JP2019091076A - Substrate treatment apparatus - Google Patents

Abstract

To correct errors generated on a scale for detecting a position when detecting a position in a circumferential direction of a cylindrical member.SOLUTION: The substrate treatment apparatus comprises: a rotating drum; a treatment part; a first encoder head; a second encoder head; a third encoder head arranged so as to face scale marks in a third direction obtained by rotating by an angle of θs in a circumferential direction to a second direction, the third direction being between a first direction and the second direction about the circumferential direction, and for reading the scale marks; and a storage part for sequentially storing a measured value ΔMs calculated by ΔMs=(Cm1+Cm4)/2-Cm5 at every rotation of a definite angle α of the scale marks, let the first read value by the first encoder be Cm1, the second read value of the second encoder be Cm4, and the third read value of the third encoder be Cm5, to store error information about pitch errors over a whole circumference of the scale marks.SELECTED DRAWING: Figure 25

Description

  The present invention relates to a substrate processing apparatus.

  As an exposure apparatus used in a photolithography process, an exposure apparatus which exposes a substrate using a cylindrical or cylindrical mask as disclosed in the following patent documents is known (for example, Patent Document 1).

  Not only in the case of using a plate-like mask but also in the case of exposing a substrate using a cylindrical or cylindrical mask, Patent Document 1 discloses that the image of the pattern of the mask is well projected onto the substrate. By forming a mark (scale, alignment mark, etc.) for obtaining positional information in a predetermined positional relationship with respect to the pattern in a predetermined area of the pattern formation surface of the cylindrical mask, and detecting the scale with an encoder system, A configuration for acquiring positional information of a pattern in a circumferential direction (or a rotational axis direction) of a pattern formation surface is described.

  In addition, in order to continuously expose a flexible long sheet substrate using a cylindrical mask, the long sheet substrate is wound around a feed roller and supported, and the sheet substrate wound around the feed roller is cylindrically attached. There has also been proposed an exposure apparatus which makes it possible to manufacture a device with high mass productivity (exposure process) by bringing a mask close to each other and rotating a feed roller and a cylindrical mask (see, for example, Patent Document 2).

JP-A-7-153672 JP-A-8-213305

  In a processing apparatus for processing an object to be processed (sheet substrate) on a curved surface of a cylindrical member such as a feed roller as described above, it is required to accurately detect the circumferential position of the cylindrical member. Even when marks (scales) for acquiring position information are engraved on the outer peripheral surface of a cylindrical mask as in Patent Document 1, errors in encoder measurement results due to manufacturing errors of scale marks or expansion or contraction due to temperature, etc. As a result, the detection accuracy of the position of the cylindrical member in the circumferential direction may be reduced.

  The aspect of this invention aims at correcting the error which generate | occur | produced in the graduation for position detection, in detecting the position in the circumferential direction of a cylindrical member.

  According to a first aspect of the present invention, there is provided a substrate processing apparatus for transporting a flexible long sheet substrate in a longitudinal direction and performing predetermined processing on the sheet substrate, wherein the processing is performed at a constant distance from the center line. A rotary drum for supporting the sheet substrate by a cylindrically curved outer peripheral surface with a radius and for conveying the sheet substrate in the longitudinal direction by rotating around the center line, and the outer periphery of the rotary drum for the sheet substrate A processing unit for processing the sheet substrate at a specific position within a circumferential range supported by a surface, and a ring provided along the circumferential direction in which the rotating drum rotates, and the centerline with the rotating drum A scale scale for encoder measurement of a positional change in the circumferential direction of the sheet substrate, and the first scale in the circumferential direction are arranged to face the scale scale, and the scale scale is read. 1 encoder head, a second encoder head arranged to face the scale graduation in a second orientation rotated by an angle θ q in the circumferential direction with respect to the first orientation, and reading the scale graduation in the circumferential direction Are arranged between the first orientation and the second orientation, and face the scale in a third orientation rotated by an angle .theta.s in the circumferential direction with respect to the second orientation. A third encoder head for reading the scale mark, a first reading value by the first encoder head is Cm1, a second reading value by the second encoder head is Cm4, and a third reading value by the third encoder head is Cm5. And the measured value .DELTA.Ms calculated by .DELTA.Ms = (Cm1 + Cm4) / 2-Cm5 is successively removed for each rotation of the fixed angle .alpha. Stored, a storage unit for storing the error information about the pitch error over the entire circumference of the scale graduation, a substrate processing apparatus including a is provided.

  According to the aspect of the present invention, when detecting the position in the circumferential direction of the cylindrical member, it is possible to correct the error generated in the scale for position detection.

FIG. 1 is a schematic view showing the overall configuration of a substrate processing apparatus (exposure apparatus) according to the embodiment. FIG. 2 is a schematic view showing the arrangement of the illumination area and the projection area in FIG. FIG. 3 is a schematic view showing a configuration of a projection optical system applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 4 is a perspective view of a second drum member (rotary drum) applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 5 is a perspective view for explaining the relationship between a detection probe and a reader applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 6 is an explanatory view in which the positions of the encoder scale disk and the reading device according to the embodiment are viewed in a plane orthogonal to the rotation center line. FIG. 7 is an enlarged view schematically showing the scale scale. FIG. 8 is a schematic view showing the positional relationship between the scale and the encoder head. FIG. 9 is a flowchart showing a procedure for correcting scale pitch error. FIG. 10 is a diagram showing the relationship between a scale disk having a scale on the outer peripheral surface and an encoder head. FIG. 11 is a diagram showing an example of the correction map. FIG. 12 is a conceptual diagram showing the timing when obtaining these readings from a pair of encoder heads. FIG. 13 is a conceptual diagram showing timings when obtaining these read values from a pair of encoder heads. FIG. 14 is a flow chart showing the procedure for correcting the scale error. FIG. 15 is an explanatory view for explaining a roundness adjusting mechanism for adjusting the roundness of the encoder scale disc. FIG. 16 is an explanatory view for explaining a roundness adjusting mechanism for adjusting the roundness of the encoder scale disc. FIG. 17 is a schematic view showing a first modified example of the substrate processing apparatus (exposure apparatus). FIG. 18 is an explanatory view for explaining the position of the reading device when the encoder scale disk according to the first modification of the substrate processing apparatus (exposure apparatus) is viewed in the direction of the rotation center line. FIG. 19 is a schematic view showing an entire configuration of a second modified example of the substrate processing apparatus (exposure apparatus). FIG. 20 is a schematic view showing an entire configuration of a third modified example of the substrate processing apparatus (exposure apparatus). FIG. 21 is a schematic view showing an entire configuration of a fourth modified example of the substrate processing apparatus (exposure apparatus). FIG. 22 is a signal waveform diagram for briefly describing the actual reading operation of the scale by the encoder head shown in each of FIGS. 4 to 6 and FIG. 10 and FIGS. FIG. 23 is a view of the configuration in the case of forming a scale on the side end face of the scale disk, as seen in the direction in which the rotation center line extends, as in FIG. FIG. 24 is a cross-sectional view taken along the line A-A 'in which the configuration of FIG. FIG. 25 is a view of the arrangement of the scale disc and the encoder head in the XZ plane, as in FIG. FIG. 26 is a flowchart showing the procedure of a device manufacturing method for manufacturing a device using the substrate processing apparatus (exposure apparatus) according to the embodiment.

  A mode (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiments described below. In the following embodiments, various processing for manufacturing one type of device will be described as an exposure apparatus used in a so-called roll-to-roll method in which a substrate is continuously subjected. Further, in the following, an XYZ orthogonal coordinate system is set, and the positional relationship of each part will be described with reference to this XYZ orthogonal coordinate system. As an example, a predetermined direction in the horizontal plane is the X axis direction, a direction orthogonal to the X axis direction in the horizontal plane is the Y axis direction, a direction orthogonal to each of the X axis direction and the Y axis direction (ie vertical direction) the Z axis direction I assume.

  FIG. 1 is a schematic view showing the overall configuration of a substrate processing apparatus (exposure apparatus) according to the embodiment. FIG. 2 is a schematic view showing the arrangement of the illumination area and the projection area in FIG. FIG. 3 is a schematic view showing a configuration of a projection optical system applied to the substrate processing apparatus (exposure apparatus) of FIG. As shown in FIG. 1, the substrate processing apparatus 11 includes an exposure apparatus (processing unit) EX and a sheet substrate conveyance apparatus (hereinafter, appropriately referred to as a conveyance apparatus) 9. The exposure apparatus EX is supplied with a substrate P (sheet, film or the like) by the transport device 9. For example, the substrate P of a long sheet of flexible sheet drawn out from a supply roll (not shown) is sequentially processed by the substrate processing apparatus (exposure apparatus) 11 through the substrate processing apparatus for the preprocess. There is a device manufacturing system which is wound up on a recovery roll after being delivered to the substrate processing apparatus for the post process by the transport apparatus 9. Thus, the substrate processing apparatus 11 can be used as part of a device manufacturing system (a manufacturing line of flexible displays).

  The exposure apparatus EX as the substrate processing apparatus 11 is a so-called scanning exposure apparatus, and a pattern formed on the cylindrical mask DM while synchronously driving the rotation of the cylindrical mask DM and the feeding of the flexible substrate P. Is projected onto the substrate P via a projection optical system PL (PL1 to PL6) having a projection magnification of 1 × (× 1). The exposure apparatus EX shown in FIG. 1 sets the Y axis of the XYZ orthogonal coordinate system in parallel with the rotation center line AX1 of the first drum member 21 constituting the cylindrical mask DM. Similarly, the rotation center line AX2 of the second drum member 22 as a cylindrical member for instructing a part of the substrate P in the longitudinal direction in a cylindrical shape is set parallel to the Y axis of the XYZ orthogonal coordinate system.

  As shown in FIG. 1, the exposure apparatus EX includes a mask holding device 12, an illumination mechanism IU, a projection optical system PL, and a control device 14. The exposure apparatus EX rotationally moves (pivots) the cylindrical mask DM held by the mask holding device 12 and conveys the substrate P by the conveying device 9. A part (illumination region IR) of the cylindrical mask DM held by the mask holding device 12 together with the illumination mechanism IU is illuminated by the illumination light beam EL1 with uniform brightness. The projection optical system PL projects an image of a pattern in the illumination area IR on the cylindrical mask DM onto a portion (projection area PA) of the substrate P being transported by the transport device 9. As the cylindrical mask DM moves, the portion on the cylindrical mask DM arranged in the illumination region IR changes. Further, with the movement of the substrate P, the portion on the substrate P arranged in the projection area PA changes. By doing this, an image of a predetermined pattern (mask pattern) formed on the surface of the cylindrical mask DM is projected onto the cylindrical surface of the substrate P via the projection optical system PL (PL1 to PL6). . The control device 14 controls each part of the exposure apparatus EX to cause each part to execute processing. Further, in the present embodiment, the control device 14 controls the transport device 9.

  The control device 14 may be part or all of a higher-level control device that centrally controls the plurality of substrate processing devices of the device manufacturing system described above. Further, the control device 14 may be controlled by the host control device, and may be a device different from the host control device. The controller 14 includes, for example, a computer system. The computer system includes, for example, hardware such as a central processing unit (CPU), various memories, an operating system (OS), and peripheral devices. The operation sequence and parameters of each part of the substrate processing apparatus 11 are stored in a computer readable recording medium in the form of a computer program, and the computer system reads and executes this program to perform various processes.

  The computer system also includes a home page providing environment (or display environment) when it can connect to the Internet or an intranet system. Further, the computer readable recording medium includes a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM and the like, and a storage device such as a hard disk built in a computer system. A computer-readable recording medium holds a computer program dynamically for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, It also includes programs that hold programs for a certain period of time, such as volatile memory in the computer system that becomes the server or client of the case. The computer program may be for realizing a part of the functions of the substrate processing apparatus 11, or may be one which can realize the functions of the substrate processing apparatus 11 in combination with a program already recorded in the computer system. The host control device can be realized using a computer system, similarly to the control device 14.

  As shown in FIG. 1, the mask holding device 12 includes a first drum member 21 for holding the cylindrical mask DM, a guide roller 23 for supporting the first drum member 21, and a first drive unit 26 according to control commands of the control device 14 A drive roller 24 for driving the first drum member 21 and a first detector 25 for detecting the position of the first drum member 21 are provided.

  The first drum member 21 is a cylindrical member having a curved surface which is curved at a constant radius from a rotation center line AX1 (hereinafter, appropriately referred to as a first center axis AX1 as well) having a predetermined axis, and around the rotation center line AX1. Rotate. The first drum member 21 has a first surface P1 on which the illumination region IR of the cylindrical mask DM is disposed, and the first surface P1 has a line segment (genome) as a first central axis parallel to the line segment It is a cylindrical surface formed by rotating around AX1. The cylindrical surface is, for example, an outer peripheral surface of a cylinder, an outer peripheral surface of a cylinder, or the like. The first drum member 21 is made of, for example, glass or quartz and has a cylindrical shape with a certain thickness, and the outer peripheral surface (cylindrical surface) is the first surface P1. That is, in the present embodiment, the illumination region IR of the cylindrical mask DM is curved in a cylindrical surface shape having a constant radius r1 from the rotation center line AX1. As described above, the first drum member 21 has a curved surface (cylindrical surface with a predetermined curvature) curved at a constant radius from the rotation center line AX1.

  The cylindrical mask DM is formed, for example, as a transmission-type flat sheet mask in which a pattern is formed by a light shielding layer such as chromium on one surface of a strip-like ultrathin glass plate (for example, 100 μm to 500 μm thick) having high flatness. Be done. The mask holding device 12 is used in a state in which a cylindrical mask DM made of an ultrathin glass plate is curved according to the curved surface of the outer peripheral surface of the first drum member 21 and wound (pasted) on this curved surface. The cylindrical mask DM has a non-patterned area where no pattern is formed, and the non-patterned area is attached to the first drum member 21. The cylindrical mask DM is attachable to and detachable from the first drum member 21.

  Instead of winding the cylindrical mask DM on the first drum member 21 of a transparent cylindrical base material, the first drum member 21 is manufactured of a transparent cylindrical base material such as quartz instead of forming the cylindrical mask DM with an extremely thin glass plate. Alternatively, a mask pattern of a light shielding layer such as chromium may be drawn and formed directly on the outer peripheral surface thereof. Also in this case, the first drum member 21 functions as a support member for the pattern of the cylindrical mask DM.

  The first detector 25 optically detects the rotational position of the first drum member 21 and is constituted of, for example, a rotary encoder or the like. The encoder may be absolute or incremental. The first detector 25 outputs information indicating the detected rotational position of the first drum member 21, for example, a two-phase signal from an encoder head described later, to the control device 14. The first drive unit 26 including an actuator such as an electric motor adjusts torque and rotation speed for rotating the drive roller 24 according to a control signal input from the control device 14. The control device 14 controls the rotational position of the first drum member 21 by controlling the first drive unit 26 based on the detection result of the first detector 25. Then, the control device 14 controls one or both of the rotational position and the rotational speed of the cylindrical mask DM held by the first drum member 21.

