JP6461659B2 - Pellicle frame and pellicle - Google Patents

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 pellicle frame and a pellicle that are 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 the manufacture of semiconductor circuit patterns and the like, dust prevention means called a pellicle is disposed on both sides or one side 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 side of a pellicle frame made of metal, ceramics, or polymer, and an adhesive for attaching to a mask on the opposite side. What provided the layer (adhesive material) is mentioned. For example, the pellicle is 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 pellicle frame having a shape matching the shape of a photomask or a reticle. A pellicle film made of is spread and bonded, and is attached to the other edge surface of the pellicle 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, it can be applied to large photomasks used in the photolithography process of large color TFT LCDs capable of high-quality and high-definition display. ing.

  In response to the above-mentioned problem, the present applicant has disclosed a pellicle frame body by joining frame members instead of punching from one sheet-like base material as Patent Documents 1 to 3. Patent Document 4 discloses a pellicle frame formed of a thermoplastic resin containing a fibrous reinforcing substance on the pellicle frame.

JP 2012-0530302 A JP 2012-053304 A JP 2012-053305 A JP 2013-2104013 A

  By the way, when manufacturing the joining frame body like patent documents 1-3, in order to eliminate the level | step difference of a junction part, after performing the surface treatment after joining the frame members of an aluminum base material, the pellicle frame It was as a body. As a surface treatment, anodizing is generally performed. However, when such a treatment is performed, pinholes or the like are sometimes generated in minute gaps in the joints, which causes white spots on the joints. The dot was scattered and it became a pseudo foreign material, and the appearance and inspectability deteriorated.

  In order to solve such a problem, it is conceivable to join the frame members after the surface treatment of the frame members, but even if an adhesive or the like is used when the frame members whose surfaces are entirely treated are joined together There is a possibility that the strength may be weakened, and there is a risk that the dimensions may become unstable or deform during handling.

  The present invention has been made in view of the above circumstances, and even when surface-treated members are joined together, it is possible to ensure the rigidity of the frame body by suppressing a decrease in the joining strength of the joining portion. It is another object of the present invention to provide a pellicle frame body and a pellicle that can stabilize handling properties and can improve yield.

  In order to achieve the above object, a pellicle frame according to the present invention is provided with an opening having a rectangular shape in plan view, and the opening is formed by joining the ends of the surface-treated members. The peripheral edge of the member is formed, and the end surface of at least one member at the joint portion between the end portions of the member is provided with a portion not subjected to surface treatment.

  The manufacturing method according to the present invention is a method for manufacturing a pellicle frame having an opening that is rectangular in plan view, and joins the ends of the surface-treated members to form the periphery of the opening. And a step of providing a portion that is not subjected to surface treatment on the end surface of the end portion of at least one member in the joint portion between the end portions of the members.

  When such a configuration and method are employed, in the joint portion between the end portions of the surface-treated members, a portion that is not subjected to the surface treatment is provided on the end surface of the end portion of at least one member. Strength (rigidity) can be ensured, dimensions and handling properties can be stabilized, and yield can be improved.

  In the pellicle frame according to the present invention, it is preferable to subject the end surface to a surface treatment from the surface layer of the member to a depth of at least 0.1 mm. The member is preferably made of an aluminum alloy. Further, at the joining portion, the end portions of the members can be joined with a chemical reaction type adhesive, and an adhesive made of an anaerobic curable adhesive or a cyanoacrylate type adhesive may be adopted. it can.

  In addition, a pellicle according to the present invention includes the above-described pellicle frame and a pellicle film that is stretched and supported so as to cover an opening of the pellicle frame.

  According to the present invention, even when the surface-treated members are joined together, it is possible to secure the rigidity of the frame body by suppressing the decrease in the joining strength of the joined portion, and to stabilize the dimensions and handling properties. In addition, it is possible to provide a pellicle frame and a pellicle that can improve the yield.

