JP2008216554A - Temperature measuring device, scanning exposure device, exposure method and method for manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature measuring device capable of accurately measuring the temperature difference between a region where a pattern to be transferred is formed and a region where the pattern is not formed. <P>SOLUTION: The temperature measuring device 13 measures the temperature of an original plate M having pattern formation regions M1 to M5 where patterns to be transferred are formed; and the device includes first temperature measuring devices T1 to T5 to measure the temperature of at least one point in the pattern formation regions M1 to M5 and second temperature measuring devices t1 to t6 to measure the temperature of at least one point in non-pattern formation regions m1 to m6 where the pattern to be transferred is not formed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a temperature measuring apparatus used in an exposure apparatus or the like for manufacturing a micro device such as a flat panel display element such as a liquid crystal display element in a lithography process, a scanning exposure apparatus provided with the temperature measuring apparatus, and the scanning type The present invention relates to an exposure method using an exposure apparatus and a device manufacturing method using the exposure method.

  Projection exposure for projecting a mask (reticle, photomask, etc.) pattern onto a resist-coated plate (glass plate, semiconductor wafer, etc.) via a projection optical system when manufacturing a semiconductor element or a liquid crystal display element, etc. The device is in use. Conventionally, a projection exposure apparatus (stepper) that performs batch exposure of a reticle pattern on each shot area on a plate by the step-and-repeat method has been widely used. In recent years, instead of using one large projection optical system, a plurality of small projection optical units having the same magnification are arranged in a staggered manner in a direction orthogonal to the scanning direction, and each projection is performed while scanning the mask and the plate. A step-and-scan projection exposure apparatus has been proposed in which an optical unit exposes a mask pattern on a plate.

  In the above-described step-and-scan type projection exposure apparatus, an intermediate image is formed once by a catadioptric optical system comprising a reflecting prism, a concave mirror and each lens, and further masked by another stage catadioptric optical system. The upper pattern is exposed on the plate at the same size as an erect image.

In recent years, plates have become increasingly larger, and plates exceeding 2 m square have been used. Here, when exposure is performed on a large plate using the above-described step-and-scan type exposure apparatus, the projection optical unit has the same magnification, so that the mask is also enlarged. The cost of the mask also needs to maintain the flatness of the mask substrate, and becomes higher as the size increases. Further, in order to form a normal TFT portion, a mask for 4 to 5 layers is required, and a great cost is required. Accordingly, there has been proposed a projection exposure apparatus in which the mask size is reduced by setting the magnification of the projection optical system to be an enlargement magnification (see Patent Document 1).
JP-A-11-265848

  In the projection exposure apparatus provided with the projection optical system having the above-described magnification, a mask in which a region where a pattern is formed and a region where a pattern is not formed are alternately formed in a direction perpendicular to the scanning direction is provided. It is used. When a pattern is transferred using such a mask, the area where the pattern to be transferred is formed is illuminated by the illumination optical system, but the area where the pattern to be transferred is not formed is illuminated. Not illuminated by the optical system. Therefore, an area illuminated by the illumination optical system and an area not illuminated are present on the original, and a temperature difference occurs between the illuminated area and the unilluminated area. When pattern exposure is performed in a state where the original plate is anisotropically deformed due to a temperature difference, a reduction in joint accuracy of a joint area formed by overlapping a part of an image formed by each projection optical unit on the plate, a pattern As a result, the line width variation and the overlay accuracy of the overlay exposure of each layer are reduced.

  An object of the present invention is to provide a temperature measuring device capable of accurately measuring a temperature difference between a region where a pattern to be transferred is formed and a region where a pattern is not formed, and the temperature measuring device. A scanning exposure apparatus, an exposure method using the scanning exposure apparatus, and a device manufacturing method using the exposure method are provided.

  The temperature measuring device according to the present invention is a temperature measuring device (13) for measuring the temperature of an original (M) having pattern forming regions (M1 to M5) on which a pattern to be transferred is formed, and the pattern forming region A first temperature measuring device (T1 to T5) that measures the temperature of at least one point in (M1 to M5), and a temperature of at least one point in a non-pattern forming region (m1 to m6) where a pattern to be transferred is not formed It has the 2nd temperature measuring device (t1-t6) to measure, It is characterized by the above-mentioned.

