JP5411648B2 - Mask blank substrate manufacturing method, mask blank substrate manufacturing apparatus, mask blank manufacturing method, and transfer mask manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a mask blank substrate, a mask blank substrate manufacturing apparatus, a mask blank manufacturing method, and a transfer mask manufacturing method, which are used for manufacturing a transfer mask that is an original circuit pattern of a semiconductor circuit. Regarding the method.

  Conventionally, in the manufacture of a mask blank substrate, both main surfaces of a mask blank substrate (hereinafter sometimes simply referred to as “substrate”) are first roughly ground (lapped), and then a plurality of times while changing polishing conditions. Polish over. For grinding the mask blank substrate, a grinding apparatus shown in FIG. 9 is usually used. The conventional grinding apparatus includes an upper surface plate 10 having a metal grinding surface 11, a lower surface plate 20 having a metal grinding surface 21, an internal gear 22 integrated with the lower surface plate 20, and a lower surface plate 20. And a carrier 30 provided with a plurality of substrate housing holes 31. In addition, the lower surface plate 20 and the grinding surface 21 may be integrated, and may be comprised so that it may mutually independently rotate via a bearing.

  FIG. 10 shows a plan view of the carrier 30. As shown in FIG. 10, the outer shape of the carrier 30 is an external gear, and a plurality of substrate accommodation holes 31 having the same shape as the substrate 40 and slightly larger than the substrate 40 are provided in the main surface thereof. Further, the carrier 30 is made of a resin having low hardness so that the substrate 40 is not damaged even if it contacts the substrate 40. Further, since the substrate 40 is ground by being brought into contact with the grinding surface 11 and the grinding surface 21 while being accommodated in the substrate accommodation hole 31, the carrier 30 is less than the substrate 40 so as not to hinder the grinding of the substrate 40. It is also made thin.

  When grinding the substrate 40 using a conventional grinding apparatus, first, a plurality of carriers 30 are arranged on the grinding surface 21 so that gears provided on the outer periphery thereof mesh with the internal gear 22 and the sun gear 23. Next, the substrate 40 is accommodated in the plurality of substrate accommodation holes 31 of each carrier 30. Next, the upper surface plate 10 is lowered while facing the lower surface plate 20, and the ground surface 11 and the ground surface 21 are brought into contact with both main surfaces (surfaces to be ground) of the substrate 40. Next, with the substrate 40 sandwiched between the grinding surface 11 and the grinding surface 21, the upper surface plate 10, the lower surface plate 20, and the sun gear 23 are each rotated at a predetermined speed. In this way, the carrier 30 meshes with the internal gear 22 and the sun gear 23 between the grinding surface 11 and the grinding surface 21, and obtains power from the rotation of the internal gear 22 and the sun gear 23 to rotate the sun gear 23 while rotating. It performs a so-called planetary motion that revolves around the center. At this time, by supplying a grinding liquid (slurry) containing silicon carbide (SiC) fine particles between the ground surfaces of the substrate 40 and the ground surface 11 and the ground surface 21, these fine particles are separated from the free abrasive grains. And both ground surfaces of the substrate 40 are ground simultaneously. In addition, by changing the rotational speed of the lower surface plate 20 (internal gear 22) and the rotational speed of the sun gear 23, the revolution speed of the carrier 30 centering on the sun gear 23 and the rotation speed of the carrier 30 are adjusted. be able to. Further, as shown in FIG. 9, the rotation direction of the upper surface plate 10 is normally set in the direction opposite to the rotation direction of the lower surface plate 20. This is because the relative speed between the ground surface of the substrate 40 and the grinding surface 11 can be increased by rotating the upper surface plate 10 in the opposite direction to the lower surface plate 20, so that the amount of grinding of the substrate 40 per unit time can be increased. Because.

However, when the substrate 40 is ground, the ground surface 11 and the ground surface 21 are simultaneously scraped and worn by the loose abrasive grains in the grinding liquid and the grinding scraps separated from the surface to be ground of the substrate 40. Therefore, in the conventional grinding apparatus, as the number of processed substrates 40 increases, the flatness of the grinding surface 11 and the grinding surface 21 deteriorates, or the undulations occur on the surfaces of the grinding surface 11 and the grinding surface 21. . As a result, in the conventional grinding apparatus, as the number of substrates 40 processed increases, the grinding amount of the substrate 40 per unit time decreases, or the desired flatness can be obtained even if the substrate 40 is ground to a predetermined thickness. There was a problem that could not be. In order to solve such a problem, a technique described in Patent Document 1 has been developed.

JP 2008-254166 A

  However, the technique described in Patent Document 1 is a carrier used for grinding after performing a grinding process of grinding a main surface of a glass substrate using a surface plate in which fixed abrasive grains including diamond particles are arranged on a grinding surface. And the glass correction ring are replaced, and the same processing as the grinding step is performed to remove the waviness of the ground surface of the surface plate and correct the flatness. In other words, the technique described in Patent Document 1 is a technique for correcting the flatness of the ground surface of the surface plate after it has deteriorated, and is not a technique for suppressing the deterioration of the flatness of the ground surface itself. In addition, the technique described in Patent Document 1 requires a lot of time each time to correct the flatness of the ground surface of the surface plate. Therefore, when the technique described in Patent Document 1 is used in industrial production, it is necessary to frequently perform correction work that requires a lot of time, and thus the production capacity of the conventional grinding apparatus is significantly reduced.

  Therefore, the present inventors find out the mechanism and factors of the deterioration of the flatness of the conventional grinding apparatus by examining in detail the process in which the flatness of the grinding surface 11 and the grinding surface 21 deteriorates. It came to. That is, the inventors of the present invention grinding the substrate 40 while the grinding surface 11 and the grinding surface 21 perform circular motion causes undulations and the like on the surfaces of the grinding surface 11 and the grinding surface 21 and deteriorates the flatness thereof. It came to the conclusion that it is the main factor to make it.

  Specifically, it is as follows. If the substrate 40 is ground while the grinding surface 11 and the grinding surface 21 perform a circular motion, the linear velocity increases as the distance from the center of rotation of the grinding surface 11 and the grinding surface 21 increases, and as the linear velocity increases. The amount of grinding of the substrate 40 per unit time also increases. And if the grinding amount of the board | substrate 40 per unit time increases, the abrasion amount per unit time of the grinding surface 11 and the grinding surface 21 by the loose abrasive grain in a grinding fluid will also increase. In other words, if the substrate 40 is ground while the grinding surface 11 and the grinding surface 21 perform a circular motion, a difference occurs in the amount of wear on the grinding surface 11 and the grinding surface 21 depending on the distance from the rotation center thereof. This difference in the amount of wear causes waviness or the like on the grinding surface 11 and the grinding surface 21 and deteriorates their flatness. And if the board | substrate 40 is ground with the grinding surface 11 and the grinding surface 21 which flatness deteriorated by such a mechanism, the flatness of the board | substrate 40 will deteriorate inevitably.