1 is a perspective view showing a pellicle according to an embodiment of the present invention. It is a top view of the pellicle shown in FIG. It is an expansion perspective view of the corner | angular part of the pellicle frame which comprises the pellicle shown in FIG. FIG. 4 is an enlarged plan view of a joint portion of the pellicle frame shown in FIG. 3. (A) And (b) is an enlarged plan view of the other form of a joined part, (c) And (d) is a perspective view of the end face of a joined part concerning Example 2 of the present invention. (A) And (b) is an expanded plan view of the other form of a junction part, (c) is a perspective view of the end surface of the junction part which concerns on Example 3 of this invention. It is a top view of the pellicle frame which concerns on the modification of embodiment of this invention. It is a top view of the pellicle frame which concerns on the modification of embodiment of this invention. It is an enlarged plan view of the junction part concerning the reference example of the present invention. (A) is an enlarged plan view of the junction part which concerns on Example 1 of this invention, (b) is a perspective view of the end surface of the junction part which concerns on Example 1 of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

  FIG. 1 is a perspective view showing a pellicle according to an embodiment of the present invention, and FIG. 2 is a top view of the pellicle shown in FIG. As shown in each drawing, the pellicle 1 includes a pellicle frame 2 and a pellicle film 3 that is stretched and supported on the upper edge surface 2e of the pellicle frame 2. Although not shown, the pellicle 1 further includes an adhesive layer applied to the lower edge surface of the pellicle frame 2, and a protective film that is adhered to the adhesive layer and protects the adhesive layer. I have. The pellicle 1 is a large pellicle, and the pellicle frame 2 is a large pellicle frame.

The 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, Al ₂ O ₃ 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, magnesium alloy, or a polycarbonate resin, a resin such as an acrylic resin, has a substantially rectangular shape. Since the pellicle 1 is attached to the mask via the adhesive layer, a material having high rigidity and relatively small weight is preferable, and materials such as aluminum, aluminum alloy, magnesium alloy, and resin are preferable. Furthermore, an aluminum alloy is preferable because of easy surface treatment. The pellicle frame body 2 is configured by a plurality of divided members 20a to 20d and connecting members 21a to 21d, which will be described later, and the divided members 20a to 20d and the connecting members 21a to 21d are made of a material having the same elastic modulus. Preferably it is formed.

The pellicle frame 2 has a pair of opposed long sides 2a and 2b and a pair of opposed short sides 2c and 2d shorter than the long sides 2a and 2b. In the 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. The pellicle frame 2 has a rectangular opening 4. The opening area of the opening 4 is preferably 1000 cm ² or more, more preferably 3000 cm ² or more, more preferably 5000 cm ² or more and 35,000 ² or less.

  The pair of long sides 2a and 2b is formed of a column member having a width of, for example, 9.0 mm, and the length thereof is, for example, 800 mm. The pair of short sides 2c and 2d is made of a column 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 pellicle frame 2 is, for example, R = 2 mm. In addition, the vertex when it is assumed that there is no curvature in the corner portion 5 is hereinafter simply referred to as “vertex”. Grooves 7 are provided along the longitudinal direction (side direction) on the side surface 6 of the pellicle frame 2.

  The width of each side 2a to 2d of the pellicle frame 2 is preferably as thin as possible from the viewpoint of securing an exposure area. However, if the width is too small, the pellicle frame 2 is stretched by the tension of the pellicle film 3 when the pellicle film 3 is expanded. There is a risk that the problem of bending will occur. Each side 2a to 2d can have a thickness of about 3 mm to 25 mm in order to obtain a width with consideration of rigidity with respect to the length of each side.

  Further, regarding the thickness of the pellicle frame body 2, the thinner the pellicle 1, the lighter and easier to handle the pellicle 1. However, if the pellicle film 3 is too thin, the pellicle frame body 2 will be bent by the tension of the pellicle film 3. Problems may arise. The thickness of the pellicle frame body 2 is preferably about 3.5 mm to 12 mm from the balance between the two according to the length of each side 2a to 2d.

  The 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 10 μm or less and 0.1 μm or more, for example. The pellicle film 3 is spread on the upper edge surface 2 e so as to cover the opening 4 of the pellicle frame 2, and is attached to and supported by the pellicle frame 2.

  As an adhesive for adhering the pellicle film 3 to the upper edge surface 2e of the pellicle frame 2, for example, a fluorine-based polymer such as an acrylic resin adhesive, an epoxy resin adhesive, a silicone resin adhesive, or a fluorine-containing silicone adhesive is used. be able to.

