TW200523668A - Manufacturing method for exposure mask, generating method for mask substrate information - Google Patents

Abstract

To realize a method for manufacturing an exposure mask which is effective to solve a problem on the lowering of the yield of a product caused by the deterioration of the flatness of a mask base plate by chucking the mask base plate on the mask stage of a wafer aligner. The surface shape of the principal surface of each of a plurality of mask base plates and the flatness of the principal surface thereof before and after chucking the mask base plate on the mask stage of the aligner are acquired (step S3), the mask base plate having the surface shape having good flatness both before and after it is chucked on the mask stage is prepared (step S5), and a desired pattern is formed on the mask base plate, whereby the exposure mask is formed (step S6).

Description

'200523668 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a method for manufacturing an exposure mask in the semiconductor field, a method for generating mask substrate information, a method for manufacturing a semiconductor device, a mask substrate, an exposure mask, and server. [Previous Technology] With the progress of miniaturization of semiconductor devices, the requirements for the miniaturization of the photolithography process L have been increased. At present, the design rules of the device have been reduced to 0.13 μm, and the accuracy of the pattern size must be controlled to about 10 nm, which is extremely strict and accurate. As a result, the problems of photolithography processes used in semiconductor manufacturing processes have become more and more significant in recent years. This subject is related to the flatness of the mask substrate used in the lithography process, and it is one of the reasons for the high accuracy of the pattern forming process. That is, with the miniaturization, the flatness of the photomask substrate cannot be ignored as the focal tolerances of the lithography process become smaller. 〇 As a result, those who have studied the results of continuous research on the flatness of the mask substrate can clearly understand the following matters. The surface shape of the reticle substrate has various shapes. Even with the same flatness, there are various shapes such as convex, concave, saddle, and other mixed types. Therefore, even with the same flatness, when the mask substrate is clamped by a vacuum chuck in the case of a mask stage of a circular exposure device, the mask is held by the mask stage or the mouthpiece of the vacuum chuck during clamping. When the substrate is largely deformed, when the substrate is hardly odorous, or when the flatness is improved. The flatness of the mask substrate after being clamped depends on the light before clamping

O: \ 100 \ t00107.DOC -5- 200523668 The surface shape of the mask substrate, and even the same mask substrate will change due to the vacuum chuck. However, since only the flatness is managed in the past, the surface shape of the mask substrate is different, and the flatness of the mask substrate may be greatly deteriorated by clamping the mask substrate to the mask stage of the wafer exposure device. Then, it was understood that forming a pattern on a photomask substrate having such deteriorated flatness and using the obtained exposure photomask to manufacture a semiconductor device is the main cause of product productivity. [Problems to be Solved by the Invention] As described above, the inventors have compared the flatness of the photomask substrate before and after the photomask substrate is held on the photomask stage of the wafer exposure apparatus, and confirmed that the surface of the photomask substrate depends on the photomask substrate. There are people whose shape has poor flatness after clamping, and it has been found that the deterioration of the β flatness is the main cause of the decrease in product productivity. The present invention has been made in consideration of the above matters, and an object thereof is to provide an effective method of manufacturing an exposure mask, a method of generating a mask substrate information, a method of manufacturing a semiconductor device, a mask substrate, an exposure mask, and a server to solve the problem. Since the photomask substrate is held on the photomask stage of the wafer exposure device, the flatness of the photomask substrate is deteriorated, which causes a problem that the product productivity is reduced. [Summary of the Invention] The method for manufacturing an exposure mask of the first viewpoint of the present invention is characterized by: obtaining first information of the surface shape of each display main surface of a plurality of mask substrates, and displaying the exposure on each mask substrate; The process of the second information of the flatness of the aforementioned main surface before and after clamping of the photomask stage of the device; the corresponding relationship between the aforementioned photomask substrates and the aforementioned first information and the aforementioned second information is produced, and O: \ 100 \ 100107.DOC -6- 200523668 Select the process to display the desired flatness from the corresponding relationship made; separate from the uranium substrates of several photomask substrates to prepare the second resource selected and the corresponding relationship Manufacturing process of a mask substrate having the same surface shape as shown in the first information; manufacturing process of forming a desired pattern on the prepared mask substrate. The method for manufacturing an exposure mask at the second viewpoint of the present invention is characterized in that: for each of a plurality of mask substrates, a method for displaying a surface shape of each mask beautiful plate and a main surface of each mask substrate is provided. 1 information, corresponding to the second information of the flatness of the aforementioned main surface before and after clamping of the mask stage of the exposure device of each mask substrate is selected to display the second information of the desired flatness' and A process for preparing a plurality of photomask substrates separately from each other and preparing a photomask substrate having the same surface shape as that of the second information selected, and forming a desired pattern on the prepared photomask substrate The process. The manufacturing method of the exposure mask at the third viewpoint of the present invention is characterized by having a process of obtaining a poor display showing the surface shape of the main surface for each of the plurality of mask substrates; manufacturing the aforementioned mask substrates and the aforementioned Manufacturing process of the correspondence relationship of information; selecting the information showing the convex surface shape from the manufactured correspondence relationship, and selecting the manufacturing process of the mask substrate which is in the aforementioned correspondence relationship with the selection information from the aforementioned plurality of mask substrates ; And a process of forming a desired pattern on the selected mask substrate. The manufacturing method of the exposure mask at the fourth viewpoint of the present invention is characterized by: obtaining first information of the surface shape of the display main surface for each of the plurality of photomask substrates, and displaying the above-mentioned main measured by the measuring device. Flat