Furthermore, as a result of continuing intensive studies on the deterioration of the flatness of the substrate 40 after grinding, the present inventors have also found a mechanism and factors that are not caused by the deterioration of the flatness of the grinding surface 11 and the grinding surface 21 described above. I came up with it. That is, the inventors of the present invention perform the planetary movement with the sun gear 23 as the center of revolution while the carrier 30 accommodates the substrate 40 in the substrate accommodation hole 31, which is a factor that deteriorates the flatness of the substrate 40 after grinding. I found out that it was one. That is, if the carrier 30 performs a planetary motion with the sun gear 23 as the center of revolution while the substrate 40 is accommodated in the substrate accommodation hole 31, the carrier 30 is placed on the surface to be ground of the substrate 40 according to the distance from the center of rotation of the carrier 30. A difference in linear velocity due to the rotation of the carrier 30 occurs. Specifically, at the point I of the substrate 40 close to the rotation center of the carrier 30 and the point O of the substrate 40 far from the rotation center of the carrier 30 shown in FIG. 10, the point O is relative to the grinding surface 11 and the grinding surface 21. The relative linear velocity is high. Therefore, if the carrier 30 performs planetary motion with the sun gear 23 as the center of revolution while the substrate 40 is accommodated in the substrate accommodation hole 31, the substrate relative to the grinding surface 11 and the grinding surface 21 as the distance from the center of rotation of the carrier 30 increases. The linear velocity of 40 is increased, and the amount of grinding of the substrate 40 per unit time is increased. As a result, the flatness of the substrate 40 is deteriorated.

  Therefore, the problem to be solved by the present invention is that the flatness of the ground surface is hardly deteriorated, and the substrate grinding method and the grinding apparatus capable of uniformly grinding the entire surface to be ground of the substrate, and the substrate by the grinding method are provided. It is to provide a method for manufacturing a mask blank and a transfer mask.

  In order to solve the above-mentioned problem, the first means includes an upper surface plate including a fixed abrasive portion to which abrasive grains are fixed, a lower surface plate including a fixed abrasive portion to which abrasive particles are fixed, and the upper surface plate. A carrier for holding the substrate in contact with both the fixed abrasive grains of the plate and the lower surface plate, and a mask blank substrate manufacturing apparatus, while the upper surface plate and the lower surface plate are orbitally moved In addition, the entire contact surface with the substrate in the fixed abrasive portion of the upper surface plate and the entire contact surface with the substrate in the fixed abrasive portion of the lower surface plate are applied to each surface to be ground of the substrate. It is a manufacturing method of the mask blank board | substrate characterized by making it contact.

  A second means is a method of manufacturing a mask blank substrate according to the first means, wherein the fixed abrasive part is one in which diamond abrasive grains are fixed.

  The third means is that the orbital motion of the upper surface plate and the orbital motion of the lower surface plate have the same radius of rotation, rotational speed, and rotational direction, and the mask according to the first or second means It is a manufacturing method of the board | substrate for blanks.

  According to a fourth means, the mask blank according to any one of the first to third means, wherein the carrier reciprocates while the upper surface plate and the lower surface plate are orbital. It is a manufacturing method of the board | substrate.

  The fifth means is that the maximum value of the non-contact area that is instantaneously separated from the substrate in the fixed abrasive part of the upper surface plate while the upper surface plate and the lower surface plate are orbitally moving. A non-contact area that is 10% or more of the area of the surface to be ground of the substrate to be ground by the fixed abrasive part of the upper surface plate and is instantaneously separated from the substrate in the fixed abrasive part of the lower surface plate The mask blank according to any one of the first to fourth means is characterized in that the maximum value is 10% or more of the area of the ground surface of the substrate to be ground by the fixed abrasive part of the lower surface plate It is a manufacturing method of the board | substrate.

  When correcting the flatness of the fixed abrasive part, the sixth means includes the contact surface of the fixed abrasive part of the upper surface plate with the substrate and the substrate of the fixed abrasive part of the lower surface plate. A mask blank substrate manufacturing method according to a first means, characterized in that the contact surface is directly brought into contact with and rubbed.

  The seventh means includes a fixed abrasive part to which abrasive grains are fixed, an upper surface plate that performs orbital motion, a lower surface plate that includes a fixed abrasive part to which abrasive particles are fixed and performs orbital motion, and A carrier that holds the substrate in contact with both fixed abrasive parts of the upper surface plate and the lower surface plate, and while the upper surface plate and the lower surface plate are in orbital motion, The mask blank substrate, wherein the entire contact surface with the substrate in the fixed abrasive portion and the entire contact surface with the substrate in the fixed abrasive portion of the lower surface plate are in contact with the substrate, respectively. It is a manufacturing apparatus.

The eighth means is characterized in that the fixed abrasive part of the upper surface plate, the fixed abrasive part of the lower surface plate, and the number of through holes for holding the substrate in the carrier are the same. An apparatus for manufacturing a mask blank substrate according to the means.

  According to a ninth means, in the mask blank substrate according to the seventh or eighth means, the diamond abrasive grains are fixed to the both fixed abrasive grains of the upper and lower surface plates. It is a manufacturing device.

  The tenth means is any one of the seventh to ninth means, wherein the orbital motion of the upper surface plate and the orbital motion of the lower surface plate have the same rotational radius, rotational speed, and rotational direction. It is a manufacturing apparatus of the substrate for mask blanks concerning.

  The eleventh means is the mask blank according to any one of the seventh to tenth aspects, wherein the carrier reciprocates while the upper surface plate and the lower surface plate are orbital. It is the manufacturing apparatus of the board | substrate.

  The twelfth means performs precision polishing on the main surface of the mask blank substrate manufactured by the method for manufacturing a mask blank substrate according to any one of the first to sixth means, and further, a transfer pattern is formed on the main surface. A mask blank manufacturing method is characterized by forming a thin film for formation.

