Pellicle frame, pellicle, exposure master, exposure apparatus, and method for manufacturing a pellicle

Abstract

The purpose of the present invention is to provide: a pellicle frame in which warpage caused by tension in a pellicle film is suppressed, and which can suppress warpage of an original plate cause by deformation of the pellicle frame; a pellicle; and a pellicle production method.　A pellicle frame comprises: a hard frame member (12A) for supporting a pellicle film; and a soft frame member (11X) for connection to an original plate having a pattern. The soft frame member (11X) is connected to the hard frame member (12A). The soft frame member (11X) is obtained by alternately laminating base material layers (112) and adhesive layers (111) in the thickness direction orthogonal to the planar direction of the pellicle film, such that an adhesive layer (111) is disposed at each end. The Young's modulus of the hard frame member (12A) is higher than the apparent Young's modulus of the soft frame member (11X). The Young's modulus of the hard frame member (12A) is not less than 25 GPa.

Description

[Technical Field]

[0001] The present disclosure relates to a pellicle frame, a pellicle, an exposure master, an exposure apparatus, and a method for manufacturing a pellicle. [Background technology]

[0002] As the performance of semiconductor exposure processes improves, the pattern width of semiconductor integrated circuits is becoming increasingly finer. However, in the exposure process, if foreign matter such as dust adheres to the master, exposure defects may occur, potentially resulting in a drop in the yield of semiconductor integrated circuits. A pellicle, which is a master cover, is attached to the master to prevent foreign matter such as dust from adhering to the surface of the master. The pellicle includes a support frame, a pellicle film supported on one end surface of the support frame, and an adhesive layer provided on the other end surface of the support frame (hereinafter referred to as the "master-side end surface") (see, for example, Patent Document 1). Hereinafter, the support frame and the adhesive layer provided on the other end surface of the support frame may be collectively referred to as the "pellicle frame."

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-081454 Summary of the Invention [Problem to be solved by the invention]

[0004] When a pellicle film is stretched over a pellicle frame, the tension of the pellicle film can cause a force to act inward on the pellicle frame. If the support frame is soft, the tension of the pellicle film can cause the support frame to distort inward. When the support frame distorts inward, the available exposure area decreases accordingly. Therefore, there is a demand for a pellicle frame that can minimize the amount of inward distortion of the support frame.

[0005] On the other hand, in recent years, exposure wavelengths have become shorter, leading to increasingly finer pattern widths. If the support frame is too hard, deformation of the support frame may cause distortion of the master when the pellicle is attached to the master with the adhesive layer. This may result in misalignment of the circuit pattern on the master. Specifically, the support frame, when in a stand-alone state, may be distorted in the thickness direction perpendicular to the surface direction of the pellicle film. When attaching the pellicle to the master, the support frame is pressed against the flat portion of the master. As a result, the support frame is attached to the master in a state where it has been straightened flat. When the support frame has been straightened flat, it has a restoring force that causes it to return to its original distorted shape. When the amount of distortion in the direction perpendicular to the surface direction of the pellicle film is constant, the restoring force increases as the support frame becomes stiffer (i.e., the higher the bending rigidity of the support frame). If the restoring force is large, there is a risk that the master will be distorted due to deformation of the support frame. Therefore, there is a demand for a pellicle frame with reduced bending rigidity.

[0006] The present disclosure has been made in consideration of the above circumstances. The problem that one embodiment of the present disclosure aims to solve is to provide a pellicle frame, a pellicle, and a method for manufacturing a pellicle that can suppress distortion caused by tension in the pellicle film and suppress distortion of the original plate caused by deformation of the pellicle frame. [Means for solving the problem]

[0007] The means for solving the above problems include the following embodiments. <1> a rigid frame member for supporting the pellicle membrane; a soft frame member connected to the hard frame member for connecting to a master having a pattern; Equipped with the soft frame member is formed by alternately laminating base material layers and adhesive layers in a thickness direction perpendicular to a surface direction of the pellicle film, with the adhesive layers being disposed on both ends; the Young's modulus of the hard frame member is higher than the apparent Young's modulus of the soft frame member; A pellicle frame, wherein the hard frame member has a Young's modulus of 25 GPa or more. <2> The rigid frame member is made of a single material. <1> The pellicle frame according to claim 1. <3> The Young's modulus of the rigid frame member is 90 Gpa or more. <1> or <2> The pellicle frame according to claim 1. <4> The ratio of the height of the rigid frame member to the height of the pellicle frame is 15% to 65%. <1> ~ <3> 10. A pellicle frame according to any one of the preceding items. <5> the total number of layers of the base material layer and the adhesive layer is 5 or more; <1> ~ <4> 10. A pellicle frame according to any one of the preceding items. <6> The thickness of each of the adhesive layers is 0.01 mm or more and 0.5 mm or less. <1> ~ <5> 10. A pellicle frame according to any one of the preceding items. <7> the total thickness of the adhesive layers included in the soft frame member is 0.2 times or more and 4 times or less the total thickness of the base material layers included in the soft frame member; <1> ~ <6> 10. A pellicle frame according to any one of the preceding items. <8> The Young's modulus of the base material layer is 10,000 times or more and 9,000,000 times or less than the Young's modulus of the adhesive layer. <1> ~ <7> 10. A pellicle frame according to any one of the preceding items. <9> The thickness of each of the base layers is 2.5 mm or less. <1> ~ <8> 10. A pellicle frame according to any one of the preceding items. <10> The surface of the adhesive layer satisfies any one of the following (A) to (C): <1> ~ <9> 10. A pellicle frame according to any one of the preceding items. (A) an inorganic layer is formed on at least the inner wall surface of the adhesive layer; (B) At least the inner wall surface of the adhesive layer satisfies the following formula (1): (C) At least the inner wall surface of the adhesive layer satisfies the following formula (2): Equation (1):([CNO - 2s ] / [CNO - 50s ])≧2.00 (In the formula (1), [CNO - 2s ] is a time-of-flight secondary ion mass spectrometry (TSMS) method for measuring a first depth from the surface of the adhesive layer, using an ion source of Bi3 ++ CNO analyzed using a primary ion gun with an irradiation area of ​​100 μm × 100 μm. - indicates the normalized intensity of the first depth is formed by irradiating a 600 μm square area of ​​the surface with a sputter ion gun, which is an argon gas cluster ion beam having a beam voltage of 20 kV and a beam current of 20 nA, for a cumulative period of 2 seconds; [CNO - 50s ] is a CNO obtained by analyzing the second deep portion having the second depth by time-of-flight secondary ion mass spectrometry. - indicates the normalized intensity of The second depth is formed by irradiating the area with the sputter ion gun for a cumulative period of 50 seconds. Formula (2):([C3 - 2s ] / [C3 - 50s ])≧1.10 (In the formula (2), [C3 - 2s ] is C3 obtained by analyzing the first deep portion by time-of-flight secondary ion mass spectrometry. - indicates the normalized intensity of [C3 - 50s ] is C3 obtained by analyzing the second deep part by time-of-flight secondary ion mass spectrometry. - ) <11> The flexible frame member includes an air passage passing through the flexible frame member, or the air passage and an air filter disposed in the air passage. <1> ~ <10> 10. A pellicle frame according to any one of the preceding items. <12> The aforementioned <1> ~ <11> a pellicle frame according to any one of the above items; a pellicle membrane supported by the rigid frame member; A pellicle comprising: <13> a master having a pattern; The master is attached to a surface having a pattern thereon. <12> The pellicle described in Including, exposed master plate. <14> a light source that emits exposure light; The aforementioned <13> an exposure master according to the above item (1); an optical system that guides the exposure light emitted from the light source to the exposure master; and an exposure apparatus, wherein the exposure master is positioned so that exposure light emitted from the light source is transmitted through the pellicle film and irradiated onto the master; <15> The aforementioned <12> A method for manufacturing a pellicle according to the present invention, providing the rigid frame member; a lamination step of alternately laminating at least one base layer sheet and a plurality of adhesive layer layers in the thickness direction to form a laminate; a punching step of punching the laminate to form an exposure through-hole along the thickness direction, thereby forming the soft frame member; a connecting step of connecting the rigid frame member to the flexible frame member; A method for manufacturing a pellicle, comprising: <16> The method includes at least one of the steps of: coating an inorganic layer on at least the inner wall surface of the adhesive layer; subjecting at least the inner wall surface of the adhesive layer to plasma nitriding treatment; and subjecting at least the inner wall surface of the adhesive layer to extreme ultraviolet irradiation treatment. <15> A method for manufacturing a pellicle according to claim 1. <17> the flexible frame member includes an air passage passing through the flexible frame member; the layer for adhesive layer is a sheet for adhesive layer, an air passage processing step of processing at least one base layer raw sheet and a plurality of adhesive layer raw sheets so that the air passage is formed, to form the at least one base layer sheet and the plurality of adhesive layer sheets; The air passage processing step is performed before the lamination step. <15> or <16> A method for manufacturing a pellicle according to claim 1. <18> the flexible frame member includes the air passage and an air filter disposed in the air passage; a filter fixing step of arranging the ventilation filter in a part of the at least one base layer sheet or the plurality of adhesive layer sheets so that the ventilation filter is disposed in the ventilation path, The filter fixing step is performed after the air passage processing step and before the lamination step. <17> A method for manufacturing a pellicle according to claim 1. [Effects of the Invention]

[0008] According to the present disclosure, there is provided a pellicle frame, pellicle, exposure master, exposure apparatus, and method for manufacturing a pellicle that can suppress distortion caused by tension in the pellicle film and suppress distortion of the master caused by deformation of the pellicle frame. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a three-layer laminate for illustrating a method for calculating the apparent Young's modulus (E) of a horizontally laminated laminate. [Figure 2] FIG. 2 is a cross-sectional view of a three-layer laminate for explaining a method for calculating the apparent Young's modulus (E) of a horizontally laminated laminate. [Figure 3] FIG. 3 is a cross-sectional view of a calculation model having the same layered structure as the pellicle frame according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a cross-sectional view of a pellicle according to a second embodiment of the present disclosure. [Figure 5] FIG. 5 is a cross-sectional view of a pellicle according to a third embodiment of the present disclosure. [Figure 6] FIG. 6 is a cross-sectional view of a pellicle according to a fourth embodiment of the present disclosure. [Figure 7] FIG. 7 is a cross-sectional view of a pellicle according to a fifth embodiment of the present disclosure. [Figure 8] FIG. 8 is a cross-sectional view of a pellicle according to Reference Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0010] In the present disclosure, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In the numerical ranges described in this disclosure, the upper or 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, when there are multiple substances corresponding to each component, the amount of each component means the total amount of the multiple substances unless otherwise specified. In the present disclosure, the term "process" refers not only to an independent process, but also to a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved.

[0011] (1) Pellicle frame The pellicle frame of the present disclosure comprises a hard frame member for supporting a pellicle film and a soft frame member for being attached to a master plate having a pattern. The soft frame member is connected to the hard frame member. The soft frame member is formed by alternately laminating base layers and adhesive layers in a thickness direction perpendicular to the surface direction of the pellicle film, with the adhesive layers disposed on both ends. The Young's modulus of the hard frame member is higher than the apparent Young's modulus of the soft frame member. The Young's modulus of the hard frame member is 25 GPa or more.

[0012] In the present disclosure, "perpendicular" is not limited to intersecting at an angle of 90°, but also includes intersecting at an angle within the range of 90±5°. In this disclosure, the "Young's modulus of a rigid frame member" refers to the Young's modulus of the material of a rigid frame member having a single layer structure, or the Young's modulus of the material of a rigid frame member having a multilayer structure. If the rigid frame member has a multilayer structure, it is the Young's modulus when the multiple materials of the multilayer structure rigid frame member are considered as one material, and indicates a value calculated based on the calculation method for the apparent Young's modulus (E) of a horizontally stacked laminate. In the present disclosure, the "apparent Young's modulus of the flexible frame member" refers to the Young's modulus when the multiple materials of the multi-layered flexible frame member are considered as one material, and indicates a value calculated based on a calculation method for the apparent Young's modulus (E) of a horizontally stacked laminate. Details of the calculation method for the apparent Young's modulus will be described later.

