a clean room, but it is still difficult to keep the photomask clean. Therefore, a method of sticking a pellicle as a dust guard on the photomask surface is taken.
In this case, the foreign matter does not adhere directly to the surface of the photomask but adheres to the pellicle. Therefore, if the focus is set on the pattern of the photomask during lithography, the foreign matter on the pellicle becomes irrelevant to the transfer.

  However, the pellicle has an effect of preventing foreign matter from entering the inside of the closed space formed by the pellicle after being attached to the mask. When it is inside the closed space, it is difficult to prevent foreign matter from adhering to the photomask surface. Therefore, not only is the pellicle itself required to have high cleanliness, but also the pellicle storage container used for storage and transportation is strongly required to have the ability to maintain the cleanliness.

As described above, the pellicle storage container is strongly required to have a performance capable of maintaining the cleanness of the pellicle during storage and transportation of the pellicle, and for that purpose, it is important to reduce the number of possible sources of dust generation as much as possible. It is.
Factors that can be a source of dust generation include the material, electrical characteristics, cleanliness, contact between the parts that make up the pellicle storage container, contact between the pellicle storage container and the pellicle, and contact with the pellicle storage container. For example, friction due to external force.
Therefore, it is necessary to consider various factors such as the material, strength, electrical characteristics, and method of fixing the pellicle that constitute the pellicle storage container.

A general pellicle storage container for a semiconductor is composed of a container body on which the pellicle is placed, and a lid body that holds the pellicle and is fitted and locked to the container body at the periphery thereof, and each material is a resin. And the lid has transparency.
Several methods have been proposed as a method for fixing a pellicle to a semiconductor pellicle storage container.
One of them is a method of pressing the upper end surface of the pellicle frame with the lid body wall (see Patent Document 1).

The method of pressing the upper end surface of the pellicle frame with the lid body wall as shown in Patent Document 1 has an advantage of securely holding the pellicle frame with a simple component structure. Because it is made of resin, it is weak to the force from the outside of the container, and when the entire pellicle storage container is twisted due to external force, a strong force is applied to the pellicle frame, and there is a high possibility of dust generation and deformation. Become.
This phenomenon becomes more prominent in a large liquid crystal pellicle whose side length exceeds 400 mm.

As another method, a method of increasing rigidity by incorporating a rib structure into the container body has been proposed (see Patent Document 2).
Although the method of increasing the rigidity by incorporating a rib structure into the container body as shown in Patent Document 2 has the advantage of reducing thermal deformation due to changes in the outside air temperature during transportation such as truck transportation and air transportation under hot weather. It is difficult to suppress the twist when the operator on the use side cantilever the edge of the container to a level that does not affect the pellicle.
As another fixing method, a method of indirectly fixing a pellicle frame by fixing a protective film that protects an adhesive material applied to the pellicle using a pressing body has been proposed (see Patent Document 3).

The method of fixing the pellicle frame indirectly by fixing a protective film for protecting the adhesive material applied to the pellicle using a pressing body, as shown in Patent Document 2, is included in the pellicle frame itself. Clamping the protective film without contacting it has the advantage that the force on the pellicle frame is less affected by the force from the outside of the pellicle container, but the protective film has a mold release for easy peeling from the adhesive. Since the agent is generally applied, the pellicle frame may be detached from the protective film due to vibration during transportation.
In order to prevent this, if a heavy release type is used as the release agent for the protective film, the adhesive will be deformed when the protective film is peeled from the adhesive, and the deformation will be caused when the pellicle is attached to the mask. There is a problem that the portion does not stick to the mask and an air path is generated.

Japanese Utility Model Publication No. 6-45965 JP 2000-173887 A JP-A-11-052553

  The present invention has been made in view of the above problems, and its purpose is to prevent foreign matter from adhering to the pellicle to be stored during storage, transportation, and operation, and to prevent the pellicle from being soiled and to improve the quality. An object is to provide a pellicle storage container for photolithography that can be maintained.