  A thirteenth means is a method for manufacturing a transfer mask, characterized in that a transfer pattern is formed by patterning the thin film in a mask blank manufactured by the mask blank manufacturing method according to the twelfth means.

  According to the present invention, the contact surface with the substrate, that is, the entire ground surface of the fixed abrasive part of the upper surface plate, and the entire ground surface of the lower surface plate are in contact with each surface to be ground of the substrate. Since the entire surface of the ground surface of the surface plate and the entire surface of the ground surface of the lower surface plate are evenly worn, the surface flatness of the ground surface of the upper surface plate and the ground surface of the lower surface plate is unlikely to deteriorate. As a result, according to the present invention, the surface flatness of the substrate after grinding hardly deteriorates even if the number of substrates processed by the same grinding apparatus is increased. Therefore, the ground surface of the upper surface plate and the ground surface of the lower surface plate Since the frequency of the work for correcting the surface flatness can be reduced, the productivity of the substrate grinding apparatus can be increased.

  Further, according to the present invention, since the area of the grinding surface of the upper surface plate and the area of the grinding surface of the lower surface plate are smaller than the area of each surface to be ground of the substrate, the entire grinding surface of the upper surface plate and the surface of the lower surface plate The entire surface of the grinding surface can be reliably brought into contact with each surface to be ground of the substrate.

  In addition, according to the present invention, the number of fixed abrasive grains of the upper surface plate, the number of fixed abrasive grains of the lower surface plate, and the number of through-holes that hold the substrate in the carrier are the same. Can be ground.

  In addition, according to the present invention, since the fixed abrasive part of the upper surface plate and the fixed abrasive part of the lower surface plate are fixed with diamond abrasive grains, the amount of substrate grinding per unit time can be increased. .

  Further, according to the present invention, the orbital motion of the upper surface plate and the orbital motion of the lower surface plate have the same rotation radius, rotational speed, and direction of rotation, so that the upper surface plate and the lower surface plate are in orbital motion. The upper surface plate and the lower surface plate face each other while maintaining a mirror image relationship. As a result, according to the present invention, the force applied to the substrate from above and the force applied from below are always balanced, so that the behavior of the substrate during grinding can be stabilized.

Further, according to the present invention, since the carrier reciprocates while the upper surface plate and the lower surface plate are orbital, the ground surface of the upper surface plate, the ground surface of the lower surface plate, and each surface to be ground of the substrate The relative position changes gradually. As a result, according to the present invention, each ground surface of the substrate is ground in contact with various parts of the ground surface of the upper surface plate and the ground surface of the lower surface plate, so that the ground surface and the lower surface plate of the upper surface plate Surface characteristics such as waviness on the ground surface are difficult to be transferred to each ground surface of the substrate.

  Further, according to the present invention, while the upper surface plate and the lower surface plate are orbital, the maximum non-contact area that is instantaneously separated from the substrate on the ground surface of the upper surface plate and the ground surface of the lower surface plate. Since the value is 10% or more of the area of each ground surface of the substrate, the ground surface of the upper surface plate and the ground surface of the lower surface plate reliably contact the peripheral edge of each ground surface of the substrate. The entire surface to be ground can be evenly ground.

  Further, according to the present invention, since the ground surface of the upper surface plate and the ground surface of the lower surface plate are brought into direct contact and rubbed together, the surface flatness and waviness of the ground surface of the upper surface plate and the ground surface of the lower surface plate are adjusted. It can be corrected in a short time. As a result, according to the present invention, the productivity of the substrate grinding apparatus can be increased.

FIG. 1 is a perspective view showing a configuration of a mask blank substrate grinding apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of the upper surface plate and the configuration in the vicinity thereof according to the AA chain line of FIG. FIG. 3 is a plan view showing the configuration of the carrier. FIG. 4 is a plan view showing the positional relationship between the fixed abrasive part (grinding surface) and the substrate when the substrate is placed on the lower surface plate. FIG. 5 is an explanatory view for explaining the positional relationship between the ground surface of the lower surface plate and the substrate during the orbital motion of the lower surface plate, and (a) is a ground surface of one lower surface plate shown in FIG. 4 and the substrate corresponding thereto. (B) to (e) respectively show the state in which the orbital motion of the lower surface plate has advanced by 45 ° from the state of (a). FIG. 6 is a diagram comparing the average values of the flatness of the substrate main surface of the same batch in each example among the batches. FIG. 7 is a diagram in which the average values of the flatness of the main surface of the same batch in the comparative example are compared between the batches. FIG. 8 is a plan view showing a configuration of a carrier according to another embodiment of the present invention. FIG. 9 is a schematic view showing a configuration of a main part of a conventional mask blank substrate grinding apparatus. FIG. 10 is a plan view showing the configuration of the conventional carrier shown in FIG.

<One Embodiment of the Present Invention>
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

As shown in FIG. 1, a mask blank substrate grinding apparatus 100 according to the present embodiment includes two frames 110 that are skeletons that support the grinding apparatus 100 from above and below, and two frames 110 attached to the two frames 110, respectively. Motor 120, two eccentric connecting portions 130 attached to the two motors 120, upper surface plate 140, diamond sheet 155 which is a fixed abrasive portion attached to upper surface plate 140, carrier 150 for holding the substrate, Lower platen 170, diamond sheet 165 attached to lower platen 170, two slide devices 180 that reciprocate carrier 150 while holding both ends of carrier 150, and two that fix carrier 150 to two slide devices 180, respectively A fixed plate 185 is provided.

  The upper frame 110 is connected to a drive device (not shown), and receives power from the drive device and moves up and down in the vertical direction. If the upper frame 110 moves upward, the motor 120, the eccentric connecting portion 130, and the upper surface plate 140 connected to the upper frame 110 also move upward, so that the carrier 150 and the upper surface plate 140 A large space is formed between the two. Through this formed space, the substrate 160 is accommodated in the substrate accommodation hole 151 of the carrier 150 or taken out from the substrate accommodation hole 151.