  The adhesive material for sticking and supporting the pellicle film 3 is based on styrene ethylene butylene styrene, styrene ethylene propylene styrene, olefin-based hot melt adhesive material, silicone adhesive material, acrylic adhesive material, or foam. The adhesive tape used as the material can be used. The thickness of the pressure-sensitive adhesive layer is set within a range not exceeding the distance between the pellicle film 3 and the photomask in which the total thickness of the pellicle frame 2 and the thickness of the pressure-sensitive adhesive is defined. 01 mm or more is preferable.

  In addition, when the pellicle film 3 is attached to the photomask, if there is a space inside the adhesive layer, foreign matter may stay in the space. Therefore, when applying the pressure-sensitive adhesive to the lower edge surface of the pellicle frame 2, the pressure-sensitive adhesive layer is crushed and spread by the pressure applied when the pellicle 1 is attached to the photomask. It is preferable to apply to the inside of the opening 4 of the pellicle frame 2 so that the adhesive does not protrude into the opening 4. Specifically, it is preferable to apply so that 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 pellicle frame 2, and is applied along each side 2a to 2d of the pellicle frame 2. It is preferable.

  As a protective film for protecting the adhesive material, a film made of polyethylene terephthalate resin or polyethylene resin can be used. Moreover, according to the adhesive force of an adhesive material, you may apply | coat a mold release agent, for example, a silicone type release agent, or a fluorine type release agent to the surface of a protective film. The thickness of the protective film is preferably, for example, 1 mm or less and 0.01 mm or more.

  Next, the pellicle frame 2 will be described in detail with reference to FIGS. 2 and 3. FIG. 3 is an enlarged perspective view showing a corner portion.

  The pellicle frame body 2 is a divided frame body composed of a plurality of frame members that form the periphery of the opening 4, and the divided members 20a and 20b that constitute each of the pair of long sides 2a and 2b, and a pair of short members. Dividing members 20c. Constituting each of the sides 2c, 2d. It comprises 20d and the connection members 21a-21d which comprise the corner | angular part 5, and connect division member 20a, 20b and division member 20c, 20d. That is, the pellicle frame body 2 includes one end of each of the divided members 20a and 20b and the divided members 20c. The one end part of 20d is connected so that it may form a substantially right angle via the connection members 21a-21d, and is exhibiting the substantially rectangular shape. The pellicle frame body 2 has eight joint portions 22a to 22h along the circumferential direction of the frame body.

  The divided member 20a and the divided member 20b are substantially the same and have the same shape, and the divided member 20c and the divided member 20d have the substantially same shape. Further, the connecting members 21a to 21d that form the corner portions 5 each have an L shape, and all have substantially the same shape. The length of the divided members 20a and 20b is, for example, 700 mm, and the divided members 20c. The length of 20d is, for example, 380 mm. As for the length of connecting member 21a-21d, one side is 50 mm, for example. The distance between the joint portions 22a to 22h and the corner portion 5 closest to the joint portions 22a to 22h is the length of the long sides 2a and 2b or the short sides 2c and 2d provided with the joint portions 22a to 22h. Is set to 45% or less.

  When the pellicle frame 2 is based on the dividing member 20a, the dividing member 20a, the connecting member 21a, the dividing member 20d, the connecting member 21b, the dividing member 20b, and the connecting member 20a are connected in the clockwise direction with respect to the opening axis of the opening 4. The member 21c, the divided member 20c, and the connecting member 21d are connected in this order. In addition, in FIG. 2, although the junction parts 22a-22h are eight places, as a number of junction parts, what is necessary is just one place or more, Preferably it is 2-30 places, More preferably, it is 2-20 places, More preferably Are 3 to 15 locations, and further 4 to 12 locations. In addition, the distance between at least one of the joint portions and the corner portion closest to the joint portion is preferably 45% or less of the length of the side where the joint portion is provided. According to such a configuration, since the frame is rectangular and the vicinity of the corner is high in rigidity, the rigidity can be maintained by arranging the joint in the vicinity of the corner, and the pellicle frame can be bent. It becomes possible to suppress. Furthermore, by providing a joint in the vicinity of the corner, the right angle is improved and the rectangular shape is maintained. Therefore, the amount of bending of the pellicle frame should be within a tolerance range (0% to 3%). Can do.