  The temperature measuring device of the present invention is a temperature measuring device (13) having a predetermined pattern and measuring the temperature of the original (M) illuminated by the illumination optical system (IL), the illumination optical system. A first temperature measuring device (T1 to T5) that measures the temperature of at least one point in the illumination area (M1 to M5) on the original (M) illuminated by (IL), and the illumination optical system (IL). And a second temperature measuring device (t1 to t6) that measures the temperature of at least one point in the non-illuminated region (m1 to m6) on the original (M) that is not illuminated.

  The scanning exposure apparatus of the present invention has an enlargement magnification in which a pattern formed on an original (M) illuminated by an illumination optical system (IL) is arranged at a predetermined interval in a direction crossing the scanning direction. A scanning exposure apparatus that transfers onto an irradiated object (P) via a plurality of projection optical systems (PL1 to PL5), and is characterized by comprising the temperature measuring device (13) of the present invention.

  Further, the exposure method of the present invention has a plurality of magnifications having a pattern formed on the original (M) illuminated by the illumination optical system (IL) and arranged at predetermined intervals in a direction intersecting the scanning direction. An exposure method in which exposure is performed using a scanning exposure apparatus that transfers onto an object to be irradiated (P) via projection optical systems (PL1 to PL5), the illumination optical system (IL) on the original (M) ) And a non-illumination that is not illuminated by the illumination optical system (IL) on the original plate (M). Based on the measurement results of the second temperature measurement step (S11) for measuring at least one temperature in the region (m1 to m6), the first temperature measurement step (S10), and the second temperature measurement step (S11). , The plurality of projection optical systems (PL1 to PL ) For calculating the adjustment amount for the image forming state of the image formed by each of the above), and adjusting the image forming state based on the adjustment amount calculated by the calculating step (S12). And an adjusting step (S13) to be performed.

  Further, the device manufacturing method of the present invention includes an exposure step (S303) in which a pattern is exposed on a photosensitive substrate (P) using the exposure method of the present invention, and the photosensitive layer exposed by the exposure step (S303). And a developing step (S304) for developing the conductive substrate (P).

  According to the temperature measuring apparatus of the present invention, the first temperature measuring device that measures the temperature of at least one point in the pattern forming region and the second temperature measuring device that measures the temperature of at least one point in the non-pattern forming region are provided. Therefore, the temperature of the pattern formation region and the temperature of the non-pattern formation region can be accurately measured, and the temperature difference between the pattern formation region and the non-pattern formation region can be accurately detected. Therefore, it is possible to accurately detect the deformation amount due to the temperature change of the original plate.

  In addition, according to the temperature measuring apparatus of the present invention, the first temperature measuring device that measures the temperature of at least one point in the illumination area on the original plate illuminated by the illumination optical system, and the non-illuminated on the original plate that is not illuminated by the illumination optical system. And a second temperature measuring device that measures the temperature of at least one point in the illumination area, so that the temperature of the illumination area and the temperature of the non-illumination area can be accurately measured. A temperature difference can be accurately detected. Therefore, it is possible to accurately detect the deformation amount due to the temperature change of the original plate.

  Further, according to the scanning exposure apparatus of the present invention, since the temperature measuring apparatus of the present invention is provided, the illumination area on the original plate illuminated by the illumination optical system and the non-illumination area on the original plate not illuminated by the illumination optical system The amount of deformation due to a temperature change of the original plate can be accurately detected using the detection result. Therefore, by appropriately adjusting the image formation state of the projection optical system using the detection result, the exposure accuracy is reduced due to the deformation of the original, for example, a part of the image formed by a plurality of projection optical systems. It is possible to prevent a reduction in the joining accuracy of the joining region formed on the irradiated body, a variation in the line width of the pattern, a decline in the overlay accuracy of the overlay exposure of each layer, and the like.