In order to solve the above problems, the present invention provides a pellicle storage container comprising a container main body on which a pellicle is placed, and a lid body that covers the pellicle and is fitted and locked at the periphery of the container main body. The pellicle is held by inserting a frame holding pin into a hole provided on the side surface. The container body is made of resin, and metal parts are joined to the container body. The positioning parts for positioning the frame holding pins for holding the pellicle and the metal parts assembled to the container body are mechanical. It is desirable that the elastic body is installed at the contact portion of the frame holding pin that holds the pellicle with the pellicle frame, and the material of the container body and the lid body is resin, It is further preferable that the surface resistance value has an antistatic performance of 1 × 10 ¹² Ω / □ or less.

According to the present invention, while reliably gripping the pellicle frame, it is possible to reduce the possibility of dust generation by reducing the contact portion as much as possible, and by installing the frame holding pin on the container body with increased rigidity, It has the effect of reducing the impact on the pellicle. Furthermore, according to the embodiment in which the container main body is a resin and the metal part is joined to the container main body, the resin having the advantage of light weight has an effect of covering the deformation that is a drawback, and is necessary. Only the portion can have a shape retaining function against external force.
According to the embodiment in which the part for positioning the frame holding pin for holding the pellicle and the metal part assembled to the container body are mechanically connected, the position of the pellicle is kept constant during storage, transportation, and operation. It can be kept, dust generation and deformation can be reduced.

Further, according to the embodiment in which the elastic body is installed at the contact portion between the frame holding pin for holding the pellicle and the pellicle frame, it is possible to reduce the influence of vibration on the pellicle during storage, transportation, and operation.
According to the embodiment in which the material of the container main body and the lid is resin, and the surface resistance value imparts antistatic performance of 1 × 10 ¹² Ω / □ or less, packaging that is particularly problematic in large liquid crystal pellicle storage containers The effect of preventing foreign matter adhesion such as preventing static electricity caused by friction with the bag can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.
FIG. 1 is a cross-sectional explanatory view showing an embodiment of a pellicle storage container according to the present invention, and FIG. 2 is a partially enlarged view thereof.
FIG. 3 is an explanatory view of the surface of the container body according to the embodiment of the pellicle storage container according to the present invention, and FIG. 4 is an explanatory view of the back surface of the container body.
In FIG. 1, the pellicle storage container of the present invention includes a container body 1, a lid body 2, a frame holding pin 3, a pin fixing part 4, and a reinforcing metal part 5.
Similar to the conventional pellicle storage container, by placing a stepped table on the center of the container body 1 and placing the pellicle, the container body 1 is covered with the lid body 2 fitted and locked at the peripheral edge of each other. A closed space is formed.

For the material of the container body and the lid, it is preferable to use a resin in consideration of the weight reduction of the entire container, but in the case of a large pellicle for liquid crystal, the deformation of the resin has a great influence on the product, and the container body In order to reduce the warpage of 1, the reinforcing metal part 5 is joined to the back surface of the container body 1.
In order to prevent the pellicle from being charged and causing dust to adhere to the pellicle, it is preferable that the resin used for the container main body 1 and the lid body 2 is provided with antistatic performance. As the antistatic performance, the surface resistance value is preferably 1 × 10 ¹² Ω / □ or less.
The material of the resin is not particularly limited, but acrylic resin, polyethylene terephthalate resin, acrylonitrile / butadiene / styrene resin, polystyrene resin, polycarbonate resin, vinyl chloride resin, polypropylene resin, polyethylene resin, acrylonitrile / ethylene / styrene may be used. .
The antistatic method may be selected from a method in which a hydrophilic polymer is added to the base polymer, coating of a conductive film, kneading of a conductive material, and the like if there is no problem in dust generation.

