JP2012053302A - Frame for pellicle, and pellicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a frame for a large pellicle showing little deformation after a heating test.SOLUTION: A frame (2) for a pellicle having an opening (4) being rectangular in a plan view, comprises a plurality of components (41a, 41b, 41c, and 41d) forming the edge of the opening (4) with the ends joined together. Each end of the components (41a and 41b) is equipped with at least one projection (P) projecting toward the component (41c or 41d), and each end of the components (41c and 41d) is equipped with a depression (C) into which the projection (P) is fitted. By fitting the projections (P) into the depressions (C), the ends of the components (41a and 41b) and the ends of the components (41c and 41d) are joined together.

Description

  The present invention is used when manufacturing semiconductor devices such as IC (Integrated Circuit), LSI (Large Scale Integration), TFT LCD (Thin Film Transistor, Liquid Crystal Display), etc. The present invention relates to a large pellicle frame used to prevent foreign matter from adhering to a photomax and a reticle used in the lithography process.

  2. Description of the Related Art Conventionally, in manufacturing semiconductor circuit patterns and the like, dust prevention means called a pellicle is disposed on both sides of a photomask or reticle to prevent foreign matter from adhering to the photomask or reticle.

  As a general structure of a pellicle, a transparent thin film such as a polymer or glass is attached to one edge surface of a metal, ceramic, or polymer frame, and the other edge surface is attached to a mask. What provided the adhesive layer (adhesive material) is mentioned. For example, a pellicle is formed from a transparent polymer film such as nitrocellulose or a cellulose derivative having a thickness of 10 μm or less on one edge surface of a frame of about several millimeters thick having a shape matched to the shape of a photomask or a reticle. A pellicle film is spread and bonded, and is attached to the other edge surface of the frame body on the surface of a photomask or reticle via an adhesive material.

  When foreign matter adheres to the surface of a photomask or reticle, the foreign matter forms an image on the photoresist formed on the semiconductor wafer and causes a circuit pattern defect. However, the pellicle must be formed on at least the pattern surface of the photomask or reticle. When the is placed, the foreign substance adhering to the surface of the pellicle is out of focus, so that it does not form an image on the photoresist formed on the semiconductor wafer and the circuit pattern will not be defective.

  In recent years, with the widespread use of various types of multimedia, there is a demand for a large pellicle applicable to a large photomask used in the photolithography process of a large color TFT LCD capable of high-quality and high-definition display. .

  For example, Patent Document 1 proposes a large pellicle applicable to a large photomask. Patent Document 2 also proposes a frame body using a frame and a reinforcing material having a larger elastic coefficient than the frame body in order to cope with bending and distortion of the large pellicle frame body. Further, Patent Document 3 discloses a pellicle frame used for ultraviolet light exposure of 200 nm or less used in exposure that requires high resolution, and does not affect the accuracy of mask flatness, It has also been proposed to use a frame obtained by joining two or more types of materials having different elastic moduli in the thickness direction of the frame.

JP 2001-109135 A JP 2006-284927 A JP 2009-063740 A

  By the way, the pellicle frame is often cut out by one punching from one sheet-like base material. This is based on the viewpoint of ensuring the flatness of the pellicle. Therefore, although there are many base materials having flatness, the larger the size of the pellicle frame, the more difficult it is to obtain the accuracy of flatness of the frame, and it also takes time and effort in the manufacturing process. This is a cause of reduction and high cost of the frame.

  Also, if the size is increased, the frame itself may be bent or distorted due to various factors such as the weight of the frame itself, the tension of the pellicle film, and the stress caused by the temperature change. A frame body produced by punching from a sheet-like base material is generally used. Such bending or distortion occurs inwardly due to the tension of the film on the frame after the pellicle film is attached, but the bending and distortion are made as small as possible due to the demand of the photomask manufacturer to secure an exposure area. There is a need to. Therefore, there is a method of increasing the rigidity of the pellicle frame by increasing the cross-sectional area of the frame, but this is not preferable in view of the effective exposure area and the like.

  For the reasons described above, from the viewpoint of cost, I would like to use a frame divided by a large pellicle (hereinafter referred to as a divided frame), but in the divided frame, there is a possibility that the frame will be bent or distorted, In addition, the present situation is that the rigidity does not satisfy practical characteristics and is not put into practical use as a product.

  Patent literature 2 etc. are introduced as literature using a divided frame, and according to the literature, in order to ensure rigidity, an adhesive etc. is used using a member higher in rigidity than a frame in a joint part. There is a description of using a special method such as friction stir welding. However, when an adhesive is used, special processing is required for the joint portion such as an adhesive reservoir, or outgassing from the adhesive may occur during exposure. In addition, special welding techniques are required for friction stir welding and the like.

    The present invention has been made in view of such circumstances, and in configuring a large pellicle frame body using a member (frame body having a joint portion), a member having higher rigidity than the frame body at the joint portion, An object of the present invention is to maintain rigidity and dimensional stability with no practical problems as a pellicle frame without using an adhesive or the like, and to improve the yield.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that a pellicle frame having a specific structure at the joint can solve the above-mentioned problems, and complete the present invention. It came.