  As shown in FIG. 2, the upper motor 120 includes a shaft 121 extending vertically downward, and the shaft 121 is fitted into the center of an eccentric connecting portion 130 disposed directly below the motor 120 and integrated with the eccentric connecting portion 130. It has become. Therefore, the eccentric coupling part 130 also rotates with the rotation of the shaft 121. Further, the eccentric connecting portion 130 includes an eccentric shaft 131 extending vertically downward at a position off the center, and the eccentric shaft 131 is rotatably fitted in a bearing unit 141 attached to the uppermost portion of the upper surface plate 140. It is. The bearing unit 141 is accommodated in a cylindrical portion at the top of the housing 149, and a gap 142 is provided immediately below the bearing unit 141. With such a configuration, the rotational power from the motor 120 is propagated to the upper surface plate 140 via the eccentric connecting portion 130 and the eccentric shaft 131, and the upper surface plate 140 itself is rotated without rotating the upper surface plate 140 itself. It is converted into an orbital motion of the upper surface plate 140 without rotating. The rotational radius of the orbital motion of the upper surface plate 140 is the distance between the shaft centers of the shaft 121 and the eccentric shaft 131, and the rotational speed is the same as the rotational speed of the shaft 121.

  Further, the upper surface plate 140 includes a bearing unit 141, a gap 142, a plurality of vent pipes 143, a plurality of air cylinders 144, a plurality of pressing plates 145, a plurality of surface adjustment units 146, and a sliding contact inside the housing 149. A face plate 147 is provided. On the other hand, the lower surface plate 170 has the same outer shape as the upper surface plate 140 and includes components corresponding to the bearing unit 141, the gap 142, the sliding contact surface plate 147, and the housing 149, but the ventilation pipe 143 and the air cylinder 144 are included. , The pressing plate 145 and the structural member corresponding to the surface adjustment unit 146 are not provided.

  The lower frame 110 has the same configuration as that of the upper frame 110 except that it is not connected to the driving device. Similarly, the lower motor 120 and the eccentric connecting portion 130 are the same as the upper motor 120 and the eccentric connecting portion. The configuration is the same as 130. Therefore, the lower frame 110 is fixed to the installation surface, and the lower surface plate 170 orbits like the upper surface plate 140.

  The same number of diamond sheets 155 as the substrate accommodation holes 151 are attached to the sliding surface plate 147 of the upper surface plate 140 so as to correspond to the positions of the substrate accommodation holes 151 in the carrier 150. Similarly, the same number of diamond sheets 165 as the substrate accommodation holes 151 are attached to the upper surface of the lower surface plate 170 (corresponding to the sliding contact surface plate 147) so as to correspond to the position of the substrate accommodation holes 151 in the carrier 150. Further, as shown in FIG. 2, the diamond sheets 155 and 165 face each other when the upper platen 140 is lowered after the substrate 160 is accommodated in the substrate accommodation hole 151, that is, the same range of the substrate 160 is moved up and down. It is attached to the upper surfaces of the sliding contact surface plate 147 and the lower surface plate 170 so as to be sandwiched from the direction. The diamond sheets 155 and 165 can be easily attached to and detached from the upper surfaces of the slidable contact surface plate 147 and the lower surface plate 170 since the pressure sensitive adhesive is applied to the back surfaces thereof.

Inside the upper surface plate 140, the vent pipe 143 is connected to a compressor (not shown) and supplies compressed air sent from the compressor to the air cylinder 144. When compressed air is supplied from the vent pipe 143, the air cylinder 144 lowers the push-down plate 145 and presses the surface adjustment unit 146 vertically downward. The surface adjustment unit 146 pressed by the air cylinder 144 presses the slidable contact surface plate 147 directly below the surface adjustment unit 146. When pressed by the surface adjustment unit 146, the sliding contact surface plate 147 is bent, and the diamond sheet 155 attached immediately below the sliding contact surface plate 147 is strongly pressed by the substrate 160.

  As shown in FIG. 2, the surface adjustment unit 146 is arranged so that it faces the mounting position of the diamond sheet 155, in other words, the center of the surface adjustment unit 146 and the center of the diamond sheet 155 overlap in the vertical direction. It is fixed to the components inside the surface plate 140. Further, the surface adjustment unit 146 is installed on the upper surface plate 140 directly above all the diamond sheets 155. Further, the ventilation pipe 143, the air cylinder 144, and the pressing plate 145 are also installed immediately above all the surface adjustment units 146 on the upper surface plate 140. When supplying compressed air from the compressor to the plurality of air cylinders 144 installed on the upper surface plate 140, the compressor can supply compressed air to the air cylinders 144 at different pressures. . Therefore, for example, the pressure of the compressed air supplied to the air cylinder 144 at the position where the substrate 160 having a small amount of grinding is measured by measuring all the grinding amounts of the plurality of substrates 160 ground simultaneously by the grinding apparatus 100. Can be selectively enhanced. In this way, the next grinding amount of the substrate 160 at the position where the substrate 160 where the grinding amount was small was arranged can be selectively increased. That is, the grinding apparatus 100 can individually feedback control the grinding amount of the substrate 160 while simultaneously grinding the plurality of substrates 160.

  As shown in FIG. 3, the substrate 160 has a substantially square main surface (surface to be ground), and the carrier 150 includes nine substrate receiving holes 151 for receiving the substrate 160. The shape of the substrate receiving hole 151 may be substantially the same as the shape of the surface to be ground of the substrate 160. However, in this embodiment, considering the work efficiency when the operator places the substrate 160 in the substrate accommodation hole 151 or removes the substrate 160 from the substrate accommodation hole 151, the substrate 160 is removed with the operator's fingers or a removal jig. Substantially circular cutouts are provided at the four corners of the substrate receiving hole 151 so that the corners of the substrate 160 are not easily chipped when the corners of the substrate 160 strongly contact the carrier for some reason. In addition, rectangular cutouts are provided at the center of the four sides of the substrate accommodation hole 151.

  The shorter the distance between the substrate accommodation holes 151 in the carrier 150, the more substrate accommodation holes 151 can be provided in the carrier 150. However, if the distance is too short, the diamond sheets 155 and 165 come into contact with the substrate 160 accommodated in the adjacent substrate accommodation hole 151 while the upper surface plate 140 and the lower surface plate 170 are orbital. Become. When the diamond sheets 155 and 165 come into contact with the substrate 160 accommodated in the adjacent substrate accommodation hole 151, the diamond sheet 155 and 165 are first brought into contact with the ends of the ground surfaces of the diamond sheets 155 and 165. , 165 may partially peel from the upper surfaces of the sliding surface plate 147 and the lower surface plate 170. Therefore, the distance between the substrate receiving holes 151 is set so as to grind only the substrate 160 that the diamond sheets 155 and 165 are supposed to be in charge of.