Examples of the metal material include aluminum, stainless steel, carbon steel, copper, brass, and the like, and aluminum is preferable in consideration of specific gravity and elastic modulus.
As shown in an enlarged view in FIG. 2, the pellicle frame 6 is fixed by inserting the frame holding pins 3 into the jig holes 10 provided on the outer surface of the frame. In order to grip the pellicle frame more flexibly, it is preferable to install the elastic body 8 at the tip of the frame holding pin 3.
The pin fixing part 4 is a part for positioning the frame holding pin 3. By mechanically connecting the reinforcing metal part 5 on the back surface of the container body with a screw or the like, the container by force or heat deformation from the outside of the container is used. It is possible to maintain the positional accuracy of the frame holding pin even when the main body is twisted.

Examples of the elastic material include nitrile rubber, styrene rubber, silicone rubber, fluorine rubber, chloroneprene rubber, polyurethane rubber, tetrafluoroethylene resin, polyacrylic rubber, and ethylene propylene rubber. Silicon rubber and tetrafluoroethylene rubber are preferred. In order to prevent static electricity, it is better to add an antistatic function to these materials.
Three or more locations for fixing the pellicle frame 6 with the frame holding pins 3 are required, and four or more locations including the vicinity of the corner of the pellicle frame 6 are preferable as shown in FIG.

  As shown in the plan view of the back surface of the container body in FIG. 4, the reinforcing metal component 5 is installed on the back surface of the container body in order to prevent deformation of the container body 1. The reinforcing metal part 5 is preferably mechanically connected to the pin fixing part 4. The effect can be expected even if the reinforcing metal part 5 is used alone, but a higher effect can be obtained by connecting it vertically and horizontally as shown in the figure.

Examples of the present invention will be described below, but the present invention is not limited thereto.
[Example]
The pellicle storage container shown in FIGS. 1 to 4 was manufactured.
The structure of the pellicle storage container is mainly composed of a container body 1 in which an antistatic ABS resin (trade name: Toyolac Parel TP10 manufactured by Toray Industries, Inc., surface resistance value 5 × 10 ¹¹ Ω / □) is molded by vacuum molding. Similarly, it is composed of a container lid 2 formed by vacuum forming an antistatic ABS resin (trade name: Toyolac Parel TP10, manufactured by Toray Industries, Inc., surface resistance value 5 × 10 ¹¹ Ω / □). On the back surface of the container main body, a reinforcing metal part 5 made of aluminum alloy having a cross section of 40 × 6 mm was installed, and as shown in FIG. 4, the five reinforcing metal parts 5 crossed vertically and horizontally and connected.
Further, the pin fixing part 4 installed on the surface of the container body and the reinforcing metal part 5 installed on the back surface of the container body were mechanically connected with M4 screws across the container body. Further, the material of the pin fixing component 4 and the frame holding pin 3 is made of PPS. As shown in FIG. 3, the frame holding pin 3 is provided at four locations near the corner of the pellicle frame 6, and the tip of the frame holding pin 3 is provided. Is provided with an elastic body 8 made of fluororubber.

  A silicone adhesive (trade name: KR120 manufactured by Shin-Etsu Chemical Co., Ltd.) was used as a pellicle film adhesive on one end face of an aluminum alloy pellicle frame 6 having an outer dimension of 782 × 474 × 6 mm. ), A silicone adhesive (trade name: KR120, manufactured by Shin-Etsu Chemical Co., Ltd.) is applied to the other end face as a mask adhesive, cured by heating, and further a fluoropolymer (trade name Cytop, Asahi Glass Co., Ltd.). The pellicle film 7 having a thickness of about 4 μm obtained by the spin coating method is housed on the pellicle frame 6, and the foreign matter on the pellicle film before and after transportation is increased by reciprocating between Tokyo and Fukuoka. The number was measured.

