JP2006330534A - Reference index plate, method for adjusting reference index plate, exposing device and method for manufacturing micro device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reference index plate with which cost increase and lowering of a yield are suppressed, and which is used for a large sized exposing device. <P>SOLUTION: The reference index plate 29 is used for the exposing device which exposes a mask pattern on a photosensitive substrate via a projection optical system and is made to be a reference of the pattern to be projected or an image projected via the projection optical system, and is equipped with a base plate 32, and a plurality of reference plates 32a-32e which are attached on the base plate 32 and which have reference marks 34a-34l formed thereon. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a reference index plate used in an exposure apparatus for manufacturing a microdevice such as a flat panel display element such as a liquid crystal display element in a lithography process, a method for adjusting the reference index plate, and an exposure including the reference index plate The present invention relates to an apparatus and a microdevice manufacturing method using the exposure apparatus.

  A flat panel display element such as a liquid crystal display device is manufactured by a photolithography technique in which a pattern formed on a mask is transferred onto a photosensitive substrate. In this photolithography process, for example, when manufacturing a liquid crystal display device, a large glass substrate is used as a photosensitive substrate, and a mask stage on which a mask is placed and a substrate stage on which the photosensitive substrate is placed are projected into an optical system. In contrast, a scanning type exposure apparatus is used in which a mask pattern is continuously transferred onto a glass substrate through a projection optical system while being synchronously scanned.

  If the exposure process is continued, the optical characteristics (scaling, shift, rotation, etc.) of the projection optical system will change over time due to the irradiation heat of the exposure light, the pressure change in the installation space, etc. By performing calibration for adjusting optical characteristics using a correction mechanism such as a mechanism for driving some optical elements (lenses), the accuracy of the optical characteristics of the projection optical system is kept within a certain range. In a multi-lens scan type exposure apparatus having a projection optical system composed of a plurality of projection optical units, first, a mark formed on a mask and a reference index plate (reference member) provided on a substrate stage The relative position of the mark formed in the is detected. Based on the detection result, the positional deviation of the mask pattern formed on the photosensitive substrate via each projection optical unit is detected, and the positional deviation detected by adjusting the optical characteristics of each projection optical unit is detected. Calibration processing for correction is performed (see, for example, Patent Document 1).

JP 2004-172471 A

  By the way, with the recent increase in the size of the mask and the photosensitive substrate, the exposure apparatus main body has also increased in size, and the reference index plate used for detecting the relative position of the projection image formed by each projection optical unit has also increased in size. ing. Further, in order to maintain the accuracy of the optical characteristics of the projection optical system, it is necessary to manufacture the reference indicator plate with high accuracy. However, it is expensive to manufacture a large reference indicator plate made of quartz with high accuracy. And the yield decreases.

  An object of the present invention is to provide a reference index plate used in a large exposure apparatus capable of suppressing an increase in cost and a decrease in yield, a method for adjusting the reference index plate, an exposure apparatus including the reference index plate, and the exposure apparatus. It is providing the manufacturing method of the microdevice using this.

  The reference index plate of the present invention is used in an exposure apparatus that exposes a mask pattern onto a photosensitive substrate through a projection optical system, and a reference of a pattern projected through the projection optical system or a projected image is used. A reference index plate comprising: a base plate; and a plurality of reference plates attached on the base plate and formed with reference marks.

  According to the reference indicator plate of the present invention, since the plurality of reference plates on which the reference marks are formed are provided, one reference plate is manufactured with the cost and yield necessary for manufacturing the plurality of reference plates. Therefore, when compared with the cost and yield required for this purpose, the cost for manufacturing the reference plate can be suppressed, and a decrease in yield can be suppressed.

  According to another aspect of the present invention, there is provided a reference index plate adjustment method comprising: a mask stage on which a mask is placed; and a substrate stage on which a photosensitive substrate is placed on a projection optical system that projects the mask pattern onto the photosensitive substrate. A method of adjusting a reference index plate used in an exposure apparatus that exposes a pattern of the mask onto the photosensitive substrate by relatively moving the mask, and a plurality of reference plates on which reference marks are formed. A reference plate installation step of installing each of the reference marks on a base plate provided with a plurality of mark measurement systems for measuring the reference marks, and the reference marks corresponding to each of the plurality of mark measurement systems, A reference mark measurement process measured by each of the plurality of mark measurement systems, and a measurement result measured by the reference mark measurement process. An optical property adjustment step for adjusting optical properties with respect to a reference mark; a base plate installation step for installing the base plate including the plurality of mark measurement systems adjusted in the optical property adjustment step on the substrate stage; and A position adjustment step of adjusting the position of the base plate installed in the base plate installation step with respect to the substrate stage.

  According to the method for adjusting the reference index plate of the present invention, the optical characteristics of each mark measurement system with respect to the reference mark and the position of the base plate with respect to the substrate stage are adjusted, so that the displacement of each reference plate can be prevented. . Therefore, it is possible to measure the reference mark with the same accuracy as when the reference mark is measured using the reference index plate having only one reference plate.