[0013] The pellicle frame of the present disclosure has the above-described configuration, thereby suppressing distortion caused by the tension of the pellicle film and suppressing distortion of the master plate caused by deformation of the pellicle frame. This is presumably due mainly to the following reasons. When a pellicle film is stretched over a pellicle frame, a force may act toward the inside of the pellicle frame due to the tension of the pellicle film. In the pellicle frame of the present disclosure, the pellicle film is supported by a hard frame member that is harder than the soft frame member. Furthermore, the Young's modulus of the hard frame member is 25 GPa or greater. Therefore, the pellicle frame of the present disclosure is less likely to be distorted toward the inside of the pellicle frame due to the tension of the pellicle film. As a result, the pellicle frame of the present disclosure suppresses distortion caused by the tension of the pellicle film. Therefore, it is presumed that the pellicle frame of the present disclosure can prevent a reduction in the exposure area. When the pellicle of the present disclosure (hereinafter sometimes simply referred to as "pellicle") is attached to the master, the pellicle frame is pressed against the flat portion of the master. This allows the pellicle frame to be attached to the master in a flat, corrected state. When the pellicle frame is flat, it has a restoring force that tends to return it to its original, distorted shape. In the pellicle frame of the present disclosure, a soft frame member that is softer than the hard frame member is directly attached to the flat surface of the master. Therefore, the restoring force is less than when the soft frame member has the same hardness as the hard frame member. As a result, it is believed that the pellicle frame of the present disclosure can reduce the restoring force caused by attachment to the master. Therefore, the pellicle frame of the present disclosure can suppress distortion of the master caused by deformation of the pellicle frame attached to the master.

[0014] The pellicle frame is a rectangular cylindrical object. The pellicle frame has an exposure through-hole. The exposure through-hole is a hollow portion of the pellicle frame, and represents a space through which light transmitted through the pellicle film passes to reach the original. The shape of the pellicle frame when viewed from the thickness direction is rectangular. The rectangular shape may be a square or a rectangle. "Rectangle" refers to a right-angled quadrilateral. "Square" refers to a shape in which all four sides constituting a rectangle are the same length. "Rectangle" refers to any rectangular shape excluding squares.

[0015] The rectangular shape of the pellicle frame seen from the thickness direction is made up of four sides. The length of one side in the longitudinal direction (hereinafter referred to as "side length") is preferably 200 mm or less. The size of the pellicle frame is standardized depending on the type of exposure device. A side length of 200 mm or less of the pellicle frame satisfies the standardized size for exposure using extreme ultraviolet (EUV) light (wavelength: 3 nm to 30 nm) (hereinafter referred to as "EUV exposure"). The length of one side in the short direction (hereinafter referred to as "width of one side") can be, for example, 5 mm to 180 mm, preferably 80 mm to 170 mm, and more preferably 100 mm to 160 mm. The height of the pellicle frame (i.e., the length of the pellicle frame in the thickness direction) is preferably 2.5 mm or less, and more preferably 2.4 mm or less. This allows the pellicle frame to meet the size standardized for EUV exposure. The height of the pellicle frame standardized for EUV exposure is, for example, 2.375 mm. The mass of the pellicle frame is preferably 15 g or less, which makes the pellicle frame suitable for use in EUV exposure.

[0016] The pellicle frame of the present disclosure includes a hard frame member and a soft frame member, which are stacked in the thickness direction.

[0017] (1.1) Rigid frame members The rigid frame member is used to support the pellicle frame. The term "hard" in the context of a hard frame member indicates that it has hard properties in comparison with a soft frame member.

[0018] The material, shape, etc. of the rigid frame member are not particularly limited as long as they can support the pellicle film. The rigid frame member is preferably made of a single material. This allows the rigid frame member to be prepared with a high productivity by preparing a portion that will become the rigid frame member as a support substrate, forming a pellicle film on the support substrate, and then removing a portion of the support substrate by etching to prepare a support substrate to which the pellicle film is connected.

[0019] The Young's modulus of the rigid frame member is 25 Pa or more. This gives the rigid frame member sufficient hardness. Therefore, even if a pellicle film is stretched across the rigid frame member, the pellicle frame is less likely to be distorted by the tension of the pellicle film. It is more preferable that the Young's modulus of the rigid frame member is 50 GPa or more. When the Young's modulus of the rigid frame member is 50 GPa or more, even if a pellicle film is stretched over the rigid frame member, the pellicle frame is less likely to be distorted inward by the tension of the pellicle film. It is even more preferable that the Young's modulus of the rigid frame member is 90 GPa or more. When the Young's modulus of the rigid frame member is 90 GPa or more, even if a pellicle film is stretched over the rigid frame member, the pellicle frame is less likely to be distorted inward by the tension of the pellicle film. The Young's modulus of the hard frame member is more preferably 90 GPa to 300 GPa, and even more preferably 150 GPa to 300 GPa. Examples of materials having a Young's modulus of 25 GPa or more include glass, aluminum, titanium, titanium alloys, silicon, stainless steel, polyethylene, acrylic resin, vinyl chloride resin, and polystyrene resin. Examples of materials with a Young's modulus of 50 GPa or more include glass, aluminum, titanium, titanium alloys, silicon, and stainless steel. Examples of materials with a Young's modulus of 90 GPa or more include titanium, titanium alloys, silicon, and stainless steel. Examples of materials with a Young's modulus of 150 GPa or more include silicon and stainless steel. The Young's modulus of the rigid frame member is measured by a tensile test (JIS G0567J). However, if the rigid frame member is made of resin, the value is measured by a three-point bending test (JIS K7171). Whether or not the material of the hard frame member is resin is determined by whether or not the material of the hard frame member undergoes thermal decomposition at 550°C.

[0020] Examples of materials for the hard frame member include metal materials (e.g., aluminum, titanium, stainless steel, etc.), ceramic materials (e.g., silicon, glass, etc.), and resins (e.g., polyethylene resin, acrylic resin, polyvinyl chloride resin, polystyrene resin, etc.). In particular, the material of the rigid frame member preferably contains aluminum, titanium, stainless steel, silicon, or glass, from the viewpoint of not containing a large amount of water and being able to suppress the amount of outgassing, and more preferably contains aluminum, titanium, or silicon.

[0021] In order to reduce the water content and suppress the amount of outgassing, the surface of the rigid frame member may be subjected to a known surface treatment that makes the surface of the rigid frame member hydrophobic, or may be coated with a material with a low water content (e.g., an inorganic material, a ceramic material, etc.).

[0022] The height of the rigid frame member (i.e., the length of the rigid frame member in the thickness direction) is not particularly limited, and is preferably 0.3 mm to 1.5 mm, more preferably 0.5 mm to 1.0 mm, from the viewpoint of suppressing distortion of the master plate caused by deformation of the pellicle frame and suppressing distortion caused by the tension of the pellicle film.

[0023] The ratio of the height of the rigid frame member to the height of the pellicle frame (hereinafter referred to as the "height ratio of the rigid frame member") is not particularly limited, and from the viewpoint of suppressing distortion of the master plate due to deformation of the pellicle frame, it is preferably 65% ​​or less, more preferably 60% or less, even more preferably 50% or less, and particularly preferably 45% or less. From the viewpoint of suppressing distortion caused by the tension of the pellicle membrane, the height ratio of the hard frame member is preferably 15% or more, more preferably 20% or more, and even more preferably 25% or more. From these viewpoints, the height ratio of the rigid frame member is preferably 15% to 65%, more preferably 20% to 65%, even more preferably 25% to 65%, particularly preferably 25% to 50%, and even more preferably 28% to 45%.

[0024] (1.2) Soft frame members The flexible frame is used to attach the pellicle to a master having a pattern. The flexible frame is connected to a hard frame. The master will be described later. The term "soft" in the soft frame member indicates that it has soft properties in comparison with a hard frame member.

[0025] The soft frame member is formed by alternately laminating base layers and adhesive layers in a thickness direction perpendicular to the surface direction of the pellicle film, with the adhesive layers disposed on both ends.

[0026] The material and shape of the soft frame member are not particularly limited as long as they can support the pellicle membrane.

[0027] The apparent Young's modulus of the soft frame member is less than 25 GPa. This makes the soft frame member sufficiently soft. Therefore, even when the pellicle is attached to the master, the restoring force is further reduced. The apparent Young's modulus of the soft frame member is more preferably 1 GPa to 15 GPa, and even more preferably 3 GPa to 10 GPa.

[0028] (1.2.1) Calculation method of apparent Young's modulus of pellicle frame The apparent Young's modulus of the pellicle frame is calculated based on the calculation method for the apparent Young's modulus (E) of a horizontally stacked laminate. Specifically, first, a calculation model having the same laminate structure as the pellicle frame is introduced. Then, the apparent Young's modulus of the calculation model is calculated based on the calculation method for the apparent Young's modulus (E) of a horizontally stacked laminate. The calculated apparent Young's modulus of the calculation model is considered to be the apparent Young's modulus of the pellicle frame in the present disclosure. The calculated apparent Young's modulus of the flexible frame member of the calculation model is considered to be the apparent Young's modulus of the flexible frame member in the present disclosure. Hereinafter, a method for calculating the apparent Young's modulus (E) of a horizontally laminated laminate and a method for calculating the apparent Young's modulus of a calculation model will be described in this order.

[0029] (1.2.1.1) Calculation method for apparent Young's modulus of horizontally laminated laminate A method for calculating the apparent Young's modulus (E) of a horizontally stacked laminate will be described with reference to Figures 1 and 2. Figures 1 and 2 are cross-sectional views of a three-layer laminate for explaining the method for calculating the apparent Young's modulus (E) of a horizontally stacked laminate. In particular, Figure 2 shows the strain distribution of the laminate shown in Figure 1.

[0030] The bending stiffness (EI) of the laminate is the bending stiffness (E i I i ) can be calculated by taking the sum of The moment of inertia (I i ) is calculated by determining the neutral axis position (λ) of the laminate. From the basic assumptions of beam bending in Figures 1 and 2, equation (i) holds within the elastic limit.

[0031]

number

[0032] In equation (i), "ρ" is the radius of curvature due to the bending moment (see Figure 2), "λ" is the distance from the top edge of the laminate to the neutral axis (see Figure 1), "y" is the coordinate pointing downward from the top edge of the laminate (see Figure 1), and "ε y ” is the normal strain in y, “σy " denotes the normal stress at y, and "E" denotes the apparent Young's modulus of the laminate.

[0033] 1 and 2, the formula (ii) is established at any cross section, and therefore the following formula (iii) is established.

[0034]

number

[0035] In formula (ii), “E x " is the Young's modulus of each layer (the Xth layer counted from one end face of the laminate), "h x " represents the length between one end face of the laminate and the face of the Xth layer counting from the one end face of the laminate on the other end face side of the laminate (see FIG. 1), and "b" represents the width of the laminate (see FIG. 1). X represents an integer of 1 to 3.

[0036]

number

[0037] In formula (iii), "h" represents the length from one end face to the other end face of the laminate (see FIG. 1).

[0038] Generalizing equation (iii), when n layers of sawn boards are stacked, the neutral axis position (λ) is given by equation (iv) ) where n is a natural number.

[0039]

number

[0040] In formula (iv), t i (h i -h i-1 ), and h0(h i―1 where i=1) is 0.

[0041] The bending stiffness (EI) of the laminate is calculated by dividing the bending stiffness of each sawn board with respect to the determined neutral axis position, Ei I i The sum of these is expressed as the following formula (v).

[0042]

number

[0043] The apparent Young's modulus (E) of the laminate is calculated by converting equation (v) into the second moment of area (bh 3 / 12) This is calculated by dividing the

[0044]

number

[0045] The bending stiffness of the flexible frame member can be calculated from equation (v) using the parameters of the flexible frame member. Using the parameters of the soft frame member, the apparent Young's modulus of the soft frame member can be calculated from equation (vi). Using the parameters of the hard frame member and the soft frame member, the bending stiffness of the pellicle frame can be calculated from equation (v). The apparent Young's modulus of the pellicle frame can be calculated from equation (vi) using the parameters of the hard frame member and the soft frame member.