The carrier 150 is formed using a material having a lower hardness than the substrate 160 so that the substrate 160 is not damaged by contact with the substrate 160. Examples of such a low-hardness material include polycarbonate resin, acrylic resin, silicon resin, and fluorine resin. The carrier 150 is made thinner than the substrate 160 so as not to impede contact between the substrate 160 and the diamond sheets 155 and 165. The carrier 150 is fixed by sandwiching both end portions 152 between the slide device 180 and the fixing plate 185. The carrier 150 is tensioned from both sides by the slide device 180 and the fixed plate 185 so as not to contact the diamond sheet 165.

  While the upper surface plate 140 and the lower surface plate 170 are orbitally moved and the substrate 160 is being ground, the carrier 150 reciprocates at a cycle slower than the cycle of the orbital motion. Since the carrier 150 performs such a reciprocating motion, the contact portion between the ground surface of the substrate 160 and the ground surfaces of the diamond sheets 155 and 165 gradually shifts, so that the ground surface of the ground substrate 160 is ground. Surface characteristics such as waviness of the diamond sheets 155 and 165 are hardly transferred. Therefore, when the carrier 150 performs such a reciprocating operation, the surface flatness of the substrate 160 after grinding can be further increased.

  FIG. 4 shows the positional relationship between the substrate 160 and the diamond sheet 165 attached to the upper surface of the lower surface plate 170 when all the substrates 160 are accommodated in the nine substrate accommodation holes 151 of the carrier 150 shown in FIG. In FIG. 4, the carrier 150 is omitted, and the diamond sheet 165 is indicated by a dotted line. As shown in FIG. 4, when the substrate 160 is disposed in the substrate accommodation hole 151, the positional relationship between the substrate accommodation hole 151 and the diamond sheet 165 is set so that a part of the diamond sheet 165 does not contact the substrate 160. ing. Although not shown, the positional relationship between the substrate 160 and the diamond sheet 155 is a mirror image relationship with the positional relationship between the substrate 160 and the diamond sheet 165.

  Then, the upper surface plate 140 and the lower surface plate 170 are orbital moved while the diamond sheets 155 and 165 are in contact with the substrate 160, whereby both surfaces to be ground of the substrate 160 are ground simultaneously. FIG. 5 shows the relative positional relationship between the substrate 160 and the diamond sheet 165 at the time of grinding. In FIG. 5, (a) corresponds to the state shown in FIG. 4, and (b) to (e) show a state in which the rotation angle of the orbital motion of the lower surface plate 170 is sequentially advanced by 45 ° from the state of (a). . 5A, a part of the diamond sheet 165 is not in contact with the substrate 160. However, as the orbital motion of the lower surface plate 170 proceeds, the entire grinding surface of the diamond sheet 165 is in contact with the substrate 160. Yes. Thus, while the upper surface plate 140 and the lower surface plate 170 are orbital, the entire contact surface of the diamond sheet 155 with the substrate 160 and the entire contact surface of the diamond sheet 165 with the substrate 160 are By contacting the substrate 160, the entire grinding surfaces of the diamond sheets 155 and 165 are evenly worn. As a result, even if the number of processed substrates 160 to be ground by the grinding apparatus 100 increases, it is possible to suppress the deterioration of the surface flatness of the ground surface of the substrate 160 after grinding. Therefore, according to the grinding apparatus 100, since the work for correcting the surface flatness of the diamond sheet 155 and the diamond sheet 165 can be reduced, the productivity can be increased.

  While the upper surface plate 140 and the lower surface plate 170 are orbital, the entire contact surface of the diamond sheet 155 with the substrate 160 and the entire contact surface of the diamond sheet 165 with the substrate 160 are in contact with each other. To achieve this, when the diamond sheets 155 and 165 of the substrate 160 are square, it is certain that the following conditions are satisfied. When the length of one side of the diamond sheets 155 and 165 is La, the length of one side of the substrate 160 is Lq, and the radius of rotation of the orbital motion of the upper surface plate 140 and the lower surface plate 170 is R,

の関係が成り立つように、Ｌｑ、Ｌａ、Ｒをそれぞれ設定することが好ましい。

It is preferable to set Lq, La, and R so that the following relationship holds.

  4 and 5, the shape of the ground surface of the substrate 160 in the diamond sheets 155 and 165 is substantially the same as the ground surface of the substrate 160, and the size thereof is larger than the area of the ground surface of the substrate 160. The small case is shown.

  In this embodiment, the orbital motion of the upper surface plate 140 and the orbital motion of the lower surface plate 170 have the same rotation radius, rotational speed, and direction of rotation, and therefore the behavior of the upper surface plate 140 during the orbital motion is the lower surface plate 170. It is in a mirror image relationship with the behavior. Therefore, if the relative positional relationship between the substrate 160 and the diamond sheet 155 is illustrated, the left and right in FIGS. 5A to 5E are reversed. Thus, in this embodiment, since the upper surface plate 140 and the lower surface plate 170 continue to maintain a mirror image relationship during orbital motion, the contact portion of the substrate 160 with the diamond sheet 155 and the contact portion of the diamond sheet 165 are: It is facing in the vertical direction. Therefore, in the present embodiment, while the upper surface plate 140 and the lower surface plate 170 are orbital, a predetermined range of the substrate 160 is pressed evenly from above and below by the diamond sheets 155 and 165. The substrate 160 can be prevented from vibrating vertically between the diamond sheets 155 and 165. As a result, if the grinding apparatus 100 is used, it is possible to prevent occurrence of uneven grinding during grinding of the substrate 160.

  The orbital motion of the upper surface plate 140 and the lower surface plate 170 preferably has a rotation speed of 20 to 100 rpm. If this rotational speed is slower than 20 rpm, it takes too much time to grind the substrate 160, which is not suitable for industrial production. On the other hand, when the rotational speed exceeds 100 rpm, the behavior of the upper surface plate 140 and the lower surface plate 170 becomes unstable.

  The amplitude distance of the reciprocating motion of the carrier 150 by the slide device 180 is smaller than the rotational diameter of the orbital motion of the upper surface plate 140 and the lower surface plate 170, and the speed of the reciprocating motion is the upper surface plate 140 and the upper surface plate 140 during the orbital motion. It is preferably slower than the linear velocity of the lower surface plate 170. Thus, since the reciprocating motion of the carrier 150 is slower than the orbital motion of the upper surface plate 140 and the lower surface plate 170, the behavior of the substrate 160 during grinding can be stabilized, and the surface flatness of the substrate 160 after grinding can be stabilized. The degree can be increased.