  The exposure apparatus of the present invention includes a mask stage for placing a mask, a substrate stage for placing a photosensitive substrate, a projection optical system for projecting a pattern image of the mask onto the photosensitive substrate, and the substrate. A plurality of reference plates provided on a base plate attached to the stage and formed with reference marks, and a reference mark provided on a different reference plate among the reference marks provided on the plurality of reference plates Are positioned so as to correspond to the projection area projected by the projection optical system.

  According to the exposure apparatus of the present invention, since at least two of the reference marks formed on the plurality of reference plates provided on the reference index plate are positioned so as to correspond to the projection area, one reference plate The reference mark can be measured with the same accuracy as when the reference mark is measured using the reference indicator plate having only the reference mark. Therefore, the mask pattern can be exposed to an appropriate position on the photosensitive substrate with high accuracy. In addition, since the reference indicator plate having a plurality of reference plates can be manufactured at a lower cost than the reference indicator plate having only one reference plate, the manufacturing cost of the exposure apparatus main body can be suppressed.

  The microdevice manufacturing method of the present invention is a microdevice manufacturing method using the exposure apparatus of the present invention, in which an exposure process of exposing a mask pattern onto a photosensitive substrate and the exposure process are performed. And a developing step for developing the photosensitive substrate.

  According to the microdevice manufacturing method of the present invention, since exposure is performed by an exposure apparatus having a reference index plate having a plurality of reference plates on which reference marks are formed, the mask pattern is placed at an appropriate position on the photosensitive substrate. In addition, high-precision exposure can be performed, and a good microdevice can be obtained.

  According to the reference indicator plate of the present invention, since the plurality of reference plates on which the reference marks are formed are provided, the cost and yield required for manufacturing the plurality of reference plates can be reduced with one large reference plate. When compared with the cost and yield required for manufacturing, the cost for manufacturing the reference plate can be suppressed, and a decrease in yield can be suppressed.

  Further, according to the adjustment method of the reference index plate of the present invention, the optical characteristics of each mark measurement system with respect to the reference mark and the position of the base plate with respect to the substrate stage are adjusted, so that the displacement of each reference plate is prevented. Can do. Therefore, it is possible to measure the reference mark with the same accuracy as when the reference mark is measured using a reference indicator plate having only one large reference plate.

  Further, according to the exposure apparatus of the present invention, since at least two of the reference marks formed on the plurality of reference plates provided on the reference index plate are positioned so as to correspond to the projection area, one exposure mark is provided. The reference mark can be measured with the same accuracy as when the reference mark is measured using a reference indicator plate having only a large reference plate. Therefore, the mask pattern can be exposed to an appropriate position on the photosensitive substrate with high accuracy. In addition, since the reference indicator plate having a plurality of reference plates can be manufactured at a lower cost than the reference indicator plate having only one large reference plate, the manufacturing cost of the exposure apparatus main body can be suppressed.

  Further, according to the microdevice manufacturing method of the present invention, since the exposure is performed by the exposure apparatus including the reference index plate having the plurality of reference plates on which the reference marks are formed, the mask pattern is appropriately set on the photosensitive substrate. It is possible to perform exposure at a high position with high accuracy and to obtain a good micro device.

  An exposure apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an outline of an exposure apparatus according to this embodiment, and FIG. 2 is a schematic block diagram. As shown in FIGS. 1 and 2, the exposure apparatus EX includes a mask stage MST for placing a mask M on which a pattern is formed and a substrate stage PST for placing a photosensitive substrate P having an outer diameter larger than 500 mm. And an illumination optical system IL that illuminates the mask M with the exposure light EL, a projection optical system PL that projects the pattern of the mask M illuminated with the exposure light EL onto the photosensitive substrate P, and a control that controls the exposure process. And a device CONT. Here, the outer diameter of the photosensitive substrate P indicates one side of the photosensitive substrate P or a diagonal line of the photosensitive substrate P.

  In this embodiment, the projection optical system PL has a plurality (11 in this embodiment) of projection optical units PLa to PLk that divide and project a plurality of projection regions. In addition, the illumination optical system IL has a plurality (11 in this embodiment) of illumination optical units (not shown) corresponding to the projection optical units PLa to PLk.

  The exposure apparatus EX is a so-called scanning exposure apparatus that performs exposure by scanning a mask M (mask stage MST) and a photosensitive substrate P (substrate stage PST) in a predetermined direction relative to the projection optical system PL. This is a multi-lens scan type exposure apparatus. In the following description, the optical axis direction of the projection optical system PL is the Z direction, the direction perpendicular to the Z direction is the synchronous movement direction of the mask M and the photosensitive substrate P, and the Z direction is orthogonal to the X direction. Let the direction be the Y direction. Also, the respective directions around the X axis, Y axis, and Z axis are θX, θY, and θZ.

  Although not shown, the illumination optical system IL includes a light source, a light guide that once collects the light emitted from the light source, and then distributes and emits the light evenly, and a light flux having a uniform illuminance distribution. An optical integrator that converts the exposure light into (exposure light), a blind that has an opening for shaping the exposure light from the optical integrator into a slit shape, and a condenser lens that forms an image of the exposure light that has passed through the blind on the mask M are provided. The exposure light from the condenser lens illuminates the mask M with a plurality of slit-shaped illumination areas.