  Here, when there is one joint, it is possible to adjust at the joint without requiring flatness and dimensional accuracy as much as an integrated type without a joint when cutting from a single sheet-like base material. In addition, since it is possible to plastically deform one divided member to form a frame, it is possible to save the base material and reduce the cost. Furthermore, when the number of joints is two or more, it is more preferable because the flatness can be easily adjusted. By using two or more joint portions in this way, the processing accuracy of each part constituting the pellicle frame body 2 can be increased, and the integrated pellicle frame body is cut out from a single sheet-like base material. However, the flatness accuracy can be easily obtained, and the dimensional accuracy is increased.

  The above-mentioned joining parts 22a-22h are exhibiting a complicated shape (uneven shape), as shown in FIG. Specifically, for example, the joining portion 22f includes a convex portion 23 formed on the connecting member 21c and a concave portion 24 formed on the dividing member 20c. The convex portion 23 formed on the connecting member 21c has a substantially circular shape in plan view, and the width dimension d2 on the distal end side is larger than the width dimension d1 on the proximal end side. Correspondingly, the recess 24 formed in the split member 20c has a substantially circular shape in plan view. The joining portion 22f is joined by fitting with a convex portion 23 formed on the connecting member 21c and a concave portion 24 formed on the dividing member 20c. The joint portions 22a to 22e, 22g, and 22h have the same configuration.

  Each of the frame members 20a to 20e and 21a to 21e is preferably subjected to a surface treatment with each part before making the frame member into a rectangular frame. Examples of the surface treatment of the frame member include alumite treatment, painting, paint coating, plasma electrolytic oxidation treatment, plating treatment, low melting point glass frit treatment, CVD treatment, PVD treatment by sputtering, etc. Oxidation treatment or painting is preferred from the viewpoint of light resistance. Further, the surface treatment with the frame member is preferable in terms of quality stability and cost because the equipment may be smaller than that of the pellicle frame.

  The shapes of the joint portions 22a to 22h may be shapes other than the above shapes. For example, as shown in FIG. 5A, a plurality of (here, two) convex portions 23a and 23b are formed on the connecting member 21a, and correspondingly, a plurality of concave portions 24a, 24b may be formed. Moreover, as shown in FIG.5 (b), the structure by which the convex part 23 and the recessed part 24 were each formed in the connection member 21a and the division member 20a may be sufficient. Moreover, as shown to Fig.6 (a) and (b), convex part 23a-23c and recessed part 24a-24c may exhibit substantially trapezoid shape in planar view. As a preferable shape of the joining portions 22a to 22h, a shape composed of a tenon and a groove, and a shape in which the entire outer peripheral surface (side surface) of the convex portion (tenon) 23 is covered by the inner peripheral surface of the concave portion (groove) 24 is preferable. That is, it is not a simple shape that just abuts the flat end surfaces 51a and 51b of the divided members 50a and 50b as shown in FIG. 9 (reference example), and the bonding area is relatively larger than this simple shape. It only has to be. In addition, when providing a junction part in the corner | angular part 5 vicinity, it is not limited to the structure which abuts an end surface along the circumferential direction of the pellicle frame 2, It is the structure which abuts the end surface of a division member on the side surface of a division member. There may be a configuration in which end surfaces inclined at the corner portion 5 are in contact with each other.

  For example, as illustrated in FIGS. 5C, 5 </ b> D, 6 </ b> C, and 10 </ b> B, end portions of the joint portions 22 a to 22 h are provided with portions that are not subjected to surface treatment. ing. By having such a portion, the bonding strength can be sufficiently maintained when bonding is performed using an adhesive, the rigidity is improved, and the dimensional stability is also improved. In addition, the pellicle is not deformed when it is handled using a handling jig. For parts that have not been surface-treated, part of the end face of the joint may be partially cut after surface-treating for each part, or masking is applied during surface treatment so that it is not surface-treated. Or either.

  The end face may not be subjected to surface treatment on the entire end face, but it is preferable that at least 0.1 mm or more of the end face is surface-treated from the surface layer of the frame member. In this case, the portion that is not surface-treated is preferably 5% or more and 80% or less, more preferably 10% or more and 70% or less, and 20% or more and 60% or less of the entire surface area of the end face. By doing in this way, when frame members are joined, there is no whitened state along a joined part, and since it is not mistakenly recognized as a foreign object, inspection property also becomes good. Further, it is preferable that the pellicle frame body is not corroded by contact with the cleaning water when it is cleaned.

