Pellicle frame with mask adhesive layer, pellicle, method for producing pellicle frame with mask adhesive layer and method for producing pellicle

Abstract

To provide a pellicle frame with a mask adhesive layer in which a width of an adhesive layer forming surface of a pellicle frame is narrow and a protrusion of a mask adhesive layer from each side constituting a pellicle frame is suppressed even when a mask adhesive layer is thick.SOLUTION: The pellicle frame with a mask adhesive layer as disclosed herein includes a pellicle frame and a mask adhesive layer. The pellicle frame has an adhesive layer formation surface where the mask adhesive layer is formed. The width of each side composing the pellicle frame is 4.6 mm or less. A thickness of the mask adhesive layer in the height direction of the pellicle frame is 500 μm or more. The area of the protruding part of the mask adhesive layer is 0.10 mm2 or less. The protruding part indicates the areas where the mask adhesive layer extends from each side constituting the pellicle frame when observing the mask adhesive layer with a pellicle frame at 50 times magnification from the side where the mask adhesive layer is not formed in the height direction of the pellicle frame, across the entire circumference of the pellicle frame.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a pellicle frame with a mask adhesive layer, a pellicle, a method for manufacturing a pellicle frame with a mask adhesive layer, and a method for manufacturing a pellicle.

Background Art

[0002] The manufacturing process of a semiconductor device includes a lithography process of irradiating light onto a semiconductor wafer to form a pattern. In the lithography process, for example, light (also referred to as "exposure light") is irradiated onto a pattern formed on a rectangular photomask substrate, and the exposure light transmitted or reflected by the photomask substrate is imaged on the semiconductor wafer to expose the resist agent on the semiconductor wafer. Thereby, a predetermined pattern is transferred onto the semiconductor wafer.

[0003] In the lithography process, a pellicle is used to prevent foreign matter from adhering to the pattern formed on the photomask substrate. The pellicle is attached onto the photomask substrate and surrounds the pattern formed on the photomask substrate. Usually, the pellicle includes a pellicle frame and a pellicle film. The pellicle frame is arranged to surround the outside of the pattern region formed on the photomask substrate. The pellicle film is stretched over the pellicle frame.

[0004] Patent Document 1 discloses a mask structure. The mask structure includes a specific mask substrate, a specific frame, and a protective body (hereinafter also referred to as "pellicle film"). The frame has a frame body (hereinafter also referred to as "pellicle frame") and a self-adhesive resin (hereinafter also referred to as "mask adhesive layer"). The pellicle frame holds the pellicle film. The mask adhesive layer has flexibility. The mask adhesive layer fixes the frame body and the mask substrate. The thickness of the frame is less than or equal to half of the total thickness of the frame. In other words, the thickness of the mask adhesive layer is greater than or equal to half of the height of the pellicle frame.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 Japanese Patent Application Laid-Open No. 2006-119477 Summary of the Invention Problems to be Solved by the Invention

[0006] In the exposure process, exposure is performed while rapidly moving a photomask substrate with a pellicle attached thereto. Therefore, a lightweight pellicle is required. Specifically, a pellicle in which the width of each side constituting the pellicle frame (hereinafter also referred to as "frame width") is narrow (that is, a pellicle having a frame width of 4.6 mm or less) is required.

[0007] In the height direction of the pellicle, if the ratio of the height of the mask adhesive layer to the height of the pellicle frame and the thickness of the mask adhesive layer (that is, the ratio of the soft portion) is low, there is a risk that distortion may occur in the photomask substrate. Therefore, from the viewpoint of reducing the distortion of the photomask substrate, a pellicle having a thick mask adhesive layer (that is, a mask adhesive layer of 500 μm or more) is required. When the distortion of the photomask substrate after attachment is small, deformation of the pattern drawn on the photomask surface during exposure can be reduced.

[0008] However, if the width of the adhesive layer formation surface of the pellicle frame is narrow and the mask adhesive layer is thick, the mask adhesive layer may protrude from each side constituting the pellicle frame. Hereinafter, the portion of the mask adhesive layer protruding from each side constituting the pellicle frame is also referred to as "protruding portion". If the protruding portion of the mask adhesive layer is large, there is a risk that the following problems caused by the mask adhesive layer may easily occur.

[0009] Specifically, if the protruding portion of the mask adhesive layer is large, when the pellicle is attached to the photomask substrate, the protruding portion of the mask adhesive layer is likely to be exposed on the pattern side of the photomask substrate. When the exposed light hits the protruding portion, the protruding portion may decompose and generate gas. As a result, foreign matter derived from the gas may adhere to the pattern formed on the photomask substrate. Furthermore, when the exposed light hits the protruding portion, the exposed light may be reflected. As a result, there is a possibility that a desired pattern cannot be formed on the semiconductor wafer.

[0010] When the pellicle is placed on the photomask substrate, the pellicle is usually held and transported by the gripping portion of the placement device. If the mask adhesive layer has a protruding portion, the protruding portion of the mask adhesive layer may adhere to the gripping portion of the placement device. That is, there is a possibility that the handling of the placement device is reduced.

[0011] The present disclosure is in view of the above circumstances. The problem to be solved by one embodiment of the present disclosure is to provide a pellicle frame with a mask adhesive layer, a pellicle, a method for manufacturing a pellicle frame with a mask adhesive layer, and a method for manufacturing a pellicle, in which the width of the adhesive layer formation surface of the pellicle frame is narrow, and even if the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed.

Means for Solving the Problem

[0012] The means for solving the above problems include the following embodiments. <1> A pellicle frame with a mask adhesive layer, comprising a pellicle frame and a mask adhesive layer for attaching the pellicle frame to a photomask substrate, wherein the pellicle frame has an adhesive layer formation surface on which the mask adhesive layer is formed at one end in the height direction of the pellicle frame, the width of each side constituting the pellicle frame is 4.6 mm or less, the thickness of the mask adhesive layer in the height direction of the pellicle frame is 500 μm or more, The area of the protruding part of the mask adhesive layer is 0.10 mm 2 or less, when the protruding part is observed at a magnification of 50 times the mask adhesive layer - attached pellicle frame from the side where the mask adhesive layer is not formed in the height direction of the pellicle frame, the mask adhesive layer - attached pellicle frame showing the parts protruding from each side constituting the pellicle frame among the mask adhesive layers over the entire circumference of the pellicle frame. <2> The adhesive layer formation surface is a plane orthogonal to the height direction of the pellicle frame, The width of the adhesive layer formation surface is 2.0 mm or less, the mask adhesive layer - attached pellicle frame according to <1>. <3> The thickness ratio of the mask adhesive layer is 5% - 30%, The thickness ratio indicates the ratio of the thickness of the mask adhesive layer to the total value of the thickness of the mask adhesive layer and the height of the pellicle frame, the mask adhesive layer - attached pellicle according to <1> or <2>. <4> The mask adhesive layer - attached pellicle frame according to any one of <1> to <3>, and a pellicle film stretched at the other end in the height direction of the pellicle frame of the pellicle frame, A pellicle comprising. <5> A manufacturing method for manufacturing the mask adhesive layer - attached pellicle frame according to any one of <1> to <3>, Preparing the pellicle frame, Polymerizing raw materials to produce a main agent containing a copolymer (a), Adding a cross - linking agent (b) to the main agent to produce a coating composition, Coating the coating composition on the adhesive layer formation surface of the pellicle frame, Curing the coating composition coated on the adhesive layer formation surface to produce the mask adhesive layer, Having, A manufacturing method for a mask adhesive layer - attached pellicle frame, wherein the viscosity of the coating composition is 200 Pa·s or more. <6> A manufacturing method for manufacturing the mask adhesive layer - attached pellicle frame according to any one of <1> to <3>, preparing the pellicle frame; polymerizing a raw material to produce a main agent containing a copolymer (a); adding a crosslinking agent (b) to the main agent to produce a coating composition; coating the coating composition on the adhesive layer forming surface of the pellicle frame; curing the coating composition coated on the adhesive layer forming surface to produce the mask adhesive layer; having; A method for manufacturing a pellicle frame with a mask adhesive layer, wherein the weight average molecular weight of the copolymer (a) contained in the main agent is 300,000 or more. <7> A manufacturing method for manufacturing the pellicle frame with a mask adhesive layer according to any one of <1> to <3>, preparing the pellicle frame; polymerizing a raw material containing a polymerization initiator to produce a main agent containing a copolymer (a); adding a crosslinking agent (b) to the main agent to produce a coating composition; coating the coating composition on the adhesive layer forming surface of the pellicle frame; curing the coating composition coated on the adhesive layer forming surface to produce the mask adhesive layer; having; the polymerization initiator ratio is 400 to 2000, A method for manufacturing a pellicle frame with a mask adhesive layer, wherein the polymerization initiator ratio represents the ratio of the number of moles of all monomers used in the copolymer (a) to the number of moles of the polymerization initiator. <8> preparing a pellicle film; producing the pellicle frame with a mask adhesive layer by the manufacturing method of the pellicle frame with a mask adhesive layer according to any one of <5> to <7>; stretching the pellicle film at the other end in the height direction of the pellicle frame; having;

Advantages of the Invention

[0013] According to an embodiment of the present disclosure, there can be provided a pellicle frame with a mask adhesive layer, a pellicle, a method for manufacturing a pellicle frame with a mask adhesive layer, and a method for manufacturing a pellicle, in which the width of the adhesive layer forming surface of the pellicle frame is narrow, and even if the mask adhesive layer is thick, the overhang of the mask adhesive layer from each side constituting the pellicle frame is suppressed.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0015] In the present disclosure, the numerical range indicated by using "~" means a range including the numerical values described before and after "~" as the minimum value and the maximum value, respectively. In the numerical ranges described step by step in the present disclosure, the upper limit value or the lower limit value described in a certain numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described in other step-by-step descriptions. Also, in the numerical ranges described in the present disclosure, the upper limit value or the lower limit value described in a certain numerical range may be replaced with the value shown in the examples. In the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment. In the present disclosure, the amount of each component means the total amount of a plurality of substances corresponding to each component, unless otherwise specified when there are a plurality of types of substances corresponding to each component. In this specification, the term "step" includes not only an independent step, but also a step that cannot be clearly distinguished from other steps, as long as the intended purpose of the step is achieved.