  FIG. 3 is a diagram showing the configuration of the mask M. As shown in FIG. As shown in FIG. 3, mark forming regions 27 and 28 having a plurality of marks are provided on both sides (± X side) of the mask M in the scanning direction. In the mark forming region 27 on the −X side, a plurality of marks 30 (30a to 30l) arranged at predetermined intervals in the Y direction are formed. In the mark formation region 28 on the + X side, a plurality of marks 31 (31a to 31l) arranged at predetermined intervals in the Y direction are formed. The marks 30 and 31 formed on the mark forming regions 27 and 28 are used for calibration for adjusting the optical characteristics of the projection optical system PL.

  The mask stage MST on which the mask M is placed is configured to be movable, and has a long stroke in the X direction (predetermined direction) and a predetermined distance in the Y direction orthogonal to the scanning direction to perform one-dimensional scanning exposure. Stroke. As shown in FIG. 2, a mask stage driving unit (scanning mechanism) MSTD is connected to the mask stage MST. The mask stage MST moves in the X direction and the Y direction by driving the mask stage driving unit MSTD. The mask stage drive unit MSTD is controlled by the control device CONT.

  As shown in FIG. 1, the exposure apparatus EX includes an X laser interferometer 1x that detects the position of the mask stage MST on which the mask M is placed in the X direction, and a Y laser interference that detects the position of the mask stage MST in the Y direction. 1y in total. An X moving mirror 2x extending in the Y direction is provided at an end on the −X side of the mask stage MST, and Y extending in the X direction so as to be orthogonal to the X moving mirror 2x is provided at an end on the −Y side. A movable mirror 2y is provided. An X laser interferometer 1x is disposed opposite to the X movable mirror 2x, and a Y laser interferometer 1y is disposed opposite to the Y movable mirror 2y. The X laser interferometer 1x detects the distance from the X moving mirror 2x by irradiating the X moving mirror 2x with laser light. The Y laser interferometer 1y irradiates the Y moving mirror 2y with laser light and detects the distance from the Y moving mirror 2y. The detection results of the laser interferometers 1x and 1y are output to the control device CONT. The control device CONT sets the mask stage MST to a desired position (attitude) by controlling the mask stage drive unit MSTD based on the detection results of the laser interferometers 1x and 1y.

  The exposure light EL that has passed through the mask M is incident on each of the projection optical units PLa to PLk. The projection optical units PLa to PLk project and expose a pattern image existing in the illumination area of the mask M onto the photosensitive substrate P, and are provided corresponding to each illumination optical unit. As shown in FIG. 1, among the plurality of projection optical units PLa to PLk, the projection optical units PLa, PLc, PLe, PLg, PLi, and PLk are arranged in a direction orthogonal to the scanning direction (direction intersecting a predetermined direction). The projection optical units PLb, PLd, PLf, PLh, and PLj are arranged in a row in a direction orthogonal to the scanning direction (a direction intersecting with a predetermined direction). The projection optical units PLa, PLc, PLe, PLg, PLi, and PLk (hereinafter referred to as a first projection optical unit group) and the projection optical units PLb, PLd, PLf, PLh, and PLj (referred to as a second projection optical unit group). Are arranged in a staggered pattern. Each of these projection optical units PLa to PLk passes a plurality of exposure lights EL emitted from the illumination optical unit and passed through the mask M, and projects a pattern image of the mask M onto the photosensitive substrate P.

  As shown in FIG. 2, the projection optical unit PLj includes a shift adjustment mechanism 5, two sets of catadioptric optical systems 10, 20, an image plane adjustment mechanism 6, a field stop (not shown), and a scaling adjustment mechanism 7. The other projection optical units PLa to PLi, PLk have the same configuration as the projection optical unit PLj.

  The light beam that has passed through the mask M enters the shift adjustment mechanism 5. The shift adjustment mechanism 5 includes a parallel flat glass plate 5A provided so as to be rotatable around the Y axis, and a parallel flat glass plate 5B provided so as to be rotatable around the X axis. The parallel flat glass plate 5A is rotated around the Y axis by a driving device 5Ad such as a motor, and the parallel flat glass plate 5B is rotated around the X axis by a driving device 5Bd such as a motor. When the plane parallel glass plate 5A rotates around the Y axis, the pattern image of the mask M on the photosensitive substrate P shifts in the X direction, and when the plane parallel glass plate 5B rotates around the X axis, the photosensitive substrate P. The pattern image of the mask M above is shifted in the Y direction. The drive devices 5Ad and 5Bd are controlled by the control device CONT.

  The light beam that has passed through the shift adjustment mechanism 5 enters the first set of catadioptric optical system 10. The catadioptric optical system 10 forms an intermediate image of the pattern of the mask M, and includes a right-angle prism 11, a lens 12, and a concave mirror 13. The right-angle prism 11 is configured to be rotatable around the Z axis, and is rotated around the Z axis by a driving device 11d such as a motor. As the right-angle prism 11 rotates around the Z axis, the pattern image of the mask M on the photosensitive substrate P rotates around the Z axis. That is, the right-angle prism 11 has a function as a rotation adjustment mechanism. The drive device 11d is controlled by the control device CONT. A field stop (not shown) is disposed at a position where an intermediate image of the catadioptric optical system 10 is formed. The field stop has a trapezoidal opening and forms a projection region projected onto the photosensitive substrate P. The light beam that has passed through the aperture of the field stop is incident on the image plane adjustment mechanism 6.