[0046] (1.2.2) Calculation method of apparent Young's modulus and bending rigidity of pellicle frame Specifically, a method for calculating the apparent Young's modulus and bending rigidity of the pellicle frame will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view of a calculation model having the same layered structure as the pellicle frame according to the first embodiment of the present disclosure.

[0047] The pellicle frame according to the first embodiment is a rectangular cylindrical object. The pellicle frame according to the first embodiment is an assembled product, and includes a soft frame member 11X and a hard frame member 12A. The soft frame member 11X and the hard frame member 12A are stacked in the thickness direction of the pellicle frame according to the first embodiment. The Young's modulus of the hard frame member 12A is higher than the apparent Young's modulus of the soft frame member 11X. The Young's modulus of the hard frame member 12A is 25 GPa or more.

[0048] The flexible frame member 11X is formed by alternately stacking (m+1) adhesive layers 111 and m base layers 112 in the thickness direction of the pellicle frame according to the first embodiment, with the adhesive layers 111 arranged on both ends. m represents a natural number. The total number of base layers 112 and adhesive layers 111 is (2m+1). The rigid frame member 12A is made up of one layer. In other words, the number of layers constituting the pellicle according to the first embodiment is (2m+2).

[0049] As shown in Fig. 3, the calculation model 10X is a horizontally stacked model similar to the horizontally stacked laminate shown in Fig. 1. The layered structure of the calculation model 10X is the same as the layered structure of the pellicle frame according to the first embodiment.

[0050] 3, the symbol "h1" indicates the length indicating the thickness of the first layer (i.e., the thickness of one adhesive layer 111) counting from the surface S13 opposite to the contact surface S12 with which the soft frame member 11X of the hard frame member 12A comes into contact in the thickness direction of the calculation model 10X. The symbol "t1" indicates the length of the symbol "h1". The symbol "h2" is the length indicating the thickness of the first to second layers counting from the surface S13 opposite the contact surface S12 (i.e., the total thickness of one adhesive layer 111 and one base material layer 112). The symbol "t2" indicates the length obtained by subtracting h1 from h2. Sign “h” 2m " is the length indicating the thickness of the layer up to the (2m)th layer counting from the surface S13 opposite the contact surface S12 (i.e., the sum of the thicknesses of the m adhesive layers 111 and the m base material layers 112). Sign “h”2m+1 " is the length indicating the thickness of the (2m+1)th layer counting from the surface S13 opposite to the contact surface S12 (i.e., the thickness of the flexible frame member 11X). 2m +1 " is h 2m+1 From h 2m This indicates the length minus the original length.

[0051] The number of layers n of the pellicle frame according to the first embodiment (that is, the calculation model 10X) is the sum of the number of layers of the hard frame member 12A and the number of layers of the soft frame member 11X, where n is a natural number. When the number of layers of the hard frame member 12A is p, the number of layers of the pellicle frame according to the first embodiment (i.e., calculation model 10X) is obtained by adding p to 2m+1, which is the number of layers of the soft frame member 11X, to obtain (2m+1+p). p indicates a natural number. When the number of layers of the hard frame member 12A is 1, the number of layers of the pellicle frame according to the first embodiment (i.e., calculation model 10X) is obtained by adding 1 to 2m+1, which is the number of layers of the soft frame member 11X. The hard frame member 12A may be formed of two or more layers.

[0052] (1.2.2.1) Apparent Young's modulus of the pellicle frame The apparent Young's modulus of the pellicle frame (i.e., calculation model 10X) is calculated using the above formulas (iv) and (vi).

[0053] First, the neutral axis position (λ) is calculated using equation (iv). In the first embodiment, in the formula (iv), "n" corresponds to the number of layers of the calculation model 10X. n " is the number of layers of the rigid frame member 12A when p layers are used. 2m+1+p Corresponds to t1~t n " is the t1 to t of the calculation model 10X 2m+ 1+p Corresponds to "h1~h n " is the value obtained by multiplying h1 to h2 of the calculation model 10X when the number of layers of the rigid frame member 12A is one. 2m+2 Corresponds to t1~t n " is the t1 to t of the calculation model 10X2m+2 Corresponds to. The following describes the case where the rigid frame member 12A has one layer. "Ei when i is an odd number" corresponds to the Young's modulus of the adhesive layer 111 of the calculation model 10X. "Ei when i is an even number" corresponds, in principle, to the Young's modulus of the base material layer 112 of the calculation model 10X. However, "Ei when i is 2m+2" corresponds to the Young's modulus of the rigid frame member 12A of the calculation model 10X.

[0054] Next, the apparent Young's modulus (E) of the calculation model 10X is calculated using formula (vi). In the first embodiment, in the formula (vi), "h" is the h of the calculation model 10X. 2m+2 (i.e., the sum of the thickness of the flexible frame member 11X and the rigid frame member 12A). "n" corresponds to (2m+2) of the calculation model 10X. "E when i is an odd number" i " corresponds to the Young's modulus of the adhesive layer 111 of the calculation model 10X. "E when i is an even number i In principle, " corresponds to the Young's modulus of the base material layer 112 of the calculation model 10X. However, "E when i is 2m+2 i " corresponds to the Young's modulus of the rigid frame member 12A of the calculation model 10X. n " is the h1 to h of the calculation model 10X 2m+2 "λ" corresponds to the neutral axis position (λ) of the calculation model 10X calculated using formula (iv).

[0055] The calculated apparent Young's modulus (E) of the calculation model 10X is regarded as the apparent Young's modulus of the pellicle frame.

[0056] (1.2.2.2) Calculation method for bending stiffness The bending rigidity of the pellicle frame (that is, the calculation model 10X) is calculated using the above formulas (iv) and (v).

[0057] First, in the same manner as in the calculation of the apparent Young's modulus of the calculation model 10X, the neutral axis position (λ) of the calculation model 10X is calculated using equation (iv).

[0058] Next, the bending stiffness (EI) of the calculation model 10X is calculated using formula (v). In the first embodiment, in formula (v), "b" corresponds to the width of the calculation model 10X. The width of the calculation model 10X indicates the width of one side of the pellicle frame according to the first embodiment. In the first embodiment, the width of one side (short side) of the soft frame member 11X and the width of one side (short side) of the hard frame member 12A are the same. "n" corresponds to (2m+2) of the calculation model 10X. "E when i is an odd number" i " corresponds to the Young's modulus of the adhesive layer 111 of the calculation model 10X. "E when i is an even number i In principle, " corresponds to the Young's modulus of the base material layer 112 of the calculation model 10X. However, "E when i is 2m+2 i " corresponds to the Young's modulus of the rigid frame member 12A of the calculation model 10X. n " is the h1 to h of the calculation model 10X 2m+2 "λ" corresponds to the neutral axis position (λ) of the calculation model 10X calculated using formula (iv).

[0059] The calculated bending rigidity (EI) of the calculation model 10X is regarded as the bending rigidity of the pellicle frame. The closer the bending rigidity of the pellicle frame is to 0, the more effectively it can suppress distortion of the master plate caused by deformation of the pellicle frame.

[0060] The apparent Young's modulus and bending rigidity of the soft frame member 11X can be calculated in the same manner as the above-described method for calculating the Young's modulus of the pellicle frame and the method for calculating the bending rigidity of the pellicle frame, except that the hard frame member is not taken into consideration (i.e., calculation model 10Y is used instead of calculation model 10X). Calculation model 10Y has the same configuration as calculation model 10X, except that it does not include hard frame member 12A.

[0061] The Young's modulus and bending rigidity of the rigid frame member 12A can be calculated using the same method as the method for calculating the Young's modulus of the pellicle frame and the method for calculating the bending rigidity of the pellicle frame described above, except that the soft frame member 11X of the calculation model 10X is not taken into account.

[0062] (1.2.3) Ventilation path and ventilation filter The flexible frame member preferably includes an air passage, or an air passage and an air filter. The air passage passes through the flexible frame member. The air passage passes through the flexible frame member. The air filter is disposed in the air passage.

[0063] When the pellicle is attached to the master, the ventilation channel connects the internal space of the pellicle with the external space of the pellicle. The "internal space of the pellicle" refers to the space surrounded by the pellicle and the master. The "external space of the pellicle" refers to the space not surrounded by the pellicle and the master.

[0064] When a pellicle is attached to an original, a pressure difference may occur between the internal space of the pellicle and the external space of the pellicle. In this case, the pellicle membrane may sag or bulge. By including an air passage in the flexible frame member, it is possible to suppress the occurrence of a pressure difference between the internal space of the pellicle and the external space of the pellicle. The flexible frame member includes an air passage and an air filter, which suppresses the generation of a pressure difference between the internal space of the pellicle and the external space of the pellicle, and also suppresses the intrusion of foreign matter from the external space of the pellicle into the internal space of the pellicle. EUV exposure is performed in a vacuum atmosphere. If the area of ​​the air filter is sufficiently large, the time required to evacuate the internal space of the pellicle during EUV exposure is shortened.

[0065] The number of ventilation channels is not particularly limited, and at least one ventilation channel may be formed on each of the four side surfaces of the pellicle frame.

[0066] The ventilation filter is a filter that allows gas to pass through but prevents foreign matter such as dust from passing through. There are no restrictions on the type of ventilation filter as long as it can prevent foreign matter from entering the internal space of the pellicle from the external space of the pellicle, and examples include membrane ventilation filters such as HEPA (High Efficiency Particulate Air Filter) and ULPA (Ultra Low Penetration Air Filter), nonwoven fabric ventilation filters, ceramic ventilation filters, glass ventilation filters, sintered metal ventilation filters, ceramic ventilation filters, glass ventilation filters, sintered metal ventilation filters, and hollow paper ventilation filters. The ventilation filter preferably has an initial pressure loss of 100 Pa to 550 Pa and a particle retention rate of 99.7% to 100% for particles with particle diameters of 0.15 μm to 0.3 μm.

[0067] For the air vents and air filters, reference can be made to the air vents and air filters described in International Publication No. 2019-188445.

[0068] The method for fixing the ventilation filter is not particularly limited, and it is preferable that the ventilation filter be fixed to the soft frame member so as to cover the ventilation passage, and examples thereof include the first to fourth fixing methods. The first fixing method is a method in which one adhesive layer is divided into two in the thickness direction of the pellicle frame, and the ventilation filter is sandwiched between the adjacent divided adhesive layers, thereby fixing the ventilation filter. The second fixing method is a method of fixing the ventilation filter by bringing the ventilation filter into contact with at least one adhesive layer exposed in the ventilation passage. The third fixing method is a method of fixing the ventilation filter by contacting the ventilation filter with the same surface of one adhesive layer exposed in the ventilation channel. The fourth fixing method is a method of fixing the ventilation filter by welding the ventilation filter onto the same surface of one of the base material layers that is exposed in the ventilation path. Among these, the third and fourth fixing methods are preferred because they reduce the risk of creating areas in the air passage that are not covered by the ventilation filter (i.e., creating gaps) due to the unevenness of the ventilation filter, and the fourth fixing method is more preferred because it further reduces the generation of outgassing.

[0069] (1.2.4) Height of soft frame members The height of the flexible frame member (i.e., the length of the flexible frame member in the thickness direction) is not particularly limited. The height of the flexible frame member is preferably 0.9 mm to 2.0 mm, more preferably 1.4 mm to 1.9 mm, from the viewpoint of suppressing distortion caused by the tension of the pellicle film and suppressing distortion of the master caused by deformation of the pellicle frame.

[0070] The ratio of the height of the soft frame member to the height of the pellicle frame (hereinafter referred to as "height ratio of the soft frame member") is not particularly limited. The height ratio of the soft frame member is preferably 40% to 90%, more preferably 60% to 80%, from the viewpoint of suppressing distortion caused by the tension of the pellicle film and suppressing distortion of the master caused by deformation of the pellicle frame.