[0016] Hereinafter, with reference to the drawings, a pellicle frame with a mask adhesive layer, a pellicle, a method for manufacturing a pellicle frame with a mask adhesive layer, and a method for manufacturing a pellicle according to an embodiment of the present disclosure will be described. In the drawings, the same or corresponding parts are denoted by the same reference numerals and the description will not be repeated.

[0017] (1) Perforated frame with mask adhesive layer The perforated frame with a mask adhesive layer of the present disclosure includes a perforated frame and a mask adhesive layer for attaching the perforated frame to a photomask substrate. The perforated frame has an adhesive layer formation surface on one end in the height direction of the perforated frame (hereinafter, also simply referred to as the "height direction") where the mask adhesive layer is formed. The width of each side constituting the perforated frame (hereinafter, also referred to as the "frame width") is 4.6 mm or less. The thickness of the mask adhesive layer in the height direction of the perforated frame (hereinafter, also simply referred to as the "thickness") is 500 μm or more. The area of the protruding portion of the mask adhesive layer is 0.10 mm 2 or less. The protruding portion indicates a portion that protrudes from each side constituting the perforated frame of the mask adhesive layer over the entire circumference of the perforated frame when the perforated frame with the mask adhesive layer is observed at a magnification of 50 times from the side where the mask adhesive layer is not formed in the height direction of the perforated frame.

[0018] The method for measuring the area of the protruding portion of the mask adhesive layer is the same as the method described in the examples.

[0019] Since the perforated frame with a mask adhesive layer of the present disclosure has the above configuration, even if the width of the adhesive layer formation surface of the perforated frame is narrow and the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the perforated frame is suppressed. In the present disclosure, the width of each side constituting the perforated frame is 4.6 mm or less. Thereby, the perforated film using the perforated frame with a mask adhesive layer of the present disclosure is lighter than the conventional perforated film. Therefore, the perforated frame with a mask adhesive layer of the present disclosure can reduce the load on the device that moves the photomask substrate with the perforated film attached at high speed in the exposure process. In addition, in the present disclosure, the thickness of the mask adhesive layer is 500 μm or more. When a pellicle using the pellicle frame with a mask adhesive layer of the present disclosure is attached to a photomask substrate, the distortion of the photomask substrate is smaller than that of a conventional pellicle. Therefore, the pellicle frame with a mask adhesive layer of the present disclosure can reduce errors during exposure. In the present disclosure, the area of the protruding portion of the mask adhesive layer is 0.10 mm 2 or less. As a result, when a pellicle using the pellicle frame with a mask adhesive layer of the present disclosure is attached onto a photomask substrate, the protruding portion of the mask adhesive layer is less likely to be exposed on the pattern side of the photomask substrate than a conventional pellicle. That is, during the exposure process, the exposure light is less likely to hit the mask adhesive layer. As a result, during the exposure process, gas derived from the mask adhesive layer is less likely to be generated. That is, foreign matter derived from the gas is less likely to adhere to the pattern formed on the photomask substrate. Therefore, the pellicle frame with a mask adhesive layer of the present disclosure can form a desired pattern on a semiconductor wafer. In addition, when a pellicle using the pellicle frame with a mask adhesive layer of the present disclosure is placed on a photomask substrate, the protruding portion of the mask adhesive layer is less likely to adhere to the gripping portion of the placement device. That is, the pellicle frame with a mask adhesive layer of the present disclosure can suppress a decrease in the handling of the placement device.

[0020] The pellicle frame with a mask adhesive layer is suitably used as a component of a pellicle described later.

[0021] (1.1) Pellicle Frame The pellicle frame with a mask adhesive layer of the present disclosure includes a pellicle frame.

[0022] The pellicle frame is a cylindrical object. The pellicle frame has a through-hole. The through-hole indicates a space through which the exposure that has passed through the pellicle film reaches the photomask substrate.

[0023] The pellicle frame has an adhesive layer formation surface on one end surface in the height direction of the pellicle frame (hereinafter, also referred to as "one end surface"). The adhesive layer formation surface is a plane orthogonal to the height direction of the pellicle frame.

[0024] The adhesive layer forming surface is a plane orthogonal to the height direction of the pellicle frame, and the width of the adhesive layer forming surface is preferably 2.0 mm or less. Thereby, the pellicle using the pellicle frame with a mask adhesive layer of the present disclosure is lighter in weight than the configuration in which the width of the adhesive layer forming surface exceeds 2.0 mm. Therefore, the pellicle frame with a mask adhesive layer of the present disclosure can further reduce the load on the apparatus that rapidly moves the photomask substrate with the pellicle attached thereto in the exposure process. "The adhesive layer forming surface is a plane orthogonal to the height direction of the pellicle frame" means that the adhesive layer forming surface does not include the chamfered portion described later among one end surfaces in the height direction of the pellicle frame. More preferably, the width of the adhesive layer forming surface is 1.8 mm or less. By the width of the adhesive layer forming surface being 1.8 mm or less, it becomes easier to achieve both sufficient adhesiveness between the mask adhesive layer and the photomask substrate and appropriate peelability when peeling the used pellicle frame from the photomask substrate after exposure. From the viewpoint of weight reduction of the pellicle frame with a mask adhesive layer and the like, the width of the adhesive layer forming surface is more preferably 1.7 mm or less, and particularly preferably 1.6 mm or less. From the viewpoint of ensuring sufficient adhesiveness of the mask adhesive layer, it is preferably 1.0 mm or more, and more preferably 1.2 mm or more. From these viewpoints, the width of the adhesive layer forming surface is preferably 1.0 mm to 2.0 mm.

[0025] At least one of the two edges in the width direction of one end surface of the pellicle frame may or may not be chamfered. When chamfering is performed on one end surface, the chamfering may be performed on the entire circumference of the adhesive layer forming surface of the pellicle frame, or may be performed on a part of the adhesive layer forming surface of the pellicle frame. The chamfering is not particularly limited, and examples thereof include C chamfering, R chamfering, and the like.

[0026] The shape of the pellicle frame corresponds to the shape of the photomask substrate. The shape of the pellicle frame as viewed from the height direction is not particularly limited, and examples thereof include a rectangular frame shape (for example, a rectangular frame shape, a square frame shape, etc.).

[0027] The rectangular frame-shaped pellicle frame is composed of four sides when viewed from the height direction of the pellicle frame. The four sides have a pair of long sides and a pair of short sides. The length of the long side of the pellicle frame is preferably 200 mm or less. The length of the short side of the pellicle frame can be, for example, 5 mm to 180 mm, preferably 80 mm to 170 mm, more preferably 100 mm to 160 mm. The height of the pellicle frame is not particularly limited, preferably 9.0 mm or less, more preferably 8.0 mm or less. When the frame width varies depending on the location around the entire circumference of the pellicle frame, the "frame width of the pellicle frame" indicates the smallest frame width around the entire circumference of the pellicle frame.

[0028] The pellicle frame may or may not have ventilation holes. The ventilation holes communicate the internal space of the pellicle and the external space of the pellicle when the pellicle frame is attached to the photomask substrate. The "internal space of the pellicle" refers to the space surrounded by the pellicle and the photomask substrate. The "external space of the pellicle" refers to the space not surrounded by the pellicle and the photomask substrate.

[0029] Examples of the material of the pellicle frame include aluminum, titanium, stainless steel, ceramic-based materials (such as silicon or glass, etc.), or resins (such as polyethylene, etc.).

[0030] (1.2) Mask adhesive layer The pellicle frame with a mask adhesive layer of the present disclosure includes a mask adhesive layer.

[0031] The mask adhesive layer is a gel-like viscoelastic body. The mask adhesive layer has viscosity and cohesive force. "Viscosity" refers to the property of a liquid that contacts and wets the adherend, which is the photomask substrate. "Cohesive force" refers to the property of a solid that resists peeling from the photomask substrate.

[0032] (1.2.1) Thickness The thickness of the mask adhesive layer is 500 μm or more. From the viewpoint of reducing the distortion of the photomask substrate after attachment, the thickness of the mask adhesive layer is preferably 530 μm or more, more preferably 550 μm or more. From the viewpoint of the height restriction as the pellicle frame set in the exposure apparatus, the thickness of the mask adhesive layer is preferably 1000 μm or less, more preferably 600 μm or less. From these viewpoints, the thickness of the mask adhesive layer is 500 μm to 1000 μm.

[0033] As a method for adjusting the thickness of the mask adhesive layer to 500 μm or more, it is necessary to increase the viscosity of the coating composition. In order to increase the viscosity, examples include increasing the molecular weight of the polymer (for example, (meth)acrylic acid alkyl ester copolymer, etc.) contained in the coating composition and / or increasing the polymer concentration. As a method for increasing the molecular weight, adding a predetermined amount of crosslinking agent and curing it, etc. are effective. As an apparatus for accurately coating a high-viscosity coating composition on a pellicle frame, a dispenser of a specific method (for example, air pulse method, jet method, volumetric metering method, screw method, or tubing method, etc.) can be used. Preferred apparatuses include, for example, a dispenser equipped with a rotary volumetric mono pump.

[0034] The thickness ratio of the mask adhesive layer is preferably 5% to 30%. The thickness ratio indicates the ratio of the thickness of the mask adhesive layer to the total value of the thickness of the mask adhesive layer and the height of the pellicle frame. When the thickness ratio of the mask adhesive layer is 5% to 30%, the pellicle using the pellicle with a mask adhesive layer of the present disclosure can reduce the distortion of the photomask substrate due to the flexibility exhibited by the mask adhesive layer while ensuring sufficient adhesiveness to the photomask substrate. The thickness ratio of the mask adhesive layer may be 10% or more, and may be 15% or more. The thickness ratio of the mask adhesive layer may be 28% or less, and may be 25% or less.

[0035] (1.2.2) Width In the width direction of the adhesive layer forming surface (hereinafter also simply referred to as the "width direction"), the width of the mask adhesive layer tends to be the largest at the central part in the height direction of the mask adhesive layer. In the height direction, the width of the mask adhesive layer tends to be the smallest at the portion where the mask adhesive layer contacts the photomask substrate (hereinafter also referred to as the "mask contact portion"). The mask contact portion of the mask adhesive layer is a plane orthogonal to the height direction of the pellicle frame.