  The image plane adjustment mechanism 6 is installed at or near the position where the intermediate image of the catadioptric optical system 10 is formed by adjusting the imaging position of the projection optical system PLj and the inclination of the image plane. The image plane adjustment mechanism 6 is provided with respect to the first optical member 6A, the second optical member 6B, the first optical member 6A, and the second optical member 6B. Drive devices 6Ad and 6Bd for moving the first optical member 6A are provided. The first optical member 6A and the second optical member 6B are formed in a wedge shape, and constitute a pair of wedge-shaped optical members. The driving devices 6Ad and 6Bd move the first optical member 6A so as to slide in the X direction relative to the second optical member 6B, and the image plane position of the projection optical system PLj moves in the Z direction. In addition, the first optical member 6A is rotated in the θZ direction with respect to the second optical member 6B by the driving devices 6Ad and 6Bd, and the image plane of the projection optical system PLj is inclined. The drive devices 6Ad and 6Bd are controlled by the control device CONT. The light beam that has passed through the image plane adjustment mechanism 6 enters the second set of catadioptric optical system 20.

  The catadioptric optical system 20 has the same configuration as the catadioptric optical system 10 and forms a pattern image on the photosensitive substrate P. The light beam that has passed through the catadioptric optical system 20 passes through the scaling adjustment mechanism 7 and forms an image of the pattern of the mask M on the photosensitive substrate P at an erecting equal magnification. The scaling adjustment mechanism 7 includes a lens and a driving device 7d. The magnification (scaling) of the pattern image of the mask M can be adjusted by moving the lens in the Z direction by the driving device 7d. The driving device 7d is controlled by the control device CONT.

  The substrate stage PST has a long stroke in the X direction (predetermined direction) and a long stroke for stepping in the Y direction perpendicular to the scanning direction in order to perform one-dimensional scanning exposure. As shown in FIG. 2, a substrate stage driving unit (scanning mechanism) PSTD is connected to the substrate stage PST. The substrate stage PST is moved in the X direction, the Y direction, the Z direction, the θX, θY, and θZ directions by driving the substrate stage driving unit PSTD. The substrate stage drive unit PSTD is controlled by the control device CONT.

  As shown in FIG. 1, the exposure apparatus EX includes an X laser interferometer 3x that detects the position of the substrate stage PST in the X direction, and a Y laser interferometer 3y that detects the position of the substrate stage PST in the Y direction. Yes. An X moving mirror 4x extending in the Y direction is provided at the −X side edge of the substrate stage PST, and a Y extending in the X direction so as to be orthogonal to the X moving mirror 4x is provided at the −Y side edge. A movable mirror 4y is provided. An X laser interferometer 3x is arranged to face the X movable mirror 4x, and a Y laser interferometer 3y is arranged to face the Y movable mirror 4y. The X laser interferometer 3x irradiates the X moving mirror 4x with laser light and detects the distance from the X moving mirror 4x. The Y laser interferometer 3y irradiates the Y moving mirror 4y with laser light and detects the distance from the Y moving mirror 4y. The detection results of the laser interferometers 3x and 3y are output to the control device CONT. The control device CONT sets the substrate stage PST to a desired position (attitude) by controlling the substrate stage drive unit PSTD based on the detection results of the laser interferometers 3x and 3y.

  A reference indicator plate 29 extending along the Y direction is provided at a predetermined position on the −X side of the substrate stage PST. The reference indicator plate 29 is used when the projection optical units PLa to PLk are calibrated. 4 and 5 are diagrams showing the configuration of the reference indicator plate 29. FIG. As shown in the plan view of FIG. 4 and the side view of FIG. 5, the reference indicator plate 29 includes a base plate 32 made of a low expansion member such as super invar, ceramic, zero dewar, etc. having an expansion rate of 2 ppm or less. Yes. Therefore, when the reference indicator plate 29 is irradiated with light, it is caused by heat generated by the mark measurement by the AIS light receiving system 60 or heat generated during exposure of the photosensitive substrate P placed on the substrate stage PST. Without being affected by the base plate 32, the base plate 32 functions well as a reference index plate 29 as a reference at the time of calibration of the projection optical units PLa to PLk.