  That is, the pellicle frame body according to the present invention is a pellicle frame body having a rectangular opening in a plan view, and has a member that forms the periphery of the opening by joining the ends together. At least one convex portion that protrudes toward the other member to be joined is provided at the end portion of the one member to be joined, and a concave portion for fitting the convex portion is provided at the end portion of the other member. Then, the end of one member is joined to the end of the other member by fitting the convex portion into the concave portion. In the present invention, “fitting” means that the convex portion is formed slightly larger than the concave portion, the concave portion is formed slightly smaller than the convex portion, or the convex portion and the concave portion are formed in the same size. When the convex portion is inserted into the concave portion and joined, the convex portion is compressed and deformed inward by the inner peripheral surface of the concave portion, or even if there is no compression deformation, the convex portion bites into the concave portion without a gap. It means a state that can be matched.

  By adopting such a configuration, it becomes possible to make the bending rigidity and shear rigidity at a level having no practical problem without using a reinforcing material, an adhesive, a special welding technique, or the like that is higher in rigidity than the frame. In addition, the stress concentration at the joint is alleviated due to inward bending due to the film tension after the film is attached to such a frame, so that gaps and backlash are less likely to occur at the joint. This is preferable because the shape is stable and the generation of dust due to looseness is small. For this reason, even when the inspection is performed with the large pellicle fixed to the handling jig, the pellicle hardly falls from the handling jig even when the position is changed in various directions.

  Further, by using a member (a frame body having a joint portion) rather than cutting out from a single base material, the number of cutting processes is reduced, and the residual stress applied to the frame body during processing is reduced. In addition, considering the anisotropy of the material, the divided frame body can use members having the same directionality, so that the anisotropy of the entire frame body is reduced. Since the residual stress and anisotropy are thus reduced, the release due to stress strain or the like during the heating process in the pellicle manufacturing process is reduced, and the dimension of the pellicle is stabilized, which is preferable. For this reason, it is not necessary to perform heat treatment or the like in advance in order to release the residual stress, and there is a manufacturing merit that the number of processes is reduced. Further, since the stress strain tends to open in the course of time, the divided frame body having a small residual stress is preferable because the dimensions are stable even when stored for a long period of time.

  Furthermore, by forming the frame body with a plurality of members, it becomes possible to cut out portions with good flatness of the base material, and the flatness of the frame body after joining is also improved. It is also possible to produce a large frame from a small base material, which has the advantage of cost reduction.

  As described above, based on the viewpoint of ensuring the flatness of the pellicle, the pellicle frame body is often cut out from a single sheet-like base material by punching. The present invention has been made against such technical common sense and has the excellent effects as described above.

  In the pellicle frame, it is preferable from the viewpoint of dimensional stability that the maximum lateral dimension (t) on the base side of the convex portion is shorter than the maximum lateral dimension (v) on the tip side. Further, the maximum lateral dimension (t) on the base side of the convex part is set to a length of 5% to 80% with respect to the width of the member on which the convex part is provided, and the maximum lateral dimension (v on the tip side of the convex part) ) Is preferably set to a length of 10% to 90% with respect to the width of the member provided with the convex portion. Here, although the numerical value may be changed depending on the positioning of the member in the width direction, the measurement position in the width direction is not particularly limited, and it is sufficient that the above condition is satisfied by any measurement position in the width direction. In the case of the width, the above numerical value range may be entered in either the width on the pellicle film surface side or the width on the mask adhesive side.

  In the pellicle frame, the maximum lateral dimension (t) on the base side of the convex portion is set to a length of 5% to 80% with respect to the thickness of the member on which the convex portion is provided. It is preferable to set the maximum lateral dimension (v) on the distal end side to a length of 10% to 90% with respect to the thickness of the member provided with the convex portion. Here, it is assumed that the numerical value may change depending on the positioning of the member in the thickness direction, but there is no particular limitation on the measurement position in the thickness direction, and the above condition may be satisfied by any measurement position in the thickness direction. That's fine.

  The maximum lateral dimension (t) on the base side of the convex part is the maximum dimension of the base part where the convex part is connected to the joint end surface of the member (for example, two points as shown in FIG. 6A in plan view). The maximum lateral dimension (v) on the tip side of the convex part means the tip side part of the convex part in the direction substantially perpendicular to the longitudinal direction of the member (the part excluding the root part) ) Means the maximum dimension.

  Further, in the pellicle frame body, there are one or more joint portions (fitting portions). However, when there is one joint portion, when cutting from a single base material, Even if it does not require dimensional accuracy, it can be adjusted at the joint, and a single member can be plastically deformed to form a frame, which saves the base material. Furthermore, it is preferable to have two or more joints because the flatness can be easily adjusted. By having two or more places in this way, it is possible to increase the accuracy of processing of each part constituting the pellicle frame body, thereby making it possible to obtain flatness accuracy more easily than a single base material. Accuracy will increase.

