JP6564727B2 - Mask manufacturing apparatus and mask manufacturing apparatus control method - Google Patents

Description

  The present invention relates to a mask manufacturing apparatus and a mask manufacturing apparatus control method.

  Patent Document 1 discloses a substrate holding device that holds a substrate via a movable contact portion that is moved or deformed by a common fluid.

JP 2012-79917 A

  When producing a semiconductor substrate, a liquid crystal panel or the like, it is generally necessary to process the substrate within an error range of 10 nm or less (preferably 2 nm or less) in order to produce a product free from defects such as display unevenness. . Such high-precision processing is generally performed using laser light that has been scanned and modulated (or may be deflected and modulated).

  However, if a substrate such as a semiconductor substrate or a liquid crystal panel is to be processed with high precision using a scanned / modulated laser beam, it takes a long time (several days) to process one substrate. End up. Therefore, a highly accurate mask for generating a semiconductor substrate, a liquid crystal panel, or the like is generated using laser light, and the pattern of the mask is transferred to a substrate such as a semiconductor substrate or a liquid crystal panel.

  In such a mask generation apparatus, a photosensitive substrate (for example, a glass substrate) is held horizontally on a stage, and the scanned and modulated laser light is irradiated while moving the photosensitive substrate in the horizontal direction. Generate a mask.

  The invention described in Patent Document 1 discloses that a photosensitive substrate (hereinafter referred to as a mask) is held in a horizontal direction so that there is no deflection due to its own weight. However, the pattern position accuracy cannot be increased only by holding the mask so that there is no deflection due to its own weight.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a mask manufacturing apparatus and a mask manufacturing apparatus control method capable of increasing the positional accuracy of a pattern.

  In order to solve the above problems, a mask manufacturing apparatus according to the present invention is, for example, a plate-like stage on which a mask is placed on a substantially horizontal upper surface, and bar mirrors along two adjacent sides of the upper surface. A provided stage, a substantially rectangular parallelepiped surface plate, a first moving unit placed on the surface plate, a plate-like portion, and a first drive unit that moves the plate-like portion in a first direction; And a second moving part placed on the upper surface of the plate-like part and having the stage placed thereon, the second moving part moving the stage in the second direction. A second moving unit having a driving unit, a light irradiating unit for irradiating the mask with light, a light irradiating unit provided with two mirrors parallel to the bar mirror, and provided on the surface plate, A frame holding the light irradiation unit above the stage, and the second direction of the first moving unit; The first position measuring unit and the second position measuring unit for obtaining the position of the plate-like part in the first direction, and provided on both sides of the second moving unit in the first direction, A position measuring unit having a third position measuring unit and a fourth position measuring unit for acquiring a position of the stage in the second direction; and measuring the position of the bar mirror with reference to the positions of the two mirrors. The laser interferometer that measures the positional relationship between the light irradiation unit and the stage, and the drawing information that is information on the position and shape of the pattern drawn on the mask are acquired, and the value acquired by the position measuring unit is obtained. Based on the drawing information, the mask is irradiated with light while driving the first driving unit and the second driving unit to move the stage in the horizontal direction based on the drawing information. A control unit that performs image processing, and the control unit converts the value acquired by the first position measurement unit and the value acquired by the second position measurement unit into the first position measurement unit and the second position. The weighted average value weighted according to the distance between the measurement unit and the light irradiation unit, the value acquired by the third position measurement unit, and the value acquired by the fourth position measurement unit are the third position measurement unit. And based on the weighted average value weighted according to the distance between the fourth position measurement unit and the light irradiation unit, obtain a measurement value when assuming that the position measurement unit is at the position of the light irradiation unit, The position measurement unit is calibrated by comparing the obtained measurement value with the measurement result of the laser interferometer, and the drawing process is performed based on the value acquired by the calibrated position measurement unit. And

  According to the mask manufacturing apparatus of the present invention, the values acquired by the first position measuring unit and the second position measuring unit provided on both sides in the second direction of the first moving unit that moves the stage in the first direction are obtained. The weighted average value weighted according to the distance between the first position measuring unit and the second position measuring unit and the light irradiation unit, and both sides in the first direction of the second moving unit that moves the stage in the second direction A weighted average value obtained by weighting the values acquired by the third position measuring unit and the fourth position measuring unit provided in the first position measuring unit according to the distance between the third position measuring unit and the fourth position measuring unit and the light irradiation unit. Based on the above, a measurement value is obtained when it is assumed that there is a measurement unit at the position of the light irradiation unit that irradiates the mask with light. Further, the positional relationship between the light irradiation unit and the stage is measured with a laser interferometer by measuring the position of the bar mirror provided on the stage with reference to the positions of the two mirrors provided in the light irradiation unit. Then, the position measurement unit is calibrated by comparing the obtained measurement value with the measurement result of the laser interferometer, and drawing on the mask is performed using the measurement by the position measurement unit after calibration. As described above, the stage (mask) can be accurately moved in the horizontal direction by calibrating the position measurement unit using the laser interferometer. Therefore, the position accuracy of the pattern drawn on the mask M can be increased.

  Here, the reading unit provided adjacent to the light irradiation unit or provided in the light irradiation unit, the control unit is information regarding a correction substrate pattern including a plurality of cross positions arranged two-dimensionally Is acquired based on the correction substrate drawing information while controlling the first driving unit and the second driving unit to move the stage in the first direction and the second direction. Irradiating the mask with light from the light irradiation unit, drawing the correction substrate pattern on the mask to generate a correction substrate, and an initial state when the correction substrate is generated; The correction substrate is read by the reading unit in each of a state in which the correction substrate is rotated approximately 90 degrees, approximately 180 degrees, and approximately 270 degrees from the initial state, and the correction substrate is read based on the read result. drawing Correcting the distribution may perform the rendering process on the basis of the corrected drawing information. Thereby, it is possible to calibrate itself by the light irradiation unit alone, thereby increasing the position accuracy of the pattern. In addition, since the correction substrate pattern including a plurality of cross positions is used, the drawing information can be corrected in each of the first direction and the second direction.

  Here, the control unit matches the result of reading the correction substrate in the initial state with the result of reading the correction substrate in a state where the correction substrate is rotated by approximately 180 degrees. A correction value such that the result of reading the correction substrate with the substrate for rotation approximately 90 degrees coincides with the result of reading the substrate for correction with the substrate for correction rotated approximately 270 degrees And the drawing information may be corrected using the generated correction value. Thereby, the pattern drawn on the substrate and the pattern shown in the drawing information can be completely matched.

  Here, the light irradiation unit includes an autofocus unit that focuses the light irradiated onto the mask on the mask, and the control unit controls the autofocus unit to control the light irradiation unit and the light irradiation unit. Distance information regarding the distance to the mask may be acquired, the drawing information may be corrected based on the acquired distance information, and the drawing process may be performed based on the corrected drawing information. As a result, even if a change in the height direction of the mask M occurs (for example, due to the deflection of the mask M due to dust adhering between the mask and the stage or the thickness distribution of the mask), the pattern is accurately Can be drawn.

  Here, the light irradiation unit includes a surface irradiation unit in which pixels are two-dimensionally arranged, and the drawing information includes the position of the surface irradiation unit and the light irradiation in each pixel of the surface irradiation unit. Position information associated with presence / absence, irradiation timing information associated with the position of the surface irradiation unit and the light irradiation timing of each pixel of the surface irradiation unit, and the control unit includes the first For the direction, the irradiation timing information is shifted, and for the second direction, the drawing information is corrected by shifting the position information, and the stage is moved in the first direction to perform drawing for one row. The drawing process may be performed by moving the stage in the second direction. Thereby, in the case of surface irradiation with laser light, it is possible to correct the drawing information and irradiate light.

  Here, the light irradiation unit may include an optical member, and the control unit may correct the drawing information by moving the optical member. Thereby, in the case of surface irradiation with laser light, it is possible to correct the drawing information and irradiate light.

Here, the stage is formed using a material having a thermal expansion coefficient of approximately 1 × 10 ⁻⁷ / K or less, and the control unit includes the second driving unit so that the stage does not protrude from the plate-like part. May be controlled. As a result, the deflection of the mask M can be prevented, and the pattern position accuracy can be increased.

  In order to solve the above problems, for example, a mask manufacturing apparatus according to the present invention is mounted on a substantially rectangular parallelepiped surface plate, and has a plate-like portion and a first drive portion that moves the plate-like portion in a first direction. The values acquired by the first position measuring unit and the second position measuring unit provided on both sides in the second direction of the first moving unit having the first position measuring unit, the second position measuring unit, A weighted average value weighted according to the distance to the light irradiation unit and a plate-like stage placed on the upper surface of the plate-like portion and on which the mask is placed are placed on the second stage. The values acquired by the third position measuring unit and the fourth position measuring unit provided on both sides in the first direction of the second moving unit having the second driving unit to be moved to the third position measuring unit and the second position measuring unit Weight weighted according to the distance between the 4-position measurement unit and the light irradiation unit A step of obtaining a measurement value when it is assumed that there is a measurement unit at the position of the light irradiation unit that irradiates the mask with light based on the average value, the obtained measurement value, and the light irradiation unit The measurement result of a laser interferometer that measures the positional relationship between the light irradiation unit and the stage by measuring the position of the bar mirror provided on the stage with reference to the position of the two mirrors provided on the stage, and Calibrating the first position measurement unit, the second position measurement unit, the third position measurement unit, and the fourth position measurement unit based on the first position measurement unit, and the first position measurement unit calibrated by the calibration step The stage is moved horizontally by driving the first driving unit and the second driving unit based on values acquired by the second position measuring unit, the third position measuring unit, and the fourth position measuring unit. While moving to And irradiating light to the mask from the light irradiating unit characterized in that it comprises a and a step of performing drawing on the mask based on the information in which the drawing information about the position and shape of the pattern to be drawn in. Thereby, the position measuring unit can be calibrated using the laser interferometer, and the position accuracy of the pattern drawn on the mask M can be increased.

  According to the present invention, the pattern position accuracy can be increased.

It is a perspective view showing the outline of mask manufacturing device 1 concerning a 1st embodiment. 3 is a perspective view showing an outline of a first moving unit 20 and a second moving unit 30. FIG. It is the figure which expanded the 1st moving part 20 partially. It is the perspective view which looked at the plate-shaped part 23 from the back side. It is the figure which expanded the 2nd moving part 30 partially. It is the schematic perspective view which looked at the stage 41 from diagonally upward. It is the schematic perspective view which looked at the stage 41 from diagonally downward. It is a principal part perspective view which shows the outline of the light irradiation part 43a. It is the perspective view which shows the outline of the pattern reading part 47a, and is the figure which saw through the principal part. It is the perspective view which shows the outline of the optical reading part 48a, and is the figure which saw through the principal part. It is a schematic diagram which shows a mode that the laser interferometers 51, 52, and 53 measure. 2 is a block diagram showing an electrical configuration of the mask manufacturing apparatus 1. FIG. This is an example in which the measurement results of the two position measurement units 29 and the measurement results of the laser interferometers 52 and 53 are compared when the plate-like portion 23 is moved in the x direction. It is a graph which shows the correction value of a x direction when the measurement result shown in FIG. 13 is obtained. It is a figure explaining a mode that the biasing parts 45 and 46 press the mask M, and position it. It is a figure which shows an example of the correction | amendment board | substrate drawing information. It is a figure which shows the correction | amendment board | substrate M1 produced | generated based on the correction | amendment board | substrate drawing information shown in FIG. FIG. 10 is a diagram illustrating a result of reading the correction substrate M1 using the pattern reading unit 47 in a state where the correction substrate M1 is rotated approximately 180 degrees from the initial state. 4 is a schematic diagram showing a state of the mask M when dust D is adhered between the mask M and the upper surface 41a of the stage 41. FIG. It is a figure explaining control of the drive parts 25 and 34 which the control part 151a performs. It is a figure explaining the drawing position correction process which the control part 151a performs. It is a schematic diagram which shows a mode that the position (image position) where the light irradiated from the light source 432 forms an image is moved to a horizontal direction. It is a schematic diagram which shows a mode that the position (image position) where the light irradiated from the light source 432 forms an image is moved to a horizontal direction.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same elements are denoted by the same reference numerals, and the description of overlapping parts is omitted.