  The reference indicator plate 29 includes a plurality (five in this embodiment) of reference plates 32a to 32e attached on the base plate 32. The reference plates 32a to 32e are respectively fixed on a plurality of reference base plates 33a to 33e fixed on the base plate 32. The reference plate is a case where the projection optical units are arranged in a plurality of rows as rows arranged in the Y direction, and the number of the projection optical units arranged in the row having the largest number of projection optical units among the plurality of rows. It is desirable that the number be one or more less. For example, in this embodiment, as shown in FIG. 6A, the number of first projection optical unit groups in a plurality of rows (2 rows) is 6, and there are 5 spaces between the projection optical units. Become. In order to provide the reference marks on both sides of each projection optical unit, it is preferable to dispose a reference plate so as to be positioned between adjacent projection optical units as shown in FIG. Also, as shown in FIG. 6B, six reference plates may be arranged in accordance with the projection area formed by each projection optical unit. In other words, if the projection areas of a plurality of (three or more) projection optical units are covered, the size of each reference plate becomes too large, and the two reference marks provided for each projection optical unit are individually set as individual reference plates. When it is provided, the influence of the attachment error tends to appear on each reference mark, and the attachment time and adjustment time increase.

  Further, as shown in FIG. 6C, three reference plates may be provided. In the actual product, since it is necessary to enlarge the central reference plate, the reference indicator plate (FIG. 6A) according to this embodiment is arranged. That is, in this embodiment, the number of projection optical units in the first projection optical unit group is larger than the number of projection optical units in the second projection optical unit group, and the number is six, and the reference plates 32a to 32e. Is five.

  In addition, the reference plates 32a to 32e are spaced in the Y direction between adjacent projection optical units (for example, the projection plate 32a and the interval between the reference plates 32b and the interval between the reference plates 32b and 32c). The distance between the optical units PLa and PLb, the distance between PLb and PLc) is approximately equal. As shown in FIG. 2, the position (height) in the Z direction of the surface of the reference plates 32a to 32e and the position (height) in the Z direction of the surface of the photosensitive substrate P are configured to substantially coincide with each other. Yes.

  On the reference plate 32a, reference marks 34a to 34c serving as a reference for an image projected through the projection optical system PL are formed. Similarly, reference marks 34d and 34e are formed on the reference plate 32b, reference marks 34f and 34g are formed on the reference plate 32c, reference marks 34h and 34i are formed on the reference plate 32d, and reference marks 34j to 34l are formed on the reference plate 32e. ing. Further, at least two reference marks formed on different reference plates are positioned so as to correspond to the projection areas projected by the different projection optical units. By providing a reference mark for the projection area of the projection optical unit, by measuring the relative positional relationship between the mark provided on the mask side and the mark provided on the reference indicator plate via the projection optical system, It is possible to measure the image rotation shift of the projection optical unit and to obtain the relative positional relationship between the marks. On the reference indicator plate 29, alignment marks 36a to 36f used for alignment of the reference indicator plate 29 are formed.

  Also, below the reference indicator plate 29 (reference mark 341), an AIS light receiving system (mark) that measures the reference mark 341 by receiving light that has passed through the reference mark 341 so as to be embedded in the substrate stage PST. (Measurement system) 60 is provided. Similarly, below each of the reference marks 34a to 34k, a plurality of AIS light receiving systems (not shown, hereinafter referred to as other AIS light receiving systems) corresponding to the reference marks so as to be embedded in the substrate stage. ) Is provided. The AIS light receiving system 60 includes a lens system 61 and an image sensor 62 that is a CCD that receives light via the lens system 61. The measurement result by the AIS light receiving system 60 is output to the control device CONT. The other AIS light receiving systems have the same configuration as that of the AIS light receiving system 60, and the measurement results of the other AIS light receiving systems are output to the control device CONT.

  When calibrating the first projection optical unit group, the control device CONT outputs a control signal to the mask stage driving device MSTD, and moves the mask stage MST by driving the mask stage driving device MSTD. Thus, the mark forming region 27 or 28 is disposed at a position where light is irradiated through the illumination optical system IL. Similarly, a control signal is output to the substrate stage driving device PSTD, the substrate stage PST is moved by driving the substrate stage driving device PSTD, and the reference indicator plate 29 is moved through the first projection optical unit group. It arrange | positions in the position irradiated with the light.

  The control device CONT illuminates the mark 30 or 31 formed in the mask formation region 27 or 28 with the illumination optical system IL. The light that has passed through the mark 30 or 31 reaches the reference plates 32a to 32e of the reference indicator plate 29 via the first projection optical unit group. The light that has passed through the reference marks 34 a to 34 l formed on the reference plates 32 a to 32 e passes through the lens 61 of the AIS light receiving system 60 and is guided to the image sensor 62. The measurement result obtained by the image sensor 62 is output to the control device CONT.

  The control device CONT, based on the measurement result by the image sensor 62, that is, the relative position (position shift amount) between the mark 30 or 31 and the reference marks 34a to 34l, each projection optical unit PLa, Each optical characteristic (shift, scaling, rotation) of PLc, PLe, PLg, PLi, and PLk is measured, and a correction amount is calculated.

  The control device CONT controls at least one of the drive devices 5Ad, 5Bd, the drive device 11d, and the drive device 7d of each of the projection optical units PLa, PLc, PLe, PLg, PLi, and PLk based on the calculated correction amount. By outputting a signal and driving at least one of the drive devices 5Ad and 5Bd, the drive devices 6Ad and 6Bd, the drive device 11d, and the drive device 7d, the shift adjustment mechanism 5, the image plane adjustment mechanism 6, the right-angle prism 11, and the scaling. At least one of the optical members constituting the adjustment mechanism 7 is rotated by a predetermined amount to adjust the optical characteristics of the first projection optical unit group.