  Further, in the pellicle frame, the convex portion has an excessive outer peripheral portion that is compressed and deformed inward by the inner peripheral surface of the concave portion when fitted with the concave portion, or the concave portion is fitted with the convex portion. It sometimes has an excess outer peripheral portion that is compressed and deformed inward by the outer peripheral surface of the convex portion. By adopting such a configuration, by fitting the end portions of the members from above and below, the excess outer peripheral portion is crushed and bulged outward, so that each joining portion is tightly and firmly joined without a gap. Therefore, bending rigidity, shear rigidity, and the like are increased without using a reinforcing material having higher rigidity than the frame. Further, since there is an extra outer peripheral portion, no adhesive is required, and there is no worry of outgassing during exposure. It is preferable that the dimension of the excess outer peripheral part is at least 0.001 mm or more (for example, 0.005 mm or more and 0.1 mm or less). In addition, an adhesive etc. can also be used when a surplus outer peripheral part is about 0 mm.

  The pellicle according to the present invention includes the pellicle frame and a pellicle film that is stretched and supported so as to cover the opening of the pellicle frame.

  According to the present invention, there is provided a pellicle frame body which maintains rigidity without any practical problem as a pellicle frame body without using a member or adhesive having higher rigidity than the frame body and has excellent dimensional stability. be able to.

1 is a perspective view of a pellicle according to an embodiment of the present invention. It is a top view of the frame for pellicles concerning the embodiment of the present invention. It is an expansion perspective view of the corner | angular part of the frame for pellicles concerning embodiment of this invention. It is a top view of the frame for pellicles concerning other embodiments of the present invention. It is a top view of the frame for pellicles concerning other embodiments of the present invention. FIG. 5 is an explanatory diagram for explaining a configuration of a joint portion of the pellicle frame shown in FIG. 3 or FIG. 4. (A) is an enlarged view of the junction part of the frame for pellicles shown in FIG. 5, (b) is an enlarged view which shows the modification. (A), (b), (c) is an enlarged view of a modification of the joint part of the pellicle frame according to each embodiment of the present invention. It is an enlarged view of the junction part in a comparative example. It is an enlarged view of the junction part in a reference example. It is an enlarged view of the junction part in a reference example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments (embodiments) for carrying out the present invention will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

  First, a pellicle according to an embodiment of the present invention will be described. FIG. 1 is a perspective view showing a large pellicle 1 according to an embodiment of the present invention. The large pellicle 1 includes a large pellicle frame 2 and a large pellicle film 3 bonded to the upper edge surface 2 e of the large pellicle frame 2. Although not shown, the large pellicle 1 includes an adhesive layer applied to the lower edge surface of the large pellicle frame 2, a protective film that adheres to the adhesive layer and protects the adhesive layer, Is further provided.

The large pellicle frame 2 is made of, for example, aluminum, aluminum alloys (5000 series, 6000 series, 7000 series, etc.), iron and iron alloys, ceramics (SiC, AlN, Al2O3, etc.), a composite material of ceramics and metal (Al -SiC, Al-AlN, Al- Al 2 O 3 , etc.), carbon steel, tool steel, stainless steel series, made of a polymer or the like, and has a substantially rectangular shape in plan view.

As the surface treatment of the frame, alumite treatment, painting, paint coating, plating treatment, low melting point glass frit treatment, CVD treatment, PVD treatment by sputtering, etc. can be employed. The large pellicle frame 2 is composed of a pair of long sides 2a and 2b and a pair of short sides 2c and 2d shorter than the long sides 2a and 2b, and has a rectangular opening 4. ing. Area of the opening 4 is preferably is a 1000 cm ² or more, more preferably is a 3000 cm ² or more, more preferably it is between 5000 cm ² or more. The opening area of the opening 4 is preferably 35000 cm ² or less.

  The pair of long sides 2a and 2b is made of a columnar member having a width of 9.0 mm, for example, and the length thereof is, for example, 800 mm. The pair of short sides 2c, 2d is a columnar member having a width of, for example, 7.0 mm, and the length thereof is, for example, 480 mm. That is, the width of the short sides 2c and 2d in plan view (top view) is narrower than the width of the long sides 2a and 2b. The curvature of the corner 5 of the large pellicle frame 2 is, for example, R = 2 mm. Further, a groove portion 7 is provided along the longitudinal direction (side direction) on the side surfaces 6 of the short sides 2c and 2d of the large pellicle frame 2.

  The large pellicle film 3 is made of a transparent polymer film such as nitrocellulose, a cellulose derivative, a fluorine polymer, or a cycloolefin polymer, and the thickness thereof is preferably, for example, 0.1 μm or more and 10 μm or less. The large pellicle film 3 is spread on the upper edge surface 2 e so as to cover the opening 4 of the large pellicle frame 2, and is attached to and supported by the pellicle frame 2.

  Examples of the adhesive that bonds the large pellicle film 3 to the upper edge surface 2e of the large pellicle frame 2 include fluorine such as an acrylic resin adhesive, an epoxy resin adhesive, a silicone resin adhesive, or a fluorine-containing silicone adhesive. System polymers can be used. In addition, as an adhesive material to support adhesion, styrene ethylene butylene styrene, styrene ethylene propylene styrene, or olefin-based hot-melt adhesive material, silicone adhesive material, acrylic adhesive material, or foam-based adhesive material Tape can be used. The thickness of the adhesive material layer is preferably set so that the total thickness of the large pellicle frame 2 and the adhesive material thickness does not exceed the prescribed distance between the large pellicle film 3 and the photomask. , 0.01 mm or more and 10 mm or less is preferable.