The mask manufacturing apparatus in the present invention is an apparatus that generates a photomask by irradiating light such as laser onto a photosensitive substrate (for example, a glass substrate) held in a substantially horizontal direction. As the photosensitive substrate, for example, quartz glass having a very small coefficient of thermal expansion (for example, about 5.5 × 10 ⁻⁷ / K) is used.

  The photomask produced | generated by a mask manufacturing apparatus is an exposure mask used in order to manufacture the board | substrate for liquid crystal display devices, for example. The photomask is obtained by forming one or a plurality of image device transfer patterns on a large, substantially rectangular substrate having a side exceeding 1 m (for example, 1400 mm × 1220 mm). Hereinafter, the term “mask M” is used as a concept encompassing a photosensitive substrate before processing and a photosensitive substrate (photomask) after processing.

  FIG. 1 is a perspective view schematically showing a mask manufacturing apparatus 1 according to the first embodiment. The mask manufacturing apparatus 1 mainly includes a surface plate 11, vibration isolation tables 12 and 13, a first moving unit 20, a second moving unit 30, a stage 41, a frame body 42, a light irradiation unit 43, A pattern reading unit 47. In FIG. 1, illustration of a part of the configuration is omitted. The mask manufacturing apparatus 1 is maintained at a constant temperature by a temperature adjusting unit (not shown) that covers the entire apparatus.

  The surface plate 11 is a member having a substantially rectangular parallelepiped shape (thick plate shape), and is formed of, for example, a stone (for example, granite) or a low expansion coefficient casting (for example, a nickel-based alloy). The surface plate 11 is placed on a plurality of vibration isolation tables 12 and 13 placed on an installation surface (for example, a floor). As a result, the surface plate 11 is placed on the installation surface via the vibration isolation tables 12 and 13. The surface plate 11 has a substantially horizontal (substantially parallel to the xy plane) upper surface (+ z side surface) 11a.

  The vibration isolation table 12 is an active vibration isolation table, and the vibration isolation table 13 is a weight-supported passive vibration isolation table. The vibration isolation table 13 has a passive spring element that is movable in the z direction. The vibration isolation table 12 is connected to the vibration isolation table 13 with an actuator (not shown) that can move in each of the x and y directions, a sensor (not shown) for controlling the actuator, and a signal from the sensor. And a control circuit (not shown) for controlling the actuator so as to suppress vibration input from the outside. Since the vibration isolation tables 12 and 13 are already known, detailed description thereof is omitted.

  The first moving unit 20 is placed on the upper surface 11 a of the surface plate 11, the second moving unit 30 is placed on the first moving unit 20 (+ z side), and the stage 41 is placed on the second moving unit 30. Placed on the top. The first moving unit 20 moves the stage 41 in the x direction, and the second moving unit 30 moves the stage 41 in the y direction.

  FIG. 2 is a perspective view schematically showing the first moving unit 20 and the second moving unit 30. Although not shown in FIG. 2, air is supplied to the first moving unit 20 and the second moving unit 30 from a pump or the like.

  The first moving unit 20 mainly sandwiches the four rails 21, the one guide rail 22, the plate 21 placed on the rail 21 and the guide rail 22, and the guide rail 22. It has the convex part 24 provided, the drive part 25 which moves the plate-shaped part 23 along the upper surface of the rail 21, the rod-shaped member 26, the magnet 27, and the position measurement part 29.

  The four rails 21 and the guide rails 22 are elongated plate-like members made of ceramic, and are fixed to the upper surface 11a of the surface plate 11 so that the longitudinal direction is along the x direction. The four rails 21 and the guide rails 22 have substantially the same height (position in the z direction). The upper surfaces of the rails 21 and the guide rails 22 and the side surfaces of the guide rails 22 are formed with high accuracy and high flatness.

  The guide rail 22 is provided substantially at the center of the surface plate 11 in the y direction. The surface substantially parallel to the xz plane and including the guide rail 22 includes the position of the center of gravity of the mask manufacturing apparatus 1.

  The four rails 21 are provided at line-symmetric positions with the guide rail 22 interposed therebetween. In the present embodiment, the two rails 21 are provided on the −y side of the guide rail 22, and the two rails 21 are provided on the + y side of the guide rail 22. The rail 21 a located at the −y side end of the four rails 21 is placed in the vicinity of the end surface 23 e, which is the −y side end of the plate-like portion 23, and the four rails 21. The rail 21b located at the end on the + y side is mounted on the area near the end surface 23f, which is the end on the + y side of the plate-like portion 23.

  The plate-like portion 23 is a ceramic plate-like member, and has a substantially rectangular shape as a whole. The plate-like portion 23 has a substantially horizontal upper surface 23a and lower surface 23b (see FIG. 3). The second moving unit 30 is placed on the upper surface 23a. The bottom surface 23b is provided with a rod-like convex portion 24 so that the longitudinal direction is along the x direction.

  FIG. 3 is a partially enlarged view of the first moving unit 20. By providing the convex portion 24 on the lower surface 23 b, a groove 23 d is formed on the lower surface 23 b of the plate-like portion 23. The guide rail 22 is inserted into the groove 23d. Thereby, the movement direction of the plate-like part 23 is regulated so that the position of the plate-like part 23 in the y direction, that is, the plate-like part 23 does not move in any direction other than the x-direction.

  The convex portion 24 is provided with an air discharge portion 24 a that discharges air toward the side surface of the guide rail 22. The air discharge part 24 a has an air hole that opens on the side surface of the convex part 24. Moreover, the air discharge part 24a has an orifice with a narrowed inner diameter. Therefore, air supplied from a pump (not shown) or the like is discharged from this opening at high pressure and high speed. Thereby, an air layer is formed between the air discharge portion 24 a and the guide rail 22.

  On the lower surface 23 b of the plate-like portion 23, a convex portion 23 c is formed at a position facing the rail 21 and the guide rail 22. The protrusion 23c has a flat tip (a surface facing the rail 21 or the guide rail 22). An air discharge portion 28 is provided on the convex portion 23c. In FIG. 3, illustration of the convex portion 23 c formed at a position facing the guide rail 22 is omitted.

  FIG. 4 is a perspective view of the plate-like portion 23 as seen from the back side. The plurality of convex portions 23c are two-dimensionally arranged on the lower surface 23b. A plurality of (for example, five) air discharge portions 28 are provided on the convex portion 23c. The air discharge part 28 has an air hole opened in the front end surface of the convex part 23c. Moreover, the air discharge part 28 has an orifice with a narrowed inner diameter. Therefore, air supplied from a pump (not shown) or the like is discharged from the air discharge unit 28 toward the rail 21 and the guide rail 22 at high pressure and high speed. Thereby, an air layer is formed between the air discharge portion 28 and the rail 21 and the guide rail 22. Further, by providing the plurality of air discharge portions 28 on the convex portion 23c, the pressure of the air layer is increased.

  In the present embodiment, adjacent convex portions 23c are separated in both the x and y directions, but the form of the convex portions 23c is not limited to this. For example, the convex portion may be a long rib shape along the x direction, and a plurality of rib-shaped convex portions may be arranged in the y direction. However, in order to make the thickness of the air layer formed between the air discharge portion 28 and the rail 21 and the guide rail 22 constant, as shown in FIG. 4, the convex portion 41c is moved in the x direction and the y direction. It is desirable to arrange in two dimensions.

  Returning to the description of FIG. An iron bar-like member 26 is provided on the upper surface 11a of the surface plate 11 so that the longitudinal direction is along the x direction. A magnet 27 is provided on the lower surface 23 b of the plate-like portion 23. The rod-shaped member 26 and the magnet 27 are provided at opposing positions.

  The drive unit 25 is a linear motor having a stator 25a having a permanent magnet and a mover 25b having an electromagnetic coil. Two stators 25a and two movers 25b are provided.

  The stator 25a is a rod-shaped member having a substantially U-shaped cross section, and is provided such that the longitudinal direction is along the x direction. The stator 25a is provided at a line-symmetrical position around the guide rail 22. A pipe 25d through which a cooling liquid (for example, a fluorine-based inert liquid) flows is provided inside the stator 25a. For example, in the pipe 25d on the -z side, the coolant flows from the back side to the front side of the paper, and in the pipe 25d on the + z side, the coolant flows from the front side to the back side of the paper surface.

  The mover 25b is provided on the lower surface 23b of the plate-like portion 23 so that the electromagnetic coil is inserted into the stator 25a. The mover 25b has U-phase, V-phase, and W-phase coils (not shown) arranged in order, and moves along the stator 25a. A pipe 25c through which the coolant flows is provided inside the mover 25b so as to sew between the coils.

  Returning to the description of FIG. The position measuring unit 29 is, for example, a linear encoder, and measures the positional relationship between the surface plate 11 and the plate-like portion 23, that is, the position of the plate-like portion 23 in the x direction with respect to the origin position (described later in detail) of the position measuring portion 29. To do. The position measuring unit 29 is provided at both ends of the first moving unit 20 in the y direction (the + y side end and the −y side end). The position measuring unit 29 includes a scale 29a provided on the end surface on the + y side of the rail 21a and an end surface on the −y side of the rail 21b, and a detection head 29b provided on the end surface 23e and the end surface 23f of the plate-like portion 23. In FIG. 2, the scale 29a and the detection head 29b positioned on the + y side of the first moving unit 20 are not shown.

  The scale 29a is, for example, a laser hologram scale, and is configured to have a resolution of about 0.1 nm to 1 nm. The detection head 29b irradiates light (for example, laser light), and acquires the light reflected by the scale 29a. The position measuring unit 29 can obtain a clean sine wave (cosine wave) by forming a hologram on the scale 29a, thereby enabling high-accuracy interpolation and high resolution. Since the position measuring unit 29 is already known, detailed description thereof is omitted.

  The second moving unit 30 mainly moves the stage 41 along the two rails 31, the one guide rail 32, the convex portion 33 provided so as to sandwich the guide rail 32, and the upper surface of the rail 21. A drive unit 34 and a position measurement unit 39 are included.

  The two rails 31 and the guide rails 32 are elongated plate-like members made of ceramic, and are fixed to the upper surface 23a of the plate-like portion 23 along the y direction. The two rails 31 and the guide rail 32 have substantially the same height. The upper surfaces of the rail 31 and the guide rail 32 and the side surfaces of the guide rail 32 are formed with high accuracy and high flatness.

  The guide rail 32 is provided approximately at the center of the plate-like portion 23 in the x direction. The two rails 31 are provided at line symmetrical positions with the guide rail 32 interposed therebetween. The rail 31 a located at the −x side end of the two rails 31 is placed in a region in the vicinity of the end surface 41 h that is the −x side end of the stage 41, and the + x of the two rails 31 is + x. The region near the end surface 41i, which is the + x side end portion of the stage 41, is placed on the rail 31b located at the end on the side.

  FIG. 5 is a partially enlarged view of the second moving unit 30. On the lower surface 41b of the stage 41, a rod-shaped convex portion 33 is provided so that the longitudinal direction is along the x direction. By providing the convex portion 33 on the lower surface 41b, a groove 41g is formed on the lower surface 41b of the stage 41. The guide rail 32 is inserted into the groove 41g. This restricts the movement direction of the stage 41 so that the position of the stage 41 in the x direction, that is, the plate-like portion 23 does not move in any direction other than the y direction.

  The convex portion 33 is provided with an air discharge portion 33 a that discharges air toward the side surface of the guide rail 32. The opening of the air discharge part 33 a is exposed on the side surface of the convex part 33. The air discharge part 33a has an orifice with a narrowed inner diameter. Therefore, air supplied from a pump (not shown) or the like is discharged from this opening at high pressure and high speed. Thereby, an air layer is formed between the air discharge portion 33 a and the guide rail 32.

  A convex portion 41 c is formed on the lower surface 41 b of the stage 41 at a position facing the rail 31 and the guide rail 32. The protrusion 41c has a flat tip (surface facing the rail 31 or the guide rail 32). An air discharge portion 38 is provided on the convex portion 41c. The convex portion 41c and the air discharge portion 38 will be described in detail later.