  The grinding apparatus 100 can adjust the pressure at which the grinding surfaces of the diamond sheets 155 and 165 contact the surface to be ground of the substrate 160 by changing the pressure of the compressed air supplied to the air cylinder 144. This contact pressure is preferably 0.1 to 1 MPa. If the contact pressure is less than 0.1 MPa, it takes too much time to grind the substrate 160, which is not suitable for industrial production. On the other hand, when the contact pressure exceeds 1 MPa, the diamond sheets 155 and 160 have too strong a force to sandwich the substrate 160, so that the substrate 160 is dragged by the diamond sheets 155 and 165, and the carrier receives the force from the substrate 160. 150 is easily damaged.

The diamond sheets 155 and 165 are obtained by electrodepositing diamond abrasive grains on a sheet-like base material, or fixing them with resin bonds or metal bonds. In general, as the diamond abrasive grains contained in the diamond sheets 155 and 165 increase, the amount of grinding of the substrate per unit time increases, but the surface flatness of the ground surface of the substrate after grinding deteriorates. Therefore, in selecting the diamond sheets 155 and 165, it is necessary to comprehensively consider the grinding conditions and the surface flatness of the substrate after grinding. For example, when this substrate is ground for 3 mm in 30 minutes while pressing the diamond sheets 155 and 165 at 0.4 MPa on both surfaces to be ground of the substrate made of quartz glass, a diamond abrasive having an average particle diameter of 10 to 100 μm. It is preferable to use diamond sheets 155 and 165 containing grains.

  While the substrate 160 is being ground by the diamond sheets 155 and 165, the central portions of the diamond sheets 155 and 165 are passed through a grinding liquid supply pipe (not shown) installed in the upper surface plate 140 and the lower surface plate 170. Thus, the grinding liquid is continuously supplied onto the surface of the substrate 160 to be ground. As the grinding liquid, pure water or water-soluble grinding oil typified by ethanolamine may be used. In order to increase the grinding amount of the substrate 160 per unit time, silicon carbide, silica, cerium oxide, or alumina is used. It is preferable to use a slurry containing fine particles such as. In addition, when using these slurries, in order not to hinder the grinding of the substrate 160 by the diamond sheets 155 and 165, a slurry containing fine particles having a particle diameter smaller than the diamond abrasive grains included in the diamond sheets 155 and 165 is used. It is preferable to use it.

  Further, while the upper surface plate 140 and the lower surface plate 170 are orbital, the maximum value of the non-contact area that is instantaneously separated from the substrate 160 in the diamond sheet 155 is the substrate 160 to be ground by the diamond sheet 155. And the maximum non-contact area of the diamond sheet 165 that is instantaneously separated from the substrate 160 is that of the surface to be ground of the substrate 160 to be ground by the diamond sheet 165. It is preferably 10% or more of the area. Furthermore, the maximum value of these non-contact areas is preferably 10 to 40% of the ground surface of the substrate 160. In the present embodiment, this non-contact area is maximized in the states of FIGS. 5 (a), (c), and (e). If the maximum value of the non-contact area is 10% or more of the surface of the substrate 160 to be ground, the diamond sheets 155 and 165 can be reliably brought into contact with the entire surface of the substrate 160 to be ground. On the other hand, if the maximum value of the non-contact area exceeds 40% of the area of the ground surface of the substrate 160, the area of the ground surface of the diamond sheets 155 and 165 is smaller than the area of the ground surface of the substrate 160. Since the sheets 155 and 165 do not come into contact with the central portion of the surface to be ground of the substrate 160, uneven grinding tends to occur on the surface to be ground of the substrate 160. If the maximum value of the non-contact area exceeds 40% of the area of the surface to be ground of the substrate 160, all the loads applied to the non-contact surface of the diamond sheets 155 and 165 with the substrate 160 are all ground on the substrate 160. Since it is applied to the outer peripheral portion of the surface, only the amount of grinding of the outer peripheral portion increases, resulting in a problem that the surface flatness of the substrate 160 after grinding deteriorates.

Since the grinding apparatus 100 grinds the substrate 160 using fixed abrasive grains, the grinding surfaces of the diamond sheets 155 and 166 wear out as the number of substrates 160 processed increases. Therefore, in the grinding apparatus 100, after processing a predetermined number of substrates 160, the diamond sheet 155 and the diamond sheet 165 are directly rubbed together to recover their surface flatness. At this time, the orbital motion of the upper surface plate 140 and the orbital motion of the lower surface plate 170 need to be different from each other in at least one of the rotational radius, rotational speed, and rotational direction. Therefore, according to the present embodiment, the surface flatness of the diamond sheets 155 and 165 can be recovered in a shorter time than the technique described in Patent Document 1. In the present embodiment, since the upper surface plate 140 and the lower surface plate 170 perform orbital motion, the surface flatness of the diamond sheets 155 and 165 is less likely to deteriorate compared to the technique described in Patent Document 1, and the diamond Since the sheets 155 and 165 are fixed to the upper surfaces of the sliding contact surface plate 147 and the lower surface plate 170 with an adhesive, the diamond sheets 155 and 165 can be replaced in a short time.

  The substrate 160 ground to a predetermined thickness by the grinding apparatus 100 is then polished using a polishing pad and loose abrasive grains such as colloidal silica until the surface to be ground has a desired surface flatness. Then, after the polished substrate 160 is immersed and washed in an acidic solution, a mask blank is manufactured by forming a thin film for forming a transfer pattern on the polished surface by a vapor phase method such as sputtering. . The mask blank of the present invention includes a binary mask blank, a phase shift mask blank, a reflective mask blank, an imprint mold production substrate, and a mask blank for imprint mold production.

  Examples of the thin film for forming a transfer pattern according to the present invention include a thin film made of metal, metal nitride, metal oxide, silicon nitride, silicon oxynitride, silicon carbide, silicide, nitride nitride, silicide oxide, or silicide carbide. Can be mentioned. Furthermore, examples of the metal include chromium, tantalum, molybdenum, titanium, hafnium, and tungsten. Examples of the silicide include a compound of silicon and chromium, tantalum, molybdenum, titanium, hafnium, or tungsten.

  A resist film is formed on the thin film for forming a transfer pattern of the mask blank by a known means, and the resist film is exposed to an electron beam or ultraviolet light and developed to form a transfer pattern on the thin film. The transfer mask according to the present invention includes, for example, a binary mask, a phase shift mask, a reflective mask, an imprint mold, and a reticle.