  Further, the depth of the untreated surface is preferably 15 μm or more deeper than the surface of the end face, more preferably 18 μm or more. Moreover, it is preferable that it is 50 micrometers or less. By being in this range, an alumite layer can be completely removed without deforming the shape even in a joint portion having a complicated shape, so that an anchor effect is obtained and the rigidity of the fitting portion of the joint portion can be increased. The shape of the part that has not been surface-treated is not particularly limited, but a rectangular shape is preferable from the viewpoint of ease of processing. Furthermore, the shape in the depth direction is not particularly limited, but a rectangular shape, a triangular shape, a round shape, and the like are preferable in terms of ease of processing.

  It is preferable to bond this untreated surface with a chemically reactive adhesive because the bonding rigidity is increased. Among these, the adhesive is preferably in a liquid state, and when a liquid adhesive is used, the adhesive penetrates into the joint and the liquid spreads over the entire joint, which is preferable from the viewpoint of manufacturing and rigidity. Among liquid adhesives, an anaerobic curable adhesive that cures by blocking air, or a cyanoacrylate adhesive that initiates reaction with a small amount of moisture as an initiator is preferable. Among these, an anaerobic curable adhesive is more preferable. Specific examples of the anaerobic curable adhesive include Loctile 638, Loctite 601, and Loctite 648 (both manufactured by Henkel Japan). If it is an anaerobic curable adhesive, the reaction is unlikely to occur at the part protruding from the joint, and it is easy to wipe off, so that outgas and dust generation can be minimized, and the aluminum alloy preferably used for the frame member Since such a metal serves as a catalyst to accelerate curing, it is particularly preferable to have a portion that has not been surface treated from the viewpoint of further progress of the reaction.

  By doing in this way, joining strength of joined parts 22a-22h becomes 10kgf or more. The pellicle frame 2 bends inward when the pellicle film 3 is attached. At this time, when the bonding strength is 10 kgf or more, stress concentration is relieved, so that gaps, backlash, and the like are less likely to occur at the bonding portions 22a to 22h. Thereby, even if the pellicle frame body 2 is constituted by the divided members 20a to 20d and the connecting members 21a to 21d, the dimensions are stabilized. Further, the pellicle 1 is preferably less bent to the inside of the pellicle frame 2 when the pellicle film 3 is stretched. However, by setting the bonding strength of the bonding portions 22a to 22h to 10 kgf or more, the pellicle frame 2 Inward bending can be suppressed.

  This inward bending of the pellicle 1 is regulated to a predetermined amount by a mask manufacturer from the viewpoint of securing an effective exposure area of the pellicle 1. In the pellicle frame 2, it is necessary to set the amount of bending within the allowable range, but by setting the bonding strength to 10 kgf or more, the bending can be suppressed as described above, and the amount of bending is within the predetermined range. Can be set. Furthermore, when handling the pellicle 1 (operation such as movement), a jig is attached to the groove portion 7 of the pellicle frame body 2 to handle the pellicle 1 vertically and horizontally. If the inward deflection is large, the jig On the other hand, if the pellicle 1 is likely to fall off and is greatly bent outward, the pellicle 1 may be rubbed when attached to a jig, and foreign matter may be generated. In this respect, in the pellicle frame body 2, by setting the bonding strength at the bonding portions 22a to 22h to 10 kgf, it is possible to prevent the occurrence of foreign matter while preventing the pellicle 1 from falling.

  Further, the pellicle film 3 is attached to the pellicle frame 2 by applying a load to the pellicle frame 2, and this load varies from 10 kgf to 70 kgf depending on the apparatus. Therefore, it is necessary to take measures to prevent the joints 22a to 22h from being deformed by different loads depending on the apparatus. Further, when the shape of the pellicle frame 2 is deviated from a predetermined dimension, there is a possibility that a load is locally applied to the joint portions 22a to 22h and the joint portions 22a to 22h are deformed in order to correct the dimensions. In order to solve these problems, the bonding strength of the bonding portions 22a to 22h is preferably 10 kgf or more, more preferably 15 kgf or more, and further preferably 25 kgf or more.