  An iron bar member 36 is provided on the upper surface 23a of the plate-like portion 23 so that the longitudinal direction is along the x direction. A magnet 37 is provided on the lower surface 41 b of the stage 41. The rod-shaped member 36 and the magnet 37 are provided at opposing positions.

  The drive unit 34 is a linear motor having a stator 34a having a permanent magnet and a mover 34b having an electromagnetic coil. Two stators 34a and two movers 34b are provided. The stator 34a is provided in a line-symmetric position with the guide rail 32 as the center. The stator 34a has a pipe 34d through which the coolant flows, and the mover 34b has a pipe 34c through which the coolant flows. Since the stator 34a has the same configuration as the stator 25a, and the mover 34b has the same configuration as the mover 25b, a detailed description thereof will be omitted.

  Returning to the description of FIG. The position measuring unit 39 is, for example, a linear encoder, and measures the positional relationship between the plate-like unit 23 and the stage 41, that is, the position of the stage 41 in the y direction with respect to the origin position (described later in detail) of the position measuring unit 39. The position measuring unit 39 is provided at both ends of the second moving unit 30 in the x direction (end on the −x side and end on the + x side). The position measuring unit 39 includes a scale 39 a provided on the end surface on the −x side of the plate-like portion 23 (which may be the rail 31 a) and an end surface on the plate-like portion 23 (may be the rail 31 b) + x, an end surface 41 h of the stage 41 And a detection head 39b provided on the end face 41i. In FIG. 2, the scale 39a and the detection head 39b located on the + x side are not shown. The scale 39a is the same as the scale 29a, and the detection head 39b is the same as the detection head 29b.

The stage 41 is plate-shaped and has a substantially horizontal upper surface 41a and a lower surface 41b (see FIG. 7). The stage 41 is formed using a low expansion ceramic having a thermal expansion coefficient of approximately 0.5 to 1 × 10 ⁻⁷ / K. Thereby, deformation of the stage 41 can be prevented. The stage 41 can also be formed using an ultra-low expansion glass ceramic having a thermal expansion coefficient of approximately 5 × 10 ⁻⁸ / K. In this case, it is possible to reliably prevent the stage 41 from being deformed even if an uncontrollable temperature change occurs.

  A mask M (not shown) is placed on the upper surface 41a. The end face 41 h is provided with a biasing portion 45 that biases the mask M with a force in the + x direction and a biasing portion 46 that biases the mask M with a force in the + y direction. The urging units 45 and 46 are, for example, rotary cylinders. The urging portions 45 and 46 will be described in detail later.

  FIG. 6 is a schematic perspective view of the stage 41 as viewed obliquely from above. FIG. 7 is a schematic perspective view of the stage 41 as viewed obliquely from below.

  The stage 41 has a plurality of mask lifter holes 41d penetrating in the plate pressure direction. A rod-shaped mask lifter (not shown) is inserted into the mask lifter hole 41d. A mask lifter (not shown) is movable in the z direction and is used when the mask M is placed on the stage 41.

  A plurality of air holes 41e are two-dimensionally arranged on the upper surface 41a of the stage 41. The air holes 41e are provided every 20 mm to 50 mm. Air supplied from a pump (not shown) or the like is discharged upward (+ z direction) from the air hole 41e. Accordingly, the mask M placed on the upper surface 41a of the stage 41 can be temporarily levitated.

  Further, on the upper surface 41a of the stage 41, bar mirrors 41f are provided on two adjacent sides (here, the + x side and the -y side).

  Further, holes 41j, 41k, and 41l into which the pins 44a, 44b, and 44c are inserted are formed in the upper surface 41a of the stage 41. The pins 44a, 44b, and 44c are made of resin (for example, polyether ether ketone (PEEK)) and are rod-shaped members having a diameter of about 10 mm. The pins 44a, 44b, and 44c are frame bodies, respectively. 42, and can be moved in the y direction and the z direction by a pin driving unit 44d (see FIG. 11) and a moving mechanism (not shown).

  The pin driver 44d moves the pins 44a, 44b, 44c in the z direction, so that the positions where the pins 44a, 44b, 44c are inserted into the holes 41j, 41k, 41l, and the pins 44a, 44b, 44c into the holes 41j, The pins 44a, 44b, and 44c move between positions where the pins 44a, 44b, and 44c are separated from the stage 41 by being removed from the pins 41k and 41l. The position where the pins 44a, 44b and 44c are inserted into the hole 41j and the position where the pins 44a, 44b and 44c are inserted into the hole 41k as the pin drive unit 44d moves the pins 44a, 44b and 44c in the y direction. The pins 44a, 44b and 44c move between the positions where the pins 44a, 44b and 44c are inserted into the holes 41l. Various known techniques can be used for the configuration in which the pins 44a, 44b, and 44c are provided so as to be movable in the y direction and the z direction.

  The holes 41j, 41k, and 41l are selectively used depending on the size of the mask M. When the mask M of 800 mm × 520 mm is used, the pins 44 a, 44 b, 44 c are inserted into the holes 41 j, and when the mask M of 920 mm × 800 mm is used, the pins 44 a, 44 b, 44 c are inserted into the holes 41 k, When the mask M of 1400 mm × 1220 mm is used, the pins 44a, 44b and 44c are inserted into the holes 41l. As described above, the pins 44a, 44b, and 44c are detachably provided at positions where two adjacent sides of the mask M abut.

  The positions of the holes 41j, 41k, and 41l are formed at positions where the center of the stage 41 and the center of the mask M substantially coincide with each other when two adjacent sides of the corresponding mask M are in contact with each other.

  On the lower surface 41b of the stage 41, a plurality of convex portions 41c are formed two-dimensionally. The protrusion 41c has a flat tip (surface facing the rail 31 or the guide rail 32). A plurality of (for example, five) air discharge portions 38 are provided on the convex portion 41c. The air discharge part 38 has an air hole opened in the front end surface of the convex part 41c. Moreover, the air discharge part 38 has an orifice with a narrowed inner diameter. Therefore, air supplied from a pump (not shown) or the like is discharged from the air discharge unit 38 toward the rail 31 and the guide rail 32 at high pressure and high speed. Thereby, an air layer is formed between the air discharge part 38 and the rail 31 and the guide rail 32. Further, by providing a plurality of air discharge portions 38 on the convex portion 41c, the pressure of the air layer is increased.

  In the present embodiment, adjacent convex portions 41c are separated in both the x direction and the y direction, but the form of the convex portions 41c is not limited to this. For example, the convex portion may be a long rib shape along the y direction, and a plurality of rib-shaped convex portions may be arranged in the x direction. However, in order to make the thickness of the air layer formed between the air discharge portion 38 and the rail 31 and the guide rail 32 constant, as shown in FIG. 7, the convex portion 41c is moved in the x direction and the y direction. It is desirable to arrange in two dimensions.

  Returning to the description of FIG. The frame body 42 is provided on the upper surface 11 a of the surface plate 11, and holds the light irradiation unit 43 above the stage 41 (+ z direction). The frame body 42 has two pillars 42a and a beam 42b connecting the pillars 42a.

  The light irradiation unit 43 irradiates the mask M with light (in this embodiment, laser light). The light irradiation unit 43 is provided on the beam 42b at regular intervals (for example, approximately every 200 mm). In the present embodiment, there are seven light irradiation units 43a, a light irradiation unit 43b, a light irradiation unit 43c, a light irradiation unit 43d, a light irradiation unit 43e, a light irradiation unit 43f, and a light irradiation unit 43g. Since the light irradiation unit 43a to the light irradiation unit 43g have the same configuration, the light irradiation unit 43a will be described below.

  FIG. 8 is a perspective view showing a main part of the light irradiation part 43a. The light irradiation unit 43a mainly includes a frame body 431, a light source 432 provided inside the frame body 431, an objective lens 433 provided at the lower end of the frame body 431, an AF (autofocus) processing unit 435, Have Moreover, the light irradiation part 43a has a temperature adjusting part (not shown) that keeps the temperature inside the frame body 431 constant.

  The light source 432 is a light source that can be irradiated with a planar laser beam, and the pixels are two-dimensionally arranged. For example, a digital mirror device (Digital Mirror Device, DMD) can be used as the light source 432. The objective lens 433 focuses the laser light emitted from the light source 432 on the surface of the mask M.

  At the time of drawing, light is emitted from each of the light sources 432 of the light irradiation unit 43a to the light irradiation unit 43g, and this light is imaged on the mask M, whereby a pattern is drawn on the mask M.

  The AF processing unit 435 focuses the light irradiated on the mask M on the mask M, and mainly includes a tube lens group 435a, a beam splitter 435b, and two sensors 435c and 435d. As indicated by a two-dot chain line in FIG. 8, the laser light emitted from the light source 432 to the mask M is reflected by the mask M (not shown) and enters the beam splitter 435b through the objective lens 433 and the tube lens group 435a. To do. The reflected light is divided into two lights having different optical path lengths in the beam splitter 435b, and the two lights are received by different sensors 435c and 435d, respectively. The AF processing unit 435 performs autofocus processing for obtaining a focus position based on the results received by the sensors 435c and 435d. Since the autofocus process is already known, a description thereof will be omitted.

  The frame body 431 is provided on the beam 42b via the connecting portion 434. The surface 434a is fixed to the frame body 431, and the surface 434b is fixed to the beam 42b. The connecting portion 434 has a link mechanism that can move in the z direction while two parallel surfaces 434a and 434b are kept parallel by forming a hole 434c therein.

  The connecting portion 434 is provided with a piezo element 434d that moves the surface 434a in the z direction and a linear encoder 434e that measures the amount of movement of the surface 434a.

  Returning to the description of FIG. A pattern reading unit 47 that measures the position of the pattern drawn on the mask M is provided adjacent to the light irradiation unit 43. The pattern reading unit 47 includes seven pattern reading units 47a, a pattern reading unit 47b, a pattern reading unit 47c, a pattern reading unit 47d, a pattern reading unit 47e, a pattern reading unit 47f, and a pattern reading unit 47g. 47a-47g is provided adjacent to the light irradiation parts 43a-43g, respectively. Since the pattern reading units 47a to 47g have the same configuration, the pattern reading unit 47a will be described below.

  FIG. 9 is a perspective view showing an outline of the pattern reading unit 47a, and is a view seen through a main part. The pattern reading unit 47a mainly irradiates light (here, UV light) to the objective lens 471 that acquires an image (light) of the pattern P formed on the mask M (not shown in FIG. 9). A light source unit 472, a lens barrel 473 formed of a low thermal conductor such as titanium, zirconia, a tube lens 474 provided inside the lens barrel 473, and transmits light from the light source unit 472, and an objective lens A microscope having a mirror 475 that reflects light guided from 471, and a UV camera 476 that images a pattern acquired by the microscope.

  The light source unit 472 emits near ultraviolet rays (for example, light having a wavelength of about 375 nm). The light source unit 472 includes a light source 472a installed at a distance, an optical fiber 472b for guiding light from the light source, a diffusion plate 472c installed near the end face of the optical fiber, and a collimator lens 472d provided adjacent to the diffusion plate 472c, Have.

  The light source 472a is, for example, a UV laser or an sLED (Superluminous Light Emitting Diode) and irradiates laser light in the ultraviolet region. Since the light source 472a generates heat, the light source 472a is provided at a position away from the light irradiation unit 43. The light emitted from the light source 472a is guided using the optical fiber 472b. The diffusing plate 472c is guided by the optical fiber 472b and spreads the light of a point light source emitted from the end face of the optical fiber 472b, and the collimator lens 472d makes the light parallel light. Therefore, the light source unit 472 emits surface light source-like light.

  The light emitted from the light source unit 472 is reflected by the pattern P and guided to the objective lens “471. The objective lens 471 has a high magnification of about 100 times and a numerical aperture (NA) of about 0. 95. A UV lens having a characteristic of a focal length of about 2 mm The objective lens 471 is desirably provided adjacent to the objective lens 433 in order to read the pattern P formed by the light irradiation unit 43. Reference numeral 474 denotes a lens that forms an image of light from the objective lens 471 corrected for infinity, and has a focal length of approximately 200 mm.

  The UV camera 476 has a resolution of about SXGA (1280 × 1024 pixels), a size of about 1/4 inch, and a power consumption of about 0.1 W. The UV camera 476 can perform ultra-low speed scanning by the control unit 151a (see FIG. 12), and therefore can accurately read a fine pattern drawn on the mask M. In addition, it can be automatically shut down when not in use.