[0036] The maximum length in the width direction of the mask adhesive layer (hereinafter also referred to as the "adhesive width") is such that the area of the overhanging portion of the mask adhesive layer is 0.10 mm 2 The following is not particularly limited as long as it is below. The adhesive width may be 1.9 mm or less, or may be 1.8 mm or less. The adhesive width is preferably 0.9 mm or more. More preferably, it is 1.1 mm or more.

[0037] The length in the width direction of the mask contact portion of the mask adhesive layer (hereinafter also referred to as the "mask contact width") is smaller than the adhesive width. The mask contact width may be 1.6 mm or less, or may be 1.5 mm or less. The mask contact width is preferably 0.9 mm or more, and more preferably 1.1 mm or more, in order to ensure sufficient adhesiveness with the photomask substrate and to ensure the airtightness within the pellicle frame.

[0038] (1.2.3) Overhanging portion The area of the overhanging portion of the mask adhesive layer is 0.10 mm 2 The following. The area of the overhanging portion of the mask adhesive layer is preferably 0.05 mm or less, and more preferably 0.02 mm or less, from the viewpoints of making it difficult to generate gas by exposure light and making it difficult for the mask adhesive layer to adhere to the gripping portion of the placement device. 2 The following. 2 The following.

[0039] The area of the overhanging portion of the mask adhesive layer is 0.10 mm 2As methods for adjustment described below, there are optimizing the coating path of the dispenser (for example, moving the dispenser nozzle so that the dispenser nozzle passes through the central portion in the width direction of the adhesive layer forming surface over the entire circumference of the pellicle frame, etc.), increasing the viscosity of the coating composition so that the coating of the coating composition does not flow down from the edge of the adhesive layer forming surface, and the like. As methods for increasing the viscosity of the coating composition, there are increasing the molecular weight of the polymer contained in the coating composition and / or increasing the concentration, etc. As a method for increasing the molecular weight of the polymer, adding a predetermined amount of a crosslinking agent to the coating composition and curing the coating of the coating composition, and the like can be mentioned.

[0040] (1.2.4) Glass transition temperature The glass transition temperature Tg of the mask adhesive layer is not particularly limited, and it is preferably more than -25°C and less than 10°C. Thereby, the mask adhesive layer has an adhesive force in the use temperature range of the pellicle (for example, 20°C or higher), and even when exposed to a high temperature environment, the pellicle is less likely to peel from the photomask substrate. From the viewpoint of making the pellicle less likely to peel from the photomask substrate even when exposed to a high temperature environment, the glass transition temperature Tg of the mask adhesive layer is more preferably -22°C or higher, further preferably -20°C or higher, and most preferably -18°C or higher. From the viewpoint of imparting adhesiveness at room temperature, the glass transition temperature Tg of the mask adhesive layer is more preferably 5°C or lower, and further preferably 0°C or lower. The glass transition temperature (Tg) of the mask adhesive layer is a method in accordance with JIS K7121.

[0041] (1.2.5) Material The mask adhesive layer is composed of an adhesive composition. The adhesive composition is not particularly limited, and examples thereof include acrylic adhesives, silicone adhesives, styrene-butadiene adhesives, urethane adhesives, or olefin adhesives. Among them, from the viewpoint of reducing the outgas generation amount generated from the pellicle, etc., the adhesive composition is preferably an acrylic adhesive. Details of the material of the mask adhesive layer will be described in the manufacturing method of the pellicle frame with a mask adhesive layer.

[0042] (1.2.6) Resin mass The resin mass of the mask adhesive layer is not particularly limited, and is preferably 450 mg to 560 mg. The resin mass of the mask adhesive layer indicates the high-thickness state of the mask adhesive layer when the mask adhesive layer is coated with a constant thickness over the entire one end of the pellicle frame. If the resin mass of the mask adhesive layer is 450 mg to 560 mg, both mask distortion suppression and protrusion suppression can be achieved simultaneously. From the viewpoint of ensuring high thickness, the resin mass of the mask adhesive layer is more preferably 460 mg or more, and even more preferably 470 mg or more. From the viewpoint of suppressing protrusion, the resin mass of the mask adhesive layer is more preferably 540 mg or less, and even more preferably 530 mg or less. The method for measuring the resin mass is the same as the method described in the examples.

[0043] (1.3) Protective film The pellicle frame with a mask adhesive layer of the present disclosure may or may not include a protective film (i.e., a liner).

[0044] The protective film protects the mask contact portion of the mask adhesive layer. The protective film is peelable from the mask adhesive layer. The thickness of the protective film is preferably 5 μm to 500 μm, and more preferably 30 μm to 200 μm. Examples of the material of the protective film include polyester. A release agent may be applied to the surface of the protective film that contacts the mask adhesive layer. Examples of the release agent include silicone-based release agents and fluorine-based release agents.

[0045] (1.4) An example of a pellicle frame with a mask adhesive layer Next, with reference to FIGS. 1 and 2, a pellicle with a mask adhesive layer according to an embodiment of the present disclosure will be described. FIG. 1 is a top view of a pellicle frame 1 with a mask adhesive layer according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1.

[0046] As shown in FIG. 1, the pellicle frame 1 with a mask adhesive layer has a pellicle frame 11 and a mask adhesive layer 12 (see FIG. 2). The pellicle frame 11 is a rectangular frame. The pellicle frame 11 has a pair of long sides 111 and a pair of short sides 112. Note that the pellicle frame 11 may be a square frame, a circular frame, or an elliptical frame.

[0047] In this embodiment, the direction in which the long side 111 of the pellicle frame 11 extends is defined as the X-axis direction, the direction in which the short side 112 of the pellicle frame 11 extends is defined as the Y-axis direction, and the height direction of the pellicle frame 11 is defined as the Z-axis direction. Each of the X-axis, Y-axis, and Z-axis is perpendicular to each other. The Z-axis is an example of the height direction of the pellicle frame 11. Note that these directions do not limit the directions during the use of the pellicle with a mask adhesive layer of the present disclosure.

[0048] (1.4.1) Pellicle Frame The pellicle frame 11 is a cylindrical object. The pellicle frame 11 has a through-hole TH.

[0049] As shown in FIG. 2, the pellicle frame 11 has one end face S11A on the negative Z-axis side. The one end face S11A of the pellicle frame 11 has an adhesive layer formation surface S11A1 and two chamfered surfaces S11A2. The adhesive layer formation surface S11A1 is a plane perpendicular to the height direction (Z-axis direction) of the pellicle frame 11. The chamfered surfaces S11A2 are formed at both edges in the width direction (X-axis direction) of the one end face S11A of the pellicle frame 11.

[0050] The width L1 (the length L1 in the X-axis direction) (see FIG. 2) of the adhesive layer formation surface S11A1 is 2.0 mm or less, preferably less than 2.0 mm, and more preferably 1.8 mm or less. Note that the width L1 may be more than 2.0 mm.

[0051] The pellicle frame 11 has the other end face S11B on the positive Z-axis side. A pellicle film is stretched on the other end face S11B of the pellicle frame 11.

[0052] The length L11 of the long side 111 of the pellicle frame 11 (the length L11 in the X-axis direction) (see FIG. 1) is 200 mm or less. The length L12 of the short side 112 of the pellicle frame 11 (the length L12 in the Y-axis direction) (see FIG. 1) is 5 mm to 180 mm. The height L13 of the pellicle frame 11 (the length L13 in the Z-axis direction) (see FIG. 2) is 3.0 mm or less. The frame width L14 of the pellicle frame 11 (see FIG. 2) is 4.6 mm or less, preferably less than 2 mm. Note that the length L11 may be more than 200 mm. The length L12 may be outside the range of 5 mm to 180 mm. The height L13 may be more than 3.0 mm.

[0053] (1.4.2) Mask adhesive layer The mask adhesive layer 12 is formed on the adhesive layer formation surface S11A1 of the pellicle frame 11. The mask adhesive layer 12 has a mask contact portion R120. The mask contact portion R120 is a plane orthogonal to the height direction (Z-axis direction) of the pellicle frame 11.

[0054] The thickness L2 of the mask adhesive layer 12 (the length L2 in the Z-axis direction) (see FIG. 2) is 500 μm or more. The adhesive width L3 of the mask adhesive layer 12 (the length L3 in the X-axis direction) (see FIG. 2) is 0.9 mm to 1.9 mm. The mask contact width L4 of the mask contact portion R120 of the mask adhesive layer 12 is 0.9 mm to 1.6 mm. Note that the adhesive width L3 may be outside the range of 0.9 mm to 1.9 mm. The mask contact width L4 may be outside the range of 0.9 mm to 1.6 mm.

[0055] The area of the protruding portion R12 of the mask adhesive layer 12 is 0.10 mm 2 or less. The protruding portion R12 indicates a portion that protrudes from each side (that is, each of the pair of long sides 111 and the pair of short sides 112) constituting the pellicle frame 11 in the entire circumference of the pellicle frame 11 when the pellicle frame 11 with the mask adhesive layer is observed at a magnification of 50 times from the side where the mask adhesive layer 12 is not formed in the Z-axis direction (the height direction of the pellicle frame 11).

[0056] The thickness ratio of the mask adhesive layer 12 is preferably 5% to 30%. The thickness ratio indicates the ratio of the thickness L2 of the mask adhesive layer 12 (see Fig. 2) to the total value of the thickness L2 of the mask adhesive layer 12 and the height L13 of the pellicle frame 11 (see Fig. 2).