  Taking out the pellicle from the pellicle storage container in a Class 100 clean room and irradiating 400,000 lux of light in the dark room and examining the number of foreign particles increased on the surface of the pellicle film 7, no foreign particles increased on the pellicle film 7, In addition, there was no deformation or damage of the parts constituting the pellicle. Further, the charge amount of the pellicle film after transportation was measured by ION SYSTEM / MODEL775 manufactured by ION SYSTEM (California, USA), and it was -0.1 kV.

[Comparative example]
As shown in FIG. 5, a pellicle storage container having a configuration in which the upper end surface of a conventionally known pellicle frame 6 is pressed by the lid body wall 2 was manufactured. The container body 1 and the lid 2 were made of an acrylic resin having a surface resistance value of 10 ¹⁸ Ω / □ or more.

  In this pellicle storage container, a silicone adhesive (trade name: KR120 manufactured by Shin-Etsu Chemical Co., Ltd.) as a pellicle film adhesive on one end surface of an aluminum alloy pellicle frame 6 having an outer dimension of 782 × 474 × 6 mm, On the other end face, a silicone adhesive (trade name: KR120 manufactured by Shin-Etsu Chemical Co., Ltd.) is applied as a mask adhesive, cured by heating, and further a fluoropolymer (trade name Cytop, manufactured by Asahi Glass Co., Ltd.). The pellicle film 7 having a thickness of about 4 μm obtained by spin coating is affixed to the pellicle frame 6 and is transported between Tokyo and Fukuoka by reciprocating to increase the number of foreign particles on the pellicle film before and after transportation. Measured.

  When the pellicle was taken out from the pellicle storage container in a Class 100 clean room and irradiated with 400,000 lux light in the dark room to examine the increase in the number of foreign particles on the surface of the pellicle film 7, foreign particles of 10 μm or more were found on the pellicle film 7. The number of the crimps increased by 48, and a pressure-bonding mark that was not present before the transportation was observed in the portion that was in contact with the lid of the pellicle film adhesive. Moreover, when the charge amount of the pellicle film after transport was measured by ION SYSTEM / MODEL 775, it was shown to be charged at −3.8 kV.

  As described above, according to the present invention, it is possible to prevent foreign matter from adhering to the pellicle stored during storage, transportation, and operation, and to prevent the pellicle from being soiled and maintain the quality.

It is a section explanatory view showing one embodiment of a pellicle storage container by the present invention. It is the elements on larger scale which show the frame holding | maintenance part of one Embodiment of the pellicle storage container by this invention. It is a figure explaining the surface of the container main body of one Embodiment of the pellicle storage container by this invention, (a) is surface explanatory drawing, (b) is a cross-sectional explanatory drawing of a container main body. It is a figure explaining the back surface of the container main body of one Embodiment of the pellicle storage container by this invention, (a) is sectional explanatory drawing of a container main body, (b) is back surface explanatory drawing. It is explanatory drawing which shows the conventional pellicle storage container.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container body 2 Lid 3 Frame holding pin 4 Pin fixing part 5 Reinforced metal part 6 Pellicle frame 7 Pellicle membrane 8 Elastic body 9 Connecting screw 10 Frame jig hole

Claims (5)

In a pellicle storage container comprising a container main body on which a pellicle is placed and a lid body that covers the pellicle and that engages and locks at the periphery of the container main body, a frame holding pin is provided in a hole provided on the outer surface of the pellicle frame A pellicle storage container which is inserted to hold a pellicle. The pellicle storage container according to claim 1, wherein the container body is a resin, and metal parts are joined to the container body. The pellicle storage container according to claim 1 or 2, wherein a positioning part for positioning the frame holding pin for holding the pellicle and the metal part assembled to the container body are mechanically connected. The pellicle storage container according to any one of claims 1 to 3, wherein an elastic body is installed at a contact portion between the frame holding pin that holds the pellicle and the pellicle frame. The pellicle storage according to any one of claims 1 to 4, wherein the container main body and the lid are made of resin and have a surface resistance value of 1 x 10 ¹² Ω / □ or less. container.

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