  Returning to the description of FIG. On the side surface on the −x side of the stage 41, an optical reading unit 48 that measures the position of the light (aerial image) i emitted from the light irradiation unit 43 is provided. The optical reading unit 48 includes seven optical reading units 48a, an optical reading unit 48b, an optical reading unit 48c, an optical reading unit 48d, an optical reading unit 48e, an optical reading unit 48f, and an optical reading unit 48g. Since the optical reading units 48a to 48g have the same configuration, the pattern reading unit 47a will be described below.

  FIG. 10 is a perspective view showing an outline of the optical reading unit 48a, and is a view seen through a main part. The optical reading unit 48a mainly includes an objective lens 481 that captures the light of the aerial image i, a mirror 482 that reflects light guided from the objective lens 481, a lens barrel 483 formed of a low thermal conductor, and a lens barrel 473. A microscope having a tube lens 484 provided therein, and a UV camera 485 that forms an image of a pattern obtained by the microscope. The objective lens 481, the mirror 482, the lens barrel 483, the tube lens 484, and the UV camera 485 have the same configurations as the objective lens 471, the mirror 285, the lens barrel 473, the tube lens 474, and the UV camera 476, respectively.

  The stage 41 is moved so that the light emitted from the light irradiation unit 43 enters the optical reading unit 48. The aerial image i irradiated from the objective lens 433 of the light irradiation unit 43 is enlarged by the objective lens 481, projected onto the UV camera 485, and the position thereof is read. The aerial image i preferably includes at least one line along the x direction and one line along the y direction in order to make the image position easy to read. FIG. 10 illustrates a cross pattern including one line along the x direction and one line along the y direction.

  Returning to the description of FIG. A laser interferometer 51 is provided on the column 42 a provided on the −y side. A laser interferometer 52 (not shown in FIG. 1) is provided on the side surface of the surface plate 11 on the + x side.

  FIG. 11 is a schematic diagram showing how the laser interferometers 51, 52, 53 measure. In FIG. 9, the laser beam path is indicated by a two-dot chain line. Moreover, in FIG. 9, the position of the light irradiation part 43a-light irradiation part 43g is shown with a dotted line.

  The laser interferometers 51, 52, and 53 emit four laser beams. Two of the four laser beams are reflected by the bar mirror 41f, and the reflected light is received by the laser interferometers 51 and 52.

  A mirror 436 is provided on the side surface of the light irradiation unit 43a on the -y side. The remaining two lights emitted from the laser interferometer 51 are reflected by the mirror 436, and the reflected light is received by the laser interferometer 51.

  A mirror 437 is provided on the side surface of the light irradiation unit 43a to the light irradiation unit 43g on the + x side. The remaining two of the light emitted from the laser interferometer 52 are reflected by the mirror 437 and the reflected light is received by the laser interferometers 52 and 53.

  The laser interferometers 52 and 53 are movable along the rail 11b by the drive unit 11c. The rail 11b is provided on the surface plate 11 so that the longitudinal direction is along the y direction. As described above, the laser interferometers 52 and 53 are movable in the y direction.

  The laser interferometer 52 on the −y side is provided at a position where light is irradiated on the light irradiation unit 43a at the time of drawing, and at the time of calibration (at the time of calibration), a position where light is irradiated on the light irradiation unit 43a, light irradiation The position 43b is moved in order, such as a position where light is irradiated to the portion 43b, a position where light is irradiated to the light irradiation portion 43c, and so on. The + y side laser interferometer 53 is always provided at a position where the light irradiation unit 43g is irradiated with light.

  The mirrors 436 and 437 are substantially parallel to the bar mirror 41f. Therefore, the laser interferometer 51 measures the position of the bar mirror 411 along the x direction of the bar mirror 41f using the mirror 436 as a reference position, and the laser interferometers 52 and 53 use the mirror 437 as a reference position. The position of the bar mirror 412 along the y direction of 41f is measured. In other words, the laser interferometer 51 measures the position of the stage 41 in the y direction with respect to the light irradiation unit 43 in the positional relationship between the light irradiation unit 43 and the stage 41 (position measuring units 29 and 39). The laser interferometers 52 and 53 measure the position of the stage 41 in the x direction with respect to the light irradiation unit 43 in the positional relationship between the light irradiation unit 43 and the stage 41 (position measurement units 29 and 39).

  Thus, the position of the bar mirror 41f measured by the laser interferometers 51, 52, and 53 exists in the first moving unit 20 and the second moving unit 30 because of errors due to pitching and yawing of the plate-like unit 23 and the stage 41. Does not include errors due to air layers. Therefore, in the present embodiment, the position interferometers 51, 52, and 53 are used to calibrate the position measuring units 29 and 39 that perform measurements including these errors, thereby increasing the mobility of the stage 41. The calibration of the position measuring units 29 and 39 will be described in detail later.

  The laser interferometers 51, 52, and 53 superimpose the light reflected by the mirror 436 or the mirror 437 and the light reflected by the bar mirror 41f, and measure the position by observing the wave interference. Accordingly, the wavelength of the laser beam changes depending on the atmospheric pressure, temperature, humidity, etc., and the measurement result may change even if the same position is measured. For this reason, the temperature, pressure, humidity, etc. are accurately measured to keep them constant, for example, a wavelength filter having a size of about 5 inches (125 mm) (for example, an etalon using multiple interference between two opposing reflecting surfaces) The wavelength of the laser beam may be monitored by measuring the interference state. Note that the etalon is desirably formed using a low expansion ceramic or an ultra low expansion glass ceramic as in the stage 41.

  When a laser interferometer light source capable of emitting eight or more laser beams (for example, twelve) is used as the laser interferometer 52, the laser interferometer 52 has a mechanism that moves along the y direction. You don't have to. The + y side laser interferometer 53 may not have a mechanism that moves along the y direction.

  FIG. 12 is a block diagram showing an electrical configuration of the mask manufacturing apparatus 1. The mask manufacturing apparatus 1 includes a CPU (Central Processing Unit) 151, a RAM (Random Access Memory) 152, a ROM (Read Only Memory) 153, an input / output interface (I / F) 154, and a communication interface (I / F). ) 155 and media interface (I / F) 156, which are driving units 25 and 34, position measuring units 29 and 39, light irradiation unit 43, biasing units 45 and 46, pattern reading unit 47, The optical reader 48 and the laser interferometers 51, 52, and 53 are connected to each other.

  The CPU 151 operates based on programs stored in the RAM 152 and the ROM 153, and controls each unit. Signals are input to the CPU 151 from the position measuring units 29 and 39, the laser interferometers 51 and 52, and the like. A signal output from the CPU 151 is output to the drive units 25 and 34 and the light irradiation unit 43.

  The RAM 152 is a volatile memory. The ROM 153 is a non-volatile memory in which various control programs and the like are stored. The CPU 151 operates based on programs stored in the RAM 152 and the ROM 153, and controls each unit. The ROM 153 stores a boot program executed by the CPU 151 when the mask manufacturing apparatus 1 is started, a program depending on the hardware of the mask manufacturing apparatus 1, and the like. Further, the ROM 153 stores drawing information, which is information related to the position and shape of the pattern drawn on the mask M, and correction substrate drawing information including information such as the position and shape of the correction substrate pattern. In this embodiment, since planar light is emitted from the light source 432, the drawing information associates the position of the light source 432 with the presence or absence of light irradiation (pattern presence or absence) in each pixel of the light source 432. Position information, the position of the light source 432, and irradiation timing information that associates the irradiation timing of light in each pixel of the light source 432 are included. The RAM 152 stores programs executed by the CPU 151, data used by the CPU 151, and the like.

  The CPU 151 controls an input / output device 141 such as a keyboard and a mouse via the input / output interface 154. The communication interface 155 receives data from other devices via the network 142 and transmits the data to the CPU 151, and transmits data generated by the CPU 151 to other devices via the network 142.

  The media interface 156 reads the program or data stored in the storage medium 143 and stores it in the RAM 152. Note that the storage medium 143 is, for example, an IC card, an SD card, a DVD, or the like.

  Note that a program for realizing each function is read from the storage medium 143, installed in the mask manufacturing apparatus 1 via the RAM 152, and executed by the CPU 151, for example.

  The CPU 151 has a function of a control unit 151a that controls each unit of the mask manufacturing apparatus 1 based on an input signal. The control unit 151a is constructed by executing a predetermined program read by the CPU 151. The processing performed by the control unit 151a will be described in detail later.

  The configuration of the mask manufacturing apparatus 1 shown in FIG. 12 has described the main configuration in describing the features of the present embodiment, and does not exclude, for example, the configuration of a general information processing apparatus. The constituent elements of the mask manufacturing apparatus 1 may be classified into more constituent elements according to the processing contents, or one constituent element may execute processing of a plurality of constituent elements.

  The operation of the mask manufacturing apparatus 1 configured as described above will be described. The following processing is mainly performed by the control unit 151a.

  First, using the laser interferometers 51, 52, and 53, calibration processing for calibrating the position measuring units 29 and 39 is performed.

  As already described, the measured values of the laser interferometers 51, 52, and 53 are accurate, but fluctuations occur in the downflow of clean air in the mask manufacturing apparatus 1. Further, the laser interferometers 51, 52 and 53 can only measure relative positions (the origin cannot be known).

  The measurement results of the position measuring units 29 and 39 are not affected by the downflow of clean air, but are present in the first moving unit 20 and the second moving unit 30 due to pitching and yawing errors of the plate-like unit 23 and the stage 41. Including errors due to air layers. Since the scales 29a and 39a are made of glass, the position measuring units 29 and 39 can accurately capture the change in distance in units of nm. An error may occur in the measurement.

  However, the position measuring units 29 and 39 usually have an origin signal (a signal indicating the origin position), and the reference point can be read with an accuracy equivalent to the resolution of the position measuring units 29 and 39. With this function, there is a possibility that the remaining drawing can be continued with good reproducibility even if the processing is stopped during the drawing process due to a data error or the like and the stage 41 needs to be returned to the origin position.

  Therefore, the relationship between the measurement values of the laser interferometers 51, 52, 53 and the measurement values of the position measurement units 29, 39 is examined in advance so that the measurement results of the position measurement units 29, 39 do not include errors, and the position measurement unit After performing calibration processing for calibrating 29 and 39, drawing processing is performed using the position measuring units 29 and 39.

  In the calibration process, the control unit 151a calculates a lookup table (LUT, Look up table) for each of the light irradiation units 43a to 43g. The LUT is an error table between the measurement values of the laser interferometers 51, 52, and 53 and the measurement values of the position measurement units 29 and 39. As shown in FIG. 21, the LUT includes LUTs 181a to 188a.

  As shown in FIG. 21, LUT 181a (LUT1) is a value used for correction of drawing information drawn by the light irradiation unit 43a in the x direction, and LUT 182a (LUT2) is x of drawing information drawn by the light irradiation unit 43b. LUT 183a (LUT3) is a value used for correction in the x direction of drawing information drawn by the light irradiation unit 43c, and LUT 184a (LUT4) is drawing information drawn by the light irradiation unit 43d. LUT185a (LUT5) is a value used for correction in the x direction of drawing information drawn by the light irradiation unit 43e, and LUT186a (LUT6) is drawn by the light irradiation unit 43f. The value is used for correcting the drawing information in the x direction, and the LUT 187a (LUT6) is used for correcting the drawing information drawn by the light irradiation unit 43g in the x direction. Is the value. The LUT 188a is a value used for correcting the drawing information drawn by the light irradiation units 43a to 43g in the y direction.

  First, calculation of the LUTs 181a and 187a will be described. The control unit 151a acquires the measurement value of the position measurement unit 29 located on the + y side and the measurement value of the position measurement unit 29 located on the −y side while moving the plate-like part 23 in the x direction. And the control part 151a is a measurement value when the position measurement part 29 assumes that it exists in the position of the y direction of the light irradiation part 43a or the light irradiation part 43g (measurement value in the position of the light irradiation part 43a or the light irradiation part 43g). ) Is calculated.