<Example>
A plate-like glass is cut out from a synthetic quartz ingot manufactured by a known method, chamfered, and the main surface is ground using a conventional grinding device to produce a composite of about 152.1 mm × 152.1 mm × 6.87 mm. 50 glass substrates made of quartz were obtained. Next, using the grinding apparatus 100 shown in the above embodiment, final grinding was performed on both main surfaces of the front and back surfaces of the mask blank glass substrate. Specifically, it was performed under the following conditions.

[Grinding conditions]
Upper surface plate rotation speed: 50 rpm, lower surface plate rotation speed: 50 rpm
Grinding time: 10 minutes, grinding pressure: 0.1 MPa
Number of substrates placed on carrier: 5 Fixed abrasive part: Diamond sheet (2.5 mm square, effective height 800 μm
A structure in which a fixed abrasive unit is affixed to a sheet at intervals of 1.5 mm),
Size per sheet 140mm x 140mm
10 sheets (5 sheets at a time)
Substrate grinding amount: 35μm

  50 glass substrates were ground with the same fixed abrasive part (diamond sheet). That is, 10 batches (sets) of the grinding process were performed. For each ground glass substrate, the flatness of the main surface was measured by a wavelength shift interferometer using a wavelength varying laser. The result is shown in FIG. In FIG. 6, the average value of the flatness of the main surface in five substrates ground in the same batch is compared between the first batch, the third batch, the sixth batch, the eighth batch, and the tenth batch. As the batch progressed, there was no tendency for the average value of the flatness to deteriorate, and it was confirmed that the deterioration of the flatness on the ground surface (fixed surface ground surface) of the fixed abrasive part could be suppressed.

  Further, even the glass substrate with the lowest flatness is 0.921 μm, and even if 10 sets are ground using the same fixed abrasive part, it is sufficiently possible to produce a glass substrate with a flatness of 1.0 μm or less. It was confirmed that.

<Comparative example>
The same diamond sheet as that used in the above embodiment is pasted on the entire grinding surface of the upper surface plate and the lower surface plate of the grinding apparatus for grinding by moving the planetary gear of the conventional substrate as shown in FIG. A grinding machine was prepared. Using this grinding apparatus, final grinding of both the front and back main surfaces was performed on 50 glass substrates having the same material and dimensions as those subjected to final grinding in the examples. Specifically, it was performed under the following conditions.

[Grinding conditions]
Upper surface plate rotation speed: 50 rpm, lower surface plate rotation speed: 50 rpm
Grinding time: 10 minutes, grinding pressure: 0.4 MPa
Number of substrates placed on the carrier: 5 Fixed abrasive grains: Diamond sheet with the same structure as the example (size: same size as the surface plate)
Substrate grinding amount: 35μm

  50 glass substrates were ground with the same fixed abrasive part (diamond sheet). That is, 10 batches (sets) of the grinding process were performed. For each ground glass substrate, the flatness of the main surface was measured by a wavelength shift interferometer using a wavelength varying laser. The results are shown in FIG. In FIG. 7, the average value of the flatness of the main surface of five substrates ground in the same batch is compared between the first batch, the third batch, the sixth batch, the eighth batch, and the tenth batch as in the example. It is a thing. As the batch progressed, the tendency for the average value of flatness to deteriorate was noticeable. In addition, the average value of the flatness of the main surface of the substrate has deteriorated to a little less than 2 μm as early as the sixth batch, and the flatness cannot be improved by the polishing process of the main surface, which is a subsequent process. From these results, it is clear that the above-mentioned problem cannot be solved only by affixing fixed abrasive grains such as a diamond sheet on the surface grinding surface of a conventional grinding apparatus.

<Other Embodiments of the Present Invention>
Other embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

  FIG. 8 is a plan view of the carrier 600 according to the present embodiment. The carrier 600 is used in place of the carrier 150 in the grinding apparatus 100. The carrier 600 has five circular adapter accommodation holes 610 at the center thereof, five adapters 620 accommodated in the adapter accommodation holes 610, substrate accommodation holes 630 formed in the center of the adapter 620, and both ends. Part 652 is provided. Similar to the carrier 150, the carrier 600 is fixed to the slide device 180 by the end portion 652 being sandwiched between the slide device 180 and the fixing plate 185. The adapter 620 is rotatably accommodated in the adapter accommodation hole 610 and has a substantially square substrate accommodation hole 630 that is the same as the surface to be ground of the substrate 160 for accommodating the substrate 160 in the center thereof.

  In this embodiment, since the carrier 600 is used instead of the carrier 150, the diamond sheets 155 and 165 are attached to the upper surfaces of the sliding surface plate 147 and the lower surface plate 170 so as to correspond to the positions of the substrate accommodation holes 630. Specifically, the diamond sheets 155 and 165 are arranged so that the sliding contact surface plate 147 and the lower surface of the diamond sheets 155 and 165 are positioned so as to be in a positional relationship with the substrate 160 shown in FIG. 5A when the substrate 160 is disposed in the substrate accommodation hole 630. It is attached to the upper surface of the board 170.

  While the upper surface plate 140 and the lower surface plate 170 perform orbital motion, the substrate 160 receives power from the diamond sheets 155 and 165 and rotates in the substrate accommodation hole 630 together with the adapter 620. When the substrate 160 rotates in the substrate accommodation hole 630, the contact portion between the surface to be ground of the substrate 160 and the ground surface of the diamond sheets 155 and 165 easily changes, and the grinding surface of the diamond sheets 155 and 165 swells. Therefore, the surface flatness of the substrate 160 after grinding becomes higher.

  Here, the diameter (inner diameter) of the adapter accommodation hole 610 is preferably 1 to 10 mm larger than the diameter (outer diameter) of the adapter 620. When the difference between these diameters is less than 1 mm, slurry used during grinding of the substrate 160 and grinding waste generated during grinding accumulates between the adapter accommodation hole 610 and the adapter 620, and within the adapter accommodation hole 610. It becomes difficult for the adapter 620 to rotate. On the other hand, if the difference between these diameters exceeds 10 mm, the play between the adapter accommodation hole 610 and the adapter 620 becomes too large, and the substrate 160 is dragged by the diamond sheets 155 and 165 during grinding to move inside the adapter accommodation hole 610. Since it moves around, the grinding amount of the substrate 160 per unit time decreases.