[0057] (1.4.1) Function and effect As described with reference to Figs. 1 and 2, the pellicle frame 1 with a mask adhesive layer includes a pellicle frame 11 and a mask adhesive layer 12. The pellicle frame 11 has an adhesive layer forming surface S11A1 at one end in the height direction of the Z-axis direction of the pellicle frame 11. The frame width L14 of the pellicle frame 11 is 4.6 mm or less. The thickness L2 of the mask adhesive layer 12 is 500 μm or more. The area of the overhanging portion R12 of the mask adhesive layer 12 is 0.10 mm 2 or less. Thereby, even when the width of the adhesive layer forming surface S11A1 of the pellicle frame 11 is narrow and the mask adhesive layer 12 is thick, the overhang of the mask adhesive layer 12 from each side constituting the pellicle frame 11 (that is, each of the pair of long sides 111 and the pair of short sides 112) is suppressed. The pellicle using the pellicle frame 1 with a mask adhesive layer is lighter than a conventional pellicle. Therefore, the pellicle frame 1 with a mask adhesive layer can reduce the load on the device that moves the photomask substrate with the pellicle attached at high speed in the exposure process. In addition, when the pellicle using the pellicle frame 1 with a mask adhesive layer is attached to the photomask substrate, the distortion of the photomask substrate is smaller than that of a conventional pellicle. Therefore, the pellicle frame 1 with a mask adhesive layer can reduce the error during exposure. When a pellicle using the pellicle frame 1 with a mask adhesive layer is attached to a photomask substrate, the protruding portion R12 of the mask adhesive layer 12 is less likely to be exposed on the pattern side of the photomask substrate than a conventional pellicle. That is, in the exposure process, the exposure light is less likely to hit the mask adhesive layer 12. As a result, during the exposure process, gas derived from the mask adhesive layer 12 is less likely to be generated. That is, foreign matter derived from the gas is less likely to adhere to the pattern formed on the photomask substrate. Therefore, the pellicle frame 1 with a mask adhesive layer can form a desired pattern on a semiconductor wafer. In addition, when the pellicle using the pellicle frame 1 with a mask adhesive layer is arranged on the photomask substrate, the protruding portion R12 of the mask adhesive layer 12 is less likely to adhere to the gripping portion of the arranging device. That is, the pellicle frame 1 with a mask adhesive layer can suppress the deterioration of the handling of the arranging device.

[0058] (2) Pellicle The pellicle of the present disclosure includes the pellicle frame with a mask adhesive layer of the present disclosure and a pellicle film. The pellicle film is stretched at the other end in the height direction of the pellicle frame of the pellicle frame.

[0059] Since the pellicle of the present disclosure has the above configuration, similar to the pellicle frame with a mask adhesive layer of the present disclosure, even if the width of the adhesive layer forming surface of the pellicle frame is narrow and the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed.

[0060] (2.1) Pellicle film The pellicle according to the embodiment includes a pellicle film. The pellicle film prevents foreign matter from adhering to the surface of the photomask substrate and transmits exposure light during exposure. The foreign matter includes dust. Examples of the exposure light include deep ultraviolet (DUV) light or EUV. EUV indicates light with a wavelength of 5 nm to 30 nm.

[0061] The pellicle film covers the entire opening on one end face side of the through-hole of the pellicle frame. The pellicle film may be directly supported on one end face of the pellicle frame, or may be supported via an adhesive layer (hereinafter, also referred to as a "film adhesive layer"). The film adhesive layer may be a cured product of a known adhesive.

[0062] The film thickness of the pellicle film is preferably 1 nm to 300 nm. The material of the pellicle film is not particularly limited, and examples thereof include cellulose-based resins, fluorine-based resins, carbon-based materials, SiN, polysilicon, or boron nitride, etc., according to the exposure light source to be used. The carbon-based material includes carbon nanotubes (hereinafter, also referred to as "CNT"). Among them, the pellicle film preferably contains a cellulose-based resin or a fluorine-based resin. The pellicle film may be a known pellicle film.

[0063] (3) Manufacturing method of the pellicle frame with a mask adhesive layer of the first embodiment The manufacturing method of the pellicle frame with a mask adhesive layer of the first embodiment of the present disclosure is a manufacturing method for manufacturing the pellicle frame with a mask adhesive layer of the present disclosure. The manufacturing method includes preparing the pellicle frame (hereinafter, also referred to as the "pellicle frame preparation step"), polymerizing raw materials to produce a main agent containing a copolymer (a) (hereinafter, the "main agent production step"), adding a cross-linking agent (b) to the main agent to produce a coating composition (hereinafter, the "coating composition production step"), applying the coating composition onto the adhesive layer forming surface of the pellicle frame (hereinafter, the "coating step"), and curing the coating composition applied onto the adhesive layer forming surface to produce the mask adhesive layer (hereinafter, the "curing step"). The viscosity of the coating composition is 200 Pa·s or more. The main agent production step, the coating composition production step, the coating step, and the curing step are carried out in this order. The pellicle frame preparation step is carried out before the coating step.

[0064] Since the method for manufacturing a pellicle frame with a mask adhesive layer according to the first embodiment has the above configuration, it is possible to manufacture a pellicle frame with a mask adhesive layer in which the width of the adhesive layer forming surface of the pellicle frame is narrow and the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed even when the mask adhesive layer is thick. According to the method for manufacturing a pellicle frame with a mask adhesive layer according to the first embodiment, in the obtained pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. As the thickness of the mask adhesive layer increases, when a certain load is applied by attaching a photomask, the mask adhesive layer is likely to be distorted, and the stress applied to the photomask is reduced under the influence. As a result, the pellicle using the pellicle frame with a mask adhesive layer according to the first embodiment can suppress the distortion of the photomask substrate when attached to the photomask substrate.

[0065] (3.1) Pellicle Frame Preparation Step In the pellicle frame preparation step, a pellicle frame is prepared.

[0066] Examples of the pellicle frame include those similar to the pellicle frame in the pellicle frame with a mask adhesive layer of the present disclosure. The method for preparing the pellicle frame may be any known method.

[0067] (3.2) Main Agent Preparation Step In the main agent preparation step, raw materials are polymerized to prepare a main agent containing the copolymer (a).

[0068] (3.2.1) Main Agent The main agent is appropriately selected according to the material of the adhesive composition constituting the mask adhesive layer, and may be any known raw material. As described above, from the viewpoint of reducing the amount of outgas generated from the pellicle, etc., the adhesive composition constituting the mask adhesive layer is preferably an acrylic adhesive.

[0069] Hereinafter, the case where the adhesive composition is an acrylic adhesive will be described.

[0070] (3.2.1.1) Copolymer (a) The copolymer (a) preferably contains a (meth)acrylic acid alkyl ester copolymer (a1), and more preferably is the (meth)acrylic acid alkyl ester copolymer (a1).

[0071] In the first embodiment, the weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is preferably 300,000 or more. Thereby, in the obtained pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. The weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is more preferably 500,000 to 2,000,000, still more preferably 600,000 to 1,500,000, and particularly preferably 700,000 to 1,200,000. If the weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is 2,000,000 or less, it is easy to adjust the viscosity of the coating composition to an appropriate viscosity. As a result, it is easy to coat the coating composition to a desired size. The weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is more preferably 1,500,000 or less, and still more preferably 1,200,000 or less. The measuring method of the weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is GPC (gel permeation chromatography), and the details of the measuring method will be described later in the examples. For example, generally, the higher the monomer concentration during the polymerization reaction, the greater the tendency for the weight average molecular weight (Mw) to be large. The lower the amount of the polymerization initiator and the lower the polymerization temperature, the greater the tendency for the weight average molecular weight (Mw) to be large. The weight average molecular weight can be controlled by adjusting the monomer concentration, the amount of the polymerization initiator, and the polymerization temperature.

[0072] The (meth)acrylic acid alkyl ester copolymer (a1) preferably includes a copolymer of a (meth)acrylic acid alkyl ester monomer and a monomer having a functional group reactive with at least one of an isocyanate group, an epoxy group, and an acid anhydride (hereinafter also referred to as "functional group-containing monomer").

[0073] (3.2.2) Raw materials The raw materials of the (meth)acrylic acid alkyl ester copolymer (a1) preferably include a (meth)acrylic acid alkyl ester monomer and a functional group-containing monomer.

[0074] (3.2.2.1) (Meth)acrylic acid alkyl ester monomer The (meth)acrylic acid alkyl ester monomer preferably includes a (meth)acrylic acid alkyl ester monomer having an alkyl group with 1 to 14 carbon atoms. Examples of the (meth)acrylic acid alkyl ester monomer having an alkyl group with 1 to 14 carbon atoms include (meth)acrylic acid ester monomers of linear aliphatic alcohols, (meth)acrylic acid ester monomers of branched-chain aliphatic alcohols, or (meth)acrylic acid ester monomers of cyclic aliphatic alcohols. Examples of the (meth)acrylic acid ester monomer of linear aliphatic alcohols include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, propyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, or lauryl (meth)acrylate. Examples of the (meth)acrylic acid ester monomer of branched-chain aliphatic alcohols include isobutyl (meth)acrylate, isoamyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, or isononyl (meth)acrylate. These may be used alone or in combination of two or more. Examples of the (meth)acrylic acid ester monomer of cyclic aliphatic alcohols include cyclohexyl (meth)acrylate or dicyclopentenyl oxyethyl (meth)acrylate.

[0075] Among these, the (meth)acrylic acid alkyl ester monomer preferably has at least one of an alkyl group with 1 to 3 carbon atoms and an alicyclic alkyl group. Hereinafter, an alkyl (meth)acrylate monomer having at least one of an alkyl group having 1 to 3 carbon atoms and an alicyclic alkyl group is also referred to as a "high Tg monomer". "Tg" refers to the glass transition temperature. In order to further reduce the amount of outgas generated, the alkyl (meth)acrylate monomer is more preferably an alkyl acrylate monomer having an alkyl group having 1 to 3 carbon atoms or an alicyclic alkyl group, and even more preferably an alkyl acrylate monomer having an alkyl group having 1 to 3 carbon atoms. When the alkyl (meth)acrylate monomer is an alkyl acrylate monomer having an alicyclic alkyl group, from the viewpoint of availability, the number of carbon atoms of the alicyclic alkyl group is preferably 5 to 10. By containing a high Tg monomer in the alkyl (meth)acrylate monomer, high peel strength can be maintained even in a high-temperature atmosphere. Specifically, examples of the high Tg monomer include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, cyclohexyl methacrylate, or dicyclopentanyl methacrylate. Among these, in order to more easily maintain high peel strength even in a high-temperature atmosphere, the alkyl (meth)acrylate monomer preferably has at least one of an alkyl group having 1 to 2 carbon atoms and an alicyclic alkyl group, and more preferably the alkyl (meth)acrylate monomer has an alkyl group having 1 to 2 carbon atoms.