  When the position measurement unit 29 is assumed to be in the y direction position of the light irradiation unit 43a or the light irradiation unit 43g, the measurement value of the position measurement unit 29 located on the + y side and the position located on the −y side It is a weighted average value with the measurement value of the measurement unit 29. The weighted average value is the distance between the measured value of the position measurement unit 29 located on the + y side and the light irradiation unit 43a or the light irradiation unit 43g, and the position measurement unit 29 and the light irradiation unit 43a or the light irradiation located on the −y side. The average value is weighted according to the distance from the portion 43g. For example, if the distance between the position measurement unit 29 located on the + y side and the light irradiation unit 43a is a, and the distance between the position measurement unit 29 located on the −y side and the light irradiation unit 43a is b, the control unit 151a The value obtained by multiplying the measured value of the position measuring unit 29 located on the + y side by a / (a + b) and the value obtained by multiplying the measured value of the position measuring unit 29 located on the −y side by b / (a + b) are added. Then, the measurement value when the position measurement unit 29 is assumed to be at the position in the y direction of the light irradiation unit 43a is calculated. In addition, the position of the light irradiation part 43a (same also about 43b-43g) can be calculated from the design value (stored in ROM153) at the time of manufacturing the mask manufacturing apparatus 1.

  At the same time as the measurement using the position measurement unit 29, the control unit 151a uses the laser interferometer 52 to measure the change in the position in the x-axis direction when the position in the y direction is the position of the light irradiation unit 43a. Using the laser interferometer 53, a change in the position in the x-axis direction when the position in the y-direction is the position of the light irradiation unit 43g is measured.

  FIG. 13 shows measured values when the position measurement unit 29 is located in the y direction of the light irradiation units 43a and 43g when the plate-like portion 23 is moved in the x direction, and the laser interferometer 52, It is an example which compared the measurement result of 53. In FIG. 13, when the position measurement unit 29 is assumed to be at the y-direction position of the light irradiation unit 43a, the measured value is S1, and when the position measurement unit 29 is assumed to be at the y-direction position of the light irradiation unit 43g Let S2 be the measured value. The measurement result of the laser interferometer 52 is S52, and the measurement result of the laser interferometer 53 is S53.

  FIG. 13 shows that the measured values S1 and S2 are moving more excessively than the measured values S52 and S53, that is, the x-axis has a downward convex pitching. The pitch displacement amount, which is a quantity). The controller 151a compares the measurement value S1 with the measurement value S52 to create the LUT 181a, and compares the measurement value S2 with the measurement value S53 to create the LUT 187a.

FIG. 14 is a graph showing a correction value (LUT 181a) in the x direction when the measurement result shown in FIG. 13 is obtained. For example, the control unit 151a obtains a sequence ai (i is the x-axis position, and can take values every several nm, for example) in which the difference between the measured value S1 and the measured value S52 is arranged in the order of the x-axis position. . Then, the control unit 151a, i is the partial sum of the sequence ai when the _{0~x 0 (i = 0~x 0)} , the position of the x-axis is calculated as a correction value when an _{x 0.}

  In FIG. 13, when the plate-like portion 23 moves in the + x direction, it first rotates slightly to the right (clockwise in the xy plane), and then rotates to the left (counterclockwise in the xy plane). It turns out that it turns straight (moves along the x-axis). Thereby, a yaw displacement amount that is a displacement amount in the yawing direction can be calculated. This amount of yaw displacement is corrected by correction data generation processing using a correction substrate, which will be described in detail later.

  The control unit 151a acquires the measurement value of the position measurement unit 29 located on the + y side and the measurement value of the position measurement unit 29 located on the −y side while moving the plate-like part 23 in the x direction. The laser interferometer 52 measures the change in the position in the x-axis direction when the position in the y direction is the position of the light irradiation unit 43b. Then, similarly to the case of the light irradiation unit 43a, the control unit 151a calculates a measurement value when it is assumed that the position measurement unit 29 is at the position in the y direction of the light irradiation unit 43b. The LUT 182a is calculated by comparing with the measured value. The control unit 151a calculates the LUTs 183a to 186a by the same method for the light irradiation units 43c to 43f.

  The control unit 151 a calculates the correction value (LUT 188 a) of the position measurement unit 39 by the same method as the position measurement unit 29. The control unit 151a acquires the measurement value of the position measurement unit 39 located on the + x side and the measurement value of the position measurement unit 39 located on the −x side while moving the stage 41 in the y direction. At the same time, the laser interferometer 51 measures the change in the position in the y-axis direction when the position in the x direction is the position of the light irradiation unit 43a. Then, similarly to the case of the LUTs 181a to 187a, the control unit 151a calculates a measurement value when the position measurement unit 39 is assumed to be at the position in the x direction of the light irradiation unit 43a, and this is calculated by the laser interferometer 51. Compared with the measured value, LUT188a is calculated.

  The control unit 151a calibrates the position measurement units 29 and 39 by adding the correction values (LUTs 181a to 188a) calculated in this way to the measurement values of the position measurement units 29 and 39. The controller 151a uses the measured values of the position measuring units 29 and 39 after calibration in the subsequent processing.

  Subsequent to the calibration process, a correction substrate for correcting the light irradiation position and light irradiation timing from the light irradiation unit 43 and a correction data generation process using the correction substrate are performed.

  First, correction substrate creation processing will be described. First, a mounting process for mounting a mask M for forming a correction substrate on the stage 41 is performed. Hereinafter, the placement process will be specifically described.

  The mask M is placed on the mask lifter in a state where the controller 151a projects the mask lifter from the mask lifter hole 41d in the + z direction. When the mask M is placed on the mask lifter, the controller 151a moves the mask lifter in the −z direction while discharging air from the air hole 41e. As a result, the mask M is moved in the −z direction.

  Many air holes 41e are formed in the upper surface 41a, and air is discharged from all the air holes 41e with the same pressure. Therefore, when the mask lifter is pulled down into the mask lifter hole 41d, the mask M is evenly pushed up by the air, and the mask M is attached to the upper surface 41a via the air layer formed between the mask M and the upper surface 41a. Placed on the top. In this state, the control unit 151a drives the biasing units 45 and 46 to apply a horizontal force to the mask M, thereby positioning the mask M in the x direction and the y direction.

  FIG. 15 is a diagram illustrating a state in which the urging portions 45 and 46 press the mask M to perform positioning.

  The controller 151a drives the pin driver 44d to move the pins 44a, 44b, 44c in the -z direction, and inserts the pins 44a, 44b, 44c into any of the holes 41j, 41k, 41l. In FIG. 15, pins 44a, 44b, and 44c are inserted into the holes 41l.

  The urging portion 45 has an arm 45a, and a roller 45b is provided at the tip of the arm 45a. When the control unit 151a rotates the arm 45a clockwise about the shaft 45ax (see the arrow in FIG. 15), the roller 45b comes into contact with the end surface on the −x side of the mask M and applies a force in the + x direction to the mask M. Energize (see white arrow in FIG. 15). Since an air layer is formed between the mask M and the upper surface 41a, the mask M moves in the + x direction, and as a result, the mask M and the pins 44b and 44c come into contact with each other. Thereby, the mask M is positioned in the x direction. The urging unit 45 is preferably provided at a position where the roller 45b presses the approximate center of the mask M in the y direction. In order to make the distance between the arm 45a and the upper surface 41a constant, a roller (not shown) that contacts the upper surface 41a may be provided on the lower surface of the arm 45a.

  Like the urging portion 45, the urging portion 46 has an arm 46a, and a roller 46b is provided at the tip of the arm 46a. When the control unit 151a rotates the arm 46a counterclockwise about the shaft 46ax (see the arrow in FIG. 15), the roller 46b comes into contact with the end surface on the −y side of the mask M, and the force in the + y direction is applied to the mask M. (See the white arrow in FIG. 15). Since an air layer is formed between the mask M and the upper surface 41a, the mask M moves in the + y direction, and as a result, the mask M and the pin 44a come into contact with each other. Thereby, the mask M is positioned in the y direction. The urging unit 46 is desirably provided at a position where the roller 46b presses near the corners of the mask M in the −x direction and the −y direction. Further, in order to make the distance between the arm 46a and the upper surface 41a constant, a roller (not shown) that contacts the upper surface 41a may be provided on the lower surface of the arm 46a.

  When the pins 44a, 44b, 44c contact the mask M and the mask M is positioned in the horizontal direction, the controller 151a controls the stage 41 to stop the discharge of air from the air hole 41e. As a result, the mask M is placed on the upper surface 41a in a state where the positioning in the x direction and the y direction is performed. The controller 151a can determine that the pins 44a, 44b, 44c and the mask M are in contact with each other based on the detection result of a sensor (not shown) provided on the pins 44a, 44b, 44c.

  Thereafter, the control unit 151a controls the pin driving unit 44d to move the pins 44a, 44b, 44c in the + z direction, and removes the pins 44a, 44b, 44c from any of the holes 41j, 41k, 41l. 44a, 44b and 44c are separated from the stage 41. Thereby, the mask M can be positioned with high accuracy.

  Since the mask M is placed on the upper surface 41a, the mask M is fixed to the upper surface 41a by friction between the upper surface 41a and the lower surface of the mask M. Therefore, after the mask M is placed on the upper surface 41a, even if the pins 44a, 44b, and 44c move in the + z direction, for example, the mask M is not deformed or moved unless the stage 41 is deformed. No. Further, since the pins 44a, 44b and 44c are removed from the holes 41j, 41k and 41l, the mask M comes into contact with the pins 44a, 44b and 44c and the mask M receives a force from the pins 44a, 44b and 44c. It is possible to prevent M from being distorted.

  When the mask M is placed on the stage 41, the control unit 151a draws a correction substrate pattern on the mask M to generate a correction substrate. The control unit 151a acquires correction substrate drawing information, which is information related to the correction substrate pattern, from the ROM 153, and performs drawing processing based on the correction substrate drawing information. The process of irradiating the mask M with light can be performed using a known technique.

  FIG. 16 is a diagram illustrating an example of correction board drawing information. In FIG. 16, the position of the mask M is schematically shown by a dotted line. The correction substrate pattern is a pattern including a plurality of crosses arranged in a two-dimensional shape, and is a lattice pattern in the present embodiment. The control unit 151a generates the correction substrate M1 by drawing the correction substrate pattern on the mask M while moving the stage 41 in the x and y directions by controlling the driving units 25 and 34. The controller 151a moves the stage 41 in the x direction to perform drawing for one row, and then moves the stage 41 in the y direction to perform the correction substrate drawing process. The process of moving the stage 41 will be described in detail later.

  FIG. 17 shows a correction substrate M1 generated based on the correction substrate drawing information shown in FIG. In FIG. 17, the pattern of region A1 is drawn by the light irradiation unit 43a, the pattern of region A2 is drawn by the light irradiation unit 43b, and the pattern of region A3 is drawn by the light irradiation unit 43c. The pattern of A4 is drawn by the light irradiation unit 43d, the pattern of the region A5 is drawn by the light irradiation unit 43e, the pattern of the region A6 is drawn by the light irradiation unit 43f, and the pattern of the region A7 is light It is drawn by the irradiation unit 43g. In FIG. 17, due to various errors, the drawing pattern in the x direction is a curve bulged by y1 on the right side (−y direction) in FIG.

  Next, the control unit 151a generates correction data for correcting an installation error or the like of the light irradiation unit 43 using the correction substrate M1. Hereinafter, a method for generating correction data will be described in detail.

  The control unit 151a includes an initial state (0 degree) that is a state when the correction substrate M1 is generated, and a state in which the correction substrate M1 is rotated by approximately 90 degrees, approximately 180 degrees, and approximately 270 degrees from the initial state. In each state, the correction substrate M1 is placed on the upper surface 41a of the stage 41. In each case, the correction substrate M1 is read using the pattern reading unit 47.

  In the initial state, the pattern of the area A1 is read by the pattern reading unit 47a, the pattern of the area A2 is read by the pattern reading unit 47b, the pattern of the area A3 is read by the pattern reading unit 47c, and the pattern of the area A4 is the pattern. The pattern is read by the reading unit 47d, the pattern of the region A5 is read by the pattern reading unit 47e, the pattern of the region A6 is read by the pattern reading unit 47f, and the pattern of the region A7 is read by the pattern reading unit 47g. Therefore, the result of reading the correction substrate M1 using the pattern reading unit 47 coincides with the correction substrate drawing information shown in FIG.