[0071] (1.2.5) Number of layers constituting the soft frame member The total number of base layers and adhesive layers contained in the soft frame member (hereinafter referred to as the "total number of layers") is not particularly limited as long as it is three or more layers, and is selected appropriately depending on the thickness of the base layers, the thickness of the adhesive layers, the size required for the pellicle frame, etc. If there is variation in the flatness of the base material layer and the adhesive layer, the variation in the flatness of the base material layer and the adhesive layer is canceled out by stacking these base material layers and adhesive layers. This improves the flatness of the flexible frame member. By not making the adhesive layer too thick, the variation in the flatness of the adhesive layer is reduced. From these perspectives, the total number of layers is preferably 5 or more, and more preferably 10 or more. The total number of layers is not particularly limited, and can be equal to or less than 40. From the viewpoint of simplifying the manufacturing process, the total number of layers is more preferably equal to or less than 30, and even more preferably equal to or less than 20. From these viewpoints, the number of layers stacked is preferably 3 to 40, more preferably 5 to 30, and even more preferably 10 to 20. From the viewpoint of providing an air passage in the region of the soft member, seven or more layers are more preferable, and nine or more layers are even more preferable. From these viewpoints, the number of layers is preferably 7 to 40, more preferably 7 to 30, and even more preferably 9 to 20.

[0072] The total thickness of the adhesive layers included in the flexible frame member is preferably 0.2 to 4 times the total thickness of the base layers included in the flexible frame member. This further reduces the restoring force caused by attachment to the master. In other words, distortion of the master caused by deformation of the pellicle frame can be further suppressed. Hereinafter, the ratio of the total thickness of the adhesive layers included in the soft frame member to the total thickness of the base material layers included in the soft frame member will be referred to as the "total thickness ratio of the adhesive layers." In order to facilitate handling, such as transportation, of the pellicle, the total thickness ratio of the adhesive layer is preferably 4 times or less, more preferably 3 times or less, and even more preferably 2 times or less, of the total thickness of the base material layer included in the soft frame member. From the viewpoint of reducing the rigidity of the pellicle frame and suppressing distortion of the original plate, the total thickness ratio of the adhesive layer is preferably 0.2 times or more, more preferably 0.6 times or more, even more preferably 0.8 times or more, and particularly preferably 1.0 times or more, relative to the total thickness of the base material layer included in the soft frame member. From these viewpoints, the total thickness ratio of the adhesive layer is preferably 0.2 to 3 times, more preferably 0.6 to 3 times, and even more preferably 0.8 to 2 times the total thickness of the base material layers included in the flexible frame member.

[0073] (1.2.6) Adhesive layer The adhesive layer has the following functions (a) to (c). (a) The adhesive layer disposed between two adjacent base layers in the thickness direction connects the base layers together. (b) One of the adhesive layers arranged at both ends in the thickness direction connects the soft frame member and the hard frame member. (c) The other adhesive layer of the adhesive layers arranged at both ends in the thickness direction connects the pellicle frame and the master plate.

[0074] (1.2.6.1) Thickness of adhesive layer The thickness of each adhesive layer (hereinafter referred to as the "single layer thickness of the adhesive layer") is preferably 0.01 mm or more and 0.5 mm or less, which can further reduce deformation of the adhesive layer layer in the punching step of the pellicle manufacturing method of the present disclosure described below, and further reduce the rigidity of the adhesive layer, thereby further suppressing distortion of the master plate caused by deformation of the pellicle frame. In order to minimize deformation of the adhesive layer during the punching process of the pellicle manufacturing method described below, the single layer thickness of the adhesive layer is preferably 0.5 mm or less, more preferably 0.25 mm or less, and even more preferably 0.2 mm or less. In order to further reduce the rigidity of the adhesive layer and further suppress the restoring force caused by attachment to the original plate, the single layer thickness of the adhesive layer is preferably 0.01 mm or more, more preferably 0.03 mm or more, and even more preferably 0.05 mm or more.

[0075] (1.2.6.2) Adhesive layer material The Young's modulus of the adhesive layer is preferably 0.01 MPa to 1.0 MPa, which further reduces the rigidity of the adhesive layer and further suppresses distortion of the master plate caused by deformation of the pellicle frame. The Young's modulus of the adhesive layer is more preferably 0.8 MPa or less, and even more preferably 0.6 MPa or less, from the viewpoint of further reducing the rigidity of the adhesive layer and further suppressing the restoring force caused by attachment to the master. The Young's modulus of the adhesive layer is not particularly limited, but is more preferably 0.02 MPa or more, and even more preferably 0.04 MPa or more. Examples of materials with a Young's modulus of 1.0 MPa or less include acrylic resin, silicone resin, and styrene-butadiene resin. Examples of materials having a Young's modulus of 0.8 MPa or less include acrylic resin, silicone resin, and styrene-butadiene resin. Examples of materials with a Young's modulus of 0.6 MPa or less include acrylic resin, silicone resin, and styrene-butadiene resin. The Young's modulus of the adhesive layer is measured by a three-point bending test (JIS K7171).

[0076] The material of the adhesive layer is not particularly limited, and examples thereof include acrylic resin, silicone resin, styrene butadiene resin, urethane resin, olefin resin, epoxy resin, polyimide resin, and hydrogenated styrene resin. In particular, the material of the adhesive layer preferably contains an acrylic resin or a silicone resin from the viewpoint of further reducing the rigidity of the soft frame member, and preferably contains an acrylic resin from the viewpoint of further suppressing the amount of outgassing.

[0077] (1.2.6.3) Surface of adhesive layer It is preferable that the surface of the adhesive layer satisfies any one of the following (A) to (C). (A) an inorganic layer is formed on at least the inner wall surface of the adhesive layer; (B) At least the inner wall surface of the adhesive layer satisfies the following formula (1): (C) At least the inner wall surface of the adhesive layer satisfies the following formula (2):

[0078] Equation (1):([CNO - 2s ] / [CNO - 50s ])≧2.00 In the formula (1), [CNO - 2s ] is a method for measuring a first deep portion having a first depth from the surface of the adhesive layer by time-of-flight secondary ion mass spectrometry (TOF-SIMS) (hereinafter referred to as "TOF-SIMS") using an ion source of Bi3 ++ CNO analyzed using a primary ion gun with an irradiation area of ​​100 μm × 100 μm. - The normalized intensity of The first depth is formed by irradiating a 600 μm square area of ​​the surface with a sputter ion gun, which is an argon gas cluster ion beam (Ar-GCIB) with a beam voltage of 20 kV and a beam current of 20 nA, for a cumulative period of 2 seconds. Hereinafter, a sputter ion gun that is an argon gas cluster ion beam with a beam voltage of 20 kV and a beam current of 20 nA will be simply referred to as a "sputter ion gun (Ar-GCIB)." [CNO - 50s ] is a CNO obtained by analyzing the second deep portion of the second depth by TOF-SIMS. - indicates the normalized intensity of The second depth is formed by irradiating the area with the sputter ion gun for a cumulative period of 50 seconds. The normalized intensity is the ratio of the peak intensity of the component to the total intensity of the peaks whose intensity peak positions are between 45 (m / z) and 2000 (m / z) detected by TOF-SIMS.

[0079] Formula (2):([C3 - 2s ] / [C3 - 50s ])≧1.10 In formula (2), [C3 - 2s ] is the C3 obtained by analyzing the first deep part by TOF-SIMS. - indicates the normalized intensity of [C3 - 50s ] is the C3 obtained by analyzing the second deep part by TOF-SIMS. - The normalized intensity of

[0080] In the present disclosure, the "surface of the adhesive layer" includes the inner wall surface of the adhesive layer and the outer wall surface of the adhesive layer. TOF-SIMS is a technique in which a solid sample is irradiated with a primary ion gun (primary ions), and the ions (secondary ions) emitted from the surface of the solid sample by a collision cascade are mass-separated by utilizing the difference in their flight times. TOF-SIMS allows the generation and analysis of secondary ions at desired depths of a solid sample by irradiating the sample with a sputtering gun (Ar-GCIB) to etch the surface of the solid sample and then analyzing the resulting surface. Therefore, TOF-SIMS can be used to quantitatively evaluate changes in functional groups and other components in the depth direction of a solid sample. TOF-SIMS has high mass resolution, e.g., C3H3O + and C4H7 + can be analyzed separately.

[0081] When the adhesive layer satisfies any one of (A) to (C), outgassing is less likely to occur from the pellicle of the present disclosure, which will be described later. The outgassing includes gas derived from water and gas derived from components contained in the adhesive layer. The outgassing includes volatile hydrocarbons (molecular weight: 45 to 100) and non-volatile hydrocarbons (molecular weight: 101 to 200). This is presumably due mainly to the following reasons. Outgassing occurs when, for example, the adhesive layer is damaged when exposed to EUV light directly. During EUV exposure, the EUV light can scatter on the surface of the master.

[0082] In the case of condition (A), the scattered EUV light directly strikes the inorganic layer, but not the inner wall surface of the adhesive layer. This is thought to enable the pellicle of the present disclosure to more effectively suppress outgassing than when no inorganic layer is formed on the inner wall surface of the adhesive layer.

[0083] In the case of condition (B), satisfying formula (1) indicates that the surface of the adhesive layer has been surface-modified with a compound derived from a nitrogen functional group. The compound derived from a nitrogen functional group contributes to the immobilization of hydrocarbons (raising the boiling point) or acts as a gas barrier film that inhibits gas permeation from inside the adhesive layer. Therefore, it is presumed that outgassing can be suppressed.

[0084] The present inventors performed depth profile analysis of the surface of the surface-treated adhesive layer using TOF-SIMS. As a result, the present inventors experimentally confirmed that the normalized intensity of secondary ions changes significantly up to a depth of about 80 nm from the surface of the adhesive layer, but does not change significantly at depths deeper than about 80 nm from the surface of the adhesive layer. The depth of about 80 nm from the surface of the adhesive layer is formed, for example, by irradiating the surface of the adhesive layer with a sputtering gun (Ar-GCIB) for a cumulative total of 10 seconds. When the surface of the adhesive layer is irradiated with a sputtering gun (Ar-GCIB) for a cumulative total of 2 seconds, the surface of the adhesive layer is etched, and the depth of the first deep portion becomes approximately 16 nm from the surface of the adhesive layer. By analyzing the first deep portion with TOF-SIMS, it is possible to detect secondary ions (noise) caused by foreign matter attached to the surface of the adhesive layer while detecting secondary ions caused by functional groups, etc. affected by the surface treatment. In other words, by analyzing the first deep portion with TOF-SIMS, it is possible to quantitatively and accurately grasp the functional groups, etc. on the surface of the adhesive layer that has been subjected to surface treatment. When the surface of the adhesive layer was irradiated with a sputtering gun (Ar-GCIB) for a cumulative 50 seconds, the surface of the adhesive layer was etched, and the depth of the second deep portion was approximately 400 nm from the surface of the adhesive layer. By analyzing the second deep portion with TOF-SIMS, secondary ions originating from functional groups, etc., that were hardly affected by the surface treatment, could be detected. In other words, the analysis results of the second deep portion can be considered to quantitatively represent the functional groups, etc., on the surface of the adhesive layer before the surface treatment was applied. ([CNO - 2s ] / [CNO - 50s ]) is a CNO - Therefore, satisfying formula (1) indicates that the inner wall surface of the adhesive layer has been modified.

[0085] In the case of condition (C), satisfying formula (2) indicates that the surface layer of the inner wall surface of the adhesive layer is carbonized. The carbonized surface layer of the inner wall surface of the adhesive layer becomes a gas barrier film that prevents gas from permeating from inside the adhesive layer. Therefore, it is presumed that the generation of outgassing can be suppressed.

[0086] (1.2.6.3.1) Condition (A) The inorganic layer may be formed on the inner wall surface of the adhesive layer, or may be formed on both the inner wall surface and the outer wall surface of the adhesive layer. There are no limitations on the material for the inorganic layer as long as it can suppress outgassing, and it may be, for example, a material (metal, ceramic, etc.) that has low transmittance to EUV light. The metal that can be used for the inorganic layer is preferably any one metal selected from the group consisting of aluminum, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, rubidium, strontium, yttrium, zirconia, niobium, molybdenum, ruthenium, rhodium, palladium, silver, hafnium, tantalum, tungsten, platinum, and gold. The inorganic layer may be an alloy or oxide using two or more elements selected from these.