  The transport device 9 includes a drive roller DR4, a first guide member 31, and a second drum member 22 forming a second surface P2 on which the projection area PA of the substrate P is disposed, a second guide member 33, drive rollers DR4, DR5, A second detector 35 and a second drive unit 36 are provided.

  In the present embodiment, the substrate P transported to the drive roller DR4 from the upstream side of the transport path of the substrate P, that is, the side opposite to the transport (movement) direction of the substrate P is a first guide via the drive roller DR4. It is conveyed to the member 31. The substrate P having passed through the first guide member 31 is supported by the surface of a cylindrical or cylindrical second drum member 22 with a radius r 2, and is conveyed to the second guide member 33. The substrate P having passed through the second guide member 33 is transported to the downstream of the transport path. The rotation center line AX2 of the second drum member 22 and the rotation center lines of the drive rollers DR4 and DR5 are both set parallel to the Y axis.

  The first guide member 31 and the second guide member 33 adjust the tension or the like in the transport direction acting on the substrate P in the transport path by moving in the transport direction of the substrate P, for example. The first guide member 31 (and the drive roller DR4) and the second guide member 33 (and the drive roller DR5) are, for example, the width direction of the substrate P (the direction orthogonal to the transport direction of the substrate P). By setting the position of the substrate P wound around the outer periphery of the second drum member 22 in the Y direction, etc. can be adjusted. In addition, the conveyance apparatus 9 should just be able to convey the board | substrate P along the projection area | region PA of the projection optical system PL, and the structure of the conveyance apparatus 9 can be changed suitably.

  The second drum member 22 is a cylindrical member having a curved surface (cylindrical surface with a predetermined curvature) curved at a constant radius from a rotation center line AX2 (hereinafter, also referred to as a second center axis AX2 as appropriate) serving as a predetermined axis. , And a rotary drum that rotates around a second central axis AX2. The second drum member 22 forms a second surface (supporting surface) P2. The second surface P2 is a portion of the substrate P onto which the imaging light beam from the projection optical system PL is projected, and supports a portion including the projection area PA in an arc shape (cylindrical shape). In the present embodiment, the second drum member 22 is a part of the transfer device 9 and also serves as a support member (substrate stage) for supporting the substrate P to be exposed. That is, the second drum member 22 may be a part of the exposure apparatus EX. Thus, the second drum member 22 is rotatable around its rotation center line AX2 (second center axis AX2), and the substrate P follows the outer peripheral surface (cylindrical surface) on the second drum member 22. The projection area PA is disposed on a part of the substrate P which is curved in a cylindrical surface shape and curved. For this reason, the substrate P is pivotally moved on the circumferential surface portion including the projection area PA in the cylindrical surface of the radius r2.

  In the present embodiment, the second drum member 22 is rotated by the torque supplied from the second drive unit 36 including an actuator such as an electric motor. The second detector 35 is formed of, for example, a rotary encoder, and optically detects the rotational position of the second drum member 22. The second detector 35 outputs information indicating the detected rotational position of the second drum member 22 (for example, two-phase signals from encoder heads EN1, EN2, EN3, EN4, and EN5 described later) to the control device 14 . The second drive unit 36 adjusts the torque and the rotational speed for rotating the second drum member 22 in accordance with the control signal supplied from the control device 14. The control device 14 controls the rotational position of the second drum member 22 by controlling the second drive unit 36 based on the detection result of the second detector 35, and the first drum member 21 (cylindrical mask DM) and the like. The second drum member 22 is synchronously moved (synchronously rotated). The details of the second detector 35 will be described later.

  The exposure apparatus EX is an exposure apparatus on which it is assumed that a so-called multi-lens type projection optical system PL is mounted. The projection optical system PL includes a plurality of projection modules that project an image of a portion of the pattern of the cylindrical mask DM. For example, in FIG. 1, with respect to a center plane P3 parallel to the YZ plane, including the rotation center line AX1 of the cylindrical mask DM and the second center axis AX2 of the second drum member 22, Three projection modules (projection optical systems) PL1, PL3 and PL5 are arranged at regular intervals in the Y direction on the opposite side), and three projection modules (projections on the transport direction side of the substrate P) on the right side of the central plane P3. Optical systems) PL2, PL4, and PL6 are arranged at regular intervals in the Y direction.

  In such a multi-lens exposure apparatus EX, the end portions in the Y direction of the areas (projection areas PA1 to PA6) exposed by the plurality of projection modules PL1 to PL6 are overlapped with each other by scanning to obtain a desired pattern. Project the whole picture. In such an exposure apparatus EX, even if the dimension in the Y direction of the pattern on the cylindrical mask DM becomes large and the necessity of handling the substrate P having a large width in the Y direction inevitably arises, the projection module PL and the projection Since it is only necessary to add the module on the illumination mechanism IU side corresponding to the module PL in the Y direction, there is an advantage of being able to easily cope with the enlargement of the display panel size (width of the substrate P).

  The exposure apparatus EX may not be a multi-lens system. For example, when the dimension in the width direction of the substrate P is somewhat small, the exposure apparatus EX may project an image of the entire width of the pattern onto the substrate P by one projection module. In addition, each of the plurality of projection modules PL1 to PL6 may project a pattern corresponding to one device. That is, the exposure apparatus EX may project patterns for a plurality of devices in parallel by a plurality of projection modules.

  The illumination mechanism IU includes the light source device 13 and an illumination optical system. The illumination optical system includes a plurality (for example, six) of illumination modules IL aligned in the Y-axis direction corresponding to each of the plurality of projection modules PL1 to PL6. The light source device 13 includes, for example, a lamp light source such as a mercury lamp, a solid state light source such as a laser diode or a light emitting diode (LED), or a gas laser light source. The illumination light emitted from the light source device is, for example, a bright line (g line, h line, i line) emitted from a lamp light source, far ultraviolet light (DUV light) such as KrF excimer laser light (wavelength 248 nm), ArF excimer laser light (Wavelength 193 nm) or the like. The illumination light emitted from the light source device 13 has a uniform illuminance distribution, and is distributed to the plurality of illumination modules IL via a light guide member such as an optical fiber, for example.

  Each of the plurality of illumination modules IL includes a plurality of optical members such as a lens. In the present embodiment, light emitted from the light source device 13 and passing through any of the plurality of illumination modules IL is referred to as an illumination light flux EL1. Each of the plurality of illumination modules IL includes, for example, an integrator optical system, a rod lens, a fly's eye lens, and the like, and illuminates the illumination region IR with the illumination light beam EL1 of uniform illuminance distribution. In the present embodiment, the plurality of illumination modules IL are disposed inside the cylindrical mask DM. Each of the plurality of illumination modules IL illuminates each illumination area IR of the mask pattern formed on the outer peripheral surface of the cylindrical mask DM from the inside of the cylindrical mask DM.

  FIG. 2 is a diagram showing the arrangement of the illumination area IR and the projection area PA in the present embodiment. In FIG. 2, a plan view of the illumination area IR on the cylindrical mask DM disposed on the first drum member 21 as viewed from the −Z side (the left side in FIG. 2) and the second drum member 22 The top view (figure on the right side in FIG. 2) which looked at projection area PA on the board | substrate P arrange | positioned from the + Z side is shown in figure. The code | symbol Xs in FIG. 2 shows the rotation direction (movement direction) of the 1st drum member 21 (cylindrical mask DM) or the 2nd drum member 22. As shown in FIG.

  The plurality of illumination modules IL respectively illuminate the first to sixth illumination areas IR1 to IR6 on the cylindrical mask DM. For example, the first illumination module IL illuminates the first illumination area IR1, and the second illumination module IL illuminates the second illumination area IR2.

  Although the first illumination area IR1 is described as a trapezoidal area elongated in the Y direction, in the case of a projection optical system that forms an intermediate image plane like the projection optical system (projection module) PL, the position of the intermediate image And a field stop plate having a trapezoidal opening. Therefore, the first illumination area IR1 may be a rectangular area including the trapezoidal opening. The third illumination region IR3 and the fifth illumination region IR5 are regions of the same shape as the first illumination region IR1, respectively, and are arranged at constant intervals in the Y-axis direction. Further, the second illumination area IR2 is a trapezoidal (or rectangular) area symmetrical to the first illumination area IR1 with respect to the central plane P3. The fourth illumination region IR4 and the sixth illumination region IR6 are regions of the same shape as the second illumination region IR2, respectively, and are arranged at constant intervals in the Y-axis direction.

  As shown in FIG. 2, when viewed along the circumferential direction of the first surface P1, each of the first to sixth illumination regions IR1 to IR6 is an oblique side portion of a trapezoidal illumination region adjacent in the Y-axis direction Are arranged so that their triangles overlap. Therefore, for example, the first area A1 on the cylindrical mask DM passing the first illumination area IR1 by the rotation of the first drum member 21 passes the second illumination area IR2 by the rotation of the first drum member 21. It partially overlaps with the upper second area A2.

  In the present embodiment, the cylindrical mask DM includes a pattern formation area A3 in which a pattern is formed and a pattern non-formation area A4 in which a pattern is not formed. The non-pattern formation area A4 is disposed to surround the pattern formation area A3 in a frame shape, and has a characteristic of shielding the illumination light beam EL1. The pattern formation area A3 of the cylindrical mask DM moves in the moving direction Xs along with the rotation of the first drum member 21, and the partial areas in the Y axis direction of the pattern formation area A3 are the first to sixth illumination areas Pass one of IR1 to IR6. That is, the first to sixth illumination areas IR1 to IR6 are arranged to cover the full width of the pattern formation area A3 in the Y-axis direction.

  As shown in FIG. 1, each of the plurality of projection modules PL1 to PL6 aligned in the Y-axis direction corresponds to each of the first to sixth illumination modules IL on a one-to-one basis, and illumination is performed by the corresponding illumination modules IL. An image of a partial pattern of the cylindrical mask DM appearing in the illumination area IR to be projected is projected onto each projection area PA on the substrate P. For example, the first projection module PL1 corresponds to the first illumination module IL, and the image of the pattern of the cylindrical mask DM in the first illumination area IR1 (see FIG. 2) illuminated by the first illumination module IL is displayed on the substrate P On the first projection area PA1 of the The third projection module PL3 and the fifth projection module PL5 correspond to the third to fifth illumination modules IL, respectively. The third projection module PL3 and the fifth projection module PL5 are disposed at positions overlapping with the first projection module PL1 when viewed from the Y-axis direction.

  Further, the second projection module PL2 corresponds to the second illumination module IL, and the image of the pattern of the cylindrical mask DM in the second illumination area IR2 (see FIG. 2) illuminated by the second illumination module IL is displayed on the substrate P. To the second projection area PA2 of When viewed in the Y-axis direction, the second projection module PL2 is disposed at a symmetrical position with respect to the first projection module PL1 across the central plane P3.

  The fourth projection module PL4 and the sixth projection module PL6 are respectively disposed in correspondence with the fourth and sixth illumination modules IL, and the fourth projection module PL4 and the sixth projection module PL6 are viewed from the Y-axis direction, It is arrange | positioned in the position which overlaps with 2nd projection module PL2. With such an arrangement, the odd-numbered first projection area PA1, the third projection area PA3, and the fifth projection area PA5 are arranged in a line in the Y-axis direction with a certain amount of deviation from the central plane P3 in the -X direction. Be done. The even-numbered second projection area PA2, the fourth projection area PA4, and the sixth projection area PA6 are arranged in a line in the Y-axis direction at a predetermined distance from the center plane P3 in the + X direction.

  In the present embodiment, the light reaching each of the illumination areas IR1 to IR6 on the cylindrical mask DM from the illumination modules IL of the illumination mechanism IU is referred to as an illumination luminous flux EL1. In addition, the light beams subjected to intensity distribution modulation according to the pattern of the cylindrical mask DM appearing in the respective illumination areas IR1 to IR6 and incident on the respective projection modules PL1 to PL6 to reach the respective projection areas PA1 to PA6 I assume. Then, among the imaging light beams EL2 reaching the projection areas PA1 to PA6, the chief ray passing through the center points of the projection areas PA1 to PA6 is the second central axis AX2 of the second drum member 22, as shown in FIG. From the center plane P3 in the circumferential direction (specific position).

  In each of the first to sixth projection areas PA1 to PA6, end portions (trapezoidal triangle portions) of projection areas (odd-numbered and even-numbered) adjacent in the direction parallel to the second central axis AX2 They are arranged to overlap in the circumferential direction of P2. Therefore, for example, the third area A5 on the substrate P passing the first projection area PA1 by the rotation of the second drum member 22 is on the substrate P passing the second projection area PA2 by the rotation of the second drum member 22. It partially overlaps with the fourth area A6. The first projection area PA1 and the second projection area PA2 are arranged such that the exposure amount in the area where the third area A5 and the fourth area A6 overlap is substantially the same as the exposure amount in the non-overlapping area. The shape etc. are set.

  Next, the detailed configuration of the projection optical system PL of the present embodiment will be described with reference to FIG. In the present embodiment, each of the second to fifth projection modules PL2 to PL5 has the same configuration as that of the first projection module PL1. Therefore, as a representative of the projection optical system PL, the configuration of the first projection module PL1 will be described, and the description of each of the second to fifth projection modules PL2 to PL5 will be omitted.

  In the first projection module PL1 shown in FIG. 3, the first optical system 41 for forming an image of the pattern of the cylindrical mask DM disposed in the first illumination region IR1 on the intermediate image plane P7 and the first optical system 41 are formed. A second optical system 42 for re-forming at least a part of the intermediate image on the first projection area PA1 of the substrate P, and a first field stop 43 disposed on an intermediate image plane P7 on which the intermediate image is formed .

  The first projection module PL1 further includes a focus correction optical member 44, an image shift correction optical member 45, a rotation correction mechanism 46, and a magnification correction optical member 47. The focus correction optical member 44 is a focus adjustment device that finely adjusts the focus state of a pattern image (hereinafter referred to as a projection image) of a mask formed on the substrate P. Further, the image shift correction optical member 45 is a shift adjustment device which slightly shifts the projected image laterally in the image plane. The magnification correction optical member 47 is a shift adjustment device that slightly corrects the magnification of the projected image. The rotation correction mechanism 46 is a shift adjustment device that slightly rotates the projected image in the image plane.