  Further, according to the exposure method of the present invention, the image forming state is adjusted based on the adjustment amount of the image forming state calculated from the temperature measurement result of the illumination area and the non-illumination area, and therefore, the deformation of the original is a factor. Decrease in exposure accuracy, for example, decrease in splicing accuracy of spliced areas formed by overlapping a part of an image formed by a plurality of projection optical systems on the irradiated object, variation in pattern line width, and overlay exposure of each layer Thus, it is possible to prevent a decrease in overlay accuracy, and to perform good exposure.

  Moreover, according to the device manufacturing method of the present invention, since exposure is performed using the exposure method of the present invention, highly accurate exposure can be performed and a good device can be manufactured.

  Hereinafter, a scanning exposure apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a scanning exposure apparatus according to this embodiment. In this embodiment, the mask M illuminated by the illumination optical system IL including the light source while moving the mask (original plate) M and the plate (irradiated body, photosensitive substrate) P in the scanning direction (X direction). A plurality of projection optical units PL1 having a predetermined magnification (twice in this embodiment) in which the patterns formed in are arranged in two rows at predetermined intervals in the direction orthogonal to the scanning direction (Y direction). , PL3, PL5 and a step-and-scan type exposure apparatus that transfers onto a plate P via a projection optical system PL comprising two projection optical units (not shown) (hereinafter referred to as projection optical units PL2, PL4). Will be described.

  In the following description, the XYZ orthogonal coordinate system shown in each drawing is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. The XYZ orthogonal coordinate system is set so that the X axis and the Y axis are parallel to the plate P, and the Z axis is set in a direction orthogonal to the plate P. In the XYZ coordinate system in the figure, the XY plane is actually set to a plane parallel to the horizontal plane, and the Z axis is set to the vertical direction. In the present embodiment, the direction (scanning direction) in which the mask M and the plate P are moved is set in the X-axis direction.

  The scanning exposure apparatus shown in FIG. 1 includes an illumination optical system IL for uniformly illuminating a mask M placed on a mask stage (not shown). The illumination optical system IL includes an optical system 1 including a light source and a plurality of illumination optical units IL1 to IL5 arranged in two rows at predetermined intervals in a Y direction (predetermined direction) that is a direction orthogonal to the scanning direction. Yes. FIG. 2 is a diagram illustrating configurations of the optical system 1 and the illumination optical unit IL1. As shown in FIG. 2, the optical system 1 includes a light source 2 made of, for example, a mercury lamp or an ultrahigh pressure mercury lamp. The light beam emitted from the light source 2 is reflected by the elliptical mirror 3 and the dichroic mirror 4, passes through the shutter 5, becomes parallel light by passing through the collimating lens 6, and transmits only the light beam in a predetermined exposure wavelength region. Pass 7

  The light beam that has passed through the wavelength selection filter 7 is condensed by the condenser lens 8 onto the entrance 9 a of the light guide fiber 9. The light guide fiber 9 is a random light guide fiber configured by, for example, randomly bundling a large number of fiber strands, and includes an incident port 9a and five exit ports (hereinafter referred to as exit ports 9b, 9c, 9d, 9e, and 9f). Is provided.) The light beam incident on the incident port 9a of the light guide fiber 9 propagates through the inside of the light guide fiber 9, and then is divided and emitted from the five exit ports 9b to 9f. The predetermined irradiation areas I1 to I5 are formed on the mask M. It enters each of the five illumination optical units IL1 to IL5 forming (see FIG. 3).

  The light beam incident on the illumination optical unit IL1 passes through the collimator lens 10 constituting the illumination optical unit IL1 and passes through a number of element lenses constituting the optical integrator 11. Light beams from a large number of secondary light sources formed on the rear focal plane of the optical integrator 11 pass through the condenser lens 12 and illuminate the mask M almost uniformly. The illumination optical units IL2 to IL5 have the same configuration as that of the illumination optical unit IL1, and illuminate the mask M substantially evenly with light passing through them. A temperature measuring device 13 for measuring the temperature on the mask M is provided on the + X direction side of the illumination optical units IL1 to IL5 as shown in FIG.