[0076] The content of the alkyl (meth)acrylate monomer is preferably 80 parts by mass to 99.5 parts by mass, more preferably 85 parts by mass to 99.5 parts by mass, and even more preferably 87 parts by mass to 99.5 parts by mass with respect to 100 parts by mass of the total amount of the monomers constituting the alkyl (meth)acrylate copolymer (a1).

[0077] (3.2.2.2) Functional group-containing monomer Examples of the functional group-containing monomer include a carboxy group-containing monomer, a hydroxy group-containing monomer, an epoxy group-containing monomer, etc.

[0078] Examples of the carboxy group-containing monomer include (meth)acrylic acid, itaconic acid, (meth)acrylic acid itaconic acid, maleic acid, crotonic acid, etc. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, etc. These may be used alone or in combination of two or more. In particular, from the viewpoints of copolymerizability, versatility, etc., the functional group-containing monomer preferably includes a hydroxy group-containing (meth)acrylic acid having a hydroxyalkyl group with 2 to 4 carbon atoms or glycidyl (meth)acrylate which is an epoxy group-containing monomer. Examples of the hydroxy group-containing (meth)acrylic acid having a hydroxyalkyl group with 2 to 4 carbon atoms include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.

[0079] The content of the functional group-containing monomer is preferably, for example, 0.5 parts by mass to 20 parts by mass with respect to 100 parts by mass of the total amount of the monomers constituting the (meth)acrylic acid alkyl ester copolymer (a1).

[0080] (3.2.2.3) Polymerization solvent The raw materials may further contain a polymerization solvent. Examples of the polymerization solvent include propyl acetate, ethyl acetate, toluene, etc.

[0081] (3.2.3) Polymerization method (Meta) The polymerization method of the alkyl acrylate copolymer (a1) is not particularly limited, and examples thereof include solution polymerization, bulk polymerization, emulsion polymerization, or radical polymerization. The (meta) alkyl acrylate copolymer (a1) obtained by these polymerization methods may be any of a random copolymer, a block copolymer, or a graft copolymer.

[0082] (3.2.3.1) Solution polymerization As an example of solution polymerization, a method of adding a polymerization initiator to a mixed solution of monomers under an inert gas stream such as nitrogen and performing a polymerization reaction at 50 ° C to 100 ° C for 4 hours to 30 hours can be mentioned.

[0083] Examples of the polymerization initiator include azo-based polymerization initiators and peroxide-based polymerization initiators. Examples of the azo-based polymerization initiator include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis-2-methylbutyronitrile, dimethyl 2,2'-azobis(2-methylpropionate), or 4,4'-azobis-4-cyanovaleric acid. Examples of the peroxide-based polymerization initiator include benzoyl peroxide. The content of the polymerization initiator is preferably 0.01 parts by mass to 2.0 parts by mass with respect to 100 parts by mass of the total amount of all monomers constituting the (meta) alkyl acrylate copolymer (a1). In solution polymerization, in addition to the polymerization initiator, a chain transfer agent, an emulsifier, etc. may be added to the mixed solution of monomers. As the chain transfer agent, emulsifier, etc., known ones can be appropriately selected and used.

[0084] The amount of the polymerization initiator remaining in the mask adhesive layer is preferably small. Thereby, the amount of outgas generated during exposure can be reduced. As a method for reducing the amount of polymerization initiator remaining in the mask adhesive layer, there are a method of minimizing the addition amount of the polymerization initiator when polymerizing the (meth)acrylic acid alkyl ester copolymer (a1), a method of using a polymerization initiator that is easily thermally decomposed, a method of heating the adhesive at a high temperature for a long time in the adhesive coating and drying process to decompose the polymerization initiator in the drying process, and the like.

[0085] The 10-hour half-life temperature is used as an index representing the thermal decomposition rate of the polymerization initiator. The "half-life" indicates the time until half of the polymerization initiator decomposes. The "10-hour half-life temperature" indicates the temperature at which the half-life is 10 hours. It is preferable to use a polymerization initiator having a low 10-hour half-life temperature. The lower the 10-hour half-life temperature, the easier the polymerization initiator is thermally decomposed. As a result, it is less likely to remain in the mask adhesive layer. The 10-hour half-life temperature of the polymerization initiator is preferably 80°C or lower, more preferably 75°C or lower.

[0086] Examples of azo-based polymerization initiators having a low 10-hour half-life temperature include 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (10-hour half-life temperature: 30°C), 2,2'-azobisisobutyronitrile (10-hour half-life temperature: 65°C), 2,2-azobis (2,4-dimethylvaleronitrile) (10-hour half-life temperature: 51°C), dimethyl 2,2'-azobis(2-methylpropionate) (10-hour half-life temperature: 66°C), or 2,2'-azobis(2-methylbutyronitrile) (10-hour half-life temperature: 67°C), and the like. Examples of peroxide-based polymerization initiators having a low 10-hour half-life temperature include dibenzoyl peroxide (10-hour half-life temperature: 74°C), dilauroyl peroxide (10-hour half-life temperature: 62°C), and the like.

[0087] In the first embodiment, the raw material of the main agent containing the copolymer (a) contains a polymerization initiator, and the polymerization initiator ratio is preferably 400 to 2000. The polymerization initiator ratio indicates the ratio of the number of moles of all monomers used in the copolymer to the number of moles of the polymerization initiator. When the polymerization initiator ratio is 400 to 2000, a copolymer with a high molecular weight can be obtained. Therefore, in the pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. As a result, the distortion of the photomask substrate when the pellicle is attached to the photomask substrate can be suppressed. From the viewpoint of increasing the molecular weight, the polymerization initiator ratio is more preferably 700 or more, and even more preferably 1000 or more. From the viewpoints of compatibility with solvents and crosslinking agents and good coatability by a dispenser, the polymerization initiator ratio is more preferably 1800 or less, and even more preferably 1600 or less.

[0088] (3.3) Coating composition preparation step In the coating composition preparation step, a crosslinking agent (b) is added to the main agent to prepare a coating composition.

[0089] (3.3.1) Crosslinking agent (b) The crosslinking agent (b) contributes to the formation of a three-dimensional network structure by the reaction of the functional group of the crosslinking agent (b) with the (meth)acrylic acid alkyl ester copolymer (a1). The acrylic adhesive preferably contains a reaction product of the (meth)acrylic acid alkyl ester copolymer (a1) and the crosslinking agent (b). Thereby, the cohesive force of the obtained mask adhesive layer can be improved, paste residue can be suppressed, and the adhesive force at high temperature can be improved. The crosslinking agent (b) has at least one of an isocyanate group, an epoxy group, an acid anhydride, and a radical generating group.

[0090] Examples of the crosslinking agent (b) include monofunctional epoxy compounds, polyfunctional epoxy compounds, acid anhydride compounds, metal salts, metal alkoxides, aldehyde compounds, non-amino resin-based amino compounds, urea compounds, isocyanate compounds, metal chelate compounds, melamine compounds, aziridine compounds, azo radical generators, or organic peroxides, etc. Among them, in terms of excellent reactivity with the functional group components of the (meth)acrylic acid alkyl ester copolymer (a1), the crosslinking agent (b) is more preferably at least one of a monofunctional epoxy compound, a polyfunctional epoxy compound, an isocyanate compound, and an acid anhydride compound, and more preferably an acid anhydride compound.

[0091] Examples of the monofunctional epoxy compound include glycidyl (meth)acrylate, glycidyl acetate, butyl glycidyl ether, or phenyl glycidyl ether, etc. Examples of the polyfunctional epoxy compound include neopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, phthalic acid diglycidyl ester, dimer acid diglycidyl ester, triglycidyl isocyanurate, diglycerol triglycidyl ether, sorbitol tetraglycidyl ether, N, N, N', N'-tetraglycidyl m-xylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl diaminodiphenylmethane, etc. Examples of the acid anhydride compound include aliphatic dicarboxylic acid anhydrides, aromatic polyvalent carboxylic acid anhydrides, etc. Examples of the aliphatic dicarboxylic acid anhydride include maleic anhydride, hexahydrophthalic anhydride, hexahydro-4-methylphthalic anhydride, bicyclo[2.2.1]heptane-2,3-dicarboxylic acid anhydride, 2-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid anhydride, or tetrahydrophthalic anhydride, etc. Examples of the aromatic polyvalent carboxylic acid anhydride include phthalic anhydride and trimellitic anhydride. Examples of the isocyanate compound include xylylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, their multimers, derivatives, polymers, etc. These may be used alone or in combination of two or more.

[0092] The crosslinking agent (b) may be a product. Examples of the product of the crosslinking agent (b) include "Rikacid MH-700G" manufactured by Shin Nippon Rika Co., Ltd.

[0093] The addition amount of the crosslinking agent (b) is preferably 0.002 parts by mass to 3.000 parts by mass with respect to 100 parts by mass of the total amount of the monomers constituting the (meth)acrylic acid alkyl ester copolymer (a1). The addition amount of the crosslinking agent (b) is preferably 0.002 parts by mass to 3.000 parts by mass, more preferably 0.002 parts by mass to 2.000 parts by mass, still more preferably 0.005 parts by mass to 2.000 parts by mass, still more preferably 0.008 parts by mass to 1.000 parts by mass, and particularly preferably 0.01 parts by mass to 0.500 parts by mass with respect to 100 parts by mass of the total amount of the monomers constituting the (meth)acrylic acid alkyl ester copolymer (a1), from the viewpoints such as less occurrence of paste residue and relaxation of stress on the flatness of the photomask substrate to obtain a mask adhesive layer. If the content of the crosslinking agent (b) is 3.000 parts by mass or less, the crosslinking density of the (meth)acrylic acid alkyl ester copolymer (a1) does not become too large. Therefore, it is considered that the adhesive absorbs the stress applied to the photomask substrate, and the influence of the mask adhesive layer on the flatness of the photomask substrate is alleviated. The content of the crosslinking agent (b) is preferably 2.000 parts by mass or less, more preferably 1.000 parts by mass or less. On the other hand, if the content of the crosslinking agent (b) is 0.002 parts by mass or more, the crosslinking density does not become too small, so the handleability during the manufacturing process is maintained, and it is considered that paste residue is less likely to occur when peeling the pellicle from the photomask substrate.