  The imaging light beam EL2 from the pattern of the cylindrical mask DM is emitted from the first illumination region IR1 in the normal direction (D1), passes through the focus correction optical member 44, and is incident on the image shift correction optical member 45. The imaging light beam EL 2 transmitted through the image shift correction optical member 45 is reflected by the first reflection surface (plane mirror) p 4 of the first deflection member 50 which is an element of the first optical system 41, and passes through the first lens group 51. The light is reflected by the first concave mirror 52 disposed at the pupil position, is reflected again by the second reflection surface (plane mirror) p5 of the first deflection member 50 through the first lens group 51, and is incident on the first field stop 43 . The imaging light beam EL2 having passed through the first field stop 43 is reflected by the third reflection surface (plane mirror) p8 of the second deflection member 57 which is an element of the second optical system 42, and passes through the second lens group 58 It is reflected by the second concave mirror 59 disposed at the position, is reflected again by the fourth reflecting surface (planar mirror) p9 of the second deflection member 57 through the second lens group 58, and enters the magnification correction optical member 47. . The image forming light beam EL2 emitted from the magnification correction optical member 47 is incident on the first projection area PA1 on the substrate P, and the image of the pattern appearing in the first illumination area IR1 is equal-magnified in the first projection area PA1 (× Projected in 1).

  Assuming that the radius of the cylindrical mask DM shown in FIG. 1 is r1 and the radius of the cylindrical surface of the substrate P wound around the second drum member 22 is r2, the radius r1 and the radius r2 are equal, each projection module PL1 to PL1 The chief ray of the imaging light beam EL2 on the mask side of PL6 is inclined to pass through the central axis AX1 of the cylindrical mask DM. The inclination angle is the same as the inclination angle θ (± θ with respect to the center plane P3) of the principal ray of the imaging light beam EL2 on the substrate P side.

  In order to give the inclination angle θ described above, the angle θ1 of the first reflecting surface p4 of the first deflection member 50 with respect to the optical axis AX3 shown in FIG. 3 is smaller than 45 ° by Δθ1 and the second deflection with respect to the optical axis AX4 The angle θ4 of the fourth reflection surface p9 of the member 57 is smaller than 45 ° by Δθ4. Δθ1 and Δθ4 are set to the relationship of Δθ1 = Δθ4 = θ / 2 with respect to the angle θ shown in FIG.

  FIG. 4 is a perspective view of a second drum member 22 (rotary drum) applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 5 is a perspective view for explaining the relationship between a detection probe and a reader applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 6 is an explanatory view of the positions of the encoder scale disk and the reader according to the embodiment as viewed in the XZ plane orthogonal to the rotation center line AX2. In FIG. 4, for convenience, only the second to fourth projection areas PA2 to PA4 are illustrated, and the first, fifth, and sixth projection areas PA1, PA5, and PA6 are not illustrated.

  The second detector 35 shown in FIG. 1 optically detects the position of the second drum member 22 (more specifically, the rotational position), and as a scale member as shown in FIG. 4 to FIG. And an encoder scale disk (disk) SD of high circularity, and encoder heads EN1, EN2, EN3, EN4, EN5 as reading units.

  The encoder scale disc SD is fixed to one end of the second drum member 22 orthogonal to the rotation axis ST of the second drum member 22. For this reason, the encoder scale disk SD rotates integrally with the rotation axis ST around the rotation center line AX2. The encoder scale disc SD may be fixed to both ends of the second drum member 22. That is, the encoder scale disc SD may be fixed to at least one end of the second drum member 22.

  On the outer peripheral surface of the encoder scale disc SD, a plurality of scale (division lines) GP as a scale for position detection for detecting the position or the amount of change in position of the second drum member 22 (cylindrical member) in the circumferential direction It is done. Hereinafter, the scale GP is appropriately referred to as a scale GP. The portion of the encoder scale disc SD where the scale GP is engraved is a scale portion. In the plurality of graduations GP, grid lines with a pitch of, for example, 20 μm are annularly arranged along the direction in which the second drum member 22 rotates, and with the second drum member 22 around the rotation axis ST (second central axis AX2) Rotate.

  The encoder heads EN1, EN2, EN3, EN4, and EN5 are disposed around the graduation GP as opposed to the graduation GP with a constant gap as viewed from the rotation axis ST (the second rotation center line AX2). Each encoder head EN1 to EN5 is a non-contact type sensor that projects a measurement beam on a scale GP and photoelectrically detects a beam (diffracted light) reflected by the scale GP. The encoder heads EN1 to EN5 are arranged in different azimuths (angular positions) in the circumferential direction of the scale disc SD when viewed from the rotation axis ST (second rotation center line AX2) of the second drum member 22. There is.

  Each of the encoder heads EN1 to EN5 is a reading device having measurement sensitivity (detection sensitivity) with respect to variation in displacement in the tangential direction (in the XZ plane) of the scale GP. As shown in FIG. 4, when the installation azimuths (angular directions in the XZ plane around the rotation center line AX2) of the encoder heads EN1 to EN5 are represented by installation azimuth lines Le1, Le2, Le3, Le4, and Le5, As shown in FIG. 6, the encoder heads EN1 and EN2 are arranged such that the installation azimuth lines Le1 and Le2 are at an angle ± θ ° with respect to the central plane P3. In the present embodiment, the angle θ is 15 ° as an example, but is not limited to this.

  The projection modules PL1 to PL6 illustrated in FIG. 3 are also processing units that use the substrate P as an object to be processed, and irradiate the substrate P with a light beam as a pattern image to perform an exposure process. From this, the exposure apparatus EX includes a first processing unit including odd-numbered projection modules PL1, PL3, and PL5, and a second processing unit including even-numbered projection modules PL2, PL4, and PL6. In contrast, when the chief ray of the imaging light beam EL2 from each of the first processing unit and the second processing unit (for example, the chief ray passing through the central point of the projection area PA) is viewed in the XZ plane, It is incident vertically. As such, the position where the chief ray is incident on the substrate P is taken as the specific position where the substrate P is to be treated (here, the irradiation of the imaging light flux).

  The specific position is set at a position of an angle ± θ in the circumferential direction from the center plane P3 on the substrate P supported on the outer peripheral surface of the second drum member 22 when viewed from the second central axis AX2 of the second drum member 22 ing. As shown in FIGS. 4 and 6, the installation azimuth line Le1 of the encoder head EN1 is a chief ray passing through the center points of the projection areas (projection fields) PA1, PA3 and PA5 of the odd-numbered projection modules PL1, PL3 and PL5. Is arranged so as to coincide with the inclination angle θ with respect to the central plane P3. Similarly, the installation azimuth line Le2 of the encoder head EN2 is an inclination angle of the chief ray passing through the central points of the projection areas (projection fields) PA2, PA4 and PA6 of the even-numbered projection modules PL2, PL4 and PL6 with respect to the central plane P3. It is arranged to coincide with θ. For this reason, the encoder heads EN1 and EN2 read the graduations on the graduation GP located in the direction connecting each specific position and the second central axis AX2.

  The encoder head EN4 is disposed upstream of the encoder head EN1 in the transport direction of the substrate P, that is, in front of the exposure position (projection area). And encoder head EN4 is arrange | positioned on installation azimuth line Le4. The installation azimuth line Le4 is at a position where the installation azimuth line Le1 of the encoder head EN1 is rotated approximately 90 ° around the axis of the rotation center line AX2 toward the upstream side of the transport direction of the substrate P. Also, the encoder head EN5 is disposed on the installation azimuth line Le5. The installation azimuth line Le5 is at a position where the installation azimuth line Le2 of the encoder head EN2 is rotated approximately 90 ° around the axis of the rotation center line AX2 toward the upstream side in the transport direction of the substrate P.

  As exemplified above, the principal ray of the imaging light flux EL2 passing through the centers of the odd-numbered projection areas PA1, PA3 and PA5, and the main light of the imaging light flux EL2 passing through the centers of the even-numbered projection areas PA2, PA4 and PA6. When the inclination angle ± θ with respect to the central plane P3 with the light beam is 15 °, the opening angle in the XZ plane of the installation azimuth line Le1 and the installation azimuth line Le2 is 30 °. Therefore, the opening angle in the XZ plane of the installation azimuth line Le4 and the installation azimuth line Le5 is also approximately 30 °.

  When the directions of the installation azimuth lines Le4 and Le5 where the encoder heads EN4 and EN5 for reading the graduation GP are disposed by arranging the encoder heads EN4 and EN5 as viewed from the rotation center line AX2 in the XZ plane The direction in which the chief ray of the imaging light beam EL2 enters the specific position of the substrate P with respect to the substrate P is substantially orthogonal to the direction. Therefore, even if the second drum member 22 is shifted in the Z direction by a slight rattle (about 2 μm to 3 μm) of a bearing that supports the rotation shaft ST, this shift occurs in the projection areas PA1 to PA6 due to this shift. Position errors in a direction along the imaging light beam EL2 to be obtained can be measured with high accuracy by the encoder heads EN1 and EN2.

  Also, the encoder head EN3 is disposed on the installation azimuth line Le3. In the installation azimuth line Le3, the installation azimuth line Le2 of the encoder head EN2 rotates approximately 120 ° around the axis of the rotation center line AX2, and the installation azimuth line Le4 of the encoder head EN4 rotates around the axis of the rotation center line AX2. It is set to a position rotated approximately 120 ° in the direction opposite to the direction of rotation of the line Le2. That is, when viewed in the XZ plane, the three installation azimuth lines Le2, Le3 and Le4 extending from the rotation center line AX2 are set at an interval of approximately 120 °.

  The encoder scale disc SD, which is a scale member, uses, for example, a metal having a low coefficient of thermal expansion, glass, or a ceramic as a base material. The encoder scale disc SD is made as large as possible (for example, 20 cm or more in diameter) in order to increase the resolution of measurement. In FIG. 4, the diameter of the encoder scale disc SD is illustrated to be smaller than the diameter of the second drum member 22, but of the outer peripheral surface of the second drum member 22, the diameter of the outer peripheral surface on which the substrate P is wound; The measurement Abbe error can be further reduced by making the diameters of the graduations GP of the encoder scale disc SD uniform (approximately the same).

  The minimum pitch of the graduations GP engraved in the circumferential direction of the encoder scale disc SD is limited by the performance of a graduation line device or the like for processing the encoder scale disc SD. Therefore, if the diameter of the encoder scale disk SD is increased, the angle measurement resolution corresponding to the minimum pitch can be increased accordingly. The principal ray of the imaging light beam EL2 enters the substrate P with respect to the substrate P when the directions of the installation azimuth lines Le1 and Le2 in which the encoder heads EN1 and EN2 reading the graduation GP are arranged are viewed from the rotation center line AX2. For example, even if the second drum member 22 is shifted in the X direction by a slight backlash (about 2 .mu.m to 3 .mu.m) of a bearing that supports the rotation shaft ST, projection is performed by this shift. It is possible to measure with high accuracy the encoder head EN1 or EN2 for a positional error in the feed direction (Xs) of the substrate P that may occur in the areas PA1 to PA6.

  As shown in FIG. 5, the image of the portion of the mask pattern projected by the projection optical system PL shown in FIG. 1 is relative to the substrate P on the portion of the substrate P supported by the curved surface of the second drum member 22. In order to align (alignment), a plurality of alignment microscopes AMG1 and AMG2 for detecting alignment marks and the like formed in advance on the substrate P are provided. The alignment microscopes AMG1 and AMG2 are pattern detection devices disposed around the second drum member 22. The alignment microscopes AMG1 and AMG2 are detection probes for detecting a specific pattern formed discretely or continuously on the substrate P. The detection area by the detection probe is disposed upstream of the above-described specific position in the transport direction of the substrate P.

  As shown in FIG. 5, the alignment microscopes AMG1 and AMG2 have a plurality of (for example, four) detection probes arranged in a line in the Y-axis direction (the width direction of the substrate P). The alignment microscopes AMG1 and AMG2 are detection probes at both ends of the second drum member 22 in the Y-axis direction, and can always observe or detect alignment marks formed near both ends in the width direction of the substrate P. The alignment microscopes AMG1 and AMG2 are detection probes other than both side ends in the Y-axis direction (the width direction of the substrate P) of the second drum member 22. For example, a plurality of alignment microscopes AMG1 and AMG2 are formed on the substrate P along the longitudinal direction. It is possible to observe or detect an alignment mark formed in a margin or the like between the pattern formation areas of the display panel.

  As shown in FIG. 5, lines passing through the centers (detection centers) of the observation areas on the substrate P by the alignment microscopes AMG1 and AMG2 and orthogonal to the second central axis AX2 are taken as observation azimuth lines AM1 and AM2. In this case, each observation azimuth line AM1 of the four alignment microscopes AMG1 is parallel to the Y axis direction, and similarly, each observation azimuth line AM2 of the four alignment microscopes AMG2 is parallel to the Y axis direction.

  As shown in FIGS. 5 and 6, when viewed in the XZ plane, the installation azimuth line Le4 of the encoder head EN4 is set to the same azimuth as each observation azimuth line AM1 of the four alignment microscopes AMG1. Further, the installation direction line Le5 of the encoder head EN5 is set to the same direction as each observation direction line AM2 of the four alignment microscopes AMG2.

  Thus, the detection probes of the alignment microscopes AMG1 and AMG2 are disposed around the second drum member 22 as viewed from the second central axis AX2. The detection probes of the alignment microscopes AMG1 and AMG2 have a direction (installation orientation Le4 and Le5) connecting the position at which the encoder heads EN4 and EN5 are arranged and the second central axis AX2 with the second central axis AX2 and the alignment microscope It is arranged to coincide with the direction connecting the detection centers of AMG1 and AMG2. In addition, a rotation center line on which encoder heads EN4 and EN5 corresponding to respective observation areas (detection centers) of alignment microscopes AMG1 and AMG2 and encoders EN1 and EN2 corresponding to projection areas PA1 to PA6 of projection modules PL1 to PL6 are arranged. The position in the circumferential direction of AX2 is set between a sheet entry area IA where the substrate P starts to contact the second drum member 22 and a sheet detachment area OA where the substrate P is released from the second drum member 22, as shown in FIG. Ru.

  The alignment microscopes AMG1 and AMG2 are arranged in front of the exposure position (projection area PA). In the alignment microscopes AMG1 and AMG2, for example, the substrate P sends an image of an alignment mark (formed in a region of several tens of μm to several hundreds of μm square) formed near the end of the substrate P in the Y direction. In this state, image detection (sampling) is performed at high speed by an imaging element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). At the moment when the sampling is performed, the control device 14 stores (latches) the rotational angle position of the encoder scale disc SD sequentially measured by the encoder head EN4 so that the mark position on the substrate P and the second drum member The correspondence with the 22 rotational angle positions is obtained.

  If the mark detected by the alignment microscope AMG1 is also detected by the subsequent alignment microscope AMG2, the expansion and contraction of the substrate P and a slight slip on the second drum member 22 can also be measured. When the alignment microscope AMG1 samples a mark, the angular position aa1 measured by the encoder head EN4 and the angular position aa2 measured by the encoder head EN5 when the alignment microscope AMG2 samples the same mark are stored.