  As a joining method that achieves the joining strength of the joining parts 22a to 22h as described above and can be used from the exterior as the pellicle 1, the divided members 20a to 20d and the connecting members 21a to 21d are fitted or an adhesive is used. It is preferable to use it. When making it fit, the shape which provided the convex part in the edge part of joining, and the recessed part made to fit in the other edge part is preferable. Furthermore, a shape in which the root dimension (proximal end side dimension) of the convex portion is smaller than the maximum lateral dimension on the distal end side is more preferable because it is resistant to tension in the length direction. Moreover, it is preferable that the level | step difference of a junction part shall be 0.10 mm or less. Within this range, it is preferable because there is no film wrinkle, or there is no air path when a pellicle is attached to the mask. In particular, it is preferably 0.08 mm or less, and more preferably 0.05 mm or less. The flatter the better. In order to make the pellicle frame body after the surface treatment for each frame member, in order to make the level difference 0.10 mm or less, it is necessary to improve the dimensional accuracy of each frame member.

  As described above, in the pellicle frame body 2 of the pellicle 1, the joint strength at the joint portions 22a to 22h between the split members 20a to 20d and the connecting members 21a to 21d is 10 kgf or more. In addition, it is possible to suppress bending and distortion and to ensure rigidity. Moreover, by setting it as the division | segmentation frame which consists of division member 20a-20d and connection member 21a-21d, a dimension can be adjusted easily and a manufacturing process can be simplified while being able to ensure a dimensional accuracy. Therefore, the same dimensional accuracy as that of the frame body having no joint portion can be easily obtained. Therefore, when using the divided frame, rigidity and dimensional stability can be maintained without using a highly rigid member or the like for the joint portions 22a to 22h, and the yield can be improved. In particular, when the pellicle 1 is large, the configuration of this embodiment is more effective.

  Then, the modification of the said embodiment is demonstrated. FIG. 7 is a top view of a pellicle frame according to a modification. As shown in FIG. 7, the pellicle frame 2A is different from the pellicle frame 2 in the joining form. The pellicle frame 2A is formed of divided members 30a and 30b that constitute the long sides 2Aa and 2Ab, and divided members 30c and 30d that constitute the short sides 2Ac and 2Ad. The long sides 2Aa, 2Ab, that is, the divided members 30a, 30b have the same length, and the short sides 2Ac, 2Ad, that is, the divided members 30c, 30d have the same length. The pellicle frame 2A is configured by joining the divided members 30a and 30b and the divided members 30c and 30d, and has four joint portions 31a to 31d. The structure of the joining parts 31a to 31d is the same as that of the joining parts 22a to 22h. The joint portions 31a to 31d may have other shapes.

  FIG. 8 is a top view of a pellicle frame according to a modification. As shown in FIG. 8, the pellicle frame 2B is different from the above-described pellicle frame 2 in the joining form. The pellicle frame 2B is formed of divided members 40a to 40d that constitute the long sides 2Ba and 2Bb and divided members 40e to 40h that constitute the short sides 2Bc and 2Bd. The lengths of the divided members 40a to 40d constituting the long sides 2Ba and 2Bb are formed equal, and the lengths of the divided members 40e to 40h constituting the short sides 2Bc and 2Bd are formed equal. The pellicle frame 2B is configured by joining divided members 40a to 40d and divided members 40e to 40h, and has eight joint portions 41a to 41h. The structure of the junction parts 41a-41h is the same as the structure shown to Fig.5 (a). The joint portions 41a to 41h may have other shapes.

  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 unless it exceeds the gist.

[Example 1]
The material of the pellicle frame (the material of all the frame members) was an aluminum alloy (A5052 series). Two short-side frame members having a thickness of 4.0 mm, a width of 6.0 mm, and a length of 240 mm were prepared. Two long side frame members having a thickness of 4.0 mm, a width of 6.0 mm, and a length of 370 mm were prepared. Four corner members having a thickness of 3.97 mm, a width of 6.0 mm, and a corner portion having a curvature of R = 2 mm were prepared. Further, a groove was provided on the side surface on the short side frame member and the short side of the corner portion, the groove depth was 2 mm, and the groove height was 1.5 mm. As shown in FIG. 10A, the joining portion has a stepped shape in which an end surface 81a having a step of the frame member 80a and an end surface 81b having a step of the dividing member 80b are brought into contact with each other. In FIG. 10, the specific dimensions were 2.0 mm in the width direction, 10 mm in the longitudinal direction, 2.0 mm in the width direction, 10 mm in the longitudinal direction, and 2.0 mm in the width direction.