[0094] (3.3.2) Addition method The method for adding the crosslinking agent (b) is not particularly limited and may be a known method.

[0095] (3.3.3) Coating composition In the first embodiment, the viscosity of the coating composition is 200 Pa·s or more. From the viewpoint that the coating can be performed without problems using a rotary positive displacement dispenser, the viscosity of the coating composition is preferably 1000 Pa·s or less, more preferably 800 Pa·s or less. From the viewpoint of making it easy to suppress the overhang of the mask adhesive layer from each side constituting the pellicle frame while thickening the mask adhesive layer, the viscosity of the coating composition is preferably 400 Pa·s or more, more preferably 500 Pa·s or more. From these viewpoints, the viscosity of the coating composition is preferably 200 Pa·s to 1000 Pa·s. The method for measuring the viscosity of the coating composition is the same as the method described in the examples.

[0096] Examples of the method for adjusting the viscosity of the coating composition to 200 Pa·s or more include increasing the molecular weight of the polymer (for example, (meth)acrylic acid alkyl ester copolymer, etc.) contained in the coating composition and / or increasing the polymer concentration. Examples of the method for adjusting the viscosity of the coating composition to 200 Pa·s or more include secondarily increasing the molecular weight of the polymer by crosslinking the polymer with a crosslinking agent.

[0097] The solid content concentration of the coating composition is not particularly limited, and is preferably 45% by mass to 95% by mass, more preferably 50% by mass to 75% by mass. "The solid content concentration of the coating composition" indicates the ratio of the mass of the solid content of the coating composition to the total amount of the coating composition. "The solid content of the coating composition" indicates the components obtained by removing the solvent from the coating composition.

[0098] The coating composition contains a main agent containing a (meth)acrylic acid alkyl ester copolymer (a) and a crosslinking agent (b).

[0099] (3.3.3.1) Dilution solvent The coating composition may further contain a diluting solvent. Thereby, the viscosity of the coating composition can be adjusted. As a result, when applying the coating composition to the other end face of the pellicle frame, the thickness and width of the coating composition are easily controllable. Examples of the diluting solvent include butyl acetate, propyl acetate, acetone, ethyl acetate, toluene, and the like. The content of the diluting solvent may be appropriately selected according to the viscosity of the coating composition.

[0100] (3.3.3.2) Catalyst The coating composition may further contain a catalyst. Examples of the catalyst include amine-based catalysts. Examples of the amine-based catalysts include octylate of (1,8-diazabicyclo-(5.4.0)undecene-7), triethylenediamine, and the like. The amine-based catalyst may be a product of San-Apro Ltd. such as "DBU", "DBN", "U-CAT", "U-CAT SA1", or "U-CAT SA102". The content of the catalyst is preferably 0.002 parts by mass to 3.000 parts by mass, more preferably 0.0050 parts by mass to 1.00 part by mass, based on 100 parts by mass of the (meth)acrylic acid alkyl ester copolymer (a1).

[0101] (3.3.3.3) Additive The coating composition may further contain an additive. Examples of the additive include a filler, a pigment, a diluent, an antioxidant, or a tackifier, and the like. These additives may be used alone or in combination of two or more.

[0102] (3.3.3.4) Surface modifier The coating composition preferably does not contain a surface modifier. Thereby, the amount of outgas generation can be suppressed.

[0103] (3.4) Coating step In the coating step, the coating composition is applied onto the adhesive layer forming surface of the pellicle frame.

[0104] The coating method of the coating composition is not particularly limited and may be a known method. Examples of the coating method of the coating composition include a method using a dispenser, a method using a syringe, brush painting, a hot melt method, or a molding method in which these coating methods are combined with a mold, etc.

[0105] The coating amount of the coating composition is appropriately adjusted according to the thickness of the mask adhesive layer of the obtained pellicle frame with a mask adhesive layer.

[0106] (3.5) Curing step In the curing step, the coating composition applied on the adhesive layer formation surface is cured to produce the mask adhesive layer. By curing the coating composition, a crosslinked structure of the (meth)acrylic acid alkyl ester copolymer (a1) and the crosslinking agent (b) in the coating composition is formed. Further, when the coating composition is cured, the solvent and / or residual monomer in the coating composition can be removed.

[0107] The curing method is not particularly limited, and examples include a method of heating the coating composition. The temperature for heating the coating composition is appropriately selected according to the boiling points of the solvent and residual monomer, the decomposition temperature of the (meth)acrylic acid alkyl ester copolymer (a1), etc., and is preferably 50°C to 200°C, more preferably 60°C to 190°C.

[0108] (4) Manufacturing method of the pellicle frame with a mask adhesive layer of the second embodiment The manufacturing method of the pellicle frame with a mask adhesive layer according to the second embodiment of the present disclosure is a manufacturing method for manufacturing the pellicle frame with a mask adhesive layer of the present disclosure. The manufacturing method includes preparing the pellicle frame (hereinafter, also referred to as the "pellicle frame preparation step"), polymerizing raw materials to produce a main agent containing a copolymer (a) (hereinafter, also referred to as the "main agent production step"), adding a crosslinking agent (b) to the main agent to produce a coating composition (hereinafter, the "coating composition production step"), applying the coating composition onto the adhesive layer forming surface of the pellicle frame (hereinafter, the "coating step"), and curing the coating composition applied onto the adhesive layer forming surface to produce the mask adhesive layer (hereinafter, the "curing step"). The weight average molecular weight of the copolymer (a) contained in the main agent is 300,000 or more. The main agent production step, the coating composition production step, the coating step, and the curing step are carried out in this order. The pellicle frame preparation step is carried out before the coating step.

[0109] Since the manufacturing method of the pellicle frame with a mask adhesive layer according to the second embodiment has the above configuration, it is possible to manufacture a pellicle frame with a mask adhesive layer in which the width of the adhesive layer forming surface of the pellicle frame is narrow and the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed even when the mask adhesive layer is thick. According to the manufacturing method of the pellicle frame with a mask adhesive layer according to the second embodiment, in the obtained pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. When the thickness of the mask adhesive layer increases, when a certain load is applied by attaching the photomask, the mask adhesive layer is likely to be distorted, and the stress applied to the photomask is reduced under the influence. As a result, the pellicle using the pellicle frame with a mask adhesive layer according to the second embodiment can suppress the distortion of the photomask substrate when attached to the photomask substrate.

[0110] The manufacturing method of the pellicle frame with a mask adhesive layer according to the second embodiment is the same as the manufacturing method of the pellicle frame with a mask adhesive layer according to the first embodiment, except that the weight average molecular weight of the copolymer (a) contained in the main agent is 500,000 or more, and the viscosity of the coating composition does not have to be 200 Pa·s or more. The description of the manufacturing method of the pellicle frame with a mask adhesive layer according to the second embodiment can incorporate the description of the manufacturing method of the pellicle frame with a mask adhesive layer according to the first embodiment.

[0111] (4.1) Pellicle Frame Preparation Step The pellicle frame preparation step is the same as that exemplified as the pellicle frame preparation step in the first embodiment.

[0112] (4.2) Main Agent Preparation Step The main agent preparation step is the same as that exemplified as the main agent preparation step in the first embodiment, except that the weight average molecular weight of the copolymer (a) contained in the main agent is 300,000 or more.

[0113] In the second embodiment, the weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is 300,000 or more. The weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is preferably 500,000 to 2,000,000, more preferably 600,000 to 1,500,000, and even more preferably 700,000 to 1,200,000. If the weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is 2,000,000 or less, it is easy to adjust the viscosity of the coating composition to an appropriate viscosity. As a result, it is easy to coat the coating composition to a desired size. The weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) is more preferably 1,500,000 or less, and even more preferably 1,200,000 or less.

[0114] (4.3) Coating Composition Preparation Step The coating composition preparation step is the same as that exemplified as the coating composition preparation step in the first embodiment, except that the viscosity of the coating composition does not have to be 200 Pa·s or more.

[0115] In the second embodiment, the viscosity of the coating composition is preferably 200 Pa·s or more. From the viewpoint that the coating can be performed without problems using a rotary positive displacement dispenser, the viscosity of the coating composition is more preferably 1000 Pa·s or less, and even more preferably 800 Pa·s or less. From the viewpoint of facilitating the suppression of the protrusion of the mask adhesive layer from each side constituting the pellicle frame while thickening the mask adhesive layer, the viscosity of the coating composition is more preferably 400 Pa·s or more, and even more preferably 500 Pa·s or more. From these viewpoints, the viscosity of the coating composition is preferably 200 Pa·s to 1000 Pa·s.

[0116] (4.4) Coating step The coating step is the same as that exemplified as the coating step in the first embodiment.

[0117] (4.5) Curing step The curing step is the same as that exemplified as the curing step in the first embodiment.

[0118] (5) Manufacturing method of a pellicle frame with a mask adhesive layer according to the third embodiment The manufacturing method of the pellicle frame with a mask adhesive layer according to the third embodiment of the present disclosure is a manufacturing method for manufacturing the pellicle frame with a mask adhesive layer of the present disclosure. The manufacturing method includes preparing the pellicle frame (hereinafter also referred to as "pellicle frame preparation step"), polymerizing a raw material containing a polymerization initiator to produce a main agent containing a copolymer (a) (hereinafter referred to as "main agent production step"), adding a crosslinking agent (b) to the main agent to produce a coating composition (hereinafter referred to as "coating composition production step"), applying the coating composition onto the adhesive layer formation surface of the pellicle frame (hereinafter referred to as "coating step"), and curing the coating composition applied onto the adhesive layer formation surface to produce the mask adhesive layer (hereinafter referred to as "curing step"). The polymerization initiator ratio is 400 to 2000. The polymerization initiator ratio indicates the ratio of the number of moles of all monomers used for the copolymer (a) to the number of moles of the polymerization initiator. The main agent production step, the coating composition production step, the coating step, and the curing step are carried out in this order. The pellicle frame preparation step is carried out before the coating step.