  FIG. 18 shows a result of reading the correction substrate M1 using the pattern reading unit 47 in a state where the correction substrate M1 is rotated approximately 180 degrees from the initial state. In this case, the pattern of the area A1 is read by the pattern reading unit 47g, the pattern of the area A2 is read by the pattern reading unit 47f, the pattern of the area A3 is read by the pattern reading unit 47e, and the pattern of the area A4 is read by the pattern The pattern is read by the reading unit 47d, the pattern of the region A5 is read by the pattern reading unit 47c, the pattern of the region A6 is read by the pattern reading unit 47b, and the pattern of the region A7 is read by the pattern reading unit 47a. Therefore, the result of reading the correction substrate M1 rotated approximately 180 degrees from the initial state by the pattern reading unit 47 (see the solid line in FIG. 18) indicates that the drawing pattern in the x direction is y2 on the left side (+ y direction) in FIG. It becomes only a puffy curve. y2 is twice as large as y1. In FIG. 18, broken lines indicate correction board drawing information.

  The control unit 151a reads the reading result in the initial state (correction substrate drawing information, see the dotted line in FIG. 18) and the reading result in the state where the correction substrate M1 is rotated approximately 180 degrees from the initial state (solid line in FIG. 18). The middle of the reference (refer to the two-dot chain line in FIG. 18) is set as the correction value of the light irradiation unit 43.

  In the case shown in FIG. 18, the correction value is a curve in which the drawing pattern in the x direction is expanded by y1 in the + y direction. When the correction substrate M1 ′ (not shown) is drawn using information obtained by adding the correction value to the correction substrate drawing information, the pattern of the correction substrate M1 ′ becomes a straight line, and is read by the pattern reading unit 47 in the initial state. The reading result and the reading result by the pattern reading unit 47 in a state where the correction substrate M1 ′ is rotated approximately 180 degrees from the initial state coincide with each other.

  Similarly, the control unit 151a reads the reading result by the pattern reading unit 47 when the correction substrate is rotated by approximately 90 degrees from the initial state, and the pattern when the correction substrate is rotated by approximately 270 degrees from the initial state. The middle of the reading result by the reading unit 47 is calculated as a correction value.

  In this way, the control unit 151a sets the correction substrate M1 to approximately 90 degrees, approximately 180 degrees, and approximately 270 degrees from the initial state (0 degrees), which is the state when the correction substrate M1 is generated. The position of the correction substrate pattern when the correction substrate M1 is read in each of the rotated states is acquired, the read result in the initial state, and the state in which the correction substrate M1 is rotated by approximately 180 degrees The read value obtained when the correction substrate M1 is rotated approximately 90 degrees coincides with the read result obtained when the correction substrate M1 is rotated approximately 270 degrees. Is the correction data of the light irradiation unit 43. Note that these read values match only when the pattern drawn on the correction substrate M1 completely matches the pattern shown in the correction substrate drawing information.

  Thereby, the light irradiation unit 43 alone can calibrate itself, and the pattern drawn on the mask M can be completely matched with the pattern shown in the drawing information. Further, by using a correction substrate pattern including a plurality of cross positions, correction values can be obtained for each of the x direction and the y direction. In this embodiment, the control unit 151a performs the creation of the correction substrate and the correction data generation process using the correction substrate once, but the creation of the correction substrate and the correction substrate are used. The correction data generation processing that has been performed may be performed a plurality of times. In the present embodiment, the control unit 151a matches the reading result in the initial state with the reading result in the state where the correction substrate M1 is rotated by approximately 180 degrees, and the correction substrate M1 is approximately 90%. The correction value for the light irradiation unit 43 is a correction value that matches the reading result obtained when the correction substrate M1 is rotated by approximately 270 degrees and the reading result obtained when the correction substrate M1 is rotated approximately 270 degrees. A value in which the result and the reading result obtained when the correction substrate M1 is rotated approximately 180 degrees may be used as the correction data.

  Next, the drawing process will be described. First, a placement process for placing the mask M on the stage 41 is performed. Since the mounting process is the same as that for generating the correction substrate M1, the description thereof is omitted.

  When the mask M is placed on the stage 41, the control unit 151a leaves the mask M as it is until a predetermined time (for example, several hours) elapses. Thereafter, the control unit 151a controls the AF processing unit 435 to acquire distance information in which the position of the mask M and the distance between the light irradiation unit 43 and the mask M are associated, and correction information based on the distance information. (Xy correction table) is created (used for drawing position correction processing to be described in detail later).

  FIG. 19 is a schematic diagram showing a state of the mask M when dust D is adhered between the mask M and the upper surface 41 a of the stage 41. When the mask M is bent by the dust D, the position where the mask M is to be applied when the vertical laser beam is irradiated from the light irradiation units 43a to 43g on the assumption that the photosensitive substrate is not bent. An error occurs between the position where the laser beam actually hits when it is bent.

  For example, in the portion where the center line of the mask M (see the alternate long and short dash line in FIG. 19) is convex upward (+ z side), the surface of the mask M extends. Must be bigger. On the other hand, in the portion where the center line of the mask M is convex downward (−z side), since the surface of the mask M is contracted, the amount of movement in the y direction must be reduced during the drawing process. .

  Further, even when the thickness of the mask M is not uniform, an error occurs between the position where the laser beam is applied from the light irradiation units 43a to 43g and the position where the laser beam actually hits. Therefore, the control unit 151a acquires the thickness distribution (total thickness variation, TTV) of the mask M as the distance information.

  As described above, the control unit 151a corrects the drawing information by creating an xy correction table in which the position of the mask M and the horizontal displacement of the mask M are associated with each other based on the acquired distance information.

  In addition, the control unit 151a acquires the positional relationship of the light irradiation units 43a to 43g using the light reading units 48a to 48g. First, the control unit 151a moves the stage 41 so that the positions of the light irradiation units 43a to 43g on the xy plane coincide with the positions of the light reading units 48a to 48g on the xy plane. And the control part 151a irradiates light from the light irradiation parts 43a-43g, the aerial image i irradiated from the light irradiation part 43a is read by the light reading part 48a, and the aerial image i irradiated from the light irradiation part 43b is read. The aerial image i read by the light reading unit 48b and read from the light irradiation unit 43c is read by the light reading unit 48c, the aerial image i irradiated from the light irradiation unit 43d is read by the light reading unit 48d, and the light irradiation unit 43e The irradiated aerial image i is read by the light reading unit 48e, the aerial image i irradiated from the light irradiation unit 43f is read by the light reading unit 48f, and the aerial image i irradiated from the light irradiation unit 43g is read by the light reading unit 48g. read. The control unit 151a converts the results read by the optical reading units 48a to 48g into the x-coordinate and y-coordinate positions, respectively.

  Next, the control unit 151a moves the stage 41 in the -y direction, reads the aerial image i irradiated from the light irradiation unit 43b with the light reading unit 48a, and reads the aerial image i irradiated from the light irradiation unit 43c. The aerial image i read by the light reading unit 48b, irradiated from the light irradiation unit 43d, is read by the light reading unit 48c, the aerial image i irradiated from the light irradiation unit 43e is read by the light reading unit 48d, and the light irradiation unit 43f The irradiated aerial image i is read by the light reading unit 48e, and the aerial image i irradiated from the light irradiation unit 43g is read by the light reading unit 48f. The control unit 151a converts the results read by the optical reading units 48a to 48f into the x-coordinate and y-coordinate positions, respectively.

  The control unit 151a compares the light reading unit 43a and the light by comparing the result read at the first time (the position of the x coordinate and the y coordinate) with the result read at the second time (the position of the x coordinate and the y coordinate). Positional relationship with the irradiation unit 43b, positional relationship between the light irradiation unit 43b and the light irradiation unit 43c, positional relationship between the light irradiation unit 43c and the light irradiation unit 43d, positional relationship between the light irradiation unit 43d and the light irradiation unit 43e, The positional relationship between the light irradiation unit 43e and the light irradiation unit 43f and the positional relationship between the light irradiation unit 43f and the light irradiation unit 43g are respectively acquired. The accuracy of the position measurement is approximately 10 nm or less, although it is based on the magnification of the microscope of the light irradiation unit 43 and the like. The control unit 151a corrects the drawing information using these positional relationships.

  Next, based on the measurement values acquired by the position measurement units 29 and 39, the control unit 151a moves to a position where the light irradiation unit 43a irradiates light to the −x side end and the −y side end of the mask M. The stage 41 is moved. Thereafter, the control unit 151a performs the drawing process by moving the stage 41 while irradiating light from the light irradiation unit 43. The controller 151a obtains drawing information from the ROM 153 prior to the drawing process. Then, the control unit 151a corrects the drawing information based on the calculated correction value, and performs a drawing process using the corrected drawing information.

  First, the movement of the stage 41 in the drawing process will be described. The control unit 151a continuously discharges air from the air discharge units 28 and 38 during the drawing process. As a result, an air layer is formed between the plate-like portion 23 and the rail 21 and the guide rail 22, so that the plate-like portion 23 moves smoothly on the rail 21 and the guide rail 22. In addition, since an air layer is formed between the stage 41 and the rail 31 and the guide rail 32, the stage 41 moves smoothly on the rail 31 and the guide rail 32. Thereby, the stage 41 can be smoothly moved in the horizontal direction (x direction and y direction). In particular, the projections 23c and the projections 41c are arranged two-dimensionally, and the air layer has a constant thickness, so that the plate-like portion 23 and the stage 41 can be moved horizontally without changing the height of the stage 41. Can be moved.

  The rod-like member 26 is attracted by the magnet 27 while discharging air from the air discharge portion 28 to form an air layer between the plate-like portion 23 and the rail 21 or the guide rail 22. The portion 23 is prevented from floating too much from the rail 21 or the guide rail 22. Further, the rod-shaped member 36 is attracted to the magnet 37 while discharging air from the air discharge portions 28 and 38 to form an air layer between the stage 41 and the rail 31 or the guide rail 32. The stage 41 is prevented from floating too much from the rail 31 or the guide rail 32. Thereby, the fluctuation | variation of the height of the plate-shaped part 23 or the stage 41 can be prevented. Further, by providing the plurality of air discharge portions 28 and 38 on the convex portions 23c and 41c, respectively, an air layer formed between the plate-like portion 23 and the rail 21 or the guide rail 22, and the stage 41 and the rail The pressure of the air layer formed between 31 and the guide rail 32 can be increased, and thereby the rigidity of the plate-like portion 23 and the stage 41 can be increased.

  Further, the rod-like member 26 is attracted by the magnet 27, so that the air layer formed between the plate-like portion 23 and the rail 21 or the guide rail 22 is thinned, thereby increasing the pressure of the air layer. Thus, the rigidity of the plate-like portion 23 can be increased. Further, by attracting the rod-shaped member 36 to the magnet 37, the air layer formed between the stage 41 and the rail 31 or the guide rail 32 is thinned, thereby increasing the pressure of the air layer, The rigidity of the stage 41 can be increased.

  Since the drive unit 25 is provided in the vicinity of the guide rail 22 at a line-symmetrical position with the guide rail 22 as the center, the drive unit 25 does not rotate the plate-like portion 23 (stage 41) in the horizontal plane. The shaped portion 23 (stage 41) can be moved in the x direction. Further, since the drive unit 34 is provided in the vicinity of the guide rail 32 at a line-symmetrical position around the guide rail 32, the drive unit 34 moves the stage 41 in the y direction without rotating the stage 41 in the horizontal plane. Can be moved to.

  Further, when moving the stage 41, the control unit 151 a controls the drive unit 25 based on the information acquired from the position measurement unit 29 and controls the drive unit 34 based on the information acquired from the position measurement unit 39. FIG. 20 is a diagram illustrating the control of the drive units 25 and 34 performed by the control unit 151a.

  First, the thrust converters 164 and 174 output signals to the U phase, the V phase, and the W phase of the movers 25b and 34b, respectively, and the thrust converters 164 and 174, based on the results, The power factors (power factor information) of the U phase, V phase, and W phase are obtained in advance.