[0087] (1.2.6.3.2) Condition (B) The adhesive layer only needs to have an inner wall surface that satisfies formula (1), and both the inner and outer wall surfaces of the adhesive layer may satisfy formula (1).

[0088] CNO in the adhesive layer analyzed by TOF-SIMS - The normalized strength of depends on the material of the adhesive layer, whether or not plasma nitriding treatment has been performed, and the like. CNO - It is presumed that this is mainly due to the amide bond or urethane bond contained in the adhesive layer and the nitrogen functional group introduced into the adhesive layer by the plasma nitriding treatment.

[0089] ([CNO - 2s ] / [CNO - 50s ]) can be, for example, 500 or less, preferably 300 or less, more preferably 100 or less, and further preferably 10 or less, from the viewpoint of suppressing an increase in the cost of plasma nitriding treatment. ([CNO -2s ] / [CNO - 50s ]) can be, for example, 2.00 or more, preferably 3.00 or more, more preferably 10.0 or more, and even more preferably 100 or more, from the viewpoint of further suppressing the generation of outgassing by modifying the surface layer of the adhesive layer to a compound derived from a nitrogen functional group.

[0090] The surface of the adhesive layer is modified to a compound derived from nitrogen functional groups to suppress outgassing, and [CNO - 2s The content of] is preferably 0.001% or more, more preferably 0.010% or more, even more preferably 0.100% or more, and particularly preferably 1.000% or more, relative to all fragments detected by TOF-SIMS measurement at the first depth. In order to prevent the increase in the cost of plasma nitriding, - 2s The content of ] is preferably 5.000% or less, more preferably 1.000% or less, and even more preferably 0.1 00% or less, and particularly preferably 0.010% or less. The surface of the adhesive layer is modified to a compound derived from nitrogen functional groups to suppress outgassing, and [CNO - 2s The normalized intensity of [(x,y)] is preferably 0.01 or more, more preferably 0.03 or more, even more preferably 0.10 or more, and particularly preferably 1.00 or more. In order to prevent the increase in the cost of plasma nitriding, - 2s The content ratio of] is preferably 3.00 or less, more preferably 1.00 or less, and even more preferably 0.30 or less, Particularly preferably, it is 0.03 or less.

[0091] As a method for making the inner wall surface etc. of the adhesive layer satisfy the formula (1), for example, a method of subjecting the inner wall surface etc. of the adhesive layer to plasma nitriding treatment can be mentioned. In particular, when the adhesive layer does not contain nitrogen atoms, if the plasma nitriding treatment is performed on the inner wall surface of the adhesive layer, ([CNO -2s ] / [CNO - 50s ]) becomes dramatically higher. For example, ([CNO - 2s ] / [CNO - 50s ]) is 10 or more. This is because, while nitrogen atoms are introduced into the first deep portion by the plasma nitridation treatment, it is difficult for nitrogen atoms to be introduced into the second deep portion, and ([CNO - 2s ] / [CNO - 50s ]) is the denominator of [CNO - 50s This is presumably due to the fact that the number of people receiving medical care remains low.

[0092] (1.2.6.3.3) Condition (C) The adhesive layer only needs to satisfy the formula (2) on its inner wall surface, and both the inner wall surface and the outer wall surface of the adhesive layer may satisfy the formula (2).

[0093] C3 in the adhesive layer analyzed by TOF-SIMS - The normalized strength of depends on the material of the adhesive layer, whether EUV irradiation treatment has been performed, etc. C3 - This is presumably due to carbonization of the inner wall surface of the adhesive layer caused by surface treatment, which includes plasma nitriding and extreme ultraviolet irradiation (hereinafter referred to as "EUV irradiation").

[0094] When the inner wall surface of the adhesive layer satisfies formula (2), the surface layer of the adhesive layer is carbonized, the generation of outgassing is suppressed, and the permeation of gas from inside the adhesive layer can be suppressed.

[0095] ([C3 - 2s ] / [C3 - 50s ]) can be, for example, 10.0 or less, preferably 5.0 or less, more preferably 3.0 or less, and even more preferably 2.0 or less, from the viewpoint of suppressing an increase in the cost of EUV irradiation treatment. ([C3 - 2s] / [C3 - 50s ]) can be, for example, 1.10 or more, preferably 1.20 or more, more preferably 1.40 or more, and even more preferably 2.00 or more, from the viewpoint of carbonizing and modifying the surface layer of the adhesive layer to suppress the generation of outgassing.

[0096] As a method for making the inner wall surface etc. of the adhesive layer satisfy the formula (2), for example, a method of subjecting the inner wall surface etc. of the adhesive layer to EUV irradiation treatment can be mentioned. When the inner wall surface of the adhesive layer is subjected to EUV irradiation treatment, the surface of the inner wall surface absorbs the EUV and becomes hot, which makes the surface of the inner wall surface that has been subjected to EUV irradiation treatment more susceptible to carbonization.

[0097] (1.2.7) Base material layer The base layer allows the formation of a flexible frame member without forming a thick adhesive layer by thickly applying an adhesive. By including at least one base layer in the flexible frame member, the thickness of the adhesive layer included in the flexible frame member is thinner than a thick adhesive layer formed by thickly applying an adhesive. Therefore, the adhesive layer included in the flexible frame member can be formed by drying in a shorter time. Furthermore, significant deformation of the pellicle frame can be suppressed, making it easier to handle, such as for transportation, as a pellicle. The upper limit of the thickness of a single commercially available optical adhesive sheet (OCA: Optical Clear Adhesive) is approximately 250 μm. Therefore, the thickness of the adhesive layer included in the flexible frame member can be adjusted to meet market needs.

[0098] (1.2.7.1) Thickness of the substrate layer The thickness of each base layer (hereinafter referred to as the "single layer thickness of the base layer") is preferably 2.5 mm or less, which facilitates the execution of the punching step in the manufacturing method of the pellicle, which will be described later, and also facilitates the execution of the lamination step in the manufacturing method of the pellicle, which will be described later. In order to facilitate the execution of the punching step of the pellicle manufacturing method described below, the single layer thickness of the substrate layer is preferably 2.5 mm or less, more preferably 2.0 mm or less, even more preferably 1.0 mm or less, and particularly preferably 0.5 mm or less. From the viewpoint of facilitating the lamination step of the pellicle manufacturing method described below, the single layer thickness of the substrate layer is preferably 0.01 mm or more, more preferably 0.05 mm or more, and even more preferably 0.10 mm or more.

[0099] (1.2.7.2) Material of the base layer The Young's modulus of the base layer is preferably 2 GPa to 200 GPa, which makes it easier to carry out the punching step in the manufacturing method of the pellicle and prevents large deformation of the pellicle frame, making the pellicle easier to handle during transportation and the like. From the viewpoint of suppressing distortion of the master plate due to deformation of the pellicle frame, the Young's modulus of the base layer is preferably 200 GPa or less, more preferably 110 GPa or less, even more preferably 50 GPa or less, and particularly preferably 10 GPa or less. From the viewpoint of facilitating the execution of the punching step in the manufacturing method of a pellicle and suppressing large deformation of the pellicle frame, thereby making the pellicle easier to handle for transportation, etc., the Young's modulus of the base layer is preferably 0.1 GPa or more, more preferably 0.5 GPa or more, and even more preferably 1 GPa or more. From these viewpoints, the Young's modulus of the base layer is preferably 0.1 GPa to 110 GPa, more preferably 0.5 GPa to 50 GPa, and particularly preferably 1 GPa to 10 GPa. Examples of materials with a Young's modulus of 110 GPa or less include glass, stainless steel, aluminum, titanium, titanium alloys, silicon, polyethylene terephthalate resin, polyethylene resin, polypropylene resin, polyimide resin, polyethylene naphthalate resin, polycarbonate resin, polyphenylene sulfide resin, fluororesin, polyether ether ketone resin, and polyether sulfone resin. Examples of materials with a Young's modulus of 50 GPa or less include polyethylene terephthalate resin, polyethylene resin, polypropylene resin, polyimide resin, polyethylene naphthalate resin, polycarbonate resin, polyphenylene sulfide resin, fluororesin, polyether ether ketone resin, and polyether sulfone resin. Examples of materials having a Young's modulus of 10 GPa or less include polyethylene terephthalate resin, polyethylene resin, polypropylene resin, polyimide resin, polyethylene naphthalate resin, polycarbonate resin, polyphenylene sulfide resin, fluororesin, polyether ether ketone resin, polyether sulfone resin, and aramid resin. The Young's modulus of the base material layer is measured by a tensile test (JIS G0567J). However, if the base material layer is made of resin, the value is measured by a three-point bending test (JIS K7171). Whether the material of the material layer is resin or not can be determined by whether the material of the hard frame member undergoes thermal decomposition at 550°C. When evaluating a laminated frame, it may be peeled off from the laminated state and analyzed.

[0100] The Young's modulus of the base layer is preferably 10,000 to 9,000,000 times that of the adhesive layer. This further reduces the restoring force caused by attachment to the master. In other words, distortion of the master caused by deformation of the pellicle frame can be further suppressed. Hereinafter, the ratio of the Young's modulus of the base layer to the Young's modulus of the adhesive layer will be referred to as the "Young's modulus ratio of the base layer." From the viewpoint of further reducing the restoring force caused by attachment to the master, the Young's modulus ratio of the base layer is more preferably 3 million times or less (for example, when the base layer is made of titanium), even more preferably 1 million times or less, and particularly preferably 200,000 times or less (for example, when the base layer is made of polyethylene terephthalate resin). From the viewpoint of facilitating the execution of the lamination step in the manufacturing method of a pellicle, which will be described later, the Young's modulus ratio of the base layer is more preferably 50,000 times or more, and even more preferably 300,000 times or more. From the viewpoint of further reducing the restoring force caused by attachment to the master and from the viewpoint of facilitating the execution of the lamination step in the manufacturing method of the pellicle, the magnification is preferably 50,000 to 3,000,000 times, and more preferably 50,000 to 200,000 times. When the number of base material layers with different Young's moduli among the multiple base material layers included in the soft frame member is multiple, the Young's modulus of the base material layer with the smallest Young's modulus among the multiple base material layers with different Young's moduli is defined as the "Young's modulus of the base material layer." When the number of adhesive layers with different Young's moduli among the multiple adhesive layers included in the soft frame member is multiple, the Young's modulus of the adhesive layer with the largest Young's modulus among the multiple adhesive layers with different Young's moduli is defined as the "Young's modulus of the adhesive layer."

[0101] The material of the substrate layer is not particularly limited, and examples thereof include metals, ceramics, and resins. Examples of metals that can be used for the substrate layer include aluminum, titanium, and stainless steel. Examples of ceramics that can be used for the substrate layer include silicon and glass. Examples of resins that can be used for the base layer include polyethylene resin, polypropylene resin, polyethylene terephthalate resin, polyimide resin, polyethylene naphthalate resin, polystyrene resin, acrylic resin, polycarbonate resin, polyimide resin, polyphenylene sulfide resin, fluororesin, polyether ether ketone resin, polyether sulfone resin, and aramid resin. From the viewpoint of forming the flexible frame member in a good shape, the material of the base material layer is preferably a material that can be slit coated or spin coated, and preferred examples of such materials include acrylic resin, silicone resin, and styrene butadiene resin. From the viewpoint of facilitating the processing of the shape of the flexible frame member, the material of the base material layer is preferably a resin. If the material of the base material layer is a resin, notches and openings can be formed by punching. In particular, the material of the base material layer preferably contains polyethylene terephthalate resin, polyethylene naphthalate resin, or polyimide resin.

[0102] (2) Pellicle The pellicle of the present disclosure comprises the pellicle frame of the present disclosure and a pellicle membrane supported by a rigid frame member. The pellicle of the present disclosure is suitable for use in EUV exposure.

[0103] (2.1) Pellicle membrane The pellicle film prevents foreign matter from adhering to the surface of the original and allows the exposure light to pass through during exposure. Foreign matter includes dust. The exposure light can be deep ultraviolet (DUV) light, EUV light, or the like.