  Note that the up / down counter (counter) connected to each of the two encoder heads EN4 and EN5 (and EN1, EN2, and EN3) and outputting a measurement value corresponding to the angular position is, for example, the outer periphery of the scale disk SD. It is assumed that an origin mark (not shown) engraved on the surface is simultaneously reset to zero at an instant or an arbitrary time detected by a specific encoder head (any one of EN1 to EN5). The difference value between the angular positions aa1 and aa2 thus obtained is compared with the opening angle 00 of the azimuth lines Le4 and Le5 of the two alignment microscopes AMG1 and AMG2 which are precisely calibrated in advance. When there is an error between the difference value (.PHI.a1 -.PHI.a2) and the opening angle .PHI.0, the substrate P is slightly on the second drum member 22 between the sheet entry area IA and the sheet detachment area OA. It may slip or may extend or contract in the feed direction (circumferential direction).

  Generally, the positional error at the time of patterning is determined according to the fineness and overlay accuracy of the device pattern formed on the substrate P. For example, a linear pattern of 10 μm width is accurately superimposed on the underlying pattern layer In order to perform combined exposure, only an error of a fraction or less, that is, a position error of about ± 2 μm in terms of the dimension on the substrate P is permitted. In order to realize such high-accuracy measurement, the measurement direction of the mark image by each alignment microscope AMG1 and AMG2 (the tangential direction of the second drum member 22 in the XZ plane) and the encoder heads EN4 and EN5. It is necessary to align with the measurement direction (peripheral tangent direction of the scale GP in the XZ plane) within the allowable angle error.

  As described above, the encoder heads EN4 and EN5 are arranged to coincide with the measurement direction of the alignment mark on the substrate P by the alignment microscopes AMG1 and AMG2 (the tangential direction of the circumferential surface of the second drum member 22). . Therefore, at the time of position detection of the substrate P (mark) by the alignment microscopes AMG1 and AMG2 (at the time of image sampling), the second drum member 22 (encoder scale disc SD) is orthogonal to the installation azimuth Le4 or Le5 in the XZ plane. Even in the case of shifting in the circumferential direction (tangential direction), highly accurate position measurement can be performed in consideration of the shift of the second drum member 22.

  In addition, if the scale pitch of scale GP is always constant, it is assumed that there is no speed unevenness in rotation, the change interval of each reading value of encoder heads EN1, EN2, EN3, EN4, EN5 (generation time of up / down pulse to counter) ) Is constant. However, deformation of the encoder scale disc SD when attaching the encoder scale disc SD to the second drum member 22, position (tilt) error when attaching the encoder heads EN1, EN2, EN3, EN4 and EN5, manufacture of the encoder scale disc SD An inherent error (pitch error of the scale itself, pitch unevenness due to eccentricity, deformation, etc.) may occur on the scale GP due to the accuracy of the time, the eccentricity at the time of attachment, etc. In addition, an inherent error may also occur in the scale GP, such as expansion and contraction of the encoder scale disc SD due to a temperature change during operation of the substrate processing apparatus 11 or the like. In the present embodiment, a measurement error associated with the inherent error of the scale GP that occurs due to the above-described cause is obtained. Then, based on the obtained measurement error, a correction map (correction amount data) for correcting the inherent error of the scale GP is created, and the respective read values (actual measurement values) of the plurality of encoder heads EN1 to EN5 are The correction is made on the basis of the correction map so that the measurement is made to cancel or reduce the measurement error due to the inherent error of the scale GP.

  In this embodiment, the correction map of the measurement error caused by the pitch error and pitch unevenness of the scale of the scale GP is disposed on the outer periphery of the scale disc SD mounted coaxially with the second drum member 22 as a cylindrical member. It is executed based on the actual measured values of the plurality of encoder heads. Here, the correction map is created by the encoder head EN4 as the first reading unit, the encoder head EN5 as the second reading unit, and the control device 14 as the correction unit and the map creation unit. In the present embodiment, for convenience, the encoder head EN4 is used as a first reading unit, and the encoder head EN5 is used as a second reading unit. However, the first reading unit and the second reading unit have at least two attachment angle intervals known in advance. It may be any encoder head.

  The control device 14 as the correction unit is a difference value (m4-m5) between a read value by the encoder head EN4 (counted by the counter m4) and a read value by the encoder head EN5 (counted by the counter m5) Alternatively, a difference value (K45−) obtained by subtracting a difference value (m4-m5) from a predetermined value (for example, a value corresponding to the number of graduations between them, K45) corresponding to the angular interval between encoder head EN4 and encoder head EN5. Based on m4 to m5), a pitch error of the graduation occurring over one circumference of the graduation GP is determined, for example, at predetermined angular positions from the origin position of the graduation GP. Then, the control device 14 stores data of scale pitch error for one rotation of the scale GP as a correction map, and based on the correction map, the read value of the encoder head EN4, the read value of the encoder head EN5 or another encoder The read values of the heads EN1 to EN3 are corrected.

  FIG. 7 is an enlarged view schematically showing the scale of the scale GP. FIG. 8 is a schematic view showing the positional relationship between the scale GP and the encoder heads EN4 and EN5. As shown in FIG. 7, the scale of the scale GP is configured by, for example, repeating a convex portion GPt having a rising portion GPa and a falling portion GPb and a concave portion GPU between the adjacent convex portions GPt. In the present embodiment, it is assumed that one protrusion GPt and one recess GPU are one unit of the scale GP, that is, one pitch of the scale. To simplify the description, each encoder head EN1 to EN5 outputs an up pulse U when reading the rising portion GPa of the scale and outputs a down pulse D when reading the falling portion GPb. .

  The scale of the scale GP is the distance SS1 from the rising portion GPa to the rising portion GPa of the adjacent scale GP or the distance SS2 from the falling portion GPb to the falling portion GPb of the adjacent scale )become. Assuming that the graduation pitch defined at the time of design of the encoder scale disk SD is SS, the distance SS1 or SS2 will coincide with the graduation pitch SS at any part on the graduation GP, provided that the graduation GP is accurately manufactured. .

  Therefore, when the scale GP moves in the direction indicated by the arrow R in FIG. 7, if two up pulses U and one down pulse U are output, as seen by the pulses output by the encoder head EN, or When two down pulses D and one up pulse U are output, the outer peripheral surface (scale GP) of the encoder scale disc SD (see FIG. 6) moves (rotates) by the scale pitch SS. Become. If the type of pulse output from the encoder head EN is not distinguished, the outer peripheral portion of the encoder scale disc SD is moved by the scale pitch SS each time three pulses are detected.

  In actual encoder measurement, interpolation signal processing is performed to generate a two-phase signal (sin wave, cos wave) from the encoder head and further subdivide the graduation pitch SS based on the two-phase signal. . For this reason, the up pulse U and the down pulse D which are actually counted by the digital counter are generated at each position obtained by equally dividing the graduation pitch SS into a few to a few tenths.

  FIG. 8 schematically shows a plurality of graduations of the graduations GP provided on the outer peripheral portion of the scale disc SD, arranged linearly. In FIG. 8, it is assumed that the graduation GP provided on the outer peripheral portion of the encoder scale disc SD moves in the direction indicated by the arrow R. An encoder head EN4 as a first reading unit and an encoder head EN5 as a second reading unit are arranged in this order in the moving direction of the scale GP. The two encoder heads EN4 and EN5 move relatively in the direction opposite to the moving direction of the scale GP when viewed from the scale GP.

  As shown in FIG. 6, the pair of encoder heads EN4 and EN5 is a line connecting the encoder head EN4 and the second central axis AX2, a line connecting the encoder head EN4 and the second central axis AX2, and a line connecting the encoder head EN5 and the second central axis AX2. The central angle (encoder attachment angle) formed with (the installation orientation line Le5) is θs. Further, as shown in FIG. 8, the linear distance (the distance between the heads) in the circumferential direction of the scale GP at the position where the pair of encoder heads EN4 and EN5 read the scale GP on the surface of the encoder scale disc SD is XS.

  When the pair of encoder heads EN4 and EN5 are attached to the frame or the like of the substrate processing apparatus 11, the encoder attachment angle θs and the inter-head distance XS are constant. As described above, the scale pitch SS is equal to that of the encoder scale disc SD due to the deformation of the encoder scale disc SD, the manufacturing accuracy of the encoder scale disc SD, the eccentricity at the time of mounting, and the expansion and contraction of the encoder scale disc SD due to temperature change. In the circumferential direction, it is not necessarily constant. For example, as schematically shown in FIG. 8, in the areas a, c, d on the scale GP, the rising portion GPa stands between the one encoder mounting angle θs and the one head-to-head distance XS in the regions a, c, d. There are three graduations GP with one set of the falling portion GPb. However, there are 2.5 areas b and 6 graduations GP.

  In the example shown in FIG. 8, when the scale pitch SS is a design value, for example, between a single encoder attachment angle θs and one head-to-head distance XS, a specified number (three in this example) of scale GPs exist It shall be. In practice, the number of graduations GP existing between one encoder attachment angle θs and one head-to-head distance XS may increase or decrease from the above-described prescribed number due to the error factor of the graduations GP described above. In the area a in FIG. 8, the scale pitch is SSa, but in the area b, the scale pitch SSb of the area b is larger than the scale pitch SSa of the area a because the number of scales GP is smaller than the specified number. In addition, since the number of graduations GP in the region e is larger than the specified number, the graduation pitch SSe of the region e is smaller than the graduation pitch SSa.

  For example, it is assumed that the design graduation pitch SS is 100 and the design head-to-head distance XS is 300. In the areas a, c, and d in FIG. 8, the actual head-to-head distance X calculated based on the respective values (counts by the counter) obtained by reading the scale GP by the encoder heads EN4 and EN5 is 300. This corresponds to the design distance between heads XS. On the other hand, in the area b of FIG. 8, the actual inter-head distance X calculated based on the values (count values by the counter) read by the encoder heads EN4 and EN5 is 250, and the area e is the encoder head EN4. The actual head-to-head distance X based on the read value (count value by the counter) of EN5 is 600.

  Thus, the difference between the head-to-head distance XS and the actual head-to-head distance X in design is due to the scale pitch error of the scale GP. After fixing the pair of encoder heads EN4 and EN5 to the device, if the device is installed in a constant temperature environment, the distance between heads XS does not change. Therefore, for example, a map of scale pitch errors of the scale GP obtained from the read values of the encoder heads EN4 and EN5 based on the inter-head distance XS after fixing the encoder heads EN4 and EN5 (every angular position of 360 °) Create an error amount or an error correction amount) of After creating the map, map the amount of error or correction corresponding to the angular position based on the read value (count value of the counter) of the scale GP by the encoder head EN4, EN5 (or other heads EN1 to EN3) Can be corrected in real time by correcting the movement distance error of the scale GP in the circumferential direction.

When correcting the actual graduation pitch error and the movement distance error of the graduation GP, for example, the graduation pitch SS when there is no error in the graduation GP, the designed head distance XS and the actual head distance X, and further the graduation GP The actual scale pitch (actual scale pitch) SSr in the case where an error occurs in is calculated from, for example, equation (1). By using the actual scale pitch SSr, the error of the scale GP can be corrected, and as a result, the error of the moving distance of the scale GP can be corrected.
SSr = SS × XS / X (1)

Further, the error of the scale GP is corrected based on the number (scale lines of measurement) NS of the scale GP existing between the head distance XS read by the pair of encoder heads EN4 and EN5, and the movement distance error of the scale GP is It may be corrected. The number NS of the scale lines existing between the head distance XS can also be determined by the count value of the up pulse U and the down pulse D counter obtained from the pair of encoder heads EN4 and EN5. When the measuring graduation line NS is used, the actual graduation pitch SSr can be obtained by the equation (2) including the distance between heads XS.
SSr = XS / NS · · · (2)

  The error of the scale pitch and the error of the movement distance of the scale GP can be determined by the control device 14 as the correction unit of the position detection device of the cylindrical member, for example, by calculation using equation (1) or (2). It is applied as a correction amount to the reading value of the encoder heads EN4 and EN5. For this reason, the position detection device of the cylindrical member provided with the control device 14 and the substrate processing device 11 can use the error map or the correction map even if an error occurs in the scale pitch SS due to the deformation of the encoder scale disc SD provided with the scale GP. Since the error can be corrected substantially in real time by using it, it is possible to realize highly accurate position measurement (position measurement in the circumferential direction) for the encoder scale disc SD and the second drum member 22. Next, the correction of the scale pitch error and the movement distance error will be described.

  FIG. 9 is a flowchart showing a procedure for correcting scale pitch error. FIG. 10 is a view showing the relationship between the scale disk SD having a scale on the outer peripheral surface and the encoder heads EN4 and EN5. FIG. 11 is a diagram showing an example of the correction map. When correcting the scale pitch error of the scale GP, as shown in FIG. 10, the inter-head distance XS of the pair of encoder heads EN4 and EN5 is measured in advance and stored in the storage unit of the control device 14. The head-to-head distance XS is obtained at a position where the pair of encoder heads EN4 and EN5 read the graduation GP on the outer peripheral surface of the encoder scale disc SD. The position where the pair of encoder heads EN4 and EN5 read the scale GP can be a position where the encoder scale disc SD is a true circle and the encoder scale disc SD is not eccentric to the rotation center line AX2. . In this case, as shown in FIG. 10, on the curved surface Pd (the scale surface of the scale GP) curved at the radius (the distance from the center to the outer peripheral surface) ra of the design value of the encoder scale disk SD from the rotation center line AX2. The head distance XS between the encoder heads EN4 and EN5 is measured. In the example shown in FIG. 10, the graduation GP of the encoder scale disc SD rotates (pivots) in the direction indicated by the arrow R, that is, from the encoder head EN4 toward the encoder head EN5.

  As shown in FIG. 9, when the process of the substrate processing apparatus 11 shown in FIG. 1 is not started in step S101 (step S101, No), the correction of the scale GP or the like is not performed. In step S101, when the processing of the substrate processing apparatus 11 is started and the scale disk SD is rotating stably (Yes in step S101), in step S102, the control device 14 performs encoder heads EN4 and EN5 at predetermined timing. Get these readings (Count value of counter) from. Acquisition at a predetermined timing means, for example, that the control device 14 reads each of the encoder heads EN4 and EN5 each time the graduation GP of the encoder scale disk SD rotates by a predetermined angle α (degrees) around the rotation center line AX2. Obtaining a value, ie, latching and storing the count value of each counter. Hereinafter, the angle α may be referred to as a rotation angle α as appropriate. When the encoder scale disc SD is rotating at an equal angular velocity (equal circumferential speed), the control device 14 may acquire the read values of both encoder heads EN4 and EN5 every predetermined time t. In this example, α (degree) is preferably a divisor of 360, but the angle α is not limited to this. The angle α is determined according to the tendency of the scale pitch error (the swing width of the error or the rate of change in the circumferential direction).