  The measurement signal in the position measuring unit 29 on the −y side of the first moving unit 20 is input to the X counter (1) 161, and the measurement signal in the position measuring unit 29 on the + y side is input to the X counter (2) 162. The The control unit 151a sets the average value of the output of the X counter (1) 161 and the output of the X counter (2) 162 as the current position.

  The target coordinate calculation unit 163 calculates the current target coordinates (position command) based on the pulse output from the CPU 151 and the like. The control unit 151a calculates a linear function (P) of a deviation between the output signals from the X counter (1) 161 and the X counter (2) 162 and the position command output from the target coordinate calculation unit 163. Further, the control unit 151a calculates an input value (I) that changes in proportion to the integral of the deviation and an input value (D) that changes in proportion to the derivative of the deviation. These values are input to the thrust converter 164.

  Further, the control unit 151a calculates a primary differential term for first-order differentiation of the position command calculated by the target coordinate calculation unit 163 and a secondary differential term for second-order differentiation of the position command. These values are input to the thrust converter 164. An origin signal serving as a reference for managing the position of the drive unit 25 from the origin sensor 165 is input to the thrust conversion unit 164.

  The thrust converting unit 164 generates a signal for driving the driving unit 25 based on the input information. Specifically, the thrust conversion unit 164 is based on PID control that combines proportional operation, integration operation, and differentiation operation, and a position command, a primary differential term, and a secondary differential term input from the target coordinate calculation unit 163. Feed-forward control. Then, the thrust converter 164 generates a drive signal based on the control result, power factor information, and the like. The drive signal is a signal corresponding to each of the U phase, the V phase, and the W phase. After being amplified by the amplifiers 166, 167, and 168, the drive signal is applied to each of the U phase, V phase, and W phase coils of the mover 25b. Is output. Therefore, the stage 41 can be accurately moved. In order to perform highly accurate control (control in units of nm to several tens of nm), the amplifiers 166, 167, and 168 are desirably DC linear amplifiers.

  The measurement signal in the position measuring unit 39 on the −x side of the second moving unit 30 is input to the Y counter (1) 171, and the measurement signal in the position measuring unit 39 on the + x side is input to the Y counter (2) 172. The The controller 151a sets the average value of the output of the Y counter (1) 171 and the output of the Y counter (2) 172 as the current position.

  The target coordinate calculation unit 173 calculates a position command similarly to the target coordinate calculation unit 163. The control unit 151a calculates a linear function (P) of a deviation between the output signals from the Y counter (1) 171 and the Y counter (2) 172 and the position command output from the target coordinate calculation unit 173. Further, the control unit 151a calculates an input value (I) that changes in proportion to the integral of the deviation and an input value (D) that changes in proportion to the derivative of the deviation. These values are input to the thrust converter 174.

  Further, the control unit 151a calculates the first derivative term of the position command calculated by the target coordinate calculation unit 173 and the second derivative term of the position command. These values are input to the thrust converter 174. An origin signal serving as a reference for managing the position of the drive unit 34 from the origin sensor 175 is input to the thrust conversion unit 174.

  The thrust conversion unit 174 generates a signal for driving the drive unit 25 based on the input information. Specifically, the thrust conversion unit 174 performs PID control and feedforward control similarly to the thrust conversion unit 164, and generates a drive signal based on the control result, power factor information, and the like. The drive signal is a signal corresponding to each of the U phase, the V phase, and the W phase. After being amplified by the amplifiers 176, 177, and 178, the drive signal is applied to each of the U phase, V phase, and W phase coils of the mover 34b. Is output. Therefore, the plate-like portion 23 can be accurately moved. As with the amplifiers 166, 167, and 168, the amplifiers 176, 177, and 178 are desirably DC linear amplifiers.

  In addition, the control unit 151 a controls the drive unit 34 so that the stage 41 does not protrude from the plate-like part 23 when the stage 41 is moved. Further, the control unit 151 a controls the driving unit 25 so that the plate-like portion 23 does not protrude from the rail 21 and the guide rail 22 when the plate-like portion 23 is moved. Thereby, it is possible to prevent the holding position of the mask M from being shifted due to the deflection of the stage 41.

  Next, control of the light irradiation unit 43 in the drawing process will be described. FIG. 21 is a diagram illustrating the drawing position correction process performed by the control unit 151a. The LUTs 181a to 188a have already been obtained by the calibration process. The LUTs 181a to 188a do not need to be updated unless the travel conditions of the stage 41 change, such as changing the scales 29a and 39a, or changing the pressure of the air discharged from the air discharge units 28 and 38. The LUTs 181a to 187a may include values for correcting the positional relationship of the light irradiation units 43a to 43g obtained by the light reading units 48a to 48g.

  Based on the correction data using the correction substrate M1 and the xy correction table described above, the control unit 151a performs the x-direction offset tables 181b to 187b and the y-direction offset tables 188b to 188h based on the light irradiation units 43a to 43g. Is calculated. Since the correction data and the xy correction table are data associated with the position on the mask M, the control unit 151a adds, for example, the correction data at the position p (not shown) on the mask M and the xy correction table. Thus, the offset amount in the x direction and the offset amount in the y direction at the position p are calculated. Then, the control unit 151a performs this process on all positions on the mask M, and divides the result according to the position of the mask M drawn by each of the light irradiation units 43a to 43g, thereby offsetting in the x direction. Tables 181b to 187b and y-direction offset tables 188b to 188h are calculated. The offset tables 181b to 187b and 188b to 188h are steady values. The offset tables 181b to 187b and 188b to 188h are two-dimensionally arranged corresponding to each pixel of the light source 432 for each position of the light irradiation units 43a to 43g.

  The control unit 151a drives the drive units 25 and 34 based on the drive signals generated based on the PID control and the feedforward control in the thrust conversion units 164 and 174, and the plate-like unit 23 by the position measurement units 29 and 39. The position in the x direction and the position in the y direction of the stage 41 are measured. Then, these values are weighted and added according to the positions of the respective light irradiation units 43a to 43g, so that the positions 191 to 197 in the x direction of the light irradiation units 43a to 43g at the present time and the y direction of the light irradiation unit 43a at the current time point. The position 198 is calculated. The calculation of the positions 191 to 198 by weighted addition is performed by the same method as the calculation of the measurement values when it is assumed that the position measurement units 29 and 39 are at the positions of the light irradiation units 43a to 43g.

  Since the measured values of the position measuring units 29 and 39 each include the yaw displacement amount, the y-direction position 198 needs to be calculated by adding the rotation amount obtained from the measured values of the position measuring units 29 and 39. .

  When the control unit 151a acquires the position 191 in the x direction of the light irradiation unit 43a, the control unit 151a acquires a correction value at the position 191 from the LUT 181a and the offset table 181b, and adds the value in the x direction of the light irradiation unit 43a. Calculated as a pattern position correction amount. Similarly, the control unit 151a acquires the correction values at the positions 192 to 197 from the LUTs 182a to 187a and the offset tables 182b to 187b based on the positions 192 to 197 in the x direction of the light irradiation units 43b to 43g. Are added as pattern position correction amounts in the x direction of the light irradiation units 43b to 43g, respectively.

  Further, when the control unit 151a acquires the position 198 in the y direction of the light irradiation unit 43a, the control unit 151a acquires a correction value at the position 191 from the LUT 188a and the offset table 188b, and adds the value to the y value of the light irradiation unit 43a. Calculated as the pattern position correction amount in the direction. Similarly, the control unit 151a calculates pattern position correction amounts in the y direction of the light irradiation units 43b to 43g based on the LUT 188a and the offset tables 188c to 188h, respectively.

  The control unit 151a corrects the drawing information using the calculated pattern position correction amount in the x direction and the pattern position correction amount in the y direction. Specifically, as illustrated in FIG. 22 or FIG. 23, the control unit 151 a performs position correction in the x direction and the y direction by moving an optical member included in the light irradiation unit 43.

  22 and 23 are schematic views showing a state in which the position (image position) where the light emitted from the light source 432 is imaged is moved in the horizontal direction. 22 and 23, the light path when the optical member is not moved is indicated by a thin solid line, and the light path when the optical member is moved is indicated by a thin two-dot chain line. 22 and 23, for the sake of explanation, only the light emitted from a certain point among the planar light emitted from the light source 432 is illustrated.

  As shown in FIG. 22, the image position is moved in the horizontal direction by moving the tube lens group 435a in the horizontal direction (x direction and / or y direction). In FIG. 22, as a result of moving the tube lens group 435a from the position indicated by the solid line to the position indicated by the two-dot chain line, the image position is moved in the -y direction. In addition, aberration is suppressed by adopting a configuration in which only the tube lens group 435a is moved in the horizontal direction.

  Further, as shown in FIG. 23, by tilting the parallel plate 439 with respect to the x direction and / or the y direction, the apparent light emission point is moved in the horizontal direction, and the image position is moved in the horizontal direction. In FIG. 23, by tilting the parallel plate 439 around the y correction rotation axis so that the right side in FIG. 23 faces downward, the apparent light emission point becomes the left side in FIG. 23 (the dotted line from the position indicated by the solid line in FIG. 23). The image position is moved to the right side (−y direction) in FIG. Further, the image position is moved in the x direction by rotating the parallel plate 439 around the x correction rotation axis. It is desirable that the parallel plate 439 has an inclination of approximately 1 to 2 degrees or less in order to suppress aberration.

  As described above, when the surface of the laser beam is irradiated by moving the tube lens group 435a in the horizontal direction or by tilting the parallel plate 439, the drawing information is corrected and the light is irradiated. can do.

  The controller 151a may perform the position correction in the x direction by shifting the timing of lighting each pixel of the light source 432, that is, the irradiation timing information (the output timing of the Horizontal Drive signal). In addition, for the position correction in the y direction, the control unit 151a moves the drawing information using redundant pixels provided outside the drawing information (two-dimensionally arranged pixels) of the light source 432, that is, shifts the position information. May be performed.

  As described above, the control unit 151a corrects the drawing information according to the current positions of the light irradiation units 43a to 43g, and performs the drawing process based on the corrected drawing information. In the drawing process, the control unit 151a moves the stage 41 in the x direction and draws one row, and then moves the stage 41 in the y direction. The control unit 151a moves the frame body 431 in the z direction as necessary during the drawing process. The movement of the frame 431 is performed by driving the piezo element 434d while measuring the amount of movement of the frame 431 in the z direction by the linear encoder 434e. Thereby, even if the thickness of the mask M fluctuates, the light emitted from the light irradiation unit 43 can be imaged on the mask M.

  According to the present embodiment, since the position measuring units 29 and 39 are calibrated using the laser interferometers 51, 52, and 53, the stage can be accurately moved in the horizontal direction. Therefore, the position accuracy of the pattern drawn on the mask M can be increased.

  In addition, according to the present embodiment, since the correction substrate is generated using the light irradiation unit 43, the correction data is generated using the correction substrate, and the drawing information is corrected using the correction data, the light irradiation is performed. The pattern can be accurately drawn by correcting the installation error of the unit 43 and the like.

Further, according to the present embodiment, the AF processing unit 435 is controlled to acquire a change in the height direction such as the deflection of the mask M, and an xy correction table is created to correct this, and the xy correction table is used. Since the drawing information is corrected, the pattern can be drawn accurately even when the mask M is bent. Further, by forming the stage 41 using a ceramic having a thermal expansion coefficient of approximately 1 × 10 ⁻⁷ / K or less (smaller than the thermal expansion coefficient of the mask M), a temperature change that cannot be controlled (about 0.01 degrees). ), The deformation of the stage 41 can be prevented, and the deflection (deflection due to expansion and contraction) of the mask M caused thereby can be prevented, and the pattern position accuracy can be increased.

  Further, according to the present embodiment, an air layer is formed between the air discharge unit 28 and the rail 21 and the guide rail 22 and between the air discharge unit 38 and the rail 31 and the guide rail 32. The stage 41 can be moved smoothly and accurately, thereby increasing the position accuracy of the pattern. In addition, an air layer is formed between the guide rail 22 and the groove 23d, and an air layer is formed between the guide rail 32 and the groove 41g. This is effective for accurately moving the pattern and thereby increasing the position accuracy of the pattern.