[0119] Since the manufacturing method of the pellicle frame with a mask adhesive layer according to the third embodiment has the above configuration, even if the width of the adhesive layer formation surface of the pellicle frame is narrow and the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the pellicle frame can be suppressed, and a pellicle frame with a mask adhesive layer can be manufactured. According to the manufacturing method of the pellicle frame with a mask adhesive layer according to the third embodiment, in the obtained pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. In addition, the elastic modulus of the mask adhesive layer is reduced. As a result, the pellicle using the pellicle frame with a mask adhesive layer according to the third embodiment can suppress the distortion of the photomask substrate when attached to the photomask substrate.

[0120] The manufacturing method of the pellicle frame with a mask adhesive layer according to the third embodiment is the same as the manufacturing method of the pellicle frame with a mask adhesive layer according to the first embodiment, except that the raw material contains a polymerization initiator, the polymerization initiator ratio is 400 to 2000, and the viscosity of the coating composition does not have to be 200 Pa·s or more. The description of the manufacturing method of the pellicle frame with a mask adhesive layer according to the third embodiment can incorporate the description of the manufacturing method of the pellicle frame with a mask adhesive layer according to the first embodiment.

[0121] (5.1) Pellicle Frame Preparation Step The pellicle frame preparation step is the same as that exemplified as the pellicle frame preparation step of the first embodiment.

[0122] (5.2) Main Agent Preparation Step The main agent preparation step is the same as that exemplified as the main agent preparation step of the first embodiment, except that the raw material contains a polymerization initiator and the polymerization initiator ratio (a / b) is 400 to 2000.

[0123] In the third embodiment, the polymerization initiator ratio is 400 to 2000. By setting the polymerization initiator ratio to 400 to 2000, in the obtained pellicle frame with a mask adhesive layer, it is easy to form a mask adhesive layer having a thickness of 500 μm or more while suppressing the protrusion of the mask adhesive layer. As a result, the distortion of the photomask substrate when the pellicle is attached to the photomask substrate can be suppressed. From the viewpoint of high molecular weight, the polymerization initiator ratio is preferably 700 or more, more preferably 1000 or more. From the viewpoints of compatibility with solvents and crosslinking agents and good coatability by a dispenser, the polymerization initiator ratio is preferably 1800 or less, more preferably 1600 or less.

[0124] (5.3) Coating composition preparation step The coating composition preparation step is the same as that exemplified as the coating composition preparation step of the first embodiment, except that the viscosity of the coating composition does not have to be 200 Pa·s or more. In the third embodiment, the viscosity of the coating composition is preferably 200 Pa·s or more. From the viewpoint that coating can be performed without problems with a rotary volumetric dispenser, the viscosity of the coating composition is more preferably 1000 Pa·s or less, still more preferably 800 Pa·s or less. From the viewpoint of making it easy to suppress the protrusion of the mask adhesive layer from each side constituting the pellicle frame while thickening the mask adhesive layer, the viscosity of the coating composition is more preferably 400 Pa·s or more, still more preferably 500 Pa·s or more. From these viewpoints, the viscosity of the coating composition is preferably 200 Pa·s to 1000 Pa·s.

[0125] (5.4) Coating step The coating step is the same as that exemplified as the coating step of the first embodiment.

[0126] (5.5) Curing step The curing step is the same as that exemplified as the curing step of the first embodiment.

[0127] (6) Method for manufacturing a pellicle The method for manufacturing a pellicle according to the present disclosure includes preparing a pellicle film (hereinafter, also referred to as "pellicle film preparation step"), manufacturing the pellicle frame with a mask adhesive layer according to the method for manufacturing a pellicle frame with a mask adhesive layer of the present disclosure (hereinafter, also referred to as "pellicle frame manufacturing step with a mask adhesive layer"), and stretching the pellicle film at the other end of the pellicle frame in the height direction of the pellicle frame (hereinafter, also referred to as "stretching step"). The pellicle frame manufacturing step with a mask adhesive layer and the stretching step may be performed in this order, or after the stretching step, a mask adhesive layer of the present disclosure may be provided on the pellicle frame on which the pellicle film is stretched to manufacture a pellicle.

[0128] Since the method for manufacturing a pellicle according to the present disclosure has the above configuration, even if the width of the adhesive layer formation surface of the pellicle frame is narrow and the mask adhesive layer is thick, it is possible to manufacture a pellicle in which the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed.

[0129] (6.1) Pellicle film preparation step In the pellicle film preparation step, the pellicle film is prepared.

[0130] The method for preparing the pellicle film is not particularly limited as long as it is a known method.

[0131] (6.2) Pellicle frame manufacturing step with a mask adhesive layer In the pellicle frame manufacturing step with a mask adhesive layer, the pellicle frame with a mask adhesive layer is manufactured according to the method for manufacturing a pellicle frame with a mask adhesive layer of the present disclosure.

[0132] The method for manufacturing a pellicle frame with a mask adhesive layer according to the present disclosure is the manufacturing method of any one of the pellicle frame manufacturing steps with a mask adhesive layer in the first to third embodiments.

[0133] (6.3) Stretching step In the stretching step, the pellicle film is stretched at the other end of the pellicle frame in the height direction of the pellicle frame.

[0134] The method of stretching the pellicle film is not particularly limited and may be any known method. Examples of the method of stretching the pellicle film include a method of applying a known adhesive to the other end of the pellicle frame to form a film adhesive layer and disposing the pellicle film on the film adhesive layer.

Examples

[0135] Hereinafter, the present disclosure will be described in more detail with reference to examples and the like, but the invention of the present disclosure is not limited to these examples only.

[0136] [1] Preparation Each component used in the examples and comparative examples is as follows.

[0137] [1.1] (Meth)acrylic acid alkyl ester monomer ·EA: Ethyl acrylate ·MMA: Methyl methacrylate ·BA: Butyl acrylate

[0138] [1.2] Functional group-containing monomer ·4-HBA: 4-Hydroxybutyl acrylate ·HEMA: 2-Hydroxyethyl methacrylate ·GMA: Glycidyl methacrylate

[0139] [1.3] Polymerization initiator ·AIBN: 2,2’-Azobisisobutyronitrile (10-hour half-life temperature: 65°C)

[0140] [1.4] Polymerization solvent ·Propyl acetate

[0141] [1.5] Crosslinking agent (b) · "Rikacid MH-700G" manufactured by Shin Nippon Rika Co., Ltd.

[0142] [1.6] Catalyst · Amine catalyst: "U-CAT SA-102" manufactured by San-Apro Limited (chemical formula: octylate of (1,8-diazabicyclo-(5.4.0)undecene-7))

[0143] [2] Examples 1 to 5 and Comparative Example 1 [2.1] Example 1 [2.1.1] Pericle frame preparation step As the pericle frame 11 shown in FIG. 1, an anodized aluminum pericle frame was prepared. The length L11 of the long side 111 of the pericle frame 11 (see FIG. 1) was 149 mm. The length L12 of the short side 112 of the pericle frame 11 (see FIG. 1) was 115 mm. The height L13 of the pericle frame 11 (see FIG. 2) was 2.5 mm. The frame width L14 of the pericle frame 11 was 2.0 mm. The width L1 of the adhesive layer forming surface S11A1 of the pericle frame 11 was 1.60 mm.

[0144] [2.1.2] Main agent preparation step The (meth)acrylic acid alkyl ester copolymer was prepared by a well-known method. Specifically, a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen inlet tube was prepared. 367 parts by mass of a polymerization solvent was placed in the reaction vessel, and a mixture of EA / 4-HBA / HEMA / GMA / AIBN (polymerization initiator) (300.4 parts by mass) was charged at a mass ratio of 270.0 / 9.0 / 15.0 / 6.0 / 0.40. In a nitrogen atmosphere, this reaction solution was reacted at 75°C for 6 hours and then at 95°C for 2 hours to obtain an acrylic copolymer solution (main agent) with a non-volatile content (copolymer) concentration of 50% by mass (weight average molecular weight: 700,000). Thereafter, the polymerization solvent was distilled off under reduced pressure to adjust the acrylic copolymer solution to a non-volatile content (copolymer) concentration of 56.0% by mass, which contained the (meth)acrylic acid alkyl ester copolymer (a1).

[0145] [2.1.3] Coating composition preparation step To the obtained acrylic copolymer solution (containing 100 parts by mass of the (meth)acrylic acid alkyl ester copolymer (a1)), a crosslinking agent (“MH-700G”) (0.0100 parts by mass) and a catalyst (“U-CAT SA-102”) (0.0040 parts by mass) were added, and they were stirred and mixed to obtain a coating composition.

[0146] [2.1.4] Coating step The prepared coating composition was applied onto the adhesive layer forming surface S11A1 of the pellicle frame 11 using a dispenser.

[0147] [2.1.5] Curing step The coating on the adhesive layer forming surface S11A1 of the pellicle frame 11 was dried at 80 °C for 120 minutes to obtain a dried coating. A protective film was placed on the dried coating and dried at 120 °C for 20 hours. Thereby, a mask adhesive layer 12 made of an adhesive composition was formed from the coating of the coating composition. That is, a pellicle frame 1 with a mask adhesive layer was obtained. The mask adhesive layer 12 was flattened by the protective film. The thickness L2 of the mask adhesive layer 12 (see Figure 2) was 509 mm.

[0148] [2.1.6] Pellicle film preparation step A pellicle film was prepared.

[0149] [2.1.7] Tensioning step A pellicle film was attached onto the other end surface S11B of the pellicle frame 11 of the pellicle frame 1 with a mask adhesive layer via a film adhesive layer. Thereby, a pellicle was obtained.

[0150] [2.2] Examples 2 to 5 Except that the mass of the polymerization solvent, the mass ratio of the mixture, and the mass of the mixture were changed to the values shown in Table 1 in the main agent preparation step, and the crosslinking agent content and the catalyst content were changed to the values shown in Table 2 in the coating composition preparation step, a pellicle was obtained in the same manner as in Example 1.