  When the second projection optical unit group is calibrated after the calibration of the first projection optical unit group, the control device CONT outputs a control signal to the substrate stage driving device PSTD, and the substrate stage driving device PSTD. Is moved to move the substrate stage PST in the X direction (scanning direction), and the reference indicator plate 29 is arranged at a position where light is irradiated through the second projection optical unit group. At the same time, by driving the substrate stage driving device PSTD, the substrate stage PST corresponds to the interval between the projection optical units adjacent in the Y direction (for example, the interval in the Y direction between the projection optical units PLa and PLb and PLb and PLc). Shift the amount you want. By shifting, the reference mark 34a located at the end in the Y direction of the reference indicator plate 29 is measured by light via the projection optical unit PLa and the projection optical unit PLb located at the end in the Y direction. Become.

  The control device CONT illuminates the mark 30 or 31 formed in the mask formation region 27 or 28 with the illumination optical system IL. The light that has passed through the mark 30 or 31 reaches the reference plates 32a to 32e of the reference indicator plate 29 via the second projection optical unit group. The light that has passed through the reference marks 34 a to 34 l formed on the reference plates 32 a to 32 e passes through the lens 61 of the AIS light receiving system 60 and is guided to the image sensor 62. The measurement result obtained by the image sensor 62 is output to the control device CONT.

  The control device CONT, based on the measurement result by the image sensor 62, that is, the relative position (position shift amount) between the mark 30 or 31 and the reference marks 34a to 34l, each projection optical unit PLb, which constitutes the second projection optical unit group, Each optical characteristic (shift, scaling, rotation) of PLd, PLf, PLh, and PLj is measured, a correction amount is calculated, and the optical characteristics of the second projection optical unit group are adjusted.

  Further, the control device CONT measures whether or not the positional deviations of the plurality of reference plates 32a to 32e of the reference indicator plate 29 installed on the substrate stage PST have occurred every predetermined period, and the positional deviation has occurred. If so, make adjustments. Specifically, alignment marks 36a to 36f formed on the reference indicator plate 29 by an alignment system (not shown) arranged between the first projection optical unit group and the second projection optical unit group are used. Then, based on the detection result, the amount of displacement of the reference plates 32a to 32e is detected, and the displacement is corrected.

  Next, a method for adjusting the reference indicator plate 29 according to this embodiment will be described. When the reference indicator plate 29 is installed on the substrate stage PST, the arrangement of the reference plates 32a to 32e on which the reference marks are formed is adjusted, and the AIS provided corresponding to each of the reference marks 34a to 34l. It is necessary to accurately adjust the optical characteristics of the light receiving system and arrange the reference plates 32a to 32e. FIG. 7 is a flowchart for explaining a method of adjusting the reference indicator plate 29 according to this embodiment.

  First, using a micrometer head or the like, the reference plate 32a is installed at an accurate position on the reference base plate 33a. Similarly, each of the reference plates 32b to 32e is accurately installed at each predetermined position on the reference base plates 33b to 33e (step S10). Next, a plurality of AIS light receiving systems are installed on the reference base plate 33a so as to correspond to the respective reference marks 34a to 34l. Similarly, an AIS light receiving system is installed on the reference base plates 33b to 33e so as to correspond to the reference marks 34a to 34l formed on the reference plates 32b to 32e (step S11).

  Next, the reference base plates 33a to 33e on which the reference plates 32a to 32e are installed are accurately installed at predetermined positions on the base plate 32 (step S12, reference plate installation step). Next, the reference marks 34a to 34l corresponding to each of the plurality of AIS light receiving systems are measured by each of the plurality of AIS light receiving systems (step S13, reference mark measuring step).

  Next, based on the measurement result measured in step S13, the optical characteristics for each of the reference marks 34a to 341 of the plurality of AIS light receiving systems are adjusted (step S14, optical characteristics adjusting step). Specifically, the focus position with respect to the reference mark, the shift in the scanning direction (X direction) when the reference indicator plate 29 is installed in the exposure apparatus EX, the shift in the direction orthogonal to the scanning direction (Y direction), the θZ direction Make adjustments such as rotation.

  Next, relative arrangement adjustment between the plurality of AIS light receiving systems adjusted in step S14 is performed (step S15). Specifically, the relative position between the AIS light receiving systems is detected using a dedicated tool equipped with a CCD camera or the like adjusted with coordinate-managed tool glass, and the positional deviation is detected based on the detection result. Correction is performed, and relative arrangement adjustment between the AIS light receiving systems is performed.

  Next, the base plate 32 is accurately placed at a predetermined position on the substrate stage PST (step S16, base plate placement step). Next, the position of the base plate 32 installed in step S16 is adjusted with respect to the substrate stage PST (step S17, position adjustment process). Specifically, by measuring an alignment mark formed on the reference index plate 29 by an alignment system (not shown) arranged between the first projection optical unit group and the second projection optical unit group. Then, the reference index plate 29 is adjusted in the θZ direction with respect to the projection optical system PL.