O: \ 100 \ 100107.DOC 200523668 The second information processing process of simulating the flatness of the main surface when the aforementioned exposure device sets each reticle substrate with the structure of the mask holding structure of the mask and the exposure I; The manufacturing process of the correspondence relationship between the mask substrate and the aforementioned lf message and the aforementioned 2f message; from the produced correspondence, the second information of the desired flatness is selected and displayed, and is separated from the aforementioned plurality of mask substrates and is prepared to have The second information corresponding to the selection is a process of forming a mask substrate having the same surface shape as the surface shape shown in the lfth news in the aforementioned corresponding relationship; and a process of forming a desired pattern on the prepared mask substrate. The method for manufacturing an exposure mask at the fifth viewpoint of the present invention is characterized by having the first information showing the surface shape of the main surface of each mask | plate and each mask substrate by a member, and displaying the information by measurement. The second information of the flatness of the main surface measured by the device and the mask holding structure of the exposure device, which is simulated in the flatness of the main surface when the exposure device is provided with each mask substrate, is for the plurality of mask substrates. In the corresponding relationship, the second information showing the desired flatness is selected and separated from the aforementioned plurality of photomask substrates to prepare a surface having the same display as the second information corresponding to the selected second information in the aforementioned corresponding relationship. Manufacturing process of a mask substrate having the same surface shape; and manufacturing process of forming a desired pattern on the prepared mask substrate. The manufacturing method of the exposure mask at the sixth viewpoint of the present invention is characterized in that it has a process of obtaining the surface shape of the display mask substrate and the main surface of the mask substrate, and the process of obtaining the surface shape of the main surface is obtained. The mask holding structure of the exposure device is a process for simulating the second information of the flatness of the main surface when the exposure device sets each mask substrate; and judging the flatness of the main surface of the mask substrate obtained by the simulation If the temperature is suitable for its specifications, if the column O: \ 100 \ 100107.DOC -8- 200523668 is suitable for its specifications, then process the aforementioned mask substrate to form an exposure mask. 7. The method for generating the mask substrate information at the seventh viewpoint of the present invention is characterized in that: for each of the plurality of mask substrates, obtaining a first lean message showing the surface shape of the main surface and the light displayed on the exposure device The manufacturing process of the second information about the flatness of the main surface before and after the mask table is clamped; and corresponding to the aforementioned photomask substrates, the aforementioned first information, and the aforementioned second information and memorizing the manufacturing process. The method for generating mask substrate information at the eighth viewpoint of the present invention is characterized by having a process of obtaining information showing the surface shape of the main surface for each of a plurality of mask substrates; and among the obtained information, The shape of the main surface of the memory is displayed as convex information and the manufacturing process of the corresponding mask substrate. The method for generating mask substrate information at the ninth viewpoint of the present invention is characterized in that: for each of a plurality of mask substrates, obtaining first information showing a surface shape of a main surface and displaying the aforementioned information measured by a measuring device; The flatness of the main surface and the mask holding structure of the exposure device simulate the second information of the flatness of the main surface when the aforementioned exposure device is provided with each mask substrate, and for each of the mask substrates and The memory process in which the aforementioned first information corresponds to the aforementioned second information and is memorized. The method of manufacturing a semiconductor device at the tenth viewpoint of the present invention is characterized by having an exposure mask manufactured by a manufacturing method according to one of the first to third viewpoints described above held on a mask stage of an exposure apparatus. The above process; a process of illuminating a pattern formed on the exposure mask by an illumination optical system, and imaging an image of the pattern on a desired substrate; and forming the desired substrate on the aforementioned substrate according to the aforementioned imaging The aforementioned imaged layer is patterned and used in a process for forming a semiconductor device. O: \ 100 \ 100107.DOC -9- 200523668 The method for manufacturing a semiconductor device at the 丨 丨 viewpoint of the present invention is characterized by having a substrate provided with a main surface and a light-shielding device formed on the main surface. And the surface shape of the peripheral area of the main surface toward the edge side of the substrate is lower than the surface height of the central area of the main surface. The exposure mask is clamped on the mask stage of the exposure device. A process of illuminating a pattern formed on the aforementioned exposure mask by an illumination optical system, and then imaging an image of the pattern on a desired substrate by a projection optical system; and imaging the aforementioned desired substrate according to the aforementioned imaging The aforementioned image-forming layer is patterned and used in a process for forming a semiconductor element. The reticle substrate at the twelfth viewpoint of the present invention is characterized in that it includes a substrate having a main surface and a light shielding body covering the main surface, and a surface shape of a peripheral region of the main surface is toward a height of an edge portion of the substrate. The surface is lower than the central area of the main surface. The exposure mask at the thirteenth viewpoint of the present invention is characterized by including a substrate having a main surface and a pattern including a light-shielding body formed on the main surface, and a surface shape of a peripheral area of the main surface is directed to the foregoing. The edge side of the substrate has a shape lower than the surface of the central area of the main surface. The server at the fourteenth viewpoint of the present invention is characterized by having means for performing a process of memorizing and including displaying a webpage of correspondence information, and the correspondence relationship shows a shape of a surface of each mask substrate and a main surface of each mask substrate. Correspondence between the i-th information and the plurality of photomask substrates, the second information displayed on the flatness of the main surface before and after clamping of the photomask stage of each photomask substrate exposure device; The requested information is O: \ 100 \ 100107.DOC -10- 200523668. The slave slave 'enters the processing method of transmitting the aforementioned webpage in a displayable form on the customer's side; and it receives the information from the aforementioned customer transmitting the aforementioned webpage. Means for processing the aforementioned mask substrate application information. The above-mentioned and other objects of this month and the novel features can be made clear by the description and the attached drawings in this specification. [Embodiment] An embodiment (hereinafter, referred to as an embodiment) of the present invention will be described below with reference to the drawings. (First Embodiment) Fig. 1 is a flowchart showing a method for manufacturing an exposure mask according to a first embodiment of the present invention. Baixian 'prepares n mask substrates A ~ κ formed by forming a film covering the light-shielding body on a quartz substrate having a thickness of about 6 sides at an angle of 152 mm, and the mask substrates A ~ κ, ϋ The main surface was measured by a substrate flatness measuring device (manufactured by Nidec), and the surface shape and flatness of the main surface of 11 photomask substrates A to κ before being held on the photomask stage of the exposure device by a vacuum chuck were obtained. (Step S1) ○ Here, the flatness of the corner region (the first region) 1 of the edge region 142 mm of the photomask substrate except the photomask substrate is measured in FIG. 2 (a). Number! region! It is a pattern formation area which actually forms a pattern. In addition, in this embodiment, the surface shape of the 丨 th area 丨 is convex and concave as shown in Fig. 2 (b) and ® 2 (c) respectively, which means that for the line L1 connecting the two ends of the ith area, the upper The shape is convex and concave. Figures 3 (a) and 3 (b) show the overview of the surface shape being convex, and the bottom being concave, respectively.