  If the encoder scale disc SD is rotating at a constant angular velocity, the controller 14 obtains these readings from both encoder heads EN4, EN5 every time t. When the control device 14 obtains these read values from both encoder heads EN4 and EN5 at predetermined angles α, for example, a rotation angle detection means of the encoder scale disc SD is prepared. Then, the control device 14 acquires these read values from both encoder heads EN4 and EN5 at each timing when the rotation angle detection means detects that the encoder scale disk SD has rotated by the angle α. Also, either one of both encoder heads EN4 and EN5 may be used as a rotation angle detection means. For example, when the encoder head EN4 is used as the rotation angle detection means, the control device 14 detects both the encoder heads EN4 and EN5 at every timing when the encoder head EN4 detects that the encoder scale disc SD has rotated by the angle α. Get these readings. The rotation of the encoder scale disk SD by the angle α can be detected, for example, by the encoder head EN4 detecting the number of graduations GP corresponding to the rotation angle α and outputting the number of pulses corresponding thereto.

  Next, in step S103, the control device 14 obtains an actual scale pitch SSr as a correction value of the scale GP based on the read value acquired in step S102. For example, in the case of obtaining the actual scale pitch SSr using the above-mentioned equation (2), the control device 14 obtains the measurement scale number NS from the read values of the encoder heads EN4 and EN5. The measurement scale number NS is a difference (NSa−NSb) between the reading value NSa of the number of graduations GP by the encoder head EN4 and the reading value NSb of the number of graduations GP by the encoder head EN5. Then, the control device 14 reads the head-to-head distance XS stored in its own storage unit, and obtains the actual scale pitch SSr from the equation (2). The actual scale pitch SSr is a correction value of the interval of the scale GP in the range of the angle α (degrees). When the actual scale pitch SSr is determined using the above-mentioned equation (2), the measurement encoder distance X is determined from the product of the measurement scale number NS and the scale pitch SS when there is no error in the scale GP. The number of measurement scales NS may be obtained from the distance XS, the scale pitch SS, and the distance X between measurement encoders.

  The measurement scale number NS can be determined, for example, as follows. When the encoder head EN4 reads a reference position (scale reference position) GPb of a plurality of graduations GP of the encoder scale disc SD, the control device 14 resets the encoder head EN4 (0 due to the Z phase of the encoder head EN4). After point reset), the number of graduations GP detected by the encoder head EN4 is counted. Next, when the encoder head EN5 reads the scale reference position GPb, the control device 14 resets the encoder head EN5 (0 point reset by the Z phase of the encoder head EN5). Then, the control device 14 obtains the number of graduations GP of the encoder head EN4 when the encoder head EN5 is reset to 0, and the number of graduations GP when the encoder head EN5 reads the scale reference position GPb, ie 0 Find the difference with. This difference is the number of measurement scales NS. After this, the control device 14 continues counting the scale GP by the encoder heads EN4 and EN5, and counts the readings of both encoder heads EN4 and EN5 at a predetermined angle α or a predetermined time t The count value of GP) is acquired, the difference is determined, and this is taken as the measurement scale number NS at the predetermined angle α or the predetermined time t. In this example, when the encoder scale disc SD makes one rotation, the scale reference position GPb returns to the original position, but at this time, the counters connected to each of the encoder heads EN4 and EN5 may not be reset, You may

  When the actual graduation pitch SSr (corresponding to the correction value of the graduation GP) at a certain angle α is obtained in step S103, the control device 14 associates the correction scale TBc shown in FIG. 11 with the angle α in step S104. Describe. For example, No. 1 of the correction map TBc. In 2, an angle 2 × α and a corresponding actual scale pitch SSr2 (= XS / NS2) are described. The correction map TBc is stored in the storage unit of the control device 14. The controller 14 determines the actual scale pitch SSr over the entire circumference of the plurality of graduations GP (the entire circumference of the encoder scale disc SD). The control device 14 corrects the correction value corresponding to the angle of the encoder scale disc SD detected by at least one of the encoder head EN4 and the encoder head EN5 during processing of the substrate processing apparatus 11, that is, the actual scale pitch SSr from the correction map TBc. Read out and correct the error of scale GP. As shown in FIG. 6, when the substrate processing apparatus 11 has three or more encoder heads EN1, EN2, EN3, EN4 and EN5, the control device 14 also uses the correction map TBc for other than the encoder heads EN4 and EN5. The error of the graduation GP may be corrected. Next, the process proceeds to step S105, and when the processing of the substrate processing apparatus 11 is not completed (No at step S105), the control device 14 continues the steps S102 to S104, and the processing of the substrate processing apparatus 11 If it has ended (Step S105, Yes), the control device 14 ends the correction of the scale GP and the like.

  In the above-described example, during processing of the substrate processing apparatus 11, that is, when the processing unit is performing predetermined processing (for example, exposure processing) on the substrate, the control device 14 has an appearance that the intervals of the plurality of graduations GP are apparent. Correct the above to be constant. By doing this, it is possible to correct in real time the error of the scale GP generated during the operation of the substrate processing apparatus 11, that is, the error of the reading scale interval, so that the processing accuracy of the substrate processing apparatus 11 is improved.

  When the disk SD performs one rotation, that is, when the scale reference position GPb at the position of the encoder head EN4 returns to the position of the encoder head EN4, the actual scale pitch SSr is determined as the correction value of the scale GP for the entire circumference. . After that, the controller 14 may similarly correct the scale GP every time the disc SD makes one revolution, and after the disc SD makes one revolution, the correction of the scale GP ends and predetermined timing (for example, a predetermined time) The correction of the scale GP may be resumed after a lapse of time or when a predetermined temperature change occurs. In the former case, since the correction map TBc is updated as needed, it is possible to rapidly cope with deformation or dimensional change of the encoder scale disc SD and the scale GP in a short time. In the latter case, the frequency of updating the correction map TBc can be suppressed, and accordingly, the hardware resources of the control device 14 can be used effectively.

  When the control device 14 acquires these read values from the encoder heads EN4 and EN5, the correction accuracy of the scale GP improves as the acquisition timing is shorter or the interval between the encoder heads EN4 and EN5 is smaller. The distance between the encoder heads EN4 and EN5 is subject to a certain degree of restriction from the balance between the size of the encoder heads EN4 and EN5 and the arrangement of other components. Therefore, shortening the timing when acquiring these read values from the encoder heads EN4 and EN5 has an advantage that versatility is enhanced.

  12 and 13 are conceptual diagrams showing timings when obtaining these read values from the pair of encoder heads. In the example described above, the control device 14 reads these readings from the encoder heads EN4 and EN5 each time the plurality of graduations GP of the encoder scale disk SD rotates by the predetermined rotation angle α (degrees) about the rotation center line AX2. I got When the rotation angle α (degree) at this time is a divisor of 360, while the encoder scale disk SD rotates a plurality of times, the encoder heads EN4 and EN5 read the same position every circumference (see FIG. 12). ). In this case, in order to improve the correction accuracy of the scale GP, it is necessary to reduce the predetermined rotation angle α, but due to the restriction of the device, etc., it is not possible to reduce the rotation angle α in darkness.

  In this embodiment, since the encoder scale disc SD having a plurality of graduations GP is a rotating body (continuous body), continuous measurement can be performed using the encoder heads EN4 and EN5 without necessarily securing the periodicity for each rotation. It is. Therefore, for example, by setting the rotation angle α (degree) not to be a divisor of 360 degrees, the periodicity of the reading position of the encoder heads EN4 and EN5 is broken when the encoder scale disc SD rotates a plurality of times. Can. In particular, by setting α (degree) to a number and a prime number that does not become a divisor of 360 degrees, the periodicity described above can be broken more effectively. As a result, even if the predetermined rotation angle α is large, the amount of displacement generated each time the multiple graduations GP (encoder scale disk SD) repeat laps becomes small, and as a result, the graduations GP by the encoder heads EN4 and EN5 The measurement interval can be reduced (see FIG. 13).

  For example, the angle α may be a value that does not become a divisor of 360 degrees between about 10 degrees and 35 degrees, but the value of 360 / α is about one to four decimal places, preferably one decimal place The value may be divisible by 4 digits. As an example, when the angle α is a prime number such as 11 degrees, 17 degrees, 19 degrees, 23 degrees, 360 / α can not be divided even by four digits after the decimal point. On the other hand, when the angle α is any one of 12.5 degrees, 16 degrees, 25 degrees, and 28.8 degrees, 360 / α is divisible by one decimal place. When the angle α is 19.2 degrees and 32.0 degrees, 360 / α is divisible by two decimal places. When the angle α is 12.8 degrees, 360 / α is divisible by three decimal places. Further, when the angle α is 25.6 degrees, 360 / α is divisible by 4 decimal places. In addition, the angle which becomes a divisor (360 / α is an integer) when the rotation angle α is between 10 degrees and 35 degrees is 10 degrees, 12 degrees, 14.4 degrees, 15 degrees, 18 degrees, 20 degrees, 22 .5 degrees, 24 degrees, 30 degrees. Although the rotation angle α may be in the range of 1 degree to 10 degrees, when avoiding a divisor such that 360 / α is an integer, the rotation angle α is 7 degrees and 9 degrees. Depending on the resolution of the required error correction, the rotation angle α is less than 1 degree, for example, 0.5 degrees, and the difference between the read values by each of the encoder heads EN4 and EN5 is obtained to create a map of the pitch error. May be

  FIG. 14 is a flow chart showing the procedure for correcting the scale error. In the example shown in FIG. 14, each of the plurality of graduations GP of the encoder scale disc SD rotates by a predetermined angle α (degrees) around the rotation center line AX 2 when the pair of encoder heads EN 4 and EN 5 read them. The processing procedure in the case where the rotation angle α is a prime which is not a divisor of 360 is shown. In this example, the rotation angle α may be, for example, 7 degrees, 11 degrees, or the like.

  Steps S201 to S204 are similar to steps S101 to S104 in the above-described example in which α (degree) is a divisor of 360, and thus the description will be omitted. In step S205, when the encoder scale disk SD has not rotated to the prescribed rotation number since the control device 14 starts obtaining the correction value (No in step S205), the steps S202 to S205 are repeated. In step S205, when the encoder scale disc SD has rotated to a prescribed rotational speed since the control device 14 starts obtaining the correction value (step S205, Yes), the process proceeds to step S206. Step S206 is the same as step S105 in the above-described example in which α (degree) is a divisor of 360, and therefore the description thereof is omitted. The specified number of rotations in step S205 may be two or more, but as the specified number of rotations increases, the effect of improving the correction accuracy of the scale GP decreases. For this reason, it is preferable to set a prescribed number of rotations within an appropriate range of two or more rotations.

  Next, the arrangement of the encoder heads EN4 and EN5 will be described. As shown in FIG. 6, the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit are the second drum members as cylindrical members rather than the exposure apparatus EX (see FIG. 1) as the processing unit. It is preferable to arrange on the opposite side to the rotation direction of 22. More specifically, it is preferable that the substrate P supported by the second drum member 22 be disposed on the opposite side of the rotation direction of the second drum member 22 than the portion to be exposed by the exposure apparatus EX. That is, the scale GP is read at two places before the portion where the substrate P supported by the second drum member 22 is subjected to the exposure processing by the exposure apparatus EX, and the correction value is obtained. In the example shown in FIG. 6, the rotation direction of the second drum member 22 is the direction from the encoder head EN4 toward the encoder head EN5. By arranging the encoder heads EN4 and EN5 in this manner, feedback to control of processing (exposure processing in this example) is performed using positional information in the circumferential direction of the second drum member 22 after the graduation GP is corrected. Processing accuracy is improved.

  In the present embodiment, both of the encoder heads EN4 and EN5 are disposed on the side opposite to the rotation direction of the second drum member 22 than the portion where the substrate P is exposed by the exposure apparatus EX. You may arrange | position to the part by which exposure processing is carried out. For example, the encoder head EN5 may be a first reading unit, the encoder head EN1 may be a second reading unit, and the correction value of the scale GP may be obtained based on the difference between the read values of the two.

  Further, in the present embodiment, since the alignment microscopes AMG1 and AMG2 are arranged at positions corresponding to the encoder heads EN4 and EN5, the processing position is obtained by measuring the change in the surface of the substrate P with the alignment microscopes AMG1 and AMG2. It is also possible to predict the change in the substrate P at the time of correction and correct it during processing. Further, in addition to the encoder heads EN4 and EN5, deflection of the rotation center line AX2 (orthogonal to the rotation center line AX2) is performed using at least one of the encoder heads EN1 and EN2 arranged at different positions, for example, processing positions. Motion in the direction of movement, roundness (shape distortion), eccentricity of the second drum member 22 or the like may be measured, and the process may be corrected based on the measured value.

  In the case of measuring the deflection of the rotation center line AX2 or the eccentricity of the second drum member 22 or the like, as a third reading unit disposed on the opposite side to the encoder heads EN4 and EN5 with respect to the processing position (position of exposure processing) The encoder head EN3 (see FIG. 6) is preferably used together with the encoder heads EN4 and EN5. In this way, measurement results such as shake of the rotation center line AX2 can be compared before and after the processing position, and an intermediate value can be used as a correction value for the shake of the rotation center line AX2. In addition, the shake or the like of the rotation center line AX2 is measured using encoder heads EN4 and EN5 and the encoder head EN3 arranged at the front and back of the processing position, and the rotation center line is corrected based on the measured values. The accuracy in correcting the shake of AX2 is improved. When the encoder head EN3 is used as a third reading unit, a straight line connecting the encoder head EN5 and the rotation center line AX2 (placement line Le5) and a straight line connecting the encoder head EN3 and the rotation center line AX2 (placement line Le3) The angle formed by is not limited to 210 degrees shown in FIG. 6, and the encoder head EN3 may be on the processing position side.

  When using the encoder head EN3 as the third reading unit in addition to the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit, the encoder head EN4 and the encoder head EN5 in the circumferential direction of the encoder scale disc SD It is preferable that the distance between them be smaller than the distance between the encoder head EN5 and the encoder head EN3. By narrowing the distance between the encoder head EN4 and the encoder head EN5, the correction accuracy of the scale GP can be improved. Further, by widening the distance between the encoder head EN5 and the encoder head EN3, the sensitivity at the time of detecting the eccentricity or the like of the second drum member 22 can be improved.

  Next, the intervals at which the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit are arranged will be described. The encoder head EN4 and the encoder head EN5 are formed by a line (installation azimuth line Le4) connecting the encoder head EN4 and the rotation center line AX2 and a line (installation azimuth line Le5) connecting the encoder head EN5 and the rotation center line AX2. It is preferable that the encoder attachment angle θs, which is a central angle, be arranged to be an angle other than 90 degrees, 180 degrees, and 270 degrees. By doing this, it is possible to detect the swing of the rotation center line AX2, the eccentricity of the second drum member 22, and the like by the two encoder heads EN4 and EN5. Further, the encoder attachment angle θs is preferably 45 degrees or less, and is preferably an angle other than 120 degrees and 240 degrees. By doing this, the correction accuracy of the scale GP is improved while detecting the swing of the rotation center line AX2, the eccentricity of the second drum member 22, and the like with the two encoder heads EN4 and EN5. Next, the case where the substrate processing apparatus 11 has a mechanism for adjusting the roundness of the encoder scale disc SD will be described.