  According to the reference indicator plate according to this embodiment, since a plurality of reference plates on which reference marks are formed are provided, the cost and yield required for manufacturing the plurality of reference plates are reduced to one reference plate. Compared with the cost and yield required for manufacturing the reference plate, the cost for manufacturing the reference plate can be suppressed, and the decrease in the yield can be suppressed.

  In addition, according to the projection exposure apparatus according to this embodiment, at least two reference marks formed on different reference plates are positioned so as to correspond to the projection areas projected by different projection optical units. The reference mark can be measured with the same accuracy as when the reference mark is measured using a reference indicator plate having only one reference plate. Therefore, the mask pattern can be exposed to an appropriate position on the photosensitive substrate with high accuracy. In addition, since the reference indicator plate having a plurality of reference plates can be manufactured at a lower cost than the reference indicator plate having only one reference plate, the manufacturing cost of the exposure apparatus main body can be suppressed.

  Further, according to the method of adjusting the reference indicator plate according to this embodiment, the optical characteristics of each AIS light receiving system with respect to the reference mark and the position of the base plate with respect to the substrate stage are adjusted. Can be prevented. Therefore, it is possible to measure the reference mark with the same accuracy as when the reference mark is measured using the reference index plate having only one reference plate.

  Note that the projection exposure apparatus according to this embodiment includes a reference index plate having five reference plates. However, a reference index plate having at least three reference plates may be provided.

  In this embodiment, the number of projection optical units in the first projection optical unit group is six, and the number of reference plates provided on the reference index plate is five. Since the number of projection optical units in the group is five, the number of reference plates may be at least four. That is, when the number of projection optical units in any one of the plurality of rows is n, the number of the plurality of reference plates may be at least (n−1). Further, when the plurality of projection optical units are arranged in one row instead of the plurality of rows in the direction orthogonal to the scanning direction, and the number of projection optical units is n, the number of the plurality of reference plates is at least (n−1). It is desirable to be individual.

  In this embodiment, a so-called multi-lens scanning exposure apparatus has been described as an example. However, the present invention can also be applied to a scanning exposure apparatus that performs exposure using one projection optical system. In this case, at least two of the reference marks provided on different reference plates among the reference marks provided on the plurality of reference plates provided in the reference indicator plate are positioned in the projection area projected by the projection optical system. . Using the reference index plate according to this embodiment, it is possible to measure the positional deviation of the projection region with respect to the photosensitive substrate when the pattern is not projected to an appropriate position on the photosensitive substrate by the projection optical system, Based on the measurement result, the optical characteristics of the projection optical system can be adjusted.

  In this embodiment, two rows of a plurality of projection optical units arranged in a direction orthogonal to the scanning direction are arranged, but three or more rows may be arranged.

  In the exposure apparatus according to the above-described embodiment, the reticle (mask) is illuminated by the illumination optical system, and the transfer pattern formed on the mask is exposed to the photosensitive substrate (plate) using the projection optical system. Microdevices (semiconductor elements, imaging elements, liquid crystal display elements, thin film magnetic heads, etc.) can be manufactured. FIG. 8 is a flowchart of an example of a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a plate or the like as a photosensitive substrate using the exposure apparatus according to the above-described embodiment. The description will be given with reference.

  First, in step S301 in FIG. 8, a metal film is deposited on one lot of plates. In the next step S302, a photoresist is applied on the metal film on the one lot of plates. Thereafter, in step S303, using the exposure apparatus according to the above-described embodiment, the pattern image on the mask is sequentially exposed and transferred to each shot area on the plate of one lot via the projection optical system. Thereafter, in step S304, the photoresist on the one lot of plates is developed, and in step S305, etching is performed on the one lot of plates using the resist pattern as a mask to obtain a pattern on the mask. A corresponding circuit pattern is formed in each shot area on the plate.

  Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the above-described microdevice manufacturing method, since exposure is performed using the exposure apparatus according to the above-described embodiment, a good microdevice can be obtained. In steps S301 to S305, a metal is vapor-deposited on the plate, a resist is applied on the metal film, and exposure, development and etching processes are performed. Prior to these processes, the process is performed on the plate. It is needless to say that after forming a silicon oxide film, a resist may be applied on the silicon oxide film, and steps such as exposure, development, and etching may be performed.

  In the exposure apparatus according to the above-described embodiment, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG. In FIG. 9, in the pattern formation step S401, a so-called photolithography process is performed in which the exposure pattern according to the above-described embodiment is used to transfer and expose a mask pattern onto a photosensitive substrate (such as a glass substrate coated with a resist). Is done. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step S402.

  Next, in the color filter forming step S402, a large number of groups of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three of R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning line direction. Then, after the color filter formation step S402, a cell assembly step S403 is executed. In the cell assembly step S403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step S401, the color filter obtained in the color filter formation step S402, and the like. In the cell assembly step S403, for example, liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern formation step S401 and the color filter obtained in the color filter formation step S402, and a liquid crystal panel (liquid crystal cell ).