  Thereafter, each frame member was anodized to cover the entire surface with an alumite layer. Then, the alumite layer of each joining end surface was removed, and it processed as shown in FIG.10 (b) so that the aluminum alloy could be seen. At this time, an alumite layer was left 1.5 mm from the outer layer. At this time, the ratio of the non-alumite layer was 22.1%. Thereafter, an anaerobic curable acrylic adhesive (trade name: Henkel Loctite 638 (manufactured by Henkel)) was used as an adhesive, and a pellicle frame as shown in FIG. 2 was produced. Next, a styrene ethylene butylene styrene hot melt pressure sensitive adhesive having a thickness of 1.4 mm was applied to the pellicle frame along each side of the pellicle frame.

  Separately, a pellicle film of cellulose ester was formed on the substrate by spin coating, the pellicle film was adhered to a temporary frame, and then peeled off from the substrate. This temporary frame was made of aluminum. Then, in the pellicle frame body coated with the hot melt adhesive material, an acrylic film adhesive was applied to the opposite surface where the hot melt adhesive was not applied, and the pellicle film of the temporary frame was adhered and cured. . Then, the excess film was cut to produce a pellicle.

(Handling properties)
The operation of gripping the groove of the pellicle frame, placing the pellicle frame in a direction parallel to the ground of the side of the pellicle frame, and then returning the side in the vertical direction to the parallel direction is performed once. Repeated times. Further, this operation of one vertical rotation around the horizontal axis of the pellicle frame and one horizontal rotation around the vertical axis was repeated five times to confirm the handling property and the joint. The case where there was no change in the joint through the handling was evaluated as “◯”, “△” where a gap was formed in the joint, and “X” where the joint was likely to come off. The results are shown in Table 1.

(Visual inspection of joints)
Ten inspectors visually inspected the pellicle with a condenser lamp in the dark room and visually inspected the joint. The case where 9 or more persons had no problem was evaluated as “◯”, the case where 5 to 8 persons had no problem was evaluated as “Δ”, and the case where 4 or less persons had no problem was evaluated as “×”.

(Measurement of level difference and defect inspection due to level difference)
Moreover, the level | step difference of the junction part was measured with the clearance gauge (made by Nagai Gauge Manufacturing Co., Ltd.). The pellicle frame was allowed to stand on a surface plate, and the part where the gap was left across the joint surface was measured. The results are shown in Table 1. Check for defects such as film wrinkles, unapplied adhesion, and mask adhesive lift during pellicle fabrication. If there is no problem for 9 or more people, "○". If 5 to 8 people have no problem, "△". The case where 4 or less people had no problem was evaluated as “x”.

(Joint strength test)
Next, a bonding strength test was performed. A sample of a 100 mm rod-shaped frame including a joint portion having the same shape as described above was produced. The joint part was a 50 mm position, which is a half of a 100 mm rod shape. 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.

[Example 2]
The material of the pellicle frame (the material of all the frame members) was an aluminum alloy (A6063 series). Two short side frame members having a thickness of 5.0 mm, a width of 7.0 mm, a length of 480 mm, and a corner curvature of R = 3 mm were prepared. Two long side frame members having a thickness of 5.0 mm, a width of 9.0 mm, and a length of 790 mm were prepared. Further, a groove was provided on the side surface on the short side frame member and the short side of the corner portion, the groove depth was 2 mm, and the groove height was 1.5 mm. As shown in FIG. 5A, the joint portion has a shape in which two round convex portions are provided at the end of one member. The maximum horizontal dimension on the base side of the convex part was set to a length of 1.5 mm, the maximum horizontal dimension on the tip side of the convex part was set to 2.0 mm, and the distance from the base side to the tip of the convex part was 2 mm. A first shape was provided at 2 mm in the width direction, and a second shape was then provided at 2 mm in the width direction.

  Thereafter, each frame member was anodized to cover the entire surface with an alumite layer. Thereafter, the alumite layer on each joint end face was removed, and processing was performed as shown in FIGS. 5C and 5D to such an extent that the aluminum alloy was visible. At this time, 0.5 mm from the outer layer left the alumite layer, and 0.5 mm of the central alumite layer also remained. At this time, the ratio of the non-alumite layer was 74.3%. Thereafter, an anaerobic curable acrylic adhesive (trade name: Henkel Loctite 648 (manufactured by Henkel)) was used as an adhesive and bonded to produce a pellicle frame as shown in FIG. Thereafter, a pellicle was prepared and evaluated in the same manner as in Example 1.