  FIG.15 and FIG.16 is explanatory drawing for demonstrating the roundness adjustment mechanism which adjusts the roundness of an encoder scale disc. In FIG. 4 and FIG. 5 described above, although the diameter of the encoder scale disc SD is illustrated to be smaller than the diameter of the second drum member 22, the outer periphery of the outer peripheral surface of the second drum member 22 around which the substrate P is wound It is preferable that the diameter of the surface and the diameter of the graduation GP of the encoder scale disc SD be made to coincide (approximately match). By doing this, the so-called measurement Abbe error can be further reduced. In this case, the exposure apparatus EX preferably includes a roundness adjusting mechanism Cs for adjusting the roundness of the encoder scale disc SD as shown in FIG.

  The encoder scale disc SD, which is a scale member, is an annular member. An encoder scale disc SD having a scale GP on the outer peripheral surface is fixed to at least one end of the second drum member 22 orthogonal to the second central axis AX2 of the second drum member 22. The encoder scale disc SD has a groove Sc provided on the encoder scale disc SD along the circumferential direction of the second central axis AX2, and has a radius equal to that of the groove Sc and a second drum along the circumferential direction of the second central axis AX2. The groove Dc provided in the member 22 is opposed to the groove Dc. The encoder scale disc SD interposes a bearing member SB such as a rolling element (for example, a ball) between the groove Sc and the groove Dc.

  The roundness adjusting mechanism Cs is provided on the inner peripheral side of the encoder scale disc SD, and includes an adjusting member 60 and a pressing member PP. The roundness adjusting mechanism Cs is, for example, a pressing mechanism capable of changing the pressing force in the direction from the second central axis AX2 toward the scale GP, which is a direction parallel to the installation azimuth Le4. A plurality of (for example, eight places) are provided at a predetermined pitch in the circumferential direction. The adjusting member 60 has a male screw 61 inserted through the pressing member PP and screwed into the female screw FP3 of the encoder scale disc SD and the female screw FP4 of the second drum member 22, and a head 62 contacting the pressing member PP. Have. The pressing member PP is an annular fixed plate having a smaller radius than the encoder scale disc SD along the circumferential direction at the end of the encoder scale disc SD. The encoder scale disc SD is mounted on at least one end of the second drum member 22 in the circumferential direction of the second drum member 22 by the adjustment members 60 including a plurality of fastening members, that is, the male screw 61 and the head 62. It is fixed.

  At the point where the installation azimuth line Le4 is extended to the inner peripheral side of the encoder scale disk SD, the inclined surface FP2 is a cross section parallel to the second central axis AX2 and including the second central axis AX2 on the inner peripheral side of the encoder scale disk SD. Is formed. The inclined surface FP2 is an inclined surface in which the thickness in the direction parallel to the second central axis AX2 decreases as the second central axis AX2 is approached. An inclined surface FP1 is formed on the pressing member PP such that the thickness in the direction parallel to the second central axis AX2 increases as the second central axis AX2 is approached. The pressing member PP is fixed by the adjusting member 60 so that the inclined surface FP2 and the inclined surface FP1 face the encoder scale disc SD.

  By screwing the male screw portion 61 of the adjusting member 60 into the female screw portion FP3 of the encoder scale disk SD, the pressing force of the inclined surface FP1 of the pressing member PP is transmitted to the inclined surface FP2 by the roundness adjusting mechanism Cs. A small amount of elastic deformation occurs from the inner side to the outer peripheral side of the disc SD. Conversely, by rotating the male screw portion 61 to the opposite side, the suppressed pressing force of the inclined surface FP1 of the pressing member PP is transmitted to the inclined surface FP2, and a small amount is directed inwardly from the outer peripheral side of the encoder scale disc SD. Elastically deform.

  The roundness adjustment mechanism Cs adjusts the circumferential diameter of the scale GP by a small amount by operating the male screw portion 61 in the adjustment member 60 provided with a plurality of predetermined pitches in the circumferential direction around the rotation center line AX2 can do. Further, since the roundness adjusting mechanism Cs can minutely deform the graduation GP on the installation azimuth lines Le1 to Le5 described above, the diameter of the graduation GP in the circumferential direction can be adjusted with high accuracy. Therefore, by operating the adjustment member 60 at an appropriate position according to the roundness of the encoder scale disc SD, the roundness of the scale GP of the encoder scale disc SD can be increased, or a slight eccentricity error with respect to the rotation center line AX2. The position detection accuracy in the rotational direction with respect to the second drum member 22 can be improved. The adjustment amount adjusted by the roundness adjustment mechanism Cs varies depending on the diameter of the encoder scale disc SD or the radial position of the adjustment member 60, but is at most about several μm.

  As shown in FIG. 16, the encoder scale disc SD is fixed to the second drum member 22 by eight adjustment members 60. In this case, the encoder mounting angle θs, which is a central angle between the encoder head EN4, the second central axis AX2, and the encoder head EN5, is the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit. It is preferable to arrange so that it may become smaller than central angle (beta) which the adjacent adjustment member 60 and 2nd central axis AX2 make.

  Since the encoder scale disc SD is fixed to the second drum member 22 by the adjustment member 60, deformation may occur in the vicinity of the adjustment member 60. As described above, by setting θs <β, the encoder heads EN4 and EN5 can reliably detect the error of the graduation GP due to the deformation between the adjacent adjustment members 60. As a result, the correction accuracy of the scale GP is improved. Next, a modified example of the substrate processing apparatus (exposure apparatus) will be described.

(First modified example of substrate processing apparatus (exposure apparatus))
FIG. 17 is a schematic view showing a first modified example of the substrate processing apparatus (exposure apparatus). FIG. 18 is an explanatory view for explaining the position of the reading device when the encoder scale disk according to the first modification of the substrate processing apparatus (exposure apparatus) is viewed in the direction of the rotation center line. In the embodiment described above, the case where the position in the circumferential direction of the second drum member 22 supporting the substrate P is detected is taken as an example. The present invention is not limited to this, and as in the exposure apparatus EX1 of the present modification, also in the case of detecting the position in the circumferential direction of the first drum member 21 holding the cylindrical mask DM, using the pair of encoder heads The error of the scale GP (scale) for detecting the position of the drum member 21 in the circumferential direction can be corrected.

  The encoder scale disc SD included in the exposure apparatus EX1 is fixed to both ends of the second drum member 22 orthogonal to the rotation axis AX2 of the second drum member 22. The graduations GP are provided on the outer circumferential surface of both encoder scale discs SD. For this reason, the graduations GP are disposed at both ends of the second drum member 22. Encoder heads EN <b> 1 to EN <b> 5 for reading the respective graduations GP are respectively disposed on both end sides of the second drum member 22.

  The first detector 25 (see FIG. 1) described in the above embodiment optically detects the rotational position of the first drum member 21 and is an encoder scale disc (scale member) of high roundness. It includes an SD and encoder heads EH1, EH2, EH3, EH4 and EH5 as reading devices. The encoder scale disc SD is fixed to at least one end (both ends in FIG. 16) of the first drum member 21 orthogonal to the rotation axis of the first drum member 21. Thus, the encoder scale disc SD rotates integrally with the rotation axis ST around the rotation center line AX1. A scale GPM is engraved on the outer peripheral surface of the encoder scale disc SD. The encoder heads EH1, EH2, EH3, EH4, EH5 are arranged around the graduation GP as viewed from the rotation axis STM. The encoder heads EH1, EH2, EH3, EH4 and EH5 are disposed opposite to the graduation GPM, and can read the graduation GPM without contact. The encoder heads EH1, EH2, EH3, EH4, and EH5 are disposed at different positions in the circumferential direction of the first drum member 21. The first drum member 21 rotates from the encoder head EH4 toward the encoder head EH5.

  The encoder heads EH1, EH2, EH3, EH4, and EH5 are reading devices having measurement sensitivity (detection sensitivity) with respect to displacement variations in the tangential direction (in the XZ plane) of the scale GPM. As shown in FIG. 17, when the installation azimuths (angular directions in the XZ plane around the rotation center line AX1) of the encoder heads EH1 and EH2 are represented by installation azimuths Le11 and Le12, the installation azimuths Le11 and Le12. The encoder heads EH1 and EH2 are disposed such that the angle .theta. The installation azimuth lines Le11 and Le12 coincide with the angular direction in the XZ plane centering on the rotation center line AX1 of the illumination light flux EL1 shown in FIG. Here, the illumination mechanism IU, which is a processing unit, performs a process of transmitting the illumination light beam EL1 through a predetermined pattern (mask pattern) on the cylindrical mask DM, which is an object to be processed. Thereby, the projection optical system PL can project the image of the pattern in the illumination area IR on the cylindrical mask DM onto a part (projection area PA) of the substrate P being transported by the transport device.

  The encoder head EH4 rotates by approximately 90 degrees about the axis of the rotation center line AX1 of the installation azimuth line Le11 of the encoder head EH1 toward the rear side in the rotational direction with respect to the center plane P3 of the first drum member 21 It is set on line Le14. Further, the encoder head EH5 is installed by rotating the installation direction line Le12 of the encoder head EH2 about the axis of the rotation center line AX1 toward the rear side in the rotational direction about the center plane P3 of the first drum member 21 It is set on the azimuth line Le15. Here, in the case where approximately 90 ° is 90 ° ± γ, the range of γ is the same as that of the embodiment described above.

  Further, the encoder head EH3 rotates the installation azimuth line Le12 of the encoder head EH2 by approximately 120 ° around the axis of the rotation center line AX1, and rotates the encoder head EH4 approximately 120 ° around the axis of the rotation center line AX1. It is set on line Le13. The arrangement of the encoder heads EH1, EH2, EH3, EH4 and EH5 arranged around the first drum member 21 in the present embodiment is the encoder head EN1 arranged around the second drum member 22 in the embodiment described above. , EN2, EN3, EN4, and EN5 are mirror images of each other.

  As described above, the exposure apparatus EX1 is a first reading apparatus that reads the scale GP, the second drum member 22 which is a cylindrical member, the scale GP, the projection modules PL1 to PL6 which are the processing units of the exposure apparatus EX1. The encoder heads EN4 and EN5 and encoder heads EN1 and EN2 which are second reading devices for reading the graduation GP.

  The first drum member 21 has a curved surface curved at a constant radius from a first central axis AX1 which is a predetermined axis, and rotates around the first central axis AX1. The graduations GPM are annularly arranged along the circumferential direction of the first drum member 21 and rotate with the first drum member 21 around the first central axis AX1. The illumination mechanism IU, which is a processing unit of the exposure apparatus EX1, is a substrate P which is disposed inside the first drum member 21 as viewed from the second central axis AX2 and which has a curved surface at a specific position in the circumferential direction of the first drum member 21. A process of transmitting the two illumination light beams EL1 to (object to be processed) is performed. The encoder heads EH4 and EH5 are disposed around the scale GPM when viewed from the first central axis AX1, and the above-mentioned specific position is approximately 90 degrees around the first central axis AX1 around the first central axis AX1. It is placed at the rotated position and reads the tick mark GPM. The encoder heads EH1 and EH2 read the graduation GPM at the specific position described above. Then, the exposure apparatus EX1 corrects an error (pitch error) of the scale GPM provided on the outer peripheral portion of the encoder scale disc SD attached to the first drum member 21 based on the read values of the encoder heads EH4 and EH5. Therefore, the exposure apparatus EX1 can measure the position of the first drum member 21 in the circumferential direction with high accuracy, and process the object to be processed on the curved surface of the second drum member 22, that is, the substrate P. As described above, in the present embodiment, when the error is corrected based on the read values of the encoder heads EH4 and EH5, specifically, the control device 14 of the exposure apparatus EX includes the read value of the encoder head EH4 and the encoder head EH5. The pitch error is corrected on the basis of the difference from the read value of. However, when another encoder head is provided around the graduation GPM of the first drum member 21 at an installation angle close to either of the encoder heads EH4 and EH5, a direct difference between the readings of the encoder heads EH4 and EH5 Not limited to the calculation, it is also possible to obtain the pitch error by calculation based on the readings of the three encoder heads of the encoder heads EH4 and EH5 and the other encoder heads. The measurement of pitch errors by the three encoder heads will be described in detail later.

(Second Modified Example of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 19 is a schematic view showing an entire configuration of a second modified example of the substrate processing apparatus (exposure apparatus). In the exposure apparatus EX2, a light source device (not shown) emits an illumination light beam EL1 illuminated on the cylindrical mask DM. The illumination light beam EL1 emitted from the light source of the light source device is guided to the illumination module IL, and when a plurality of illumination optical systems are provided, the illumination light beam EL1 from the light source is split into a plurality of illumination lights EL1 Lead to the module IL.

  The illumination light beam EL1 emitted from the light source device is incident on the polarization beam splitters SP1 and SP2. In the polarization beam splitters SP1 and SP2, in order to suppress the energy loss due to the separation of the illumination light beam EL1, it is preferable to use a light flux that reflects all the incident illumination light flux EL1. Here, the polarization beam splitters SP1 and SP2 reflect light fluxes to be linearly polarized light of S polarization and transmit light fluxes to be linear polarized light of P polarization. For this reason, the light source device emits, to the first drum member 21, the illumination light flux EL1 in which the illumination light flux EL1 incident on the polarization beam splitters SP1 and SP2 is a light flux of linear polarization (S polarization). Thereby, the light source device emits the illumination light flux EL1 whose wavelength and phase are aligned.

  The polarization beam splitters SP1 and SP2 reflect the illumination light beam EL1 from the light source, while transmitting the projection light beam EL2 reflected by the cylindrical mask DM. In other words, the illumination beam EL1 from the illumination optical module ILM enters the polarization beam splitters SP1 and SP2 as a reflected beam, and the projection beam EL2 from the cylindrical mask DM enters the polarization beam splitters SP1 and SP2 as a transmitted beam. .

  As described above, the illumination module IL, which is the processing unit, performs a process of reflecting the illumination light beam EL1 on a predetermined pattern (mask pattern) on the cylindrical mask DM, which is the object to be processed. Thereby, the projection optical system PL can project the image of the pattern in the illumination area IR on the cylindrical mask DM onto a part (projection area) of the substrate P being transported by the transport device.

  When a predetermined pattern (mask pattern) for reflecting the illumination light beam EL1 is provided on the surface of the curved surface of such a cylindrical mask DM, a scale GPm can be provided on the curved surface along with the mask pattern. When this graduation GPm is formed simultaneously with the mask pattern, the graduation GPm is formed with the same accuracy as the mask pattern. Therefore, the image of the mark of the graduation GPm can be sampled at high speed and with high accuracy by the curved surface detection probes GS1 and GS2 that detect the graduation GPm. At the moment when this sampling is performed, the correspondence between the rotational angle position of the first drum member 21 and the scale GPm is determined, and the rotational angle position of the first drum member 21 measured sequentially can be stored.