  In addition, if a space exists inside the adhesive layer when the large pellicle film 3 is attached to the photomask, there is a possibility that foreign matter may stay in the space. Therefore, when applying an adhesive to the lower edge surface of the large pellicle frame 2, considering that the pressure-sensitive adhesive layer is crushed and spread by the pressure applied when the large pellicle 1 is attached to the photomask, It is preferable to apply to the inside of the opening 4 of the large pellicle frame 2 so that the adhesive does not protrude into the opening 4 during pressurization. Specifically, it is preferable to apply so that the width of the space inside the adhesive layer is within 0.35 times the application width of the adhesive layer. The application width of the pressure-sensitive adhesive layer is preferably 0.3 to 0.6 times the width of each side 2a to 2d of the large pellicle frame 2, and is applied to each side 2a to 2d of the large pellicle frame 2. It is preferable to apply along. As a protective film for protecting the adhesive material, a film made of polyethylene terephthalate resin or polyethylene resin can be used. Further, a release agent such as a silicone release agent or a fluorine release agent may be applied to the surface of the protective film according to the adhesive strength of the adhesive material. As for the thickness of a protective film, 0.01 mm or more and 1 mm or less are preferable, for example.

  Next, a pellicle frame body according to an embodiment of the present invention will be described.

  First, a large pellicle frame 2 according to an embodiment of the present invention will be described with reference to FIGS. 2 (8-divided structure) is a view (plan view) of a large pellicle frame 2 used in a large pellicle as shown in FIG. 1 as viewed from above, and FIG. 3 shows the vicinity of the corner of FIG. It is an enlarged perspective view shown. In FIG. 1, the description of the joint portion is omitted.

  In the large pellicle frame 2, the frame portion constituting the peripheral portion of the opening 4 includes divided frame members 21a and 21b, which are long-side members constituting the pair of long sides 2a and 2b, respectively, and the divided frame member 21a. , 21 b, 21 b, 21 f, 21 f, 21 b, 21 b, 21 b, 21 b, 21 b, 21 b, 21 b, 21 b, 21 b 21g and the divided frame bodies 21c, 21d, which are short-side members that respectively constitute a pair of short sides 2c, 2d by bridging the open ends of the divided frame bodies 21e, 21h, 21f, 21g through a joint portion. And is formed from. That is, the large pellicle frame body 2 has eight joint portions along the axial direction of the frame portion constituting the peripheral portion of the opening 4. Thus, when providing a junction part near a corner | angular part, you may provide perpendicularly or diagonally with respect to an axial direction besides an axial direction.

  In FIG. 2, the large pellicle frame body 2 has a divided frame body 21a, a divided frame body 21d, a divided frame body 21f in a clockwise direction with the divided frame body 21a as a base point and the opening axis of the opening 4 as a reference. The divided frame body 21b, the divided frame body 21g, the divided frame body 21c, the divided frame body 21h, and the divided frame body 21a are connected in this order. Here, the number of joint locations may be one or more, but is preferably 2 to 30 locations, more preferably 2 to 20 locations, and even more preferably 3 to 15 locations.

  In the large pellicle frame 2, the long side 2a and the long side 2b are formed to have the same length, and the short side 2c and the short side 2d are formed to have the same length. Moreover, the shape of the division | segmentation frame 21a and the division | segmentation frame 21b is substantially the same, the shape of the division | segmentation frame 21c and the division | segmentation frame 21d is substantially the same, and also the division | segmentation which forms the corner | angular part 5 respectively. The shapes of the frames 21e, 21h, 21f, and 21g are also substantially the same. Specifically, in FIG. 2, the length of the divided frame bodies 21a and 21b is, for example, 700 mm, and the length of the divided frame bodies 21c and 21d is, for example, 380 mm.

  The width of each side 2a to 2d of the pellicle frame 2 is preferably as thin as possible from the viewpoint of securing the exposure area. However, if the width is too small, the pellicle frame body is stretched by the tension of the pellicle film 3 when the pellicle film 3 is stretched. There is a possibility that a problem that 2 is bent occurs. Since it becomes the thickness of the width which considered rigidity with respect to the length of each side, it can be set as about 3 mm-25 mm. In addition, the thinner the pellicle frame 2 is, the lighter and easier to handle the large pellicle 1 becomes. However, if the pellicle frame 2 is too thin, the pellicle frame 2 is bent by the tension of the pellicle film 3 when the pellicle film 3 is stretched. There is a risk that the problem will occur. The thickness of the pellicle frame body 2 is preferably about 3.5 mm to 12 mm from the balance between the two sides 2a to 2d.

  FIG. 4 shows an example (another embodiment) of a pellicle frame configured by using a divided frame different from that in FIG. FIG. 4 shows an example of a four-divided frame body. In the large pellicle frame body 2, the frame portion constituting the peripheral portion of the opening 4 is a divided frame that is a member constituting each of the pair of long sides 4a and 4b. The body 41a and 41b and the division | segmentation frame bodies 41c and 41d which are the members which respectively comprise a pair of short sides 4c and 4d are formed. That is, the large pellicle frame body 2 has four joint portions along the axial direction of the frame portion constituting the peripheral edge portion of the opening 4. In the large pellicle frame 2, the long sides 4 a and the long sides 4 b are formed to have the same length, and the short sides 4 c and the short sides 4 d are formed to have the same length.