O: \ 100 \ 100107.DOC -11-200523668 On the other side, the shape of the surface of the second area 2 is convex or concave. As shown in Figure 2⑷, the edge of the mask is toward the edge of the mask substrate. The surface of the first region 1 has a low shape (convex) or a high shape (concave). The second area 2 will be described in detail in the second embodiment.

Next, based on the results obtained above, each of the mask substrates A to κ is classified into each type of the main surface surface shape (step S2). The results are not shown in Table 1. The types of surface shapes (information) can be classified into four types: convex, concave, saddle, and fish plate. In addition, the measured value (second information) of the flatness of the first area 1 before the mask stage was clamped was controlled in a range of 0.4 Mm to 0.5 μm. Figures 3 (c) and 3 (d) show the overview of those whose surface shapes are saddle type and fish plate type, respectively. [Table 1] Flatness of the photomask substrate before clamping (μπ〇 Surface shape before clamping (μιη) A 0.5 convex 0.4 B 0.4 convex 0.4 C 0.45 convex 0.4 D 0.5 concave 0.8 E 0.5 concave 1.0 F 0.4 saddle 0.9 G 0.5 saddle 0.9 _ Η 0.4 fish plate 0.4 I 0.5 fish plate _ 0.4 J 0.5 fish plate (rotation? £ 1 1 0.2 κ 0.5 fish plate (rotation 0.3 O: \ 100 \ 100107.DOC -12- 200523668 Next, on the photomask stage of an ArF wafer exposure device (manufactured by Nikon Corporation), the U-shaped photomask substrates A to κ were sequentially clamped by a vacuum chuck, and the measurement was performed with a true two chuck in the center. The flatness of the main surface of the photomask substrate (step S)). Here, the flatness of the edge area of the photomask substrate and the first area 1 (Fig. 2 (a)) at a 42 mm angle is measured. As shown in Figure 丨, for the u mask substrates A to K, the corresponding relationship between the types of surface shapes and the flatness values before and after being clamped by the vacuum disk (step S4). According to Table 1, it is known that the surface shape is convex The flatness of the mask substrates A to c after clamping is the same as or slightly better than before clamping, but the surface shape is a concave and saddle-shaped mask base. The flatness of D to G is deteriorated after being clamped. 2. In addition, regarding the mask substrate with a surface shape of a fish plate type, the arrangement direction of the mask substrate on the mask stage is arranged in a specific direction for clamping. The direction (mask substrates Η, I), and the direction orthogonal to the specific direction, that is, the direction of rotating the lens by 90 degrees, and change and hold the mask substrate (mask substrates J, KK) The results are shown in Table 1. It can be seen that the flatness after the vacuum chuck of the fish plate type photomask substrate Η ~ κ is due to the arrangement of the clamped photomask substrate: and: That is, it can be known that the flatness after the vacuum chuck of the fish plate type photomask substrate Η ~ κ will also change due to the position of the photomask substrate after the vacuum chuck. Specifically, such as the photomask substrate Η, Normally, if the arrangement direction of the mask substrate on the mask stage is arranged in a specific direction for the chuck, the curved edge of the fish plate type will touch the chuck of the mask stage of the exposure device, which is flat. degree