  FIG. 3 is a diagram illustrating the configuration of the mask M and the temperature measuring device 13. The mask M has ten alignment marks a1 to a10 used for alignment with the pattern formation regions M1 to M5, the non-pattern formation regions m1 to m6, and the plate P. The pattern formation region M1 formed on the mask M follows the scanning of the mask M in the X direction (scanning direction), and the illumination region illuminated by the illumination optical unit IL1, that is, the trapezoidal shape formed by the illumination optical unit IL1. This is an area illuminated by the irradiation area I1. Similarly, each of the pattern formation regions M2 to M5 follows the scanning of the mask M in the X direction (scanning direction), and is illuminated by each of the illumination optical units IL2 to IL5, that is, the illumination optical units IL2 to IL5. Each of these is an area illuminated by each of the trapezoidal irradiation areas I2 to I5 formed. The non-pattern forming areas m1 to m6 on the mask M are areas where the pattern to be transferred on the plate P is not formed, and are non-illuminated areas that are not illuminated by any of the illumination optical units IL1 to IL5, that is, This is a region where the irradiation regions I1 to I5 are not formed during scanning.

  The temperature measuring device 13 includes five first radiation thermometers (first temperature measuring devices) T1 to T5 that measure the temperatures of the pattern formation regions M1 to M5 formed on the mask M. The temperature measuring device 13 includes six second radiation thermometers (second temperature measuring devices) t1 to t6 for measuring the temperatures of the non-pattern forming regions m1 to m6 where the pattern is not formed. Yes. As shown in FIG. 2, the first radiation thermometer T1 includes a temperature sensor 13b including a lens 13a and an infrared sensor, and measures the temperature in the pattern formation region M1. That is, the temperature of a predetermined region is collected by condensing infrared rays radiated from a predetermined region in the pattern formation region M1 passing under the first radiation thermometer T1 through the lens 13a during scanning. Measure. The configuration of the first radiation thermometers T2 to T5 is the same as that of the first radiation thermometer T1, and each of the pattern formation regions M2 to M5 that pass under each of the first radiation thermometers T2 to T5 during scanning. The temperature of each predetermined region is measured by measuring the amount of infrared radiation from the predetermined region.

  The second radiation thermometer t1 has the same configuration as the first radiation thermometer T1, and measures the temperature in the non-pattern formation region m1. That is, the temperature of a predetermined region is measured by condensing infrared rays radiated from a predetermined region in the non-pattern forming region m1 passing under the second radiation thermometer t1 to the temperature sensor through a lens during scanning. I do. The configuration of the second radiation thermometers t2 to t6 is the same as the configuration of the first radiation thermometer T1, and the non-pattern forming regions m2 to m6 that pass under the second radiation thermometers t2 to t6 during scanning. The temperature of each predetermined area is measured. That is, the first radiation thermometers T1 to T5 and the second radiation thermometers t1 to t6 measure the temperature of a predetermined region on the mask M without contact with the mask M.

  The mask stage (not shown) on which the mask M is placed is provided with a scanning drive system (not shown) having a long stroke for moving the mask stage along the X direction which is the scanning direction. Yes. In addition, a pair of alignment drive systems (not shown) are provided for moving the mask stage by a predetermined amount along the Y direction, which is a direction orthogonal to the scanning direction, and for rotating the mask stage by a minute amount around the Z axis. The position coordinate of the mask stage is measured and controlled by a laser interferometer (not shown) using a movable mirror (not shown).

  The light from each irradiation region I1 to I5 on the mask M is projected in plural (five in this embodiment) arranged in a staggered manner along the Y direction so as to correspond to each irradiation region I1 to I5. The light enters the projection optical system PL including the optical units PL1 to PL5. FIG. 4 is a diagram showing a configuration of the projection optical unit PL1. The light from the irradiation region I1 on the mask M is reflected by the reflecting surface 15a of the prism mirror 15 and reflected by the concave mirror 18 via the lenses 16 and 17. The light reflected by the concave mirror 18 is reflected again by the reflecting surface 15b of the prism mirror 15 via the lenses 16 and 17, and passes through the magnification adjusting lens group 20 for correcting the magnification of the image. The magnification adjusting lens group 20 includes a concave lens 20a and a convex lens 20b. The concave lens 20a and the convex lens 20b are movable in the optical axis direction (Z direction) of the projection optical unit PL1, and the interval in the optical axis direction is changed. It is configured to be able to. The magnification of the image formed on the plate P can be adjusted by moving at least one of the concave lens 20a and the convex lens 20b in the Z direction. The light that has passed through the magnification adjusting lens group 20 passes through an image position adjusting member group 21 for adjusting the position of the image. The image position adjusting member group 21 includes two parallel flat plates 21a and 21b, and the parallel flat plates 21a and 21b are configured to be tiltable with respect to the optical axis of the projection optical unit PL1. By tilting at least one of the plane parallel plates 21a and 21b with respect to the optical axis, the position of the image formed on the plate P can be shifted.