  In this embodiment, a pipe 25c through which the coolant flows is provided inside the mover 25b, and a pipe 34c through which the coolant flows is provided inside the mover 34b. However, the pipes 25c, 25d, 34c, and 34d are Not required. Further, the method of cooling the movers 25b and 34b and the stators 25a and 34a is not limited to this.

  In the present embodiment, the rod-like member 26 and the magnet 27 are provided between the surface plate 11 and the plate-like portion 23, and the rod-like member 36 and the magnet 37 are provided between the plate-like portion 23 and the stage 41. Although the air layer formed between the stage 41 and the rail 31 or the guide rail 32 is thinned, the method of thinning these air layers is not limited to this. For example, an air suction part for sucking air may be further provided on the convex part 23c of the plate-like part 23A, and an air suction part for sucking air may be further provided on the convex part 41c of the stage 41. Moreover, the structure which makes thin the air layers, such as the rod-shaped member 26, the magnet 27, the rod-shaped member 36, the magnet 37, and an air suction part, is not essential.

  In the present embodiment, seven light irradiation units 43 are provided, but the number of light irradiation units 43 is not limited to seven and may be one. However, in order to reduce the amount of movement in the y direction, it is desirable to provide a plurality of light irradiation units 43.

  In the present embodiment, the pattern reading unit 47 is provided separately. However, if the function of the pattern reading unit 47 can be included in the light irradiation unit 43, the pattern reading unit 47 does not need to be provided separately. Further, a part of the function of the pattern reading unit 47 may be included in the light irradiation unit 43. That is, the pattern reading unit 47 may be provided adjacent to the light irradiation unit 43 or may be provided in the light irradiation unit 43.

  In the present embodiment, the pins 44a, 44b, 44c are provided so as to be movable with respect to the frame body 42, and the pins 44a, 44b, 44c are inserted into any of the holes 41j, 41k, 41l as necessary. Thus, the pins 44a, 44b, and 44c are provided on the stage 41. However, the pins 44a, 44b, and 44c may be provided on the stage 41 in advance. However, in order to prevent the mask M from being distorted due to the mask M constantly contacting the pins 44a, 44b, 44c, the pins 44a, 44b, 44c are removed from the stage 41 after the mask M is placed on the stage 41. It is desirable. Further, the form in which the pins 44a, 44b, 44c are inserted into or removed from the holes 41j, 41k, 41l is not limited to this.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included. . A person skilled in the art can appropriately change, add, or convert each element of the embodiment.

  Further, in the present invention, “substantially” is a concept including not only a case where they are exactly the same but also errors and deformations that do not lose the identity. For example, “substantially horizontal” is not limited to being strictly horizontal, but is a concept including an error of about several degrees, for example. Further, for example, when simply expressing as parallel, orthogonal, etc., not only strictly parallel, orthogonal, etc. but also cases of substantially parallel, substantially orthogonal, etc. are included. Further, in the present invention, “near” means including a region in a certain range (which can be arbitrarily determined) near a reference position. For example, in the case of the vicinity of A, it is a concept indicating that it is an area in a certain range near A and may or may not include A.

1, 2: Mask manufacturing apparatus 11: Surface plate 11a: Upper surface 11b: Rail 11c: Drive unit 12, 13: Vibration isolation table 20, 20A: First moving units 21, 21a, 21b: Rail 22: Guide rails 23, 23A : Plate-like part 23a: Upper surface 23b: Lower surface 23c: Projection part 23d: Groove 23e, 23f: End face 24, 24A: Projection part 24a: Air discharge part 25: Drive part 25a: Stator 25b: Movable element 25c, 25d: Piping 26: rod-shaped member 27: magnet 28: air discharge unit 29: position measuring unit 29a: scale 29b: detection head 30, 30A: second moving units 31, 31a, 31b: rail 32: guide rail 33, 33A: convex portion 33a : Air discharge unit 34: drive unit 34a: stator 34b: mover 34c, 34d: piping 36: rod-shaped member 37: magnet 38: air discharge unit 39: position Measuring section 39a: scale 39b: detection head 41, 41A: stage 41a: upper surface 41b: lower surface 41c: convex portion 41d: mask lifter hole 41e: air hole 41f: bar mirror 41g: groove 41h, 41i: end surfaces 41i, 41j, 41k : Hole 42: Frame 42a: Pillar 42b: Beams 43, 43a, 43b, 43c, 43d, 43e, 43f, 43g: Light irradiation parts 44a, 44b, 44c: Pins 44d: Pin driving parts 45, 46: Energizing parts 47, 47a, 47b, 47c, 47d, 47e, 47f, 47g: Pattern reading unit 48, 48a, 48b, 48c, 48d, 48e, 48f, 48g: Optical reading unit 51, 52, 53: Laser interferometer 141: On Output device 142: Network 143: Storage medium 151: CPU
151a: Control unit 152: RAM
153: ROM
154: Input / output interface 155: Communication interface 156: Media interface 163: Target coordinate calculator 164: Thrust converter 165: Origin sensor 166, 167, 168: Amplifier 173: Target coordinate calculator 174: Thrust converter 175: Origin sensor 176, 177, 178: Amplifiers 181a, 182a, 183a, 184a, 185a, 186a, 187a, 188a: LUT
181b, 182b, 183b, 184b, 185b, 186b, 187b, 188b, 188c, 188d, 188e, 188f, 188g, 188h: Offset table 191, 192, 193, 194, 195, 196, 197: Position 431: Frame body 432 : Light source 433: Objective lens 434: Connection part 434a: Surface 434b: Surface 434c: Hole 434d: Piezo element 434e: Linear encoder 435: AF (autofocus) processing part 435a: Tube lens group 435b: Beam splitter 435c, 435d: Sensor 436, 437: mirror 439: parallel plate 471: objective lens 472: light source unit 473: lens barrel 474: tube lens 475: mirror 476: UV camera 481: objective lens 482: mirror 483 : Tube 484: Tube lens 485: UV camera

Claims (8)

A plate-like stage on which a mask is placed on a substantially horizontal upper surface, and a stage provided with bar mirrors along two adjacent sides of the upper surface;
A roughly rectangular parallelepiped surface plate,
A first moving part placed on the surface plate, the first moving part having a plate-like part and a first drive part for moving the plate-like part in a first direction;
A second moving part mounted on the upper surface of the plate-like part and having the stage mounted thereon, the second moving part having a second driving part for moving the stage in a second direction; ,
A light irradiating unit for irradiating the mask with light, and a light irradiating unit provided with two mirrors parallel to the bar mirror;
A frame body provided on the surface plate and holding the light irradiation unit above the stage;
A first position measuring unit and a second position measuring unit which are provided on both sides of the first moving unit in the second direction and obtain the position of the plate-like unit in the first direction; and the second moving unit. A position measuring unit provided on both sides in the first direction, and having a third position measuring unit and a fourth position measuring unit for acquiring the position of the stage in the second direction;
A laser interferometer that measures the positional relationship between the light irradiation unit and the stage by measuring the position of the bar mirror with respect to the position of the two mirrors;
The drawing information, which is information about the position and shape of the pattern to be drawn on the mask, is acquired, and the first driving unit and the second driving unit are driven based on the value acquired by the position measuring unit to thereby generate the stage. A control unit that performs a drawing process of irradiating light from the light irradiation unit to the mask based on the drawing information
With
The control unit sets the value acquired by the first position measurement unit and the value acquired by the second position measurement unit to a distance between the first position measurement unit and the second position measurement unit and the light irradiation unit. The weighted average value weighted accordingly, the value acquired by the third position measuring unit and the value acquired by the fourth position measuring unit are used as the third position measuring unit, the fourth position measuring unit, and the light irradiation. Based on the weighted average value weighted according to the distance to the unit, the measured value when the position measuring unit is assumed to be at the position of the light irradiation unit is obtained, and the obtained measured value and the laser interferometer A mask manufacturing apparatus characterized in that the position measurement unit is calibrated by comparing with the measurement results of and the drawing process is performed based on a value acquired by the calibrated position measurement unit. A reading unit provided adjacent to the light irradiation unit or provided in the light irradiation unit,
The controller is
Obtain correction substrate drawing information, which is information about a correction substrate pattern including a plurality of cross positions arranged two-dimensionally,
While controlling the first drive unit and the second drive unit to move the stage in the first direction and the second direction, the light irradiation unit emits light to the mask based on the correction substrate drawing information. Irradiating and drawing the correction substrate pattern on the mask to generate a correction substrate;
The reading unit in each of an initial state when the correction substrate is generated and a state in which the correction substrate is rotated approximately 90 degrees, approximately 180 degrees, and approximately 270 degrees from the initial state. Reading the correction substrate, correcting the drawing information based on the read result,
The mask manufacturing apparatus according to claim 1, wherein the drawing process is performed based on the corrected drawing information.   The control unit matches the result of reading the correction substrate in the initial state with the result of reading the correction substrate in a state in which the correction substrate is rotated by approximately 180 degrees. A correction value is generated so that the result of reading the correction substrate in a state of being rotated by approximately 90 degrees coincides with the result of reading the correction substrate in a state of being rotated by approximately 270 degrees of the correction substrate. The mask manufacturing apparatus according to claim 2, wherein the drawing information is corrected using the generated correction value. The light irradiation unit has an autofocus unit that focuses the light irradiated on the mask on the mask,
The controller is
Controlling the autofocus unit to acquire distance information regarding the distance between the light irradiation unit and the mask, and correcting the drawing information based on the acquired distance information;
The mask manufacturing apparatus according to claim 1, wherein the drawing process is performed based on the corrected drawing information. The light irradiation unit has a surface irradiation unit in which pixels are arranged two-dimensionally,
The drawing information includes positional information that associates the position of the surface irradiation unit with the presence or absence of light irradiation in each pixel of the surface irradiation unit, the position of the surface irradiation unit, and each pixel of the surface irradiation unit. Irradiation timing information in association with the light irradiation timing in
The controller is
The drawing information is corrected by shifting the irradiation timing information for the first direction, and the position information for the second direction.
The drawing process is performed by moving the stage in the first direction to perform drawing for one row, and then moving the stage in the second direction to perform the drawing process. The mask manufacturing apparatus according to item. The light irradiation unit includes an optical member,
The said control part correct | amends the said drawing information by moving the said optical member, The mask manufacturing apparatus as described in any one of Claim 1 to 4 characterized by the above-mentioned. The stage is formed using a material having a thermal expansion coefficient of approximately 1 × 10 ⁻⁷ / K or less,
The mask manufacturing apparatus according to claim 1, wherein the control unit controls the second driving unit so that the stage does not protrude from the plate-like part. A method for controlling a mask manufacturing apparatus in which a mask is placed on an upper surface of a stage, and light is irradiated onto the mask from a light irradiation unit to perform drawing on the mask,
First mounted on both sides in the second direction of the first moving part that is mounted on a substantially rectangular parallelepiped surface plate and has a plate-like part and a first drive part that moves the plate-like part in the first direction. A weighted average value obtained by weighting the values acquired by the first position measurement unit and the second position measurement unit according to the distances between the first position measurement unit, the second position measurement unit, and the light irradiation unit, and the plate shape And a second moving part provided on both sides in the first direction of a second moving part having a second driving part for placing the stage on the top and moving the stage in a second direction. Based on the weighted average value obtained by weighting the values acquired by the three-position measuring unit and the fourth position-measuring unit according to the distance between the third position-measuring unit, the fourth position-measuring unit, and the light irradiation unit. , Obtaining a measurement value at the position of the light irradiation unit;
The position of the light irradiation unit and the stage is determined by measuring the position of the bar mirror provided on the stage with reference to the obtained measurement value and the position of the two mirrors provided on the light irradiation unit. Calibrating the first position measurement unit, the second position measurement unit, the third position measurement unit, and the fourth position measurement unit based on a measurement result of a laser interferometer that measures a relationship;
Based on the values acquired by the first position measuring unit, the second position measuring unit, the third position measuring unit, and the fourth position measuring unit calibrated in the calibrating step, While the second drive unit is driven to move the stage in the horizontal direction, light is emitted from the light irradiation unit to the mask based on drawing information that is information on the position and shape of the pattern drawn on the mask. Drawing on the mask, and
A method for controlling a mask manufacturing apparatus, comprising:

Images