  The encoder heads EH4 and EH5 on the cylindrical mask DM side read the graduation GPm. Then, the exposure apparatus EX2 corrects the error of the graduation GPm provided on the surface of the cylindrical mask DM based on the difference between the read values of the encoder heads EH4 and EH5. Therefore, the exposure apparatus EX2 can measure the position of the cylindrical mask DM in the circumferential direction with high accuracy, and process the substrate P on the curved surface of the second drum member 22.

  The encoder heads EN4 and EN5 on the second drum member 22 side read the graduation GPd of the encoder scale disc SD attached to the second drum member 22. Then, the exposure apparatus EX2 corrects the error of the scale GPd provided on the surface of the encoder scale disc SD based on the difference between the read values of the encoder heads EN4 and EN5. Therefore, the exposure apparatus EX2 can measure the position of the second drum member 22 in the circumferential direction with high accuracy, and process the substrate P on the curved surface of the second drum member 22.

(Third Modification of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 20 is a schematic view showing an entire configuration of a third modified example of the substrate processing apparatus (exposure apparatus). The exposure apparatus EX3 includes polygon scanning units PO1 and PO2 to which an exposure beam from a light source device (not shown) is incident, and the polygon scanning unit PO performs spot light intensity-modulated along the one-dimensional scanning line on the substrate P Scan. The exposure apparatus EX3 included in the substrate processing apparatus can irradiate a substrate P at a specific position with exposure light and draw a predetermined pattern even without the cylindrical mask DM.

  The encoder heads EN4 and EN5 on the second drum member 22 side of the exposure apparatus EX3 read the graduation GPd of the encoder scale disc SD attached to the second drum member 22. Then, the exposure apparatus EX2 corrects the error of the scale GPd provided on the surface of the encoder scale disc SD based on the difference between the read values of the encoder heads EN4 and EN5. Therefore, the exposure apparatus EX2 can measure the position of the second drum member 22 in the circumferential direction with high accuracy, and process the substrate P on the curved surface of the second drum member 22.

  As shown in FIG. 20 (and FIG. 19), the encoder heads EN4 and EN5 on the second drum member 22 side are arranged corresponding to each of two rows of alignment microscopes AMG1 and AMG2 in the circumferential direction. It was done. However, among the alignment microscopes AMG1 and AMG2, for example, only the alignment microscope AMG2 (and the corresponding encoder head EN5) may be arranged. Even in such a case, it is preferable to provide an encoder head EN4. When only the alignment microscope AMG2 (and the corresponding encoder head EN5) is disposed and the encoder head EN4 can not be installed at the rotation angle α in the vicinity thereof, using the encoder heads EN1 and EN2 disposed corresponding to the exposure position An error map such as a pitch error or eccentricity of the scale GPd of the disk SD may be created.

  Furthermore, at least one error map such as pitch error and eccentricity of scale GPd obtained using two encoder heads EN4 and EN5, pitch error and eccentricity of scale GPd obtained using two encoder heads EN1 and EN2, etc. By comparing with at least one error map of, and verifying whether there is a big difference between both error maps, if there is a difference more than the tolerance value, re-create the error map , Error map accuracy and reliability can be improved.

(Fourth Modified Example of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 21 is a schematic view showing an entire configuration of a fourth modified example of the substrate processing apparatus (exposure apparatus). The exposure apparatus EX4 is a substrate processing apparatus which subjects the substrate P to so-called proximity exposure. The exposure device EX4 sets the gap between the cylindrical mask DM and the second drum member 22 minutely, and the illumination mechanism IU directly irradiates the substrate P with the illumination light flux EL1 to perform non-contact exposure. In the present embodiment, the second drum member 22 is rotated by the torque supplied from the second drive unit 36 including an actuator such as an electric motor. For example, a driving roller MGG coupled by a magnetic gear drives the first drum member 21 so as to be reverse to the rotation direction of the second driving unit 36. The second drive unit 36 rotates the second drum member 22 and rotates the drive roller MGG and the first drum member 21 to synchronize the first drum member 21 (cylindrical mask DM) with the second drum member 22. Move (synchronize).

  The exposure apparatus EX4 further includes an encoder head EN6 that detects the position PX6 of the scale GP at a specific position where the principal ray of the imaging light beam EL2 enters the substrate P with respect to the substrate P. Here, since the diameter of the outer peripheral surface of the outer peripheral surface of the second drum member 22 to which the substrate P is wound and the diameter of the scale GP of the encoder scale disc SD are equalized, the position PX6 is from the second central axis AX2 It looks and matches the specific position mentioned above. The encoder head EN7 is set on the installation direction line Le7 rotated approximately 90 ° around the axis of the rotation center line AX2 of the installation direction line Le6 of the encoder head EN6 toward the rear side in the feed direction of the substrate P .

  The exposure apparatus EX4 sets, for example, an encoder head EN3 as a first reading unit and an encoder head EN7 as a second reading unit. The encoder heads EN3 and EN7 read the graduation GPd of the encoder scale disc SD attached to the second drum member 22. The controller 14 corrects the error of the graduation GPd provided on the surface of the encoder scale disc SD based on the difference between the readings of the encoder heads EN3 and EN7. Therefore, the exposure apparatus EX4 can measure the position of the second drum member 22 in the circumferential direction with high accuracy, and process the substrate P on the curved surface of the second drum member 22. The encoder heads EN3 and EN7 are encoders formed by a line connecting the encoder head EN3 and the second central axis AX2 (installation azimuth Le3) and a line connecting the encoder head EN7 and the second central axis AX2 (installation azimuth Le7) The mounting angle θs may be less than 90 degrees, preferably 45 degrees or less.

  The above-described embodiment and the first to fourth modifications of the substrate processing apparatus (exposure apparatus) exemplify the exposure apparatus as the substrate processing apparatus. The substrate processing apparatus is not limited to the exposure apparatus, and the processing unit may be an apparatus that prints a pattern on the substrate P, which is an object to be processed, by an ink drop apparatus of inkjet. Also, the processing unit may be an inspection device.

  By the way, in the explanation of the reading operation of the scale GP by the encoder heads EN4 and EN5 using FIG. 7 and FIG. 8 above, when the rising portion GPa of one scale of the scale GP is read, the up pulse U is output to stand up The down pulse D is output when the falling portion GPb is read, and the interval between two adjacent rising portions GPa or the interval between adjacent falling portions GPb is set as the pitch SS of the scale GP. However, in an actual encoder measurement system, as disclosed in, for example, Japanese Patent Laid-Open No. 9-196702, a sine wave having a phase difference of 90 degrees is output from a signal generator (encoder head). The up pulse U and the down pulse D are generated at intervals obtained by dividing the actual size pitch SS of the scale GP into a few to a few tenths of a signal and a cosine wave signal) by an interpolation circuit, a comparator or the like. Configured as.

  FIG. 22 briefly illustrates the actual reading operation of the scale GP (GPd, GPM) by the encoder heads EN1 to EN7 and EH1 to EH5 shown in FIGS. 4 to 6 and 10 and 16 to 21 respectively. Is a signal waveform diagram for As shown in FIG. 22, each of the encoder heads EN1 to EN7 and EH1 to EH5 outputs two measurement signals EcA and EcB (represented here by rectangular waves) having a phase difference of 90 degrees. One cycle of the measurement signals EcA and EcB corresponds to 1 / n of the pitch SS of the scale GP. Although n (integer) differs depending on the optical reading form in the encoder head, it is set to any value of a multiple sequence such as 1, 2, 4, 8,. In a normal encoder measurement system, while the scale disk SD rotates in the forward direction and the scale GP is always moved in one direction with respect to the encoder head, interpolation up is performed based on the measurement signals EcA and EcB. The pulse signal EcU continues to be generated. If the scale disk SD is reversed, a down pulse signal interpolated based on the measurement signals EcA and EcB continues to be generated from that time.

  In FIG. 22, a processing circuit is used which transmits an up pulse signal EcU (or down pulse signal EcD) which generates a pulse at intervals obtained by dividing one cycle of the measurement signals EcA and EcB into eight. When the up pulse signal EcU is input, the up / down counter as a counter sequentially counts up the number of pulses, and when the down pulse signal EcD is input, the number of pulses is sequentially counted down. Here, for example, assuming that one cycle of the measurement signals EcA and EcB corresponds to 1/8 of the actual pitch SS of the scale GP, the up-down counter is the scale surface of the scale disc SD (scale GP) in order While moving in the direction by one pitch SS, 64 pulses of the up pulse signal EcU are counted. Therefore, when the pitch SS of the graduation GP is 20 μm, the increment of the count value of one pitch by the up / down counter is 64, and the measurement resolution (the amount of movement per signal EcU of the signal EcU) of the encoder measurement system is 0. 3125 μm (20 μm / 64). As described above, the measurement resolution as the encoder measurement system is refined by interpolating the actual size of the pitch SS of the scale GP to a few to a few tenths, so the error of the pitch SS is It can be obtained with accuracy according to the degree of the interpolation.

  In addition, when it is set as a value obtained by dividing the circumferential long distance (diameter × π) of the scale surface of the scale disk SD by a finite number of graduations (number of lattices), the actual size of the pitch SS of the graduations GP is a fraction with respect to 20 μm. May accompany. On the other hand, the pitch SS is set so that the measurement resolution has a good value (for example, 0.25 μm) so that the circumferential long distance of the scale surface of the scale disk SD can be divided within the predetermined accuracy. The diameter of the scale surface may be set.

  By the way, on the scale surface such as the scale disk SD, an origin mark which is the origin of one rotation of the scale disk SD is engraved along with the scale GP, and each of the encoder heads EN1 to EN7 detects the origin mark At that moment, the origin signal (pulse) EcZ is output. In response to the origin signal EcZ, the up / down counter continues counting of the number of pulses of the up pulse signal EcU (or the down pulse signal EcD) after resetting the count value so far to zero. Therefore, each of the up / down counters provided corresponding to each of the encoder heads EN1 to EN7 is a pulse of the up pulse signal EcU (or down pulse signal EcD) with reference to the instant (zero point) at which the origin signal EcZ is received. The numbers are added (or subtracted).

  From the above, for example, when obtaining the pitch error of the graduation GP by the difference between the measurement values of each of the encoder head EN4 and the encoder head EN5, the scale disc SD (second drum member 22) is as shown in FIGS. As described above, it is only necessary to digitally calculate the difference between the count value of the up / down counter corresponding to the encoder head EN4 and the count value of the up / down counter corresponding to the encoder head EN5 each time it rotates by the angle α. Good. In addition, the count value of the up / down counter corresponding to one of the encoder head EN4 and the encoder head EN5 (or one other encoder head) may be increased by a fixed value corresponding to the angle α. It can be detected by determining whether (or decreased).

(Modification 1)
In the above embodiment and modification, the scale GP which constitutes the encoder measurement system is engraved on the cylindrical outer peripheral surface of at least one of the scale disc SD as the rotating body and the second drum member 22. However, the graduation GP may be formed at a predetermined pitch along the circumferential direction on the side end face perpendicular to the rotation center line AX2 of at least one of the scale disc SD and the second drum member 22. FIG. 23 is a view of the configuration in the case of forming the graduation GP on the side end face of the scale disc SD as seen from the direction (Y-axis direction) in which the rotation center line AX2 extends as in FIG. FIG. 24 is a cross-sectional view taken along the line AA 'of FIG. 23 taken along a plane including the installation direction line Le4 and the rotation center line AX2.

  In FIG. 23, the ring-shaped scale disc SD is attached to eight places on the side end face of the second drum member 22 by adjustment members (screws) 60. The mounting angle β of the adjustment member (screw) 60 is now 45 °. On the side surface parallel to the XZ plane of the scale disk SD, a scale GP with a constant pitch SS and an origin mark Zs are formed along the circumference from the rotation center line AX2 to the radius ra. The encoder heads EN4 and EN5 are arranged in the Y-axis direction so as to face the scale GP with a constant gap, as shown in FIG. As shown in FIG. 23, the reading position RP4 of the encoder head EN4 is set on the radius ra and on the installation azimuth line Le4. The reading position RP5 of the encoder head EN5 is set on the radius ra and on the installation azimuth Le5. The radius ra is a radius of the outer peripheral surface 22s which closely supports the substrate P of the second drum member 22, as shown in FIG. Therefore, the maximum diameter of the ring-shaped scale disc SD is set to be slightly larger than the radius ra. By arranging the scale disc SD and the encoder heads EN4 and EN5 in this manner, the Abbe error during measurement can be minimized. The other encoder heads (EN1 to EN3 and EN6 to EN7) for the ring-shaped scale disc SD in FIG. 23 and FIG. 24 are also arranged to satisfy the Abbe conditions of measurement, similarly to the heads EN4 and EN5.

(Modification 2)
In the above embodiment and modifications, the difference between the measurement values of each of two encoder heads (for example, encoder heads EN4 and EN5) arranged close to each other for measurement of the pitch error of the scale GP is a scale disk. Each time SD (the second drum member 22) rotates by an angle α (α <θs) is stored, and a map relating to the pitch error of the entire circumference of the scale disk SD is created. In that case, in order to improve the map accuracy, the angle θs formed by the reading position (corresponding to RP4 and RP5 in FIG. 23) on the scale surface of each of the two encoder heads (for example, encoder heads EN4 and EN5) It is preferable to make it as small as possible. However, the angle θs may not be reduced sufficiently depending on the external shape and dimensions of the encoder heads EN4 and EN5 or the angle between the orientation lines Le4 and Le5 determined by the arrangement of the alignment microscopes AMG1 and AMG2.

  Therefore, in the second modification, for example, three or more encoder heads EN1 (or EN2) disposed in the vicinity are added together with the two encoder heads EN4 and EN5 used for pitch error measurement in the previous embodiment. The measurements from each of the encoder heads are used to further refine the pitch error map. FIG. 25 is a view of the arrangement of the scale disk SD (here, ring-shaped) and the encoder heads EN1, EN2, EN4, and EN5 in the XZ plane, as in FIG. A scale GP and an origin mark Zs are formed along the outer peripheral surface of the SD. In addition, the scale disc SD is fixed to the side end surface of the second drum member 22 by the adjustment member (screw) 60 at 16 places in the circumferential direction. Accordingly, the mounting angle β of the adjustment member (screw) 60 is 22.5 °.