[0151]

Table 1

[0152] [2.3] Comparative Example 1 A pellicle was obtained in the same manner as in Example 1, except that an acrylic copolymer solution (main agent) was obtained by the method described below in the main agent production process, and the crosslinking agent content and the catalyst content were changed to the values shown in Table 2 in the coating composition production process.

[0153] (Meth)acrylic acid alkyl ester copolymer was prepared by a well-known method. Specifically, a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen inlet tube was prepared. 180 parts by mass of a polymerization solvent was placed in the reaction vessel, and a mixture of EA / 4-HBA / HEMA / GMA / AIBN (polymerization initiator) (423.4 parts by mass) was charged at a mass ratio of 378.0 / 12.6 / 21 / 8.4 / 3.4. In a nitrogen atmosphere, this reaction solution was reacted at 85°C for 6 hours and further at 95°C for 2 hours to obtain an acrylic copolymer solution (main agent) with a non-volatile content (copolymer) concentration of 70% by mass (weight average molecular weight: 138,000). Thereafter, the polymerization solvent was added to adjust the acrylic copolymer solution to a non-volatile content (copolymer) concentration of 64.5% by mass, which contained (meth)acrylic acid alkyl ester copolymer (a1).

[0154] [3] Measurement Method [3.1] Weight Average Molecular Weight (Mw) The weight average molecular weight (Mw) of the (meth)acrylic acid alkyl ester copolymer (a1) obtained by carrying out the main agent production process was measured using GPC under the following measurement conditions. The measurement results are shown in Table 2.

[0155] [3.1.1] GPC Measurement Conditions · Pump: Dual pump "KP-22-135" manufactured by From · Detector: Differential refractometer "RI-101" manufactured by Showa Denko KK · Column: Two "PLgel MIXED-B" (7.5×300 mm) columns manufactured by Agilent Technologies · Column temperature: 40°C · Mobile phase: Tetrahydrofuran for HPLC · Flow rate: 1.0 mL / min · Sample concentration: 0.1% (w / v) · Sample injection volume: 100 μL · Standard substance: Monodisperse polystyrene

[0156] [3.2] Viscosity of the coating composition The viscosity of the coating composition obtained by carrying out the coating composition preparation step was measured using an E-type viscometer (“TV-100EH” manufactured by Toki Sangyo Co., Ltd.). For the measurement, a cone rotor of 3°×R14 was used. The temperature was 25°C. The rotation speed of the cone rotor was 0.5 rpm or 1.0 rpm. The measurement results are shown in Table 2.

[0157] [3.3] Resin mass of the mask adhesive layer The mass of only the pellicle frame was measured in advance before carrying out the coating step. After carrying out the coating step and the curing step for the coating composition, the mass of the pellicle with the mask adhesive layer was measured. The difference between the two was taken as the “resin mass of the mask adhesive layer”.

[0158] [3.4] Adhesive width, thickness and mask contact width of the mask adhesive layer The pellicle frame 1 with the mask adhesive layer obtained by carrying out the curing step was observed using a digital microscope (“VHX6000” manufactured by Keyence Corporation). The observation magnification was 20 times. Using the attached measurement tool, the adhesive width L3 of the mask adhesive layer 12, the thickness L2 of the mask adhesive layer 12, and the mask contact width L4 of the mask adhesive layer 12 were each measured. The measurement results are shown in Table 2.

[0159] [3.5] Area of the protruding portion The obtained pellicle frame 1 with a mask adhesive layer after the curing process was observed using a digital microscope ("VHX6000" manufactured by Keyence Corporation). The observation magnification was 50 times. Specifically, the entire circumference of the pellicle frame 1 with the mask adhesive layer was observed from the side where the mask adhesive layer 12 was not formed in the height direction of the pellicle frame 11 (from the positive Z-axis direction). The area of the protruding portion R12 of the mask adhesive layer 12 was calculated using the attached measurement tool. The pellicle was illuminated with light through the pellicle frame with a protective film, and the portion recognized as the mask adhesive layer 12 was defined as the protruding portion R12 of the mask adhesive layer 12.

[0160] [4] Evaluation of the protruding portion of the mask adhesive layer The protruding portion of the mask adhesive layer was evaluated according to the following evaluation criteria based on the measurement results of the area of the protruding portion. The evaluation results are shown in Table 2. The evaluation of the acceptable protruding portion of the mask adhesive layer is "A".

[0161] [3.1] Evaluation criteria "A": The area of the protruding portion was 0.10 mm 2 or less. "B": The area of the protruding portion was less than 0.10 mm 2

[0162]

Table 2

[0163] In Table 2, "crosslinking agent content" indicates the mass ratio of the crosslinking agent to the total amount of the copolymer (a). "Catalyst content" indicates the mass ratio of the catalyst to the total amount of the copolymer (a).

[0164] The pellicle frame 1 with a mask adhesive layer of Comparative Example 1 included a pellicle frame 11 and a mask adhesive layer 12. The width L1 of the adhesive layer formation surface S11A1 was less than 2.0 mm. The thickness L2 of the mask adhesive layer 12 was not more than 500 μm. The area of the protruding portion R12 of the mask adhesive layer 12 was 0.10 mm 2 ​It was not the case below. Therefore, the evaluation result of the protruding part of Comparative Example 1 was "B". As a result, it was found that the pellicle frame 1 with a mask adhesive layer of Comparative Example 1 was not a "pellicle frame with a mask adhesive layer in which, even if the width of the adhesive layer formation surface of the pellicle frame is narrow and the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed".

[0165] The pellicle frames 1 with mask adhesive layers of Examples 1 to 5 included a pellicle frame 11 and a mask adhesive layer 12. The width L1 of the adhesive layer formation surface S11A1 was less than 2.0 mm. The thickness L2 of the mask adhesive layer 12 was 500 μm or more. The area of the protruding part R12 of the mask adhesive layer 12 was 0.10 mm 2 It was the case below. Therefore, the evaluation results of the protruding parts of Examples 1 to 5 were "A". From these results, it was found that the pellicle frames 1 with mask adhesive layers of Examples 1 to 5 were "pellicle frames with a mask adhesive layer in which, even if the width of the adhesive layer formation surface of the pellicle frame is narrow and the mask adhesive layer is thick, the protrusion of the mask adhesive layer from each side constituting the pellicle frame is suppressed".

Explanation of Signs

[0166] 1 Pellicle frame with mask adhesive layer 11 Pellicle frame 111 Long side 112 Short side 12 Mask adhesive layer S11A1 Adhesive layer formation surface R12 Protruding part

Claims

1. A pellicle frame with a mask adhesive layer, comprising a pellicle frame and a mask adhesive layer for attaching the pellicle frame to a photomask substrate, wherein the pellicle frame has an adhesive layer formation surface on one end in the height direction of the pellicle frame, on which the mask adhesive layer is formed, the width of each side constituting the pellicle frame is 4.6 mm or less, the thickness of the mask adhesive layer in the height direction of the pellicle frame is 500 μm or more, The area of the protruding part of the mask adhesive layer is 0.10 mm ２ or less, and the overhanging part refers to the part that protrudes from each side constituting the pellicle frame of the mask adhesive layer when observing the pellicle frame with the mask adhesive layer at a magnification of 50 times from the side where the mask adhesive layer is not formed in the height direction of the pellicle frame, and it is a pellicle frame with a mask adhesive layer indicating the part that protrudes from each side of the pellicle frame of the mask adhesive layer on the entire circumference of the pellicle frame.

2. The adhesive layer formation surface is a plane orthogonal to the height direction of the pellicle frame, and the width of the adhesive layer formation surface is 2.0 mm or less. The pellicle frame with a mask adhesive layer according to claim 1.

3. The thickness ratio of the mask adhesive layer is 5% to 30%, and the thickness ratio indicates the ratio of the thickness of the mask adhesive layer to the total value of the thickness of the mask adhesive layer and the height of the pellicle frame. The pellicle with a mask adhesive layer according to claim 1.

4. A pellicle, comprising the pellicle frame with a mask adhesive layer according to claim 1, and a pellicle film stretched at the other end in the height direction of the pellicle frame.

5. A manufacturing method for manufacturing the pellicle frame with a mask adhesive layer according to claim 1, comprising: preparing the pellicle frame; polymerizing raw materials to produce a main agent containing a copolymer (a); adding a crosslinking agent (b) to the main agent to produce a coating composition; coating the coating composition on the adhesive layer formation surface of the pellicle frame; curing the coating composition coated on the adhesive layer formation surface to produce the mask adhesive layer, and the viscosity of the coating composition is 200 Pa·s or more. A manufacturing method for a pellicle frame with a mask adhesive layer.

6. A manufacturing method for manufacturing the pellicle frame with a mask adhesive layer according to claim 1, comprising: preparing the pellicle frame; polymerizing raw materials to produce a main agent containing a copolymer (a); adding a crosslinking agent (b) to the main agent to produce a coating composition; coating the coating composition on the adhesive layer formation surface of the pellicle frame; Curing the coating composition applied on the adhesive layer forming surface to produce the mask adhesive layer; having; A method for manufacturing a pellicle frame with a mask adhesive layer, wherein the weight average molecular weight of the copolymer (a) contained in the main agent is 300,000 or more.

7. A manufacturing method for manufacturing a pellicle frame with a mask adhesive layer according to Claim 1, comprising: preparing the pellicle frame; polymerizing a raw material containing a polymerization initiator to produce a main agent containing a copolymer (a); adding a crosslinking agent (b) to the main agent to produce a coating composition; applying the coating composition on the adhesive layer forming surface of the pellicle frame; curing the coating composition applied on the adhesive layer forming surface to produce the mask adhesive layer; having; the polymerization initiator ratio is 400 to 2000; A method for manufacturing a pellicle frame with a mask adhesive layer, wherein the polymerization initiator ratio represents the ratio of the number of moles of all monomers used for the copolymer (a) to the number of moles of the polymerization initiator.

8. preparing a pellicle film; producing the pellicle frame with a mask adhesive layer by the manufacturing method of the pellicle frame with a mask adhesive layer according to any one of Claims 5 to 7; stretching the pellicle film at the other end in the height direction of the pellicle frame of the pellicle frame; A method for manufacturing a pellicle, comprising.

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