  FIG. 5 also shows an example (another embodiment) of a pellicle frame configured by using a different divided frame from FIG. FIG. 5 shows an example of an eight-divided frame body. In the large pellicle frame body 2, the frame portion that forms the peripheral portion of the opening 4 is a divided frame that is a member that forms a pair of long sides 5a and 5b. The body 51a, 51a ', 51b, 51b' and divided frame bodies 51c, 51c ', 51d, 51d' which are members constituting the pair of short sides 5c, 5d, respectively. That is, the large pellicle frame body 2 has eight joint portions along the axial direction of the frame portion constituting the peripheral portion of the opening 4. In the large pellicle frame 2, the long sides 5a and the long sides 5b are formed to have the same length, and the short sides 5c and the short sides 5d are formed to have the same length.

  In the pellicle frame according to the embodiment shown in FIGS. 2 to 4, the shape in which the joint is provided in the vicinity of the corner is illustrated as an example. However, as illustrated in FIG. 5, the pellicle frame is provided at each necessary position on each side. May be. Although it is preferable to provide it at each necessary location on each side because thermal expansion due to heating or the like in the pellicle manufacturing process can be mitigated at the joint, it is more preferable to provide the joint near the corner.

  In the pellicle frame according to the embodiment shown in FIG. 2, two long-side members constituting a pair of opposed long sides, and two short-side members constituting a pair of opposed short sides, The corner member constituting the four corners is employed, and the ends of the long side member and the short side member are respectively joined to the corner member, and for the long side via the corner member. It is good also as a frame body of the planar view rectangle shape by connecting a member and the member for short sides. Further, in the pellicle frame body according to the embodiment shown in FIG. 3 or FIG. 4, two long side members constituting a pair of opposed long sides and two pieces constituting a pair of opposed short sides. The short side member may be employed, and the end portions of the long side member and the short side member may be joined to each other to form a rectangular frame in plan view. If it does in this way, a joined part can be arranged near the corner of a rectangular frame in plan view, and when the joined part is provided in the vicinity of the corner, one side is cut out, so the productivity increases. At the same time, it is possible to maintain the same rigidity as a cut piece from a single base material by joining the vicinity of the corner with high rigidity. It is preferable because it can be maintained.

  FIG. 6 is an enlarged view of the joint portion of the pellicle frame according to the embodiment shown in FIGS. 3 and 4. Moreover, Fig.7 (a) is an enlarged view of the junction part of the frame body for pellicles concerning embodiment shown in FIG. 5, FIG.7 (b) is the modification. FIG. 8 is an enlarged view of a modified example of the joint portion of the pellicle frame according to each embodiment. In FIG. 8, any of (a), (b), and (c) can be taken. Further, these are merely examples, and do not limit the shape of the joint.

  As shown in FIG. 6 (a), in the pellicle frame according to each embodiment of the present invention, the other member (divided frame) joined to the end of one member (divided frame) to be joined. At least one convex portion P projecting toward the body is provided, and a concave portion C into which the convex portion P is fitted is provided at an end portion of the other member (divided frame body). Then, by fitting the convex portion P into the concave portion C, the end portion of one member (divided frame body) is joined to the end portion of the other member (divided frame body).

  The present invention is a frame for a large pellicle characterized in that the joint portion is a fitting portion. By adopting such a shape, there is no practical problem in bending rigidity or shear rigidity of the joint portion. When the pellicle film is attached, the frame will bend inward, but the stress concentration will be relaxed in this case as well, so it will be difficult for gaps and backlash at the joints to occur, and use a divided frame Even so, it is preferable because the dimensions are stable.

  In the pellicle frame according to the present embodiment, as shown in FIG. 6, the maximum lateral dimension t of the base side portion of the convex portion P provided on the end portion (joint end surface s) of one member is expressed as follows. It is preferably set to be shorter than the maximum lateral dimension v of the front end side portion of the convex portion P (the portion that fits into the concave portion C formed in the joint portion u of the other member). Such a structure may be in the width direction of the member (divided frame) or in the thickness direction. If it is in the width direction, it is more preferable to prevent the frame from being bent to the inner side after the film is stretched. If it is in the thickness direction, even if the inner wall or the outer wall is raised, the mask adhesion The width direction in which the material or the film adhesive is applied is preferable because it becomes flat.

  The maximum lateral dimension t on the base side of the convex portion P is preferably set to a length of 5% to 80% with respect to the width of the member on which the convex portion P is provided. Moreover, it is preferable that the maximum lateral dimension v on the tip side of the convex portion P is set to a length of 10% to 90% with respect to the width of the member on which the convex portion P is provided. Furthermore, the maximum lateral dimension t on the base side of the convex portion P is more preferably set to a length of 7% to 60% with respect to the width of the member, and is set to a length of 10% to 40%. Is more preferable. The maximum lateral dimension v on the tip side of the convex portion P is more preferably set to a length of 15% to 75% with respect to the width of the member, and is set to a length of 20% to 50%. Is more preferable. In addition, each said maximum horizontal dimension has shown the sum total of each maximum joining distance, when there exist with respect to the width | variety of a junction part.