  As shown in FIG. 25, the encoder head EN1 has a reading position set on the installation azimuth line Le1 corresponding to the odd-numbered exposure position, and the reading position on the installation azimuth line Le2 corresponding to the even-numbered exposure position. The encoder head EN2 to be set is disposed at an angle ± θ with respect to the central plane P3 in the XZ plane. Further, the angles θs formed by the installation azimuth lines Le4 and Le5 passing through the reading positions of the encoder heads EN4 and EN5 are in a relationship of θs> β. Further, an angle between the installation azimuth line Le1 passing through the reading position of the encoder head EN1 and the installation azimuth line Le4 passing through the reading position of the encoder head EN4 is taken as θq. Further, the count values of the up / down counters provided corresponding to the encoder heads EN1, EN2, EN4, and EN5 are respectively Cm1, Cm2, Cm4, and Cm5.

  When the scale disk SD (second drum member 22) shown in FIG. 25 rotates clockwise in the XZ plane, the origin mark Zs formed on the scale surface of the scale disk SD is the encoder head EN4, EN5, EN1. , And in the order of EN2, the respective reading positions are crossed. Therefore, at the moment when the origin mark Zs crosses the reading position of the encoder head EN4, the corresponding up / down counter count value Cm4 is reset to zero and the moment when the origin mark Zs crosses the reading position of the encoder head EN5 The count value Cm5 of the up / down counter is reset to zero, and at the moment the origin mark Zs crosses the reading position of the encoder head EN1, the count value Cm1 of the corresponding up / down counter is reset to zero, and the origin mark Zs is of the encoder head EN2. At the moment when the reading position is crossed, the count value Cm2 of the corresponding up / down counter is reset to zero. When the scale disk SD rotates clockwise, the count values Cm1, Cm2, Cm4, and Cm5 after all the four up / down counters are reset to zero always have a relationship of Cm2 <Cm1 <Cm5 <Cm4. There is.

Therefore, in the case of creating an error map (correction map) by obtaining pitch errors using three encoder heads EN1 (count value Cm1), EN4 (count value Cm4), and EN5 (count value Cm5), a scale disk Every time the SD (second drum member 22) rotates by a fixed angle α (α <β <θs), a measured value ΔMs related to a pitch error for each unit angle α is obtained by the following equation (1). Although this measured value ΔMs corresponds to the number NS of the graduations GP shown in FIG. 11 described above, it is actually the count value of pulses of the up pulse (or down pulse) EcU shown in FIG. .
ΔMs = (Cm4 + Cm1) / 2-Cm5 formula (1)

  In this equation (1), the calculated value of (Cm4 + Cm1) / 2 is set to an angular position that is an intermediate point between the reading position RP4 of the encoder head EN4 and the reading position RP1 of the encoder head EN1, as shown in FIG. The virtual installation azimuth line Lei indicates the count value expected to be obtained when the reading position RPi of the encoder head is set. Therefore, the measured value ΔMs obtained by the equation (1) or (2) described later is the count value Cmi (calculated value) at the reading position RPi by the virtual encoder head and the reading position RP5 of the encoder head EN5. The difference with the count value Cm5 of A pitch error map or a pitch error correction map of a scale (scale GP) such as the scale disk SD can be created by obtaining the measurement value ΔMs for 360 degrees for each unit angle α.

  By the way, in the case of the arrangement as shown in FIG. 25, the count value Cm4 or the measurement value Cm5 is measured in a period in which the origin mark Zs passes between the reading position RP4 of the encoder head EN4 and the reading position RP1 of the encoder head EN1. Is after being reset to zero, there is a possibility that the continuity of the three count values Cm1, Cm4, and Cm5 can not be secured. In that period, the magnitude relationship between the count values Cm1, Cm4, and Cm5 (absolute value) is Cm4 <Cm1 <Cm5, or Cm5 <Cm4 <Cm1. Therefore, the maximum count value (fixed value) counted by the up-down counter from the time of zero reset to the time of the next zero reset is Cmf, and corresponds to each encoder head EN1, EN4, EN5 for each angle α. When reading the count values Cm1, Cm4 and Cm5, when the origin mark Zs is between the read position RP4 of the encoder head EN4 and the read position RP5 of the encoder head EN5, the maximum count value of the count value Cm4 of the up / down counter A new count Cm4 'to which Cmf is added may be used instead of the count Cm4 in the equation (1). Similarly, when the origin mark Zs is between the reading position RP5 of the encoder head EN5 and the reading position RP1 of the encoder head EN1, the maximum count Cmf is added to each of the counts Cm4 and Cm5 of the up / down counter. The count values Cm4 'and Cm5' may be used instead of the count values Cm4 and Cm5 in the equation (1).

  In the second modification, the first reading unit includes two encoder heads EN1 and EN4 (or one encoder head EN5), and the second reading unit includes one encoder head EN5 (or two encoder heads). It comprises EN1 and EN4). In the above configuration, when the angle θs and the angle θq are set to an appropriate relationship, the angle formed between the virtual reading position RPi and the reading position RP5 is the attachment angle β of the adjustment member (screw) 60 (22. in FIG. 25). The pitch error (pitch unevenness) due to slight deformation of the scale surface of the scale disc SD remaining after adjustment of roundness, eccentricity, etc. by the adjustment member 60 can be made smaller than 5 °) with a span of angle β or less It can be measured in detail.

Further, in the method of setting the virtual reading position RPi on the scale surface as described above, for example, it is set at the midpoint between the reading positions RP4 and RP1 of the two encoder heads EN4 and EN1 shown in FIG. Calculated from the calculated count value obtained at the virtual first reading position RPi and the virtual second reading position RPi set at the midpoint between the reading positions RP5 and RP2 of the two encoder heads EN5 and EN2. The pitch error may be determined by the difference from the calculated count value. The measurement value ΔMs for each unit angle α in that case is calculated by the following equation (2).
ΔMs = (Cm4 + Cm1) / 2- (Cm5 + Cm2) / 2 Formula (2)

(Device manufacturing method)
FIG. 26 is a flowchart showing the procedure of a device manufacturing method for manufacturing a device using the substrate processing apparatus (exposure apparatus) according to the embodiment. In this device manufacturing method, first, function / performance design of a display panel by self-light emitting elements such as organic EL is performed, and necessary circuit patterns and wiring patterns are designed by CAD (step S201). Next, based on the pattern of each of the various layers designed by CAD or the like, a cylindrical mask DM for the necessary layer is manufactured (step S202). In addition, a supply roll FR1 on which a flexible substrate P (a resin film, a metal foil film, a plastic or the like) to be a base material of the display panel is wound is prepared (step S203). The roll-like substrate P prepared in step S203 has its surface modified as necessary, a base layer (for example, minute unevenness by imprint method) formed in advance, photosensitive material It may be a laminate of a functional film or a transparent film (insulating material) in advance.

  Next, on the substrate P, a backplane layer composed of electrodes and wirings constituting the display panel device, an insulating film, a TFT (thin film semiconductor) and the like is formed, and organic EL etc. A light emitting layer (display pixel portion) is formed by the self light emitting element of the above (step S204). Although this step S204 includes the conventional photolithography process of exposing the photoresist layer using the exposure apparatuses EX, EX2, EX3 and EX4 described in the above embodiments, the photosensitivity is used instead of the photoresist. Pattern exposure of the substrate P coated with the silane coupling material to form a pattern of hydrophilicity and water repellency on the surface, pattern exposure of the photosensitive catalyst layer and pattern of a metal film by electroless plating (wiring, electrode Processing by a wet process of forming etc.) or a printing process of drawing a pattern with a conductive ink containing silver nanoparticles etc. is also included.

  Then, the substrate P is diced for each display panel device continuously manufactured on a long substrate P by a roll method, or a protective film (anti-environment barrier layer) or a color filter is formed on the surface of each display panel device. A sheet or the like is attached to assemble a device (step S205). Next, an inspection process is performed to determine whether the display panel device functions properly or satisfies the desired performance or characteristics (step S206). As described above, a display panel (flexible display) can be manufactured.

  In the above embodiment, a light transmission type reticle in which a predetermined light shielding pattern (or a phase pattern / light reduction pattern) is formed on a light transmitting substrate is used, but in place of this reticle, for example, US Pat. As described in US patent application Ser. No. 07 / 982,095, a variable-shaped reticle (also called an electronic reticle, an active reticle, or an image generator) that forms a transmission pattern or a reflection pattern or a light emission pattern based on electronic data of a pattern to be exposed. May be used. Further, instead of the variable-shaped reticle having the non-light emitting type image display device, a pattern forming apparatus including a self-light emitting type image display device may be provided.

  In addition, the exposure apparatus of the above embodiment is manufactured by assembling various sub-systems including the respective components recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy and optical accuracy. Be done. In order to ensure these various accuracies, before and after assembly of the exposure apparatus, adjustments for achieving optical accuracy for various optical systems, adjustments for achieving mechanical accuracy for various mechanical systems, various electric systems The system is tuned to achieve electrical accuracy. The process of assembling various subsystems into an exposure apparatus includes mechanical connection between the various subsystems, wiring connection of electric circuits, piping connection of air pressure circuits, and the like. It goes without saying that there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the process of assembling the various subsystems into the exposure apparatus is completed, comprehensive adjustment is performed to secure various accuracies as the entire exposure apparatus. It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature and the degree of cleanliness are controlled.

  Also, the components of the above embodiments can be combined as appropriate. In addition, some components may not be used. Furthermore, component replacements or changes can be made without departing from the scope of the present invention. Further, as far as the laws and regulations permit, the disclosures of all of the published publications and the U.S. Patents related to the exposure apparatus and the like cited in the above embodiments are incorporated herein by reference. Thus, all other embodiments, operation techniques, and the like made by those skilled in the art based on the above embodiments are included in the scope of the present invention.

11 substrate processing apparatus 14 control apparatus 21 first drum member 22 second drum member 25 first detector 35 second detector 60 adjustment member 61 male screw portion 62 head portion AX1 rotation center line (first center axis)
AX2 rotation center line (second center axis)
Cs Roundness adjustment mechanism DM Cylindrical mask EN, EN1, EN2, EN3, EN4, EN5, EH1, EH2, EH4, EH5 Encoder head EX, EX1, EX2, EX3, EX4 Exposure device GP, GPd, GPM, GPm Scale NS Measurement scale number P Substrate SD Encoder scale disc TBc correction map

Claims (9)

A substrate processing apparatus for transporting a flexible long sheet substrate in a longitudinal direction and performing predetermined processing on the sheet substrate,
A rotary drum for supporting the sheet substrate with a cylindrically curved outer peripheral surface at a constant radius from a center line, and for conveying the sheet substrate in a longitudinal direction by rotating around the center line;
A processing unit configured to process the sheet substrate at a specific position within a circumferential range supported by the outer peripheral surface of the rotary drum of the sheet substrate;
A scale graduation for providing an annular measurement along the circumferential direction in which the rotary drum rotates, and rotating around the center line with the rotary drum to measure an encoder position change in the circumferential direction of the sheet substrate;
A first encoder head arranged to face the scale marking in a first circumferential direction and reading the scale marking;
A second encoder head arranged to face the scale graduation in a second orientation rotated by an angle θq in a circumferential direction with respect to the first orientation, and reading the scale graduation;
Between the first orientation and the second orientation in the circumferential direction, the third orientation rotated by an angle θs in the circumferential direction with respect to the second orientation so as to face the scale graduation A third encoder head arranged to read the scale markings;
Assuming that the first reading value by the first encoder head is Cm1, the second reading value by the second encoder head is Cm4, and the third reading value by the third encoder head is Cm5, ΔMs = (Cm1 + Cm4) / 2− A storage unit which sequentially stores the measured value ΔMs calculated by Cm5 for each rotation of the scale scale at a predetermined angle α, and stores error information on a pitch error across the entire scale scale;
Substrate processing apparatus comprising: The substrate processing apparatus according to claim 1, wherein
The second encoder head, the third encoder head, and the first encoder head are disposed in this order from the upstream side with respect to the circumferential movement direction of the scale graduation accompanying the rotation of the rotary drum,
The first reading value Cm1, the second reading value Cm4, and the third reading value Cm5 are set to have a relationship of Cm1 <Cm5 <Cm4.
Substrate processing equipment. The substrate processing apparatus according to claim 2,
The constant angle α is set to α <θs with respect to the angle θs in the circumferential direction between the second direction and the third direction.
Substrate processing equipment. The substrate processing apparatus according to claim 3, wherein
The angle θs is set within 45 degrees,
The constant angle α is set to any value other than a divisor of 360 degrees, a value to be a prime number with respect to 360 degrees, or a value in which a value of 360 degrees / α is divisible by 1 to 4 decimal places. ,
Substrate processing equipment. The substrate processing apparatus according to any one of claims 1 to 4, wherein
The first orientation in which the first encoder head is disposed is set to be the same as the orientation in the circumferential direction of the specific position on which the processing unit performs processing,
When processing the sheet substrate by the processing unit, a value obtained by correcting the first reading value by the first encoder head based on the error information stored in the storage unit is the value of the sheet substrate. A substrate processing apparatus, further comprising: a correction unit that outputs a conveyance position or a conveyance amount in a long direction. The substrate processing apparatus according to claim 1 or 2, wherein
The scale graduation is fixed coaxially with the center line to at least one end of the rotary drum in a direction in which the center line extends, and is engraved on the outer peripheral portion of a scale disc that rotates with the rotary drum.
Substrate processing equipment. The substrate processing apparatus according to claim 6, wherein
In order to fix the scale disc to the end of the rotary drum, a plurality of fastening members are provided at predetermined mounting angles β along the circumferential direction of the scale disc,
The attachment angle β, the constant angle α, and the angle θs are set to a relationship of α <β <θs.
Substrate processing equipment. The substrate processing apparatus according to any one of claims 2 to 4, wherein
The scale graduation includes an origin mark provided at one of the entire circumferences,
A first counter which outputs the first read value Cm1 and which resets the first read value Cm1 to zero at the moment when the first encoder head detects the origin mark;
A second counter which outputs the second read value Cm4 and which resets the second read value Cm4 to zero at the moment when the second encoder head detects the origin mark;
And a third counter configured to output the third read value Cm5 and to zero reset the third read value Cm5 at the moment when the third encoder head detects the origin mark.
Substrate processing equipment. The substrate processing apparatus according to claim 8, wherein
Assuming that the maximum count value counted by each of the three counters during one rotation of the scale is Cmf,
When the origin mark is between the reading position of the second encoder head and the reading position of the third encoder head, the maximum count value Cmf is used as the second reading value Cm4 output by the second counter. Using the added count value Cm4 ′, the measurement value ΔMs is calculated by ΔMs = (Cm1 + Cm4 ′) / 2−Cm5,
When the origin mark is between the reading position of the third encoder head and the reading position of the first encoder head, the maximum count value Cmf is used as the third reading value Cm5 output by the third counter. The measurement value ΔMs is calculated by ΔMs = (Cm1 + Cm4 ′) / 2-Cm5 ′ using the added count value Cm5 ′ and the count value Cm4 ′.
Substrate processing equipment.

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