O: \ 100 \ 100107.DOC -13 · 200523668 It is almost impossible to improve the 'but other-side' If the photomask substrate J, κ is arranged in the direction of 90 degrees, the arc edge of the fish plate will not be When it touches the central plate of the mask stage of the exposure device, the flatness will be less than ㈢㈣, and the flatness has been improved (Table 1). In addition, the mask substrates of other surface shapes are not shown in Table 1. It is because it is understood that even if it is rotated, the flatness cannot be improved. Secondly, as described above, the types and flatness values of the surface shape before and after the vacuum chuck is held by ㈣ include the reticle substrate A In the photomask substrate group of ~ K, a photomask substrate having an appropriate flatness and a photomask substrate having the same type of surface shape are prepared separately from the U-piece photomask substrates A to κ (step S5). Here, For the separately prepared photomask substrate, the field cooperation description of selecting the same shape as the photomask substrate J. In addition, the photomask substrates A to K and the photomask substrate prepared separately above are controlled in terms of the flatness of the pattern forming area. Formed within specific specifications, but the surface The difference in shape is caused by dispersion. Then, a protective film is coated on the separately prepared photomask substrate. After that, the manufacturing process of the exposure photomask, which is well-known, is continued. That is, the photomask substrate is mounted by an electronic wire riding device. The protective film on the top is patterned as desired. Next, the protective film is developed to form a protective film pattern. Next, the protective film pattern is used as a photomask, and the last name of the photomask substrate is engraved by a reactive ion etching device. Then, the light-shielding body pattern is formed. Then, the protective film pattern is peeled off, and the surface of the photomask substrate is cleaned to form an exposure photomask that forms a desired photomask pattern (step S6). The above-mentioned desired pattern includes a circuit pattern or Contains circuit patterns and patterns for alignment. O: \ 100 \ 100107.doc -14- 200523668 The exposure mask thus obtained was set in an ArF wafer exposure device, and the flatness of the main surface was measured. It was confirmed that 0 · A good value of 2 Mm. Then, if an exposure mask with such a high flatness is used to be clamped on a mask stage of an exposure device, then the above-mentioned exposure mask is illuminated by an illumination optical system In the exposure method in which the above pattern is formed on a desired substrate by a projection optical system, the focus tolerance during wafer exposure will be significantly increased and the productivity of semiconductor products such as DRAM will be greatly improved. According to the embodiment, an effective method for manufacturing an exposure mask can be realized, which can solve the problem of product productivity caused by the flatness of the main surface of the mask substrate being deteriorated after the mask substrate is clamped on the mask stage of the wafer exposure device. Reduced problems. The alignment marks for the photomask substrates A ~ K and the photomask substrates prepared separately above can also be formed in advance. The means for holding the photomask substrate on the photomask stage is not limited to a vacuum chuck. (Second Embodiment) In the first embodiment, the surface shape and flatness are obtained only for the first area 1 of the main surface of the mask substrate 1 shown in FIG. 2 (step S1), but in this embodiment, The surface shape and flatness are obtained for two regions of the first region 1 and the second region 2 surrounding the first region 1. Here, the first area 1 is a center area of the mask substrate, and is a rectangular shape with a side length of 142 mm, and the second area 2 surrounds the first area 1 and has a side length of 15 °. Mouth-shaped area of the mm (from the area of the rectangular opening > shape, the area with the smaller rectangular area centered on the center of the rectangular area as the area is excluded). By setting the photomask substrate 1 O: \ 100 \ 100J07.DOC -15- 200523668 to the vacuum chuck when it is set on the photomask stage of the exposure device, the area to be clamped (the photomask clamping area) is almost included in the first 2 area 2. That is, in the second area 2, almost all the force for holding the photomask substrate on the photomask stage is effective. In the extension line of the conventional technology, not only the pattern formation area but also the flatness of the mask holding area is considered to be expanded to the first area 1 to manage the flatness of the area including the mask holding area. However, in the current mask manufacturing technology, it is very difficult to flatten the entire main surface of the mask substrate 1. The current situation is that the flatness of the main surface of the mask substrate 1 deteriorates sharply at the edges. 1 area 1, the flatness of the center portion of the mask substrate 1 is acceptable, but the flatness of the edge portion of the mask substrate 丨 is deteriorated, so the flatness of the entire main surface of the mask substrate i will be reduced. The measurement results. Therefore, in this embodiment, as described above, the surface shape and flatness are obtained for the two regions including the first region 1 including the mask center and the second region 2 surrounding the i-th region. A substrate flatness measuring device (manufactured by NI Corporation) was used to measure the flatness and surface shape of the main surface of a photomask substrate formed by forming a light-shielding body on a quartz substrate having an angle of 1 52 mm and a thickness of approximately 6 mm. The flatness and surface shape of the region 1 and the flatness and surface shape of the second region 2 are prepared with reticle mask substrates A to M, respectively. Next, the 13 mask substrates A to M were sequentially installed in an ArF wafer exposure apparatus (manufactured by Nikon Corporation), and the flatness of the main surface of each mask substrate after being clamped by a vacuum chuck was measured. Next, a pair of O: \ 100 \ 100107.DOC -16- is produced regarding the types of surface shapes of the 13 photomask substrates A ~ M and the values of the flatness of the first and second areas before and after being clamped by the vacuum chuck. 200523668