  Thereafter, in a module assembly step S404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, since exposure is performed using the exposure apparatus according to the above-described embodiment, a good liquid crystal display element can be obtained.

1 is a schematic perspective view of an exposure apparatus according to an embodiment. 1 is a schematic block diagram of an exposure apparatus according to an embodiment. It is a figure which shows the structure of the mask concerning embodiment. It is a top view which shows the structure of the reference | standard index board concerning embodiment. It is a side view which shows the structure of the reference | standard index board concerning embodiment. It is a figure for demonstrating the positional relationship of the reference | standard parameter | index plate concerning embodiment, and a projection optical unit. It is a flowchart for demonstrating the adjustment method of the reference | standard index board concerning embodiment. It is a flowchart which shows the manufacturing method of the semiconductor device as a microdevice concerning embodiment of this invention. It is a flowchart which shows the manufacturing method of the liquid crystal display element as a microdevice concerning embodiment of this invention.

Explanation of symbols

  1x, 1y, 3x, 3y ... laser interferometer, 27, 28 ... mark formation region, 29 ... reference indicator plate, 32 ... base plate, 32a-32e ... reference plate, 33a-33e ... reference base plate, EX ... exposure apparatus , IL: illumination optical system, M: mask, MST: mask stage, PL: projection optical system, PLa to PLk: projection optical unit, P: photosensitive substrate, PST: substrate stage.

Claims (11)

A reference index plate used in an exposure apparatus that exposes a pattern of a mask onto a photosensitive substrate via a projection optical system, and serves as a reference for a pattern or projected image projected via the projection optical system,
A base plate,
A plurality of reference plates mounted on the base plate and formed with reference marks;
A reference indicator plate comprising: The mask stage on which the mask is placed and the substrate stage on which the photosensitive substrate is placed are scanned and moved relative to the projection optical system that projects the pattern of the mask onto the photosensitive substrate. A method for adjusting a reference indicator plate used in an exposure apparatus that exposes the photosensitive substrate on the photosensitive substrate,
A reference plate installation step of installing each of a plurality of reference plates on which a reference mark is formed on a base plate provided with a plurality of mark measurement systems for measuring the reference marks;
A reference mark measuring step for measuring the reference mark corresponding to each of the plurality of mark measurement systems by each of the plurality of mark measurement systems;
Based on the measurement result measured by the reference mark measurement step, an optical property adjustment step for adjusting the optical property for each of the reference marks of the plurality of mark measurement systems,
A base plate installation step of installing the base plate comprising the plurality of mark measurement systems adjusted by the optical characteristic adjustment step on the substrate stage;
A position adjustment step of adjusting the position of the base plate installed in the base plate installation step with respect to the substrate stage;
The adjustment method of the reference | standard parameter | index board characterized by including. A mask stage on which a mask is placed;
A substrate stage on which a photosensitive substrate is placed;
A projection optical system for projecting the pattern of the mask onto the photosensitive substrate;
A plurality of reference plates provided on a base plate attached to the substrate stage and formed with reference marks;
Of the reference marks provided on the plurality of reference plates, at least two of the reference marks provided on different reference plates are positioned so as to correspond to a projection area projected by the projection optical system. Exposure device.   4. The exposure apparatus according to claim 3, wherein the base plate is composed of a low expansion member.   The exposure apparatus according to claim 3 or 4, wherein the number of the plurality of reference plates is at least three or more. The projection optical system includes a plurality of projection optical units, and a plurality of exposure regions exposed by the plurality of projection optical units are formed on the photosensitive substrate,
The plurality of reference plates are arranged to correspond to the plurality of exposure regions,
6. The exposure apparatus according to claim 3, wherein an outer diameter of the photosensitive substrate is larger than 500 mm. The projection optical system comprises a plurality of projection optical units that divide and project a plurality of projection regions,
7. The number of the plurality of projection optical units is n, and the number of the plurality of reference plates is at least (n-1). The exposure apparatus described. The mask stage and the substrate stage have a scanning mechanism that scans in a predetermined direction relative to the projection optical system,
The projection optical system includes a plurality of projection optical units that divide and project a plurality of projection areas, and the plurality of projection optical units are arranged in a plurality of rows as rows arranged in a direction intersecting the predetermined direction. And
The number of the plurality of reference plates is at least (n-1) when n is the number of the plurality of projection optical units arranged in one of the plurality of rows. The exposure apparatus according to any one of claims 3 to 6.   When measuring each of the plurality of rows of the plurality of projection optical units with the reference indicator plate, the plurality of projection optical units in the direction intersecting the substrate stage in a direction intersecting the predetermined direction. The exposure apparatus according to claim 8, further comprising a control unit that performs measurement by shifting an amount corresponding to the interval.   10. The exposure according to claim 3, wherein an interval between the plurality of reference plates is substantially equal to an interval between adjacent projection optical units of the plurality of projection optical units. apparatus. A method of manufacturing a microdevice using the exposure apparatus according to any one of claims 3 to 10,
An exposure step of exposing the pattern of the mask onto the photosensitive substrate;
A developing step of developing the photosensitive substrate exposed by the exposing step;
A method for manufacturing a microdevice, comprising:

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