[Example 3]
The material of the pellicle frame (the material of all the frame members) was an aluminum alloy (A7075 series). Four long side frame members having a thickness of 6.5 mm, a width of 18.0 mm, and a length of 884 mm were prepared. Four short side frame members having a thickness of 6.47 mm, a width of 16.0 mm, a length of 782 mm, and a corner curvature of R = 3 mm were prepared. Further, a groove was provided on the side surface on the short side frame member and the short side of the corner portion, the groove depth was 2 mm, and the groove height was 1.5 mm. As shown in FIG. 6 (b), the joining portion has a joining distance of each joining end face of 2.7 mm, 3 mm, 3 mm, and 2.7 mm from the outside with respect to the long side width, and outside with respect to the short side width. To 2.4 mm, 2.66 mm, 2.66 mm, and 2.4 mm. 6A. In FIG. 6B, the inner surfaces of the respective joints were set to 4.8 mm on the long side and 4.26 mm on the short side. The length from the top end of 24a to the base of the joint was set to 2.7 mm on the long side and 2.4 mm on the short side.

  Thereafter, each of the frame members was subjected to an alumite treatment, and the entire surface was covered with an alumite layer. Thereafter, the alumite layer on each joint end face was removed, and processing was performed as shown in FIG. At this time, 1.0 mm from the outer layer left an alumite layer, and two alumite layers also remained in the center. The alumite layer at the center at that time was set to 0.5 mm. The proportion of the non-alumite layer at this time was 47.8% on the long side and 51.0% on the short side. Thereafter, an anaerobic curable acrylic adhesive (trade name: Henkel Loctite 648 (manufactured by Henkel)) was used as an adhesive, and a pellicle frame as shown in FIG. 8 was produced. Thereafter, a pellicle was prepared and evaluated in the same manner as in Example 1.

[Example 4]
A pellicle was prepared and evaluated using the same pellicle frame member as in Example 2 except that the alumite layer on the entire joining end face of the joined portion was removed and processing was performed to such an extent that the aluminum alloy was visible.

[Comparative Example 1]
A pellicle was produced and evaluated using the same pellicle frame member as in Example 1 except that the alumite layer was left as it was without removing the alumite layer on the joint end face of the joint.

  The present invention is not limited to the embodiment described above. For example, in the above embodiment, the shapes of the divided members 20a and 20b (divided members 30a and 30b, divided members 40a to 40d) and the divided members 20c and 20d (divided members 30a and 30b, divided members 40e to 40h) are aligned to some extent. However, the shape of each divided member may be different.

  DESCRIPTION OF SYMBOLS 1 ... Pellicle, 2 ... Pellicle frame body, 3 ... Pellicle film, 4 ... Opening part, 20a-20d ... Dividing member (member), 21a-21d ... Connection member (member), 22a-22h ... Joint part.

Claims (6)

A pellicle frame body having a rectangular opening in plan view,
The edge of the opening is formed by joining the ends of the surface-treated member,
Wherein at least one end face of the end portion of the member at the junction of the ends of the member, the portion where the surface treatment is performed, a portion where the surface treatment is not applied, is provided, the pellicle Frame.   The pellicle frame according to claim 1, wherein the end surface is subjected to a surface treatment from the surface layer of the member to a depth of at least 0.1 mm or more.   The pellicle frame according to claim 1, wherein the member is made of an aluminum alloy. In the joint, the ends of the members are joined with a chemical reaction type adhesive,
The pellicle frame according to any one of claims 1 to 3, wherein the adhesive is made of an anaerobic curable adhesive or a cyanoacrylate adhesive. A pellicle frame according to any one of claims 1 to 4,
A pellicle film stretched and supported so as to cover the opening of the pellicle frame;
A pellicle. A method of manufacturing a pellicle frame having an opening that is rectangular in plan view,
A first step of joining the end portions of the surface-treated member to form the periphery of the opening;
The end surface of the end portion of at least one of said members at the junction of the ends of the member, a portion where the surface treatment is performed, a portion where the surface treatment is not applied, a second step of providing, only including,
A method for manufacturing a pellicle frame , wherein the second step is performed prior to the first step .