  The light that has passed through the image position adjusting member group 21 forms an image of the pattern of the mask M on a plate P that is supported in parallel with the XY plane via a plate holder (not shown) on a plate stage (not shown). That is, the projection optical unit PL1 forms a pattern image on the mask M illuminated by the irradiation area I1 in the exposure area R1 (see FIG. 5) on the plate P.

  The configuration of the projection optical units PL2 to PL5 is the same as that of the projection optical unit PL1, and the light that has passed through each projection optical unit PL2 to PL5 forms an image of the pattern of the mask M on the plate P. To do. That is, the projection optical units PL2 to PL5 form pattern images on the mask M illuminated by the irradiation regions I2 to I5 in the exposure regions R1 to R5 (see FIG. 5) on the plate P. In this embodiment, the projection optical units PL1 to PL5 have a magnification of 2 times. Therefore, an enlarged image of the pattern of the mask M is formed in each of the exposure regions R1 to R5 (see FIG. 5) arranged in two rows in the Y direction so as to correspond to the irradiation regions I1 to I5 on the plate P. . The image formed on the plate P by the projection optical units PL1 to PL5 is an inverted image that is inverted in the Y direction.

  A plate stage (not shown) on which the plate P is placed includes a scanning drive system (not shown) having a long stroke for moving the plate stage along the X-axis direction, which is the scanning direction, and a plate stage. Is provided with a pair of alignment drive systems (not shown) for moving the lens by a predetermined amount along the Y-axis direction, which is the orthogonal direction of scanning, and for rotating a small amount around the Z-axis. The position coordinate of the plate stage is measured by a laser interferometer (not shown) using the movable mirror 50 and the position is controlled. In this embodiment, the pattern of the mask M is magnified twice by the projection optical system PL and projected onto the plate P. Therefore, the projection stage PL is scanned with the mask stage and the plate stage at a scanning ratio of 1: 2. That is, according to the magnification of the projection optical system PL, the plate stage is scanned with respect to the mask stage at a speed ratio that is double the magnification. As a result, with respect to the scanning direction, the length of the pattern area of the mask M is enlarged to a length that is double the magnification and exposed to the plate P side.

  Further, as shown in FIG. 1, between the projection optical units PL1, PL3, and PL5 and the projection optical units PL2 and PL4, an alignment system 52 for aligning the plate P and a focus position of the plate P are provided. An autofocus system 54 for adjustment is arranged. An alignment microscope 56 is provided on a plate stage (not shown) at the end of the plate P in the + X direction. FIG. 5 is a diagram illustrating a configuration of the alignment microscope 56. As shown in FIG. 5, the alignment microscope 56 includes microscopes A1 to A6 arranged at predetermined intervals in the Y direction. Note that regions R1 to R5 shown in FIG. 5 are exposure regions formed on the plate P by the projection optical units PL1 to PL5, respectively. The interval between the microscopes A1 to A6 is the alignment mark image when the images of the alignment marks a1 to a10 on the mask M shown in FIG. 3 are enlarged twice and formed on the plate P via the projection optical system PL. It matches the interval.

  FIG. 6 is a diagram showing a system configuration of the scanning exposure apparatus according to this embodiment. The scanning exposure apparatus includes a control unit 60 that controls exposure processing. The control unit 60 is connected to an image magnification adjustment drive unit 62 for driving the concave lens 20a and the convex lens 20b constituting the image magnification adjustment lens group 20 of the projection optical unit PL1. The drive is controlled. Further, the control unit 60 is connected to an image position adjusting drive unit 64 for driving the plane parallel plates 21a and 21b constituting the image position adjusting member group 21 of the projection optical unit PL1, and the image position adjusting drive. The drive of the part 64 is controlled. In addition, the control unit 60 drives each image magnification adjustment lens group (not shown) and each image position adjustment member group (not shown) constituting each projection optical unit PL2 to PL5. (Not shown) and an image position adjustment drive unit (not shown), and controls the drive of each image adjustment drive unit and each image position adjustment drive unit.