Should be related. The results are shown in Table 2. [Table 2] 1st area (before clamping) 2nd area (before clamping) 1st area (after clamping) Photomask substrate flatness (μιη) Surface shape flatness (/ xm) Surface shape flatness ( μπι) A 0.3 convex 4 convex 0.3 B 0.3 convex 3 concave 1.5 C 0.35 convex 4 fish plate 0.6 D 0.35 convex 4 fish plate (90 degree rotation) 0.3 E 0.35 convex 4 saddle 1.0 F 0.35 concave 4 convex 0.3 G 0.35 concave 4 convex 0.8 Η 0.35 concave 4 fish plate 0.8 I 0.35 concave 4 fish plate (90 degree rotation) 0.4 J 0.35 concave 4 saddle 0.9 K 0.5 saddle 3 saddle 1.0 L 0.5 fish plate 3 fish plate 0.9 MU 0.4 fish plate 3 fish plate (90 degrees Rotation) The surface shapes of the first and second regions of 0.4 1 to 3 mask substrates are classified into four types: convex, concave, saddle, and fish plate. The surface shapes of the first and second regions of the mask substrate A having a simple convex shape are all convex. On the other hand, the surface shape of the photomask substrate B, such as a hat with a brim, is convex in the first region and concave in the second region. It is known from Table 2 that the planar shape of the first area due to clamping by the vacuum chuck is O: \ 100 \ 100107.DOC -17- 200523668 'The photomask substrate has a concave shape and a saddle shape in the surface shape of the second area By. In addition, the mask substrates C, D, η, B, L, and M whose surface shape is a fish plate type show different results due to different arrangement directions of the mask substrates on the mask stage. Specifically, if the arrangement direction of the reticle substrate on the reticle stage is arranged in the opposite direction, the chuck, and the specific direction, the radian edge of the fish plate type will touch the chuck of the reticle stage of the exposure device, and will be reduced. Flat I, but # is arranged in the direction of rotating 90 degrees, the radian edge of the fish plate type will not touch the chuck of the mask stage of the exposure device, and the flatness becomes below 〇4, you can confirm The flatness of almost all the mask substrates arranged in this direction (by rotating it by 90 degrees) is improved. In addition, it can be confirmed that the flatness of the first region after clamping by the vacuum chuck is almost independent of the surface shape of the first region before clamping. That is, the shape change of the main surface of the mask substrate before and after being clamped by the vacuum chuck is almost determined by the surface shape of the second region. In addition, when comparing the flatness of the second area with the flatness of the first area, although the value is exceptionally poor, it can be confirmed that when the surface shape of the second area is convex, it is held by a vacuum chuck. The surface shape of the first region of the photomask substrate hardly changed. From the above, the types of the surface shapes of the first region 1 and the second region 2 are prepared for a plurality of photomask substrates, and the values correspond to the flatness values of the main surface of the photomask substrate before and after being clamped by the vacuum chuck. In order to manage the mask chuck area, it is not necessary to expand it to more than necessary. The flatness of the first area 1 does not need to be more severe than necessary. It can use realistic values. Also, consider the second O: \ 100 \ 100107.DOC -18 · 200523668 The surface shape of area 2 can be used to select a mask substrate with less change in flatness on the main surface of the mask substrate before and after clamping by the vacuum chuck. Next, as described above, the types of surface shapes of the first region 1 and the second region 2 before and after being clamped by the vacuum chuck are known in advance, and 13 mask substrates are included in the value of the flatness of the main surface of the mask substrate after clamping. In the photomask substrate group a to M, a photomask substrate having an appropriate flatness and a photomask substrate having the same surface shape are prepared separately from the 13 photomask substrates a to M. • Here, the separately prepared photomask substrate is prepared to have the same surface shape as the photomask substrate F (the first region is concave and the second region is convex). After the photomask substrate was measured, the flatness of the first area was less than or equal to 03 μm, and the flatness of the second area was less than or equal to 4 / xm. Next, a protective film is applied on the photomask substrate. After that, the manufacturing process of the exposure mask of the conventional manufacturing method is continued. That is, a desired pattern is drawn by a protective film on a photomask substrate by an electronic wire drawing device. Next, the protective film is developed to form a protective film pattern. Secondly, the protective film pattern is used as a photomask to etch the mask substrate light-shielding body by a reactive ion etching device to form a light-shielding body pattern. Then, the protective film pattern is peeled off, and then the surface of the mask substrate is cleaned to complete the exposure mask which forms a desired mask pattern. The desired pattern mentioned above includes a circuit pattern, or a circuit pattern and a pattern for alignment. When the exposure mask thus obtained was set in an ArF wafer exposure apparatus and the flatness of the first region was measured, a good flatness of 0.2 μm was confirmed. Then, by forming such a high-flatness exposure mask on the mask stage of the exposure device, an illumination optical system is used to illuminate the above-mentioned exposure mask.

O: \ J00 \ I00107.DOC -19- 200523668 The pattern 'uses an exposure method in which an image of the above pattern is formed by a projection optical system on a desired substrate (for example, a substrate coated with a protective film), and the wafer is exposed The focus tolerance will increase in time, and the productivity of semiconductor products such as dram will be greatly improved. In this way, this embodiment is also the same as the first embodiment, and can provide a method for manufacturing an exposure mask, which can effectively solve the flatness of the main surface of the mask substrate after the mask substrate is clamped on the mask stage of the wafer exposure device. Decrease in product productivity caused by deterioration. The reticle substrates A to M and the reticle substrates separately prepared above may be formed with alignment marks. The method of holding the mask substrate on the mask stage is not limited to a vacuum chuck. In addition, it is known from Table 2 that if the surface shape of the second region is convex, the flatness of the first region after being clamped by the vacuum chuck is good, so the surface shape of the second region can also be used to make the convex shape. A method of using a photomask substrate or an exposure photomask. In the second area, the surface shape, that is, a convex mask substrate or exposure mask having the surface shape as described above, for example, in the edge area of the quartz substrate or an area (central area) more inward than the quartz substrate, a part of the central area may be Obtained by using a rapid grinding rate. Specifically, it can be obtained by polishing the main surface of the quartz substrate in a longer time than before by using a polishing apparatus. Thereafter, a mask substrate is formed by a conventional method to obtain a mask substrate, and an exposure mask can be obtained by patterning the mask. ★ Then, the exposure mask forming the second area having such a specific surface shape (here, convex) is clamped on the mask stage of the exposure device, and is illuminated by 〇: \ 1〇0 \ 1〇〇 1〇7d〇 (: -20- 200523668) The pattern formed on the exposure mask is illuminated by a bright optical system, and the pattern is formed on a desired substrate (for example, a substrate coated with a protective film) by a projection optical system. The exposure method of image imaging is the same as that of the first embodiment, and the focus tolerance during wafer exposure will be significantly increased, which will greatly increase the productivity of semiconductor products such as DRAM. In addition, in the past, the entire main surface was made as much as possible. It will flatten and polish the central substrate of the stone. Therefore, in order not to make a significant difference in the polishing ratio, the length of the polishing time is not controlled deliberately. Therefore, even if the surface shape of the second region becomes convex or concave due to the dispersion of polishing, the degree It is also significantly smaller than the mask substrate and the exposure mask of this embodiment. (Third embodiment) In this embodiment, simulation is used to obtain the equivalent of the mask substrate after being held by a vacuum chuck. Surface shape of the main surface The surface shape of the main surface of the mask substrate. First, the flatness of the pattern forming area (the first area in FIG. 2 (a)) is measured by a substrate flatness measuring device (manufactured by NI Corporation). The surface shape and flatness of the main surface of the photomask substrate formed by forming a light-shielding body on a quartz substrate with a thickness of about 6 mm at a claw angle of 152㈤ were obtained, and 13 photomask substrates having different surface shapes and flatness were prepared. A ~ M. Secondly, "the mask chuck structure of the ArF wafer exposure apparatus (manufactured by Nikon Corporation), and the flatness of the above-mentioned measured flatness of the main surfaces of the 13 mask substrates a to M" are used by the finite element method, The flatness of the main surface of the photomask substrates A to M when the three photomask substrates A to M are sequentially held by the vacuum chuck on the photomask stage of the Arp wafer exposure device is simulated. Use the analytical method to replace O: \ 100M00107.DOC -21-200523668 instead of the limited 7L element method. Next, to confirm whether the simulation is correct, the 13 reticle substrates A described above are actually held in order by a vacuum chuck. M in the above-mentioned ArF wafer exposure device ' The flatness of the main surface of each photomask substrate after the central holding. As a result, the flatness of the main surface of the photomask substrates A to M obtained by the simulation is as flat as the substrate actually set on the ArF wafer exposure device. The degree of flatness of the main surface of the photomask substrates a to m obtained by the degree measuring device is shown in Table 3. It can be confirmed that among the photomask substrates a to m, almost all of the photomask substrates are only 0.1 μm or less. [Table 3]