[0104] The pellicle film covers the entire opening of the exposure through-hole of the pellicle frame on the hard frame member side. The pellicle film may be supported on the pellicle frame member directly or via an adhesive layer. The adhesive layer may be a cured product of a known adhesive.

[0105] The thickness of the pellicle film is preferably 2 nm or more and 200 nm or less. The material of the pellicle film is not particularly limited, and examples thereof include carbon-based materials, SiN, polysilicon, and a laminated structure in which a plurality of layers thereof are deposited. Carbon-based materials include graphene and carbon nanotubes (hereinafter referred to as "CNTs"). In particular, the material of the pellicle film preferably contains CNTs. The CNTs may be single-wall CNTs or multi-wall CNTs. When the carbon content of the pellicle membrane is 40 mass % or more, the pellicle membrane can be connected to the rigid frame member by van der Waals forces without an adhesive layer. The pellicle membrane may have a nonwoven structure, which may be formed, for example, from fiber-shaped CNTs.

[0106] (2.2) Protective film The pellicle of the present disclosure may optionally be provided with a protective film (liner). The protective film protects at least the surface of the adhesive layer that comes into contact with the original plate, and is peelable from the adhesive layer. The thickness of the protective film is preferably 5 μm to 500 μm, more preferably 30 μm to 200 μm. Examples of the material for the protective film include polyester. The surface of the protective film that comes into contact with the adhesive layer may be coated with a release agent, such as a silicone-based release agent or a fluorine-based release agent.

[0107] (2.3) Exposed master The pellicle of the present disclosure may be provided on an exposure master. The exposure master includes a master and a pellicle. The master is a master for a circuit pattern. The master has a pattern. The pellicle is attached to the surface of the master that has the pattern.

[0108] The master does not necessarily have to have a support substrate, a reflective layer, and an absorber layer stacked in this order. The absorber layer partially absorbs light (e.g., EUV), forming a desired image on a sensitive substrate (e.g., a semiconductor substrate with a photoresist film). Examples of the reflective layer include a multilayer film of molybdenum (Mo) and silicon (Si). The absorber layer may be made of a material that is highly absorbent of EUV and other light. Examples of materials that are highly absorbent of EUV and other light include chromium (Cr) and tantalum nitride.

[0109] (2.4) Exposure equipment The pellicle of the present disclosure may be included in an exposure apparatus. The exposure apparatus includes a light source, the above-described exposure master, and an optical system. The light source emits exposure light. The optical system guides the exposure light emitted from the light source to the exposure master. The exposure master is positioned so that the exposure light emitted from the light source passes through a pellicle film and is irradiated onto the master. The exposure device is capable of forming fine patterns (e.g., line widths of 32 nm or less) using EUV and other technologies, and can also perform pattern exposure with reduced resolution problems caused by foreign matter, even when using EUV, which is prone to resolution problems caused by foreign matter. The exposure light is preferably EUV. Because EUV has a short wavelength, it is easily absorbed by gases such as oxygen or nitrogen. Therefore, exposure with EUV light is performed in a vacuum environment.

[0110] (2.5) An example of a pellicle Next, an example of a pellicle according to the present disclosure will be described with reference to Figures 4 to 6. Figure 4 is a cross-sectional view of a pellicle according to a second embodiment of the present disclosure.

[0111] (2.5.1) Second embodiment As shown in FIG. 4, the pellicle 1 according to the second embodiment of the present disclosure is attached to the surface of an original plate when in use. The pellicle 1 according to the second embodiment of the present disclosure comprises a pellicle frame 10A, a pellicle film 20, and an adhesive layer 21. The pellicle film 20 is supported by the pellicle frame 10A via the known adhesive layer 21.

[0112] Hereinafter, the surface direction D1 of the pellicle film 20 will be referred to as the "surface direction D1", and the direction D2 perpendicular to the surface direction of the pellicle film 20 will be referred to as the "thickness direction D2".

[0113] The pellicle frame 10A is a rectangular cylindrical object. The pellicle frame 10A has an exposure through-hole THA. The exposure through-hole THA linearly penetrates the pellicle frame 10A along the thickness direction D2 at the center of the pellicle frame 10A in the planar direction D1.

[0114] The pellicle frame 10A is an assembled product, and includes a soft frame member 11A and a hard frame member 12A. The soft frame member 11A and the hard frame member 12A are stacked in the thickness direction D2 of the pellicle frame 10A. The Young's modulus of the hard frame member 12A is higher than the apparent Young's modulus of the soft frame member 11 A. The Young's modulus of the hard frame member 12A is 25 GPa or more.

[0115] The soft frame member 11A is a rectangular cylindrical object, similar to the pellicle frame 10A. The soft frame member 11A has a through-hole TH11. The through-hole TH11 constitutes a part of the exposure through-hole THA of the pellicle frame 10A. In the second embodiment, the flexible frame member 11A is formed by alternately laminating six adhesive layers 111 and five base layers 112 in the thickness direction D2 so that the adhesive layers 111 are disposed on both ends. In the second embodiment, the flexible frame member 11A includes four air passages THB and four ventilation filters 113. One air passage THB is formed on each of the four side surfaces of the pellicle frame 10A. The air passages THB extend nonlinearly from the inner wall surface S10A to the outer wall surface S10B of the pellicle frame 10A in the planar direction D1. One ventilation filter 113 is disposed in one air passage THB. The ventilation filter 113 is fixed inside the soft frame member 11A and covers the ventilation channel THB. More specifically, in the second embodiment, the ventilation filter 113 is fixed by being in contact with the same surface of one adhesive layer 111 exposed inside the ventilation channel THB. The ventilation filter 113 is, for example, a HEPA ventilation filter.

[0116] The hard frame member 12A is a rectangular cylindrical object, similar to the pellicle frame 10A. The hard frame member 12A has a through-hole TH12. The through-hole TH12 constitutes a part of the exposure through-hole THA of the pellicle frame 10A.

[0117] In the second embodiment, the thickness of the pellicle 1 is, for example, 2.375 mm. The length L10 of one side of the pellicle frame 10A is, for example, 150 mm. The width W10 of one side of the pellicle frame 10A is, for example, 4.0 mm. The thickness of the flexible frame member 11A is, for example, 1.650 mm. The single layer thickness of the adhesive layer 111 is, for example, 0.236 mm. The material of the adhesive layer 111 is, for example, acrylic resin (Young's modulus: 0.045 MPa). The single layer thickness of the base layer 112 is, for example, 0.236 mm. The material of the base layer 112 is, for example, polyethylene terephthalate resin (Young's modulus: 4 GPa). The thickness of the rigid frame member 12A is, for example, 0.725 mm.

[0118] The pellicle 1 is suitable for use in EUV exposure. EUV exposure is performed in a vacuum atmosphere because EUV light is easily absorbed by gases such as oxygen and nitrogen.

[0119] (2.5.2) Third embodiment A pellicle frame according to a third embodiment of the present disclosure will be described with reference to Fig. 5. Fig. 5 is a cross-sectional view of the pellicle frame according to the third embodiment of the present disclosure.

[0120] A pellicle frame 10B according to the third embodiment of the present disclosure is similar to the pellicle frame 10A according to the second embodiment, except that the method of fixing the ventilation filter 113 is different. The pellicle frame 10B is an assembled product and includes a soft frame member 11B and a hard frame member 12A. The soft frame member 11B and the hard frame member 12A are stacked in the thickness direction D2. The Young's modulus of the hard frame member 12A is higher than the apparent Young's modulus of the soft frame member 11B. The Young's modulus of the hard frame member 12A is 25 GPa or more.

[0121] The soft frame member 11B is a rectangular cylindrical object, similar to the pellicle frame 10A. In the third embodiment, the soft frame member 11B is formed by alternately stacking six adhesive layers 111 and five base layers 112 in the thickness direction D2, with the adhesive layers 111 disposed on both ends. In the third embodiment, the soft frame member 11B includes four air passages THB and four air passage filters 113. One air passage filter 113 is disposed in one air passage THB.

[0122] The ventilation filter 113 is fixed inside the flexible frame member 11B and covers the ventilation path THB. Specifically, in the third embodiment, one of the plurality of adhesive layers 111 has an adhesive portion 111a and an adhesive portion 111b, which are obtained by dividing the adhesive layer 111 into two in the thickness direction D2. The ventilation filter 113 is fixed by being sandwiched between the adjacent divided adhesive portions 111a and 111b. The ventilation filter 113 is, for example, a HEPA ventilation filter.

[0123] (2.5.3) Fourth embodiment A pellicle frame according to a fourth embodiment of the present disclosure will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view of the pellicle frame according to the fourth embodiment of the present disclosure.

[0124] A pellicle frame 10C according to the fourth embodiment of the present disclosure is similar to the pellicle frame 10A according to the second embodiment, except that the method of fixing the ventilation filter 113 is different. The pellicle frame 10C is an assembled product and includes a soft frame member 11C and a hard frame member 12A. The soft frame member 11C and the hard frame member 12A are stacked in the thickness direction D2. The Young's modulus of the hard frame member 12A is higher than the apparent Young's modulus of the soft frame member 11C. The Young's modulus of the hard frame member 12A is 25 GPa or more.

[0125] The soft frame member 11C is a rectangular cylindrical object, similar to the pellicle frame 10A. In the fourth embodiment, the soft frame member 11C is formed by alternately stacking six adhesive layers 111 and five base layers 112 in the thickness direction D2, with the adhesive layers 111 disposed on both ends. In the fourth embodiment, the soft frame member 11C includes four air passages THB and four air passage filters 113. One air passage filter 113 is disposed in one air passage THB.

[0126] The ventilation filter 113 is fixed inside the soft frame member 11C and covers the ventilation channel THB. More specifically, in the fourth embodiment, the ventilation filter 113 is fixed by being welded to the same surface of one of the base material layers 112 that is exposed inside the ventilation channel THB. The ventilation filter 113 is, for example, a HEPA ventilation filter.

[0127] (2.5.4) Fifth embodiment A pellicle frame according to a fifth embodiment of the present disclosure will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view of the pellicle frame according to the fifth embodiment of the present disclosure.

[0128] The pellicle frame 10D according to the fifth embodiment of the present disclosure is similar to the pellicle frame 10A according to the second embodiment, except that the configuration of the hard frame member and the soft frame member and the method of fixing the ventilation filter 113 are different. The pellicle frame 10D is an assembled product and includes a soft frame member 11D and a hard frame member 12D. The soft frame member 11D and the hard frame member 12D are stacked in the thickness direction D2. The Young's modulus of the hard frame member 12D is higher than the apparent Young's modulus of the soft frame member 11D. The Young's modulus of the hard frame member 12D is 25 GPa or more.

[0129] The soft frame member 11D and the hard frame member 12D are rectangular tubular objects, similar to the pellicle frame 10A. In the fifth embodiment, the soft frame member 11D is formed by alternately stacking four adhesive layers 111 and three base layers 112 in the thickness direction D2, with the adhesive layers 111 disposed on both ends. The hard frame member 12D is formed by stacking three hard layers 121 in the thickness direction D2. In the fifth embodiment, the soft frame member 11D includes four air passages THB and four air passage filters 113. One air passage filter 113 is disposed in one air passage THB.

[0130] The ventilation filter 113 is fixed inside the soft frame member 11D and covers the ventilation channel THB. Specifically, in the fifth embodiment, the ventilation filter 113 is fixed by contacting it with the same surface of one adhesive layer 111 exposed inside the ventilation channel THB. The ventilation filter 113 is, for example, a HEPA ventilation filter.

[0131] (3) Pellicle manufacturing method The method for manufacturing a pellicle of the present disclosure includes the steps of preparing the hard frame member, a lamination step of alternately laminating at least one base layer sheet and a plurality of adhesive layer layers in the thickness direction to form a laminate, a punching step of punching through the laminate so as to form an exposure through hole along the thickness direction to form the soft frame member, and a connection step of connecting the hard frame member to the soft frame member. A laminate is formed by alternately stacking a base layer sheet and a plurality of adhesive layer layers in the thickness direction, and then punching through the laminate so as to form an exposure through hole along the thickness direction, thereby making it possible to manufacture a pellicle frame that minimizes misalignment of the openings even with multiple laminates.