  When the maximum lateral dimension t on the base side of the convex portion P is smaller than 5% with respect to the width of the member, the catch at the joint (fitting portion) is weak, and the left and right tensile strength may be reduced, When the pellicle film is attached to the inside of the frame body, it is not preferable because concentrated stress is applied to the joining end surface joining portion, and gaps and backlash may occur at the joining end surface portion. Further, when the maximum lateral dimension t on the base side of the convex portion P is larger than 80% with respect to the width of the member, the convex portion P is crushed and bulged outward when fitted from above and below, so that the frame The inner and outer surfaces of the body may rise, which is not preferable. Furthermore, when the maximum lateral dimension v on the tip side of the convex portion P is smaller than 10% with respect to the width of the member, the catching portion (fitting portion) is weakly caught and the left and right tensile strength may be lowered. In addition, when the pellicle film is attached to the inside of the frame body, concentrated stress is applied to the joining end surface joining portion, and there is a possibility that a gap or play may occur at the joining end surface portion. Further, when the maximum lateral dimension v on the front end side of the convex portion P is larger than 90% with respect to the width of the member, the convex portion P is crushed and bulges outward when fitted from above and below. The inner and outer surfaces of the body may rise, which is not preferable.

  Moreover, it is preferable that the maximum horizontal dimension t on the base side of the convex portion P is set to a length of 5% to 80% with respect to the thickness of the member (divided frame body) on which the convex portion P is provided. Moreover, it is preferable that the maximum lateral dimension v on the tip side of the convex portion P is set to a length of 10% to 90% with respect to the thickness of the member (divided frame body) on which the convex portion P is provided. Furthermore, the maximum lateral dimension t on the base side of the convex portion P is more preferably set to a length of 7% to 60% with respect to the thickness of the member, and is set to a length of 10% to 40%. Is more preferable. The maximum lateral dimension v on the tip side of the convex portion P is more preferably set to a length of 15% to 75% with respect to the thickness of the member, and is set to a length of 20% to 50%. Is more preferable. In addition, each said maximum horizontal dimension has shown the sum total of each maximum joining distance, when there exist two or more with respect to the thickness of a junction part.

  When the maximum lateral dimension t on the base side of the convex portion P is smaller than 5% with respect to the thickness of the member, there is a possibility that the joint portion is easily loosened when the pellicle membrane is bent inward due to the film tension. Therefore, it is not preferable. Further, when the maximum lateral dimension t on the root side of the convex portion P is larger than 80% with respect to the thickness of the member, the convex portion P is crushed and bulges outward when fitting from the left and right. The upper and lower side surfaces of the frame body may rise, which is not preferable. Further, when the maximum lateral dimension v on the tip side of the convex portion P is smaller than 10% with respect to the thickness of the member, there is a possibility that the joint portion is likely to be loosened when the pellicle membrane is bent inward due to the film tension. This is not preferable. Further, when the maximum lateral dimension v on the tip side of the convex portion P is larger than 90% with respect to the thickness of the member, the convex portion P is crushed and bulges outward when fitting from the left and right. The upper and lower side surfaces of the frame body may rise, which is not preferable. When the upper and lower side surfaces rise, it is not preferable because the flatness of the frame body is deteriorated and the attaching accuracy may be deteriorated.

  As the shape of the convex portion P, a round pierced shape, a wedge shape, a square shape, a triangular shape, and other various shapes (such as shapes used in a jigsaw puzzle) can be adopted. The number of the convex portions P may be one to a plurality with respect to the width and thickness of the member (divided frame body). In the case of one piece, stress is concentrated on the starting end portion from the joint end face with respect to the inward bending of the frame body, so there is a possibility that a gap or a gap is left on the joint end face. For this reason, the end surface of the joint portion may be joined by another joining method in an auxiliary manner with caulking, an adhesive, or the like. Since the width and thickness of the pellicle frame are not so large, one to four is more preferable, and one to two is more preferable.

  In addition, when the convex part P of special shape as shown in FIG.8 (c) is employ | adopted, the largest horizontal dimension t of the root side part of the convex part P is set to the largest horizontal dimension of the front end side part of the convex part P. FIG. It can also be set to the same length as v.

  Further, in the pellicle frame according to the present embodiment, the protrusion P provided at the end of one member to be joined is formed at the end of the other member to be joined as shown in FIG. It has an excess outer peripheral portion (hereinafter referred to as “joining gap”) G that is compressed and deformed inward by the inner peripheral surface of the concave portion C when fitted with the provided concave portion C. The dimension of the bonding gap G is preferably 0.1 mm or less. When joining, fitting is performed from the top and bottom or from the left and right. Since this joining gap G is crushed and swelled outward when fitting, close joining is possible. If the size of the joint gap G is larger than 0.1 mm, the portion to be crushed becomes large and the frame body rises in the vertical and horizontal directions, which is not preferable. By having this bonding gap G, an adhesive or the like is not required, and it is possible to perform strong bonding simply by fitting. The dimension of the bonding gap G is preferably 0.005 mm to 0.06 mm, and more preferably 0.01 mm to 0.04 mm.