Photomask substrate Measurement data of the main surface of the photomask substrate

Β 0.3 convex 1.5 1.5

0.8

Η 0.35 I 0.35 concave 0.5 0.8 04 J 0.35 concave 0.9 0.9 Κ 0.5 1.3 1.0

O: \ 100 \ 100107.DOC -22- 200523668 That is, 'for the photomask substrate, when the corresponding relationship between the type of surface shape in the previous embodiment and the value of the flatness before and after clamping by the vacuum chuck is made, The value of the flatness before and after clamping by the vacuum chuck is replaced with the value obtained by simulation. From this result, the flatness of the pattern formation area (the first area in FIG. 2 (a) 丨) was measured by a substrate flatness measuring device (manufactured by NI Corporation), and the surface shape of the main surface of the photomask substrate was determined. The structure of the mask chuck of the exposure device and the flatness of the main surface of the mask substrate that has been obtained, and the master of the mask substrate when the vacuum chuck sequentially clamps the mask substrate to the mask stage of the exposure device The surface shape of the surface can predict the surface shape of the main surface of the mask substrate when the mask substrate is actually set in a wafer exposure apparatus. Therefore, it is possible to manage the surface shape and flatness of the main surface of the photomask substrate with higher precision. Fig. 4 is a flowchart showing a method for manufacturing an exposure mask according to a third embodiment of the present invention. In the flowchart of FIG. 4, in step S3, the surface shape of the main surface of the mask substrate when the mask substrate is clamped by the vacuum chuck is obtained by simulation. Then, in step S4, the correspondence between the surface shape, the flatness obtained using the substrate flatness measuring device, and the flatness obtained using the simulation is made. The steps S1, S2, S5, and S6 are the same as the flowchart in FIG. Next, in step S5, the following photomask substrates are prepared separately from the above-mentioned 13 photomask substrates A to M: the surface shape of the main surface of the substrate is measured by a substrate flatness measuring device, and the photomask substrate is sequentially clamped by a vacuum chuck Light held by exposure device

O: \ 100 \ 100107.DOC -23- 200523668 The shape of the surface of the main surface of the light I substrate of the mask day $ is changed to a flatness of u μη by simulation. After that, the manufacturing process of the exposure mask of the conventional manufacturing method is continued at step S6. That is, a desired pattern is drawn by a protective film on a photomask substrate by an electronic line-drawing device. Next, the protective film is developed to form a protective film pattern. 'Secondly, the protective film is used as a photomask, and then the photomask-based body is protected by a reactive ion money engraving device, and a light-shielding pattern (light Hood pattern). After that, the protective film pattern is peeled off, and then the surface of the mask substrate is cleaned to complete the exposure mask for forming a desired mask pattern. When this exposure mask was actually set in an ArF wafer exposure device and the surface shape and flatness of the main surface were measured using a substrate flatness measuring device, it was confirmed that a good flatness as G. 2 / m was obtained. Then, if an exposure mask with such a high flatness is clamped on the mask stage of the exposure device, and then the pattern formed on the exposure mask is illuminated by the illumination optical system, and the projection optical system is used to An exposure method for imaging the above pattern on a desired substrate (for example, a substrate coated with a protective film) will increase the focus tolerance during wafer exposure, and greatly increase the productivity of semiconductor products such as DRAM. In this way, this embodiment is also the same as the first and second embodiments, and an effective method for manufacturing an exposure mask can be realized, which can solve the problem after the mask substrate is clamped on the mask stage of the wafer exposure device. The problem that the flatness of the main surface of the cover substrate deteriorates causes a decrease in product productivity. The reticle substrates A to M and the reticle substrates separately prepared above may be formed in advance with alignment marks. The means for holding the photomask substrate on the photomask table is not limited to a vacuum chuck. O: \ 100 \ 100107.DOC -24- 200523668 In each of the above-mentioned embodiments, for example, the wafer exposure apparatus may not be an ArF wafer exposure apparatus. In addition, after the mask pattern is formed, the flatness of the main surface of the mask substrate can be further measured, and the measurement data can be used to simulate and obtain the surface shape of the main surface of the mask substrate when the mask substrate is set in the exposure device. Therefore, since the deformation of the main surface of the mask substrate when the mask pattern is formed is also considered in the results obtained by simulation, the surface shape and flatness of the main surface of the mask substrate can be more accurately determined. management. In addition, the photomask is not limited to those for ArF or KRF, and can be applied to, for example, a reflective photomask for vacuum ultraviolet exposure, a photomask for X-ray exposure, and a photomask for electron beam exposure. (Fourth Embodiment) In this embodiment, the surface shape of the main surface of the mask substrate corresponding to the surface shape of the main surface of the mask substrate after being clamped by the vacuum chuck is obtained by simulation. Fig. 5 is a flowchart showing a method for manufacturing an exposure mask according to this embodiment. In step si, the flatness of the pattern formation area (the i-th area 0 in FIG. 2⑷) is measured by a substrate flatness measuring device (manufactured by NI Corporation), and then formed on a quartz substrate having an angle of 152 mm and a thickness of about 6 mm. The surface shape and flatness of the main surface of the photomask substrate formed by the light-shielding body. Next, in step S2, the photomask chuck structure of the ArF wafer exposure device (manufactured by Nikon Corporation) and the above-mentioned photomask substrate main The measured flatness of the above surface is obtained by using a finite element method and a simulation to obtain the light when the above-mentioned one photomask substrate is sequentially held on the photomask stage of the ArF wafer exposure device by a vacuum chuck. O: \ IOO \ IOOI07.DOC -25- 200523668 The flatness of the main surface of the mask substrate. An analytical method may be used instead of the finite element method. Then, in step S3, the flatness of the main surface of the mask substrate obtained by simulation is judged. If the degree is suitable for its specifications, if it is judged that it is suitable for its specifications, it enters the manufacturing process of the exposure mask in step S4. On the other hand, when it is judged in step S3 that the flatness of the aforementioned mask substrate is not suitable for its specifications, Strip at step 85 The light-shielding film on the quartz substrate of the photomask substrate described above. Next, the surface of the quartz substrate is polished in step 86. Next, the light-shielding film is re-formed on the polished surface of the quartz substrate in step S7, and the measurement is returned to step s1. Flatness. This embodiment is also the same as the first embodiment, the second embodiment, and the third embodiment, and can realize an effective method for manufacturing an exposure mask, which can solve the problem of clamping a mask substrate to a wafer exposure apparatus. After the photomask stage, the flatness of the main surface of the photomask substrate is deteriorated, resulting in a decrease in the productivity of the product. In addition, the above-mentioned photomask substrate can also be formed with an alignment mark. In addition, the photomask substrate is held on the photomask stage. The means are not limited to a vacuum chuck.