[0132] In the present disclosure, the term "layer for adhesive layer" includes a sheet for adhesive layer and a coating layer for adhesive layer obtained by applying a pressure-sensitive adhesive for adhesive layer.

[0133] The method for manufacturing a pellicle disclosed herein has the above-described configuration, and therefore a pellicle can be obtained that suppresses distortion caused by the tension of the pellicle film and suppresses distortion of the master plate caused by deformation of the pellicle frame.

[0134] The laminating step and the punching step are performed in this order. The preparing step may be performed before the laminating step, after the laminating step and before the punching step, or after the punching step. The connecting step is performed after the punching step and the preparing step.

[0135] The method for manufacturing a pellicle of the present disclosure preferably further includes at least one of a surface treatment step described below and an air passage processing step described below. If the method for manufacturing a pellicle of the present disclosure includes the air passage processing step, the method for manufacturing a pellicle of the present disclosure preferably further includes a filter fixing step described below. The surface treatment step is performed after the punching step, the air passage processing step is performed before the lamination step, and the filter fixing step is performed after the air passage processing step and before the lamination step.

[0136] A pellicle manufacturing method according to an embodiment of the present disclosure will be described below. The method for manufacturing a pellicle according to this embodiment includes a surface treatment step, an air passage processing step, and a filter fixing step in addition to the lamination step, punching step, preparation step, and connection step. The air passage processing step, filter fixing step, lamination step, punching step, surface treatment step, preparation step, and connection step are performed in this order. The adhesive layer is a sheet for an adhesive layer.

[0137] (3.1) Ventilation channel processing process The method for manufacturing a pellicle of this embodiment includes an air passage processing step, which results in a pellicle in which the soft frame member includes an air passage.

[0138] In the air passage processing step, at least one base layer raw sheet and the plurality of adhesive layer raw sheets are processed to form air passages, thereby forming at least one base layer sheet and a plurality of adhesive layer sheets. The air passage processing step is carried out before the lamination step.

[0139] In the present disclosure, the term "raw sheet for base layer" refers to a solid sheet of material for the base layer. In the present disclosure, the term "unprocessed sheet for adhesive layer" refers to a solid sheet of material for the adhesive layer. In the present disclosure, the term "sheet for base layer" refers to the material of the base layer. The sheet for base layer may be a sheet processed to form an air passage, or may be a solid sheet. In the present disclosure, the term "sheet for adhesive layer" refers to a material for the adhesive layer. The sheet for adhesive layer may be a sheet processed to form an air passage, or may be a solid sheet.

[0140] The raw material for the base layer is the same as the material for the base layer. The raw material for the adhesive layer is the same as the material for the adhesive layer.

[0141] The ventilation path is formed by forming openings in at least one raw sheet for the base layer and a plurality of raw sheets for the adhesive layer, and then laminating these. The number of raw base layer sheets and raw adhesive layer sheets to be processed is appropriately selected depending on the shape of the air passage formed in the flexible frame member, etc. For example, each of the raw base layer sheets and raw adhesive layer sheets may be processed independently, or the raw adhesive layer sheet may be laminated on at least one main surface of the raw base layer sheet and processed. The processing method for the unprocessed sheet for the base layer and the unprocessed sheet for the adhesive layer is not particularly limited and may be any known method, such as a method using a punching die, a method using laser irradiation, a method using a slitting machine, or a method using a water jet.

[0142] (3.2) Filter fixing process The method for manufacturing a pellicle of this embodiment includes a filter fixing step, which results in a pellicle in which a soft frame member includes an air passage and an air filter.

[0143] In the filter fixing step, the ventilation filter is fixed to at least one base layer sheet or a part of the plurality of adhesive layer sheets so that the ventilation filter is disposed in the ventilation path. The filter fixing step is performed after the ventilation path processing step and before the lamination step.

[0144] The method for fixing the ventilation filter is not particularly limited, and examples include a method of welding or adhering the ventilation filter to the base layer sheet so that the opening formed in the base layer sheet is covered by the ventilation filter, a method of adhering the ventilation filter to the adhesive layer sheet so that the opening formed in the adhesive layer sheet is covered by the ventilation filter, and a method of holding the ventilation filter sandwiched between adjacent base layer sheets.

[0145] (3.3) Lamination process The method for manufacturing a pellicle according to this embodiment includes a lamination step, which results in a laminate.

[0146] In the lamination step, at least one base layer sheet and a plurality of adhesive layer sheets are alternately laminated in the thickness direction to form a laminate.

[0147] The number of laminated base layer sheets is the same as the number of base layers included in the flexible frame member, and the number of laminated adhesive layer sheets is the same as the number of adhesive layers included in the flexible frame member.

[0148] The lamination method for alternately laminating the base layer sheet and the adhesive layer sheet in the thickness direction is not particularly limited, and may be any known method.As the lamination method for forming a five-layer laminate, for example, the adhesive layer sheet is arranged on both main surfaces of the base layer sheet and sandwiched between a pair of rolls to form a three-layer laminate, and the adhesive layer sheet is arranged on one main surface of the base layer sheet and sandwiched between a pair of rolls to form a two-layer laminate, and the two kinds of laminates are laminated and sandwiched between a pair of rolls to form a two-layer laminate; the base layer sheet is arranged on both main surfaces of the adhesive layer sheet and sandwiched between a pair of rolls to form a three-layer laminate, and the adhesive layer sheet is arranged on both main surfaces of the obtained three-layer laminate and sandwiched between a pair of rolls to form a five-layer laminate, etc. When more than five layers are to be laminated, a two-layer laminate formed by placing a base layer sheet on one main surface of an adhesive layer sheet and sandwiching it between a pair of rolls is stacked up to the desired number of layers, and a three-layer laminate formed by placing base layer sheets on both main surfaces of an adhesive layer sheet and sandwiching it between a pair of rolls is stacked and sandwiched between a pair of rolls to form a laminate.

[0149] (3.4) Punching process The method for manufacturing a pellicle according to this embodiment includes a punching step, which results in a soft frame member.

[0150] In the punching step, the laminate is punched to form a soft frame member so as to form through-holes for exposure along the thickness direction.

[0151] The method for punching through the laminate is not particularly limited, and any known method may be used, such as a method using a punching die, a method using laser irradiation, a method using a slitting machine, or a method using a water jet.

[0152] (3.5) Surface treatment process The method for producing a pellicle of this embodiment includes a surface treatment step, which results in a pellicle in which the surface of the adhesive layer satisfies any one of the above-mentioned (A) to (C).

[0153] The surface treatment process includes at least one of a process of coating an inorganic layer on at least the inner wall surface of the adhesive layer (hereinafter referred to as the "coating process"), a process of performing plasma nitriding treatment on at least the inner wall surface of the adhesive layer (hereinafter referred to as the "plasma nitriding treatment process"), and a process of performing extreme ultraviolet irradiation treatment on at least the inner wall surface of the adhesive layer (hereinafter referred to as the "EUV irradiation treatment process").

[0154] (3.5.1) Coating process In the coating step, the inorganic layer may be coated on the inner wall surface of the adhesive layer, or the inorganic layer may be coated on the inner and outer wall surfaces of the adhesive layer. In this case, the inorganic layer may be coated on the entire inner wall surface of the pellicle frame, or the inorganic layer may be coated on the entire inner and outer wall surfaces of the pellicle frame. The method for coating at least the inner wall surface of the adhesive layer with an inorganic layer is not particularly limited, and examples thereof include vapor deposition and sputtering.

[0155] (3.5.2) Plasma nitriding process In the plasma nitriding step, the plasma nitriding may be performed on the inner wall surface of the adhesive layer, or on both the inner and outer wall surfaces of the adhesive layer. In this case, the plasma nitriding may be performed on the entire inner wall surface of the pellicle frame, or on the entire inner and outer wall surfaces of the pellicle frame.

[0156] The plasma nitriding treatment is carried out, for example, using a plasma treatment apparatus (a research and development sputtering apparatus "CFS-4EP-LL" manufactured by Shibaura Mechatronics Corporation, type: load lock type) under the following treatment conditions.

[0157] <Plasma nitriding treatment conditions> Chamber ultimate vacuum: pressure <1e -3 Pa Material gas: N2 (G1 grade) Gas flow rate: 21sccm Processing pressure: 0.5Pa · RF power: 100 W · Processing time: 1 second to 90 seconds

[0158] (3.5.3) EUV irradiation treatment process In the EUV irradiation treatment process, the inner wall surface of the adhesive layer may be subjected to EUV irradiation treatment, or the inner wall surface and the outer wall surface of the adhesive layer may be subjected to EUV irradiation treatment. At this time, the entire inner wall surface of the pellicle frame may be subjected to EUV irradiation treatment, or the entire inner wall surface and the entire outer wall surface of the pellicle frame may be subjected to EUV irradiation treatment.

[0159] The EUV irradiation treatment is performed, for example, using an EUV irradiation device (facility name: New Subar synchrotron radiation facility, beam line: "BL-9C_H-ch", operated by the Hyogo Prefectural University of Science and Technology for Advanced Industrial Science and Technology), and a quadrupole mass spectrometer: "M-200" manufactured by Canon Anelva Corporation) under the following treatment conditions.

[0160] <Treatment conditions for EUV irradiation treatment> · Irradiating light: EUV (wavelength: 13.5 nm) · Irradiation intensity: 0.3 W / cm 2 · Beam size: 2 × 0.5 mm · Irradiation time: 10 minutes

[0161] (3.6) Preparation process The method for manufacturing a pellicle according to this embodiment includes a preparation process. As a result, a rigid frame member is obtained.

[0162] In the preparation process, a rigid frame member is prepared.

[0163] The rigid frame member prepared in the preparation process may have a pellicle film stretched thereon, or may not have a pellicle film stretched thereon. Examples of the method for preparing a rigid frame member without a pellicle film stretched thereon include a method of obtaining it by transfer of a commercially available product, a method of obtaining a rigid frame member by a cutting method, etc. In the cutting method, a raw material plate, which is the material of the rigid frame member, is cut into a rigid frame member by a known method. A method for preparing a hard frame member on which a pellicle film is stretched can be, for example, a method of obtaining a commercially available product.

[0164] (3.7) Tensioning process The method for manufacturing a pellicle of this embodiment may include a stretching step when a rigid frame member without a pellicle membrane stretched thereon is prepared in the preparation step. This causes the pellicle membrane to be stretched on the rigid frame member. In other words, the pellicle membrane is supported by the rigid frame member. The tensioning step may be performed after the preparation step, and may be performed before or after the connection step.

[0165] In the stretching step, the pellicle membrane is stretched over a rigid frame member. The method for stretching the pellicle membrane over the rigid frame member is not particularly limited, and examples thereof include a method using an adhesive and a method not using an adhesive. In the adhesive method, a known adhesive is applied to a rigid frame member to form a coating film, and the pellicle film is brought into contact with the coating film and heated, thereby adhering the coating film to the pellicle film and the rigid frame member, and the pellicle frame and the rigid frame member are integrated. The method for applying the adhesive is not particularly limited, and examples thereof include a method using a dispenser. In a method that does not use adhesive, the pellicle membrane is brought into contact with the rigid frame member and pressed against each other. This causes the pellicle membrane to adhere tightly to the rigid frame member and become one with it. To facilitate chemical bonding between the rigid frame member and the pellicle membrane, pressure may be applied with a coating between the rigid frame member and the pellicle membrane.

[0166] (3.8) Connection process The method for manufacturing a pellicle according to this embodiment includes a joining step, which results in a pellicle frame in which the hard frame member and the soft frame member are integrated.

[0167] In the connecting step, the rigid frame member is connected to the flexible frame member.

[0168] The method for connecting the hard frame member to the soft frame member is not particularly limited, and involves heating an adhesive layer (hereinafter referred to as the "connecting adhesive layer") that is integrally arranged in the thickness direction of the soft frame member while the hard frame member is in contact with the adhesive layer, causing the connecting adhesive layer to adhere tightly to the hard frame member, and the hard frame member and the soft frame member to become one body. [Example]

[0169] The present disclosure will be described in more detail below with reference to examples, but the invention of the present disclosure is not limited to these examples.