<Still another embodiment of the present invention>
In each embodiment of the present invention, the case where the diamond sheets 155 and 165 are used as the fixed abrasive portion has been described. However, the present invention is not limited to this case, and silicon carbide fine particles and alumina fine particles are used as the abrasive particles. You may use the fixed abrasive part to contain.

  Further, in each of the embodiments of the present invention, the case has been described in which nine substrate housing holes 151 are provided in the carrier 150 and five adapter housing holes 610 are provided in the carrier 600, but the present invention is limited to this case. Instead, the number can be increased or decreased as appropriate.

  Moreover, although each embodiment of this invention demonstrated the case where the rotational radius, rotational speed, and rotational direction in the orbital motion of the upper surface plate 140 and the lower surface plate 170 were the same, this invention is limited to this case. The rotational radius, rotational speed, and rotational direction in the orbital motion of the upper surface plate 140 and the rotational radius, rotational speed, and rotational direction in the orbital motion of the lower surface plate 170 may be set separately. . Here, in another embodiment of the present invention, when the orbital motion of the upper surface plate 140 and the orbital motion of the lower surface plate 170 are the same, the substrate 160 is dragged by the diamond sheets 155 and 165. As a result, the surface to be ground of the substrate 160 and the ground surfaces of the diamond sheets 155 and 165 are hardly rubbed together, so that the amount of grinding of the substrate 160 per unit time is reduced. Therefore, in another embodiment of the present invention, in order to prevent the substrate 160 from being dragged by the diamond sheets 155 and 165, the rotational radius, rotational speed, and rotational direction in the orbital motion of the upper surface plate 140 are reduced. It is preferable to set so as not to coincide with the rotation radius, rotation speed, and rotation direction in the orbital motion of the board 170. In particular, in another embodiment of the present invention, it is preferable that the rotational direction of the orbital motion of the upper surface plate 140 is set to be opposite to the rotational direction of the orbital motion of the lower surface plate 170.

  The present invention can make the ground surface of the substrate extremely flat and flat, and therefore can be used not only for grinding a mask blank substrate but also for grinding a magnetic disk substrate.

DESCRIPTION OF SYMBOLS 100 Grinding apparatus 110 Frame 120 Motor 121 Shaft 130 Eccentric coupling part 131 Eccentric shaft 140 Upper surface plate 141 Bearing unit 142 Air gap 143 Air pipe 144 Air cylinder 145 Press plate 146 Surface adjustment unit 147 Sliding surface plate 149 Housing 150, 600 Carrier 151, 630 Substrate accommodation holes 152, 652 Ends 155, 165 Diamond sheet 170 Lower surface plate 180 Slide device 185 Fixed plate 610 Adapter accommodation hole 620 Adapter

Claims (13)

A substrate is brought into contact with an upper surface plate having a fixed abrasive portion to which abrasive grains are fixed, a lower surface plate having a fixed abrasive portion to which abrasive grains are fixed, and both fixed abrasive portions of the upper surface plate and the lower surface plate. A carrier for holding the mask blank, and a mask blank substrate manufacturing apparatus comprising:
While the upper surface plate and the lower surface plate are orbitally moved, the entire contact surface with the substrate in the fixed abrasive portion of the upper surface plate, and the substrate in the fixed abrasive portion of the lower surface plate A method for manufacturing a mask blank substrate, wherein the entire contact surface is brought into contact with each surface to be ground of the substrate.   The method for producing a mask blank substrate according to claim 1, wherein the fixed abrasive portion is a portion to which diamond abrasive grains are fixed.   3. The method of manufacturing a mask blank substrate according to claim 1, wherein the orbital motion of the upper surface plate and the orbital motion of the lower surface plate have the same rotational radius, rotational speed, and rotational direction.   4. The method of manufacturing a mask blank substrate according to claim 1, wherein the carrier reciprocates while the upper surface plate and the lower surface plate are orbital. While the upper surface plate and the lower surface plate are orbital motion,
The maximum value of the non-contact area that is instantaneously separated from the substrate in the fixed abrasive part of the upper surface plate is 10 of the area of the surface to be ground of the substrate that is ground by the fixed abrasive part of the upper surface plate. % Or more,
The maximum value of the non-contact area that is instantaneously separated from the substrate in the fixed abrasive part of the lower surface plate is 10% or more of the area of the surface to be ground of the substrate that is ground by the fixed abrasive part of the lower surface plate. The method for producing a mask blank substrate according to claim 1, wherein:   When correcting the flatness of the fixed abrasive part, the contact surface of the fixed abrasive part of the upper surface plate with the substrate and the contact surface of the fixed abrasive part of the lower surface plate with the substrate are in direct contact. The method for manufacturing a mask blank substrate according to claim 1, wherein the mask blank substrate is rubbed together. An upper surface plate that has a fixed abrasive part to which abrasive grains are fixed and performs orbital motion;
A lower surface plate having a fixed abrasive grain portion to which abrasive grains are fixed and performing orbital motion;
A carrier for holding the substrate in contact with both fixed abrasive parts of the upper surface plate and the lower surface plate, and
While the upper surface plate and the lower surface plate are orbital,
The entire contact surface with the substrate in the fixed abrasive portion of the upper surface plate and the entire contact surface with the substrate in the fixed abrasive portion of the lower surface plate are in contact with the substrate, respectively. A device for manufacturing a mask blank substrate.   The fixed abrasive part of the said upper surface plate, the fixed abrasive part of the said lower surface plate, and the through-hole holding the said board | substrate in the said carrier are the same number, The mask blank for Claim 7 characterized by the above-mentioned. Board manufacturing equipment.   9. The apparatus for manufacturing a mask blank substrate according to claim 7 or 8, wherein the both fixed abrasive portions of the upper and lower surface plates have diamond abrasive grains fixed thereto.   10. The mask blank substrate according to claim 7, wherein the orbital motion of the upper surface plate and the orbital motion of the lower surface plate have the same rotational radius, rotational speed, and rotational direction. manufacturing device.   11. The mask blank substrate manufacturing apparatus according to claim 7, wherein the carrier reciprocates while the upper surface plate and the lower surface plate are orbital.   7. A precision polishing is performed on a main surface of a mask blank substrate manufactured by the method for manufacturing a mask blank substrate according to claim 1, and a thin film for forming a transfer pattern is further formed on the main surface. A method for manufacturing a mask blank, characterized in that:   A method for producing a transfer mask, comprising: patterning the thin film in a mask blank produced by the method for producing a mask blank according to claim 12 to form a transfer pattern.

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