  The present invention is not limited to the embodiment described above. For example, in the above embodiment, the shapes of the divided frame bodies are aligned to some extent, but the shapes of the divided frame bodies may be different from each other.

  Next, the present embodiment will be described more specifically with reference to examples and comparative examples. However, the present embodiment is not limited to the following examples as long as the gist thereof is not exceeded.

[Example 1]
The material of the large pellicle frame (the material of all the divided frames) was an aluminum alloy, the thickness was 4.0 mm, and the long sides were 6.0 mm wide and 430 mm long. The short side had a width of 6.0 mm and a length of 300 mm, and was provided with a groove over the entire length of the short side. The groove depth was 2 mm and the groove height was 1.5 mm. . Further, the curvature of the corner portion was R = 2 mm. Otherwise, a large pellicle frame was formed as shown in FIG. The length of the divided frame bodies 21a and 21b was 370 mm, and the length of the divided frame bodies 21c and 21d was 240 mm. The joining part was made into the shape by which one round convex part was provided in the edge part of one member like FIG. The maximum horizontal dimension on the root side of the convex part is set to a length of 1.6 mm, the maximum horizontal dimension on the tip side of the convex part is set to 3.0 mm, the dimension of the joint gap is set to 0.03 mm, The adhesive was fitted from above and below without using an adhesive. As a result of visual inspection, there was no problem in appearance.

(Dimensional stability measurement)
After measuring the external dimensions of the above frame body and performing a heat treatment at 140 ° C. for 10 minutes on a hot plate, the external dimensions of the central part of the long side were measured to determine the amount of deformation. External dimensions were measured with Mitutoyo FAL-1600 series. The results are shown in Table 1.

(Joint strength test)
Next, a bonding strength test was performed. A sample of a 100 mm rod-shaped member including the same joint shape portion as described above was produced. The joining portion was at a position of 50 mm, which is half of a 100 mm rod-shaped member. Chucking is performed 10mm from the joint with the width direction facing the upper surface (chucking is in the range of 10mm to 30mm from the joint), and the opposite side of chucking is applied to a location 10mm from the joint It was measured. The measuring device was an Imada digital force gauge. The results are shown in Table 1.

  Next, a styrene ethylene butylene styrene-based hot melt adhesive having a thickness of 1.4 mm was applied as an adhesive along each side of the pellicle frame to the large pellicle frame. Separately, a pellicle film of cellulose ester was formed on a substrate by spin coating, and the film was adhered to a temporary frame and then peeled off from the substrate. This temporary frame was made of aluminum. Thereafter, an acrylic film adhesive is applied to the opposite side of the large pellicle frame coated with the hot melt pressure-sensitive adhesive to which the hot-melt pressure-sensitive adhesive is not coated, and the pellicle film of the temporary frame is adhered. It hardened | cured, the excess film | membrane was cut | disconnected, the pellicle was produced, and the external appearance was test | inspected visually, and it confirmed that there was no problem. Since the frame body was bent inward after cutting, the joint surface of the joint portion was visually confirmed after the shape was stabilized. The results are shown in Table 1.

[Example 2]
The width of the long side was set to 9.0 mm, the length was set to 800 mm, the width of the short side was set to 7.0 mm, the length was set to 480 mm, and the curvature of the corner portion was set to R = 0 mm. The length of the other grooves and the thickness of the frame were the same as in Example 1. In this example, the divided frames as shown in FIG. 4 were used, 41c and 41d were 480 mm, and 41a and 41b were 790 mm. As shown in FIG. 7A, the joint portion has a shape in which two round convex portions are provided at the end of one member. The maximum lateral dimension on the root side of the convex part is set to a length of 1.5 mm, the maximum lateral dimension on the tip side of the convex part is set to 2.0 mm, and the dimension of the joint gap is set to 0.02 mm, The adhesive was fitted from above and below without using an adhesive. As a result of visual inspection, there was no problem in appearance. Thereafter, a pellicle was prepared in the same manner as in Example 1 except that the thickness of the hot-melt adhesive material was 2.0 mm, and evaluation was performed in the same manner. The results are listed in Table 1.

[Example 3]
The long side width is 21.0 mm, the length is 2000 mm, the short side width is 19.5 mm, the length is 1800 mm, and the corner curvature is R = 0 mm. 0.0 mm. The length and depth of the other grooves were the same as in Example 1. In this example, the divided frames as shown in FIG. 5 were used, 51c, 51c ′, 51d, and 51d ′ were each 900 mm, and 51a, 51a ′, 51b, and 51b ′ were 982 mm each. The joining part was made into the shape by which three trapezoid-shaped convex parts were provided like Fig.8 (a). The maximum lateral dimension on the root side of the convex part is set to a length of 2.1 mm, the maximum lateral dimension on the tip side of the convex part is set to 4.2 mm, the dimension of the joint gap is set to 0.015 mm, The adhesive was fitted from above and below without using an adhesive. As a result of visual inspection, there was no problem in appearance. Thereafter, a pellicle was prepared in the same manner as in Example 1 except that the thickness of the hot-melt adhesive material was 2.0 mm, and evaluation was performed in the same manner. The results are listed in Table 1.