[0170] [1] Example 1 [1.1] Lamination process As the adhesive for the adhesive layer, a styrene-butadiene adhesive was prepared. A polyethylene terephthalate resin sheet (thickness: 0.55 mm) was prepared as the base layer sheet. The adhesive for the adhesive layer was applied to both main surfaces of the base layer sheet using a roll coater to form coating layers for the adhesive layer on both main surfaces of the base layer sheet. In this way, one base layer sheet and two adhesive layer layers were alternately laminated in the thickness direction to form a three-layer laminate of adhesive layer / base sheet / adhesive layer. The single layer thickness of the base layer was 0.55 mm, and the single layer thickness of the adhesive layer was 0.55 mm.

[0171] [1.2] Punching process The three-layer laminate was punched using a punching die so as to form through-holes for exposure along the thickness direction, forming a 4 mm flexible frame member with a long side length of 151 mm, a width of 4 mm, and a short side length of 119 mm.

[0172] [1.3] Preparation process A rectangular silicon pellicle frame (height: 0.725 mm, length of one side (long side): 151 mm, width of one side (long side): 4.0 mm, length of one side (short side): 119 mm, width of one side (short side): 4.0 mm) was prepared as a rigid frame member.

[0173] [1.4] Connection process The hard frame member was lifted by vacuum suction, positioned so that its outer periphery coincided with that of the soft frame member, and pressed against the adhesive layer of the soft frame member with a load of 0.6 N at room temperature to integrate the hard and soft frame members. This yielded a pellicle frame. The pellicle frame had a height of 2.375 mm.

[0174] For the obtained pellicle, the apparent Young's modulus of the soft frame member, the apparent Young's modulus of the pellicle frame, and the bending rigidity of the pellicle frame were calculated using the following parameters according to the above-mentioned formulas (iv) and (v): and calculated from formula (vi). The calculation results are shown in Table 1.

[0175] <Setting parameters> · Young's modulus (Ex) of hard frame material (silicon): 185GPa Young's modulus of adhesive layer (Ex): 0.17 MPa ·Young's modulus of the base layer (Ex): 3.50GPa b (width of one side (short side) of the pellicle frame): 4 mm Thickness of rigid frame: 0.725mm - Single layer thickness of adhesive layer: (2.375mm-0.725mm) / total number of layers of soft frame material · Single layer thickness of base material layer: (2.375mm-0.725mm) / total number of layers of soft frame material Total number of layers of soft frame members: See Table 1

[0176] [2] Examples 2 to 15 Pellicles were obtained and the Young's modulus of the hard frame member and other properties were calculated in the same manner as in Example 1, except that the total number of layers, the single layer thickness of the base layer, and the single layer thickness of the adhesive layer were changed as shown in Table 1. The calculation results are shown in Table 1. In Examples 4 to 15, a three-layer laminate of layer for adhesive layer / sheet for base material / layer for adhesive layer and a two-layer laminate of layer for adhesive layer / sheet for base material were prepared, and pellicle frames were fabricated by laminating the three-layer laminate and the two-layer laminate so as to achieve the total number of layers shown in Table 1. For example, in Example 7, a two-layer laminate, a two-layer laminate, a two-layer laminate, a two-layer laminate, and a three-layer laminate were laminated in this order to fabricate a pellicle frame.

[0177] [3] Reference example 1 As shown in FIG. 8, a pellicle frame (external dimensions: 150 mm×122 mm, height H91: 3.5 mm, width W: 2.0 mm) made of anodized aluminum was prepared as the rigid frame member 91. A compounded styrene-butadiene resin adhesive was applied to the master-side end face of the hard frame member 91 using a dispenser. After placing a protective film on this, it was hot-pressed at 100°C and heated, followed by a flattening treatment to form a soft frame member 92 with a flat surface. This resulted in a pellicle frame 90. The thickness H92 of the soft frame member 92 was 0.5 mm.

[0178] For the obtained pellicle frame 90, the Young's modulus of the hard frame member was calculated in the same manner as in Example 1. The apparent Young's modulus of the pellicle frame 90 of Reference Example 1 is 693 GPa (6.93 × 10 11 The bending rigidity of the pellicle frame 90 of Reference Example 1 was 51.9 × 10 -2 Pa·m 4 It was.

[0179] The amount of distortion of the master when pellicle 9 of Reference Example 1 was attached to the master was not within the allowable range.

[0180] [Table 1]

[0181] In Table 1, "total number of layers" refers to the sum of the number of base layer layers and the number of adhesive layer layers contained in the soft frame member. "Total thickness ratio of adhesive layers" refers to the ratio of the total thickness of the adhesive layers contained in the soft frame member to the total thickness of the base layer contained in the soft frame member. "Single layer thickness of adhesive layers" refers to the thickness per layer of the adhesive layers contained in the soft frame member. "Single layer thickness of base layer" refers to the thickness per layer of the base layer contained in the soft frame member. "Young's modulus ratio of base layer" refers to the ratio of the Young's modulus of the base layer contained in the soft frame member to the Young's modulus of the adhesive layer contained in the soft frame member.

[0182] The pellicle frames of Examples 1 to 15 comprised a hard frame member and a soft frame member connected to the hard frame member. The soft frame member was formed by alternately laminating base material layers and adhesive layers in the thickness direction, with the adhesive layers disposed on both ends. The Young's modulus of the hard frame member was higher than the apparent Young's modulus of the soft frame member. The Young's modulus of the hard frame member was 185 GPa, which was greater than 25 GPa. Therefore, the bending rigidity of the flexible frame members of Examples 1 to 15 is 5.38 × 10 -2 Pa·m 4 The bending rigidity of the pellicle frame of Reference Example 1 (51.9 × 10 -2 Pa·m 4 ) was a lower value. In other words, it was found that the bending rigidity of the soft frame members of Examples 1 to 15 can reduce the amount of distortion of the master when the pellicle is attached to the master. In other words, it was found that the pellicle frame of the present disclosure can suppress distortion of the master caused by deformation of the pellicle frame. Furthermore, the Young's modulus of the rigid frame members of Examples 1 to 15 was 185 GPa. In other words, the rigid frame members of Examples 1 to 15 were sufficiently rigid. This demonstrated that the pellicle frames of Examples 1 to 15 were less likely to be distorted inwardly due to the tension of the pellicle membrane. From the above, it was found that the pellicle frames of Examples 1 to 15 can suppress distortion caused by the tension of the pellicle film and can also suppress distortion of the master caused by deformation of the pellicle frame.

[0183] The disclosure of Japanese Patent Application No. 2022-045814, filed on March 22, 2022, is incorporated herein by reference in its entirety. All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. a rigid frame member for supporting the pellicle membrane; a soft frame member connected to the hard frame member for connecting to a master having a pattern; Equipped with the soft frame member is formed by alternately laminating base material layers and adhesive layers in a thickness direction perpendicular to the surface direction of the pellicle membrane, with the adhesive layers being disposed on both ends; the Young's modulus of the hard frame member is higher than the apparent Young's modulus of the soft frame member; The Young's modulus of the hard frame member is 25 GPa or more, A pellicle frame, wherein the total number of layers of the base material layer and the adhesive layer is 5 or more.

2. The pellicle frame of claim 1 , wherein the rigid frame member is constructed from a single material.

3. 2. The pellicle frame according to claim 1, wherein the hard frame member has a Young's modulus of 90 GPa or more.

4. 2. The pellicle frame according to claim 1, wherein the ratio of the height of the rigid frame member to the height of the pellicle frame is 15% to 65%.

5. The pellicle frame according to claim 3 , wherein the thickness of each of the adhesive layers is 0.01 mm or more and 0.5 mm or less.

6. The pellicle frame according to claim 3 , wherein the total thickness of the adhesive layers included in the soft frame member is 0.2 to 4 times the total thickness of the base material layers included in the soft frame member.

7. The pellicle frame according to claim 3 , wherein the Young's modulus of the base layer is 10,000 to 9,000,000 times greater than the Young's modulus of the adhesive layer.

8. 4. The pellicle frame according to claim 3, wherein the thickness of each of the base layers is 2.5 mm or less.

9. The pellicle frame according to claim 1, wherein the surface of the adhesive layer satisfies any one of the following (A) to (C): (A) An inorganic layer is formed on at least the inner wall surface of the adhesive layer. (B) At least the inner wall surface of the adhesive layer satisfies the following formula (1): (C) At least the inner wall surface of the adhesive layer satisfies the following formula (2): Formula (1): ([CNO － ２ｓ / [CNO － ５０ｓ ) ≥ 2.00 (In the formula (1), [CNO － ２ｓ ] is a time-of-flight secondary ion mass spectrometry method for a first deep portion having a first depth from the surface of the adhesive layer, using an ion source of Bi ３ ＋＋ ions and a primary ion gun having an irradiation area of ​​100 μm×100 μm. the first depth is formed by irradiating a 600 μm square area of ​​the surface with a sputter ion gun, which is an argon gas cluster ion beam having a beam voltage of 20 kV and a beam current of 20 nA, for a cumulative period of 2 seconds; [CNO － ５０ｓ ] is a CNO obtained by analyzing the second deep portion having the second depth by time-of-flight secondary ion mass spectrometry. － indicates the normalized intensity of The second depth is formed by irradiating the area with the sputter ion gun for a cumulative period of 50 seconds. Equation (2): ([C ３ － ２ｓ ] / [C ３ － ５０ｓ ]) ≥ 1.10 (In the formula (2), [C ３ － ２ｓ ] is the C obtained by analyzing the first deep portion by time-of-flight secondary ion mass spectrometry. ３ － indicates the normalized intensity of [C ３ － ５０ｓ ] is the C obtained by analyzing the second deep portion by time-of-flight secondary ion mass spectrometry. ３ － Normalized intensity of

10. The pellicle frame according to claim 1 , wherein the flexible frame member includes an air passage passing through the flexible frame member, or the air passage and an air filter disposed in the air passage.

11. A pellicle frame according to any one of claims 1 to 10; a pellicle membrane supported by the rigid frame member; A pellicle comprising:

12. a master having a pattern; The pellicle according to claim 11, which is attached to a surface of the master on which a pattern is formed. Including, exposed master plate.

13. a light source that emits exposure light; The exposure master according to claim 12; an optical system that guides the exposure light emitted from the light source to the exposure master; and an exposure apparatus, wherein the exposure master is positioned so that exposure light emitted from the light source is transmitted through the pellicle film and irradiated onto the master; 14. A method for manufacturing a pellicle according to claim 11, comprising: providing the rigid frame member; a lamination step of alternately laminating at least one base layer sheet and a plurality of adhesive layer layers in the thickness direction to form a laminate; a punching step of punching the laminate to form an exposure through-hole along the thickness direction, thereby forming the soft frame member; a connecting step of connecting the rigid frame member to the flexible frame member; A method for manufacturing a pellicle, comprising:

15. 15. A method for manufacturing a pellicle as described in claim 14, comprising at least one of the following steps: coating an inorganic layer on at least the inner wall surface of the adhesive layer; subjecting at least the inner wall surface of the adhesive layer to plasma nitriding treatment; and subjecting at least the inner wall surface of the adhesive layer to extreme ultraviolet irradiation treatment.

16. the flexible frame member includes an air passage passing through the flexible frame member; the layer for adhesive layer is a sheet for adhesive layer, an air passage processing step of processing at least one base layer raw sheet and a plurality of adhesive layer raw sheets so as to form the air passage, thereby forming the at least one base layer sheet and the plurality of adhesive layer sheets; The method for manufacturing a pellicle according to claim 14 , wherein the air passage processing step is performed before the stacking step.

17. the flexible frame member includes the air passage and an air filter disposed in the air passage; a filter fixing step of arranging the ventilation filter in a part of the at least one base layer sheet or the plurality of adhesive layer sheets so that the ventilation filter is disposed in the air passage; The method for manufacturing a pellicle according to claim 16 , wherein the filter fixing step is performed after the air passage processing step and before the laminating step.

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