In addition, for example, the wafer exposure apparatus may be an ArF wafer exposure apparatus. In addition, 'the flatness of the main surface of the mask substrate can be measured again after the mask pattern is formed', and the measurement data can be used to simulate and obtain the surface shape of the main surface of the mask substrate when the mask substrate is set in the exposure device. As a result, the deformation of the main surface of the mask substrate when the mask pattern is formed will also be considered in the results obtained by simulation. Therefore, the surface shape and flatness of the main surface of the mask substrate can be performed with higher accuracy. management. In addition, the photomask is not limited to those used for ArF or KRF. It can also be applied to, for example, reflective photomasks for vacuum ultraviolet exposure, XQ: \ 100 \ I00107.DOC -26- 200523668 photomasks for light exposure, and electronic wires. Exposure mask, etc. (Fifth Embodiment) Next, a method for generating substrate information in the fifth embodiment of the present invention will be described. The method for generating the mask substrate information in this embodiment includes: for each of the 11 mask substrates A to K of the watchmaker, in accordance with the process of FIG. I, for example, steps S1 to S3, obtaining the surface shape and clamping of the main surface • Process for flatness of the front and back main surfaces; and a process for producing the correspondence relationship between the types of the photomask substrate and the surface shape and the flatness value as shown in Table 1 with respect to the 11 photomask substrates A to K; and Corresponds to the process stored in a computer (PC). The above correspondence stored in a computer (PC) or the like may be displayed. Specifically, for example, a sticker on which a display content is printed may be affixed to a container containing the u mask substrates A to κ. By adopting such a display method for the above correspondence, it is easy to manage and solve the problem that the productivity of the product is reduced due to the deterioration of the flatness of the photomask substrate and the main surface of the photomask after the photomask substrate is held on the photomask stage of the wafer exposure device. Photomask substrate. In addition, after step S2 in the flowchart of FIG. 1, information that the surface shape of the main surface is convex is displayed in the information obtained in step S2 of the flowchart of FIG. J, and the corresponding mask substrate is displayed. Correspond, and the correspondence is stored in a computer (PC), etc., and another mask substrate information generation method different from the mask substrate information generation method of this embodiment can be performed. At this time, it is also the same as the method of generating the mask substrate information in this embodiment, and for this correspondence, the display of the mask substrate can also be easily managed by the display of a sticker or the like. O: \ 100 \ 100107.DOC -27- 200523668 Here, 11 photomask substrates A ~ κ in Table 1 are taken as an example to explain the method of generating information about the photomask substrate, but for the 13 photomask substrates A in Table 2 ~ M can also generate the same mask substrate information. (Sixth Embodiment) Fig. 6 is a schematic diagram showing a server system according to a sixth embodiment of the present invention. In the fifth embodiment, a sticker is used as an example for display. However, in this embodiment, it is displayed on a server. Therefore, the method for generating a thin film of the mask substrate in this embodiment can be used for e-commerce (e-mail business ). First, for example, a table 袼, table 2 or table 32 corresponding to a table 制作, a table 2 or a table 32 is produced at the production place, and a web page containing the table as information is stored in the server 12. The server 12 is a memory means for memorizing the hardware and the like of the web page. The server 12 is connected to most customers (customer device port 3) via the Internet. A dedicated route can be used instead of the Internet. A combination of the Internet and a dedicated line can also be used. The server 12 is equipped with There are: conventional means for receiving the processing of the above-mentioned webpage request message from the customer 13; conventional means for processing the transmitting of the above-mentioned webpage in a form that can be displayed on the client side; The conventional hand of processing the application information of the substrate mask ## 4 The white-known means is composed of, for example, a LAN card, a memory device, server software, a CPU, etc., and performs the desired processing in coordination. If the server 12 receives When the request message from the customer 13 for the above webpage is transmitted, the information necessary for the daytime display 14 shown in FIG. 3 to be displayed on the display 2 of the customer 13 is transmitted to the customer 13. The daytime display 14 shows: 1 Forms of what is not 15 Select the desired substrate mask and confirm