[Comparative Example 1]
A cut frame from a single base material without a joint was prepared. The long side width was 9.0 mm, the length was 800 mm, the short side width was 7.0 mm, and the length was 480 mm. The material was an aluminum alloy, and a large pellicle frame having a thickness of 4.0 mm was used. Grooves were provided over the entire length of the short side, the groove depth was 2 mm, and the groove height was 1.5 mm. Further, the curvature of the corner portion was R = 2 mm. Other than that, a pellicle was produced in the same manner as in Example 1 and evaluated in the same manner. The results are listed in Table 1. However, since there are no joints, no joint strength test was performed.

[Comparative Example 2]
After the large pellicle frame was prepared in the same manner as in Example 1 except that the shape of the joint was as shown in FIG. 9 and was joined using a two-component room temperature curing urethane adhesive, Example A pellicle was prepared in the same manner as in No. 1 and evaluated in the same manner. The results are listed in Table 1. When a large pellicle frame was produced and then visually inspected, adhesive sagging occurred, and an appearance of the adhesive due to sagging adhesive was observed.

[Reference Example 1]
As shown in FIG. 10, the joining portion has a shape in which two regular triangular convex portions are provided at the end of one member. The maximum horizontal dimension on the base side of the convex part is set to a length of 2.0 mm, the dimension of the joint gap is set to 0 mm, and a large pellicle frame is manufactured by joining by laser welding. Similarly, a pellicle was prepared and evaluated in the same manner. The results are listed in Table 1. When a visual inspection was carried out after the production of the large pellicle frame, unevenness after welding occurred at the joint, and the appearance was not good. In addition, the appearance after the pellicle was produced also showed that the uneven portion was shining and looked as a foreign object, and the inspection property was not good.

[Reference Example 2]
The joining part was made into the shape by which three trapezoid-shaped convex parts were provided in the edge part of one member like FIG. The maximum horizontal dimension on the base side of the convex part is set to a length of 4.2 mm, the maximum horizontal dimension on the tip side of the convex part is set to a length of 2.1 mm, and the dimension of the joint gap is set to 0 mm, A frame for a large pellicle was produced by bonding using a shrinking swivel. Thereafter, a pellicle was produced in the same manner as in Example 3 and evaluated in the same manner. The results are listed in Table 1. When the visual inspection was performed after manufacturing the large pellicle frame, the appearance was good, but because the bonding strength was weak, gaps and backlash were observed in the visual inspection after the pellicle was manufactured, and there was foreign matter there. It was caught. Moreover, the shape was not rectangular.

  The present invention is a pellicle frame using a divided frame and can be used in the field of large pellicles.

  DESCRIPTION OF SYMBOLS 1 ... Pellicle, 2 ... Pellicle frame body, 2a * 2b ... Long side, 2c * 2d ... Short side, 3 ... Pellicle film, 4 ... Opening part, 4a * 4b ... Long side, 4c * 4d ... Short side, 5 ... corner, 5a · 5b ... long side, 5c · 5d ... short side, 21a · 21b ... split frame (long side member), 21c · 21d ... split frame (short side member), 21e · 21f · 21g / 21h: Divided frame (member for corner), 41a / 41b ... Divided frame (long side member), 41c / 41d ... Divided frame (short side member), 41a / 41b ... Divided frame ( Long side members), 41c and 41d, divided frame bodies (short side members), C, concave portions, G, bonding gaps (excess outer peripheral portions), P, convex portions.

Claims (9)

A pellicle frame having an opening having a rectangular shape in plan view,
Having a member that forms the periphery of the opening by joining the ends together,
The end of one member to be joined is provided with at least one convex portion protruding toward the other member to be joined,
A concave portion for fitting the convex portion is provided at the end of the other member,
The end of the one member is joined to the end of the other member by fitting the convex portion into the concave portion,
Pellicle frame. The convex portion is formed such that the maximum lateral dimension (t) on the root side is shorter than the maximum lateral dimension (v) on the tip side.
The pellicle frame according to claim 1. The maximum lateral dimension (t) on the base side of the convex part is set to a length of 5% to 80% with respect to the width of the member provided with the convex part.
The pellicle frame according to claim 2. The maximum lateral dimension (v) on the tip side of the convex part is set to a length of 10% to 90% with respect to the width of the member provided with the convex part.
The pellicle frame according to claim 2 or 3. The maximum lateral dimension (t) on the base side of the convex portion is set to a length of 5% to 80% with respect to the thickness of the member provided with the convex portion.
The pellicle frame according to any one of claims 2 to 4. The maximum lateral dimension (v) on the tip side of the convex portion is set to a length of 10% to 90% with respect to the thickness of the member on which the convex portion is provided.
The pellicle frame according to any one of claims 2 to 5. The convex portion has a surplus outer peripheral portion that is compressed and deformed inward by the inner peripheral surface of the concave portion when fitted with the concave portion.
The pellicle frame according to any one of claims 1 to 6. The dimension of the excess outer peripheral part is set to 0.005 mm or more and 0.1 mm or less,
The pellicle frame according to claim 7. A frame for a pellicle according to any one of claims 1 to 8,
A pellicle film that is stretched and supported so as to cover the opening of the pellicle frame;
Comprising
Pellicle.

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