O: \ 100 \ 100107.DOC -28 * 200523668 confirmed confirmation box 16 and the decision to transfer the main purpose of the substrate mask confirmed in the purchase confirmation box to the server 12 decision image symbol (ic〇n) 17 . In FIG. 6, for the sake of simplicity, although Form 15 having the contents shown in Table 1 is shown, a form having the contents shown in Table 2 or the contents shown in Table 3 may be used. According to this embodiment, since a photomask substrate having a high flatness behind a photomask holding the photomask substrate on a wafer exposure device can be purchased, a server can be realized, which can effectively solve the problem of holding the photomask substrate on the wafer exposure device. Of the photomask stage • The flatness of the main surface of the rear photomask substrate is deteriorated, resulting in a decrease in product productivity. As mentioned above, although the embodiment of this invention was described, this invention is not limited to this embodiment. For example, in the above embodiment, a convex-shaped mask substrate can obtain good results, but there may be cases where a concave-shaped mask substrate can obtain good results due to the exposure device provided with the mask substrate. That is, because the flatness of the mask substrate after the vacuum chuck is greatly influenced by the shape matching of the mask chuck table and the chuck chuck surface, the light that should be selected according to the use of the chuck table The shape of the main face of the mask will change. In addition, in the above embodiments, the case of the photomask substrate for the Arp wafer exposure device is described, but it can also be used for other photomask substrates, such as the photomask substrate for the KrF wafer exposure device and vacuum ultraviolet exposure. Used reflective mask substrates, mask substrates for X-ray exposure, mask substrates for electron beam exposure, and the like. In addition, various embodiments of the invention are included in the above-mentioned embodiments, and various inventions can be extracted from appropriate combinations of the disclosed plural constituent elements. For example, even if all the constituent elements shown in the embodiment are O: \ 100 \ 100107.DOC -29-200523668, a few constituent elements are deleted and the problem described in the section of the problem to be solved by the invention can be solved. In this case, it is possible to extract the structure in which the constituent elements have been deleted as an invention. In addition, various modifications can be made without departing from the scope of the present invention. [Effects of the Invention] As described above, according to the present invention, it is possible to realize an effective exposure mask manufacturing method, a mask substrate information generation method, a semiconductor device manufacturing method, a mask substrate, an exposure mask, and a server. It can effectively solve the problem that the productivity of the product caused by the flatness of the main surface of the photomask substrate is deteriorated after the photomask substrate is clamped on the photomask stage of the wafer #light device. [Brief description of the drawings] [Fig. 1] Fig. 1 is a flowchart showing a manufacturing method of an exposure mask according to a first embodiment of the present invention. [Fig. 2] Fig. 2 (a) is a plan view of the main surface of the photomask substrate, that is, a diagram for explaining the first and second regions; Fig. 2 (b) is a photo of the first region of the photomask substrate. Figure, which is a cross-sectional view of the first area 1; Figure 2 (c) is a diagram illustrating the first area 1 of the photomask substrate, that is, other cross-sectional views of the first area 丨; Figure 2 (sentence is The pattern of the second region 2 of the photomask substrate, that is, the cross-sectional view of the second region 2. [FIG. 3] FIG. 3 (a) is a diagram illustrating the first region 1 of the photomask substrate, that is, the first 1 is a schematic perspective view of area 1; FIG. 3 (b) is a diagram illustrating the first area O.MOOMOOJ07.DOC -30- 200523668 of the photomask substrate, that is, other perspective views of area 1; FIG. 3 (c ) Is a diagram illustrating the first region 1 of the photomask substrate, that is, other schematic perspective views of the first region 1; FIG. 3 (d) is a diagram illustrating the first region 1 of the photomask substrate, that is, Other schematic perspective views of the first area 1. [FIG. 4] FIG. 4 is a flowchart showing a method of manufacturing an exposure mask according to a third embodiment of the present invention. [FIG. 5] FIG. 5 is a view showing the method of the present invention. 4th [Fig. 6] Fig. 6 is a schematic diagram showing a server pattern related to the sixth embodiment of the present invention. [Description of symbols of main components] 1 ...... Section 1 Area 2 ...... 2nd area 11 .... Production area 12 .... Server 13 .... Customer 14 ......... Screen 15 .... Form 16____ Confirmation box 17 ... Image symbol O: \ 100 \ 100107.DOC -31-

Claims (1)

200523668 10. Scope of patent application: 1. A flatness simulation system for a photomask substrate, comprising: a method for measuring flatness of a substrate for obtaining the first information on the flatness of the main surface of the photomask substrate; Information related to the mask holding structure of the exposure device is used to obtain the second information of the flatness of the main surface obtained by simulation when the photomask substrate is mounted on the exposure device. 2. The flatness simulation system of the photomask substrate according to claim 1, wherein a registration mark is formed on the photomask substrate in advance. 3. The flatness simulation system of the photomask substrate according to claim 1, wherein the second information obtained by the simulation above is obtained by using a finite element method. 4. The flatness simulation system of the photomask substrate according to the item 1 or 3, which includes information about the flatness of the main surface of the photomask substrate obtained in front of the photomask stage of the exposure device, and The information about the flatness obtained by the above-mentioned simulation, and a means of making corresponding relationships. 5. The flatness simulation system of the photomask substrate according to the item 1 or 3, which includes a means for judging whether the flatness of the photomask substrate obtained by the simulation meets the specifications. 6. The flatness simulation system of the photomask substrate according to claim 1, wherein the flatness is the surface shape, flatness, or any one of the surface shape and flatness 0 0 :, 100 \ _07.DOC