  Further, the control unit 60 includes the temperature sensor 13b of the first radiation thermometer T1, the temperature sensor 13c of the first radiation thermometer T2, the temperature sensor 13d of the first radiation thermometer T3, and the first radiation. Temperature sensor 13e of thermometer T4, temperature sensor 13f of first radiation thermometer T5, temperature sensor 13g of second radiation thermometer t1, temperature sensor 13h of second radiation thermometer t2, temperature sensor of second radiation thermometer t3 13i, a temperature sensor 13j of the second radiation thermometer t4, a temperature sensor 13k of the second radiation thermometer t5, and a temperature sensor 13l of the second radiation thermometer t6, and the measurement results of the temperature sensors 13a to 13l are get. The control unit (calculator) 60 calculates the adjustment amount for the image forming state of the image formed by each of the projection optical units PL1 to PL5 using the measurement results of the temperature sensors 13a to 13l. In this embodiment, the position of the image and the magnification of the image are described as the image forming state. However, in the image forming state, image distortion due to the aberration of the projection optical system (due to distortion aberration), Image blur (spherical aberration, critical aberration, field curvature), image flow (coma aberration), and the like are included. Further, the control unit (adjuster) 60, based on the calculated adjustment amount, receives the concave lens 20a, the convex lens 20b, and the parallel plane plates 21a and 21b via the image adjustment driving unit 60, the image position adjustment driving unit 62, and the like. Etc. are adjusted to adjust the position of the image and the magnification of the image.

  Next, an exposure method of the scanning exposure apparatus according to this embodiment will be described with reference to the flowchart shown in FIG. When a pattern is transferred in the scanning exposure apparatus according to this embodiment, first, as shown in FIG. 8, images of alignment marks a3, a4, a7, and a8 formed by projection optical units PL2 and PL4. The image positions and image magnifications of the projection optical units PL2 and PL4 are adjusted so that ar3, ar4, ar7, and ar8 coincide with the centers of the visual fields of the microscopes A2 to A5. Next, as shown in FIG. 9, images ar1, ar2, ar5, ar6, ar9, ar10 of the alignment marks a1, a2, a5, a6, a9, a10 formed by the projection optical units PL1, PL3, PL5 are The image positions and image magnifications of the projection optical units PL1, PL3, and PL5 are adjusted so as to coincide with the centers of the visual fields of the microscopes A1 to A6.

  Then, while moving the mask M and the plate relative to the projection optical system PL, an enlarged image of the pattern formed in the pattern formation regions M1 to M5 of the mask M by the projection optical units PL1 to PL5 is displayed on the plate P. Transcript to.

  In the scanning exposure apparatus according to this embodiment, since it has the projection optical system PL having a magnification, the mask M has a region where a pattern is formed and a region where a pattern is not formed. The pattern formed on M is transferred to almost the entire surface of the plate P. Therefore, the plate P is irradiated with light substantially uniformly over the entire surface, but the mask M has a region irradiated with light and a region not irradiated with light, and a region irradiated with light and a region not irradiated with light. Difference in temperature occurs.

  Therefore, in the scanning exposure apparatus according to this embodiment, areas illuminated by light by the temperature measuring device 13, that is, pattern formation areas M1 to M5, and areas not illuminated by light, that is, non-pattern formation areas m1 to m6. And measure the temperature individually.

  First, the temperature in the pattern formation regions M1 to M5 illuminated by the illumination optical system IL (illumination optical units IL1 to IL5) on the mask M is measured (step S10, first temperature measurement step) and simultaneously on the mask M. The temperatures in the non-pattern forming regions m1 to m6 that are not illuminated by the illumination optical system IL (illumination optical units IL1 to IL5) are measured (step S11, second temperature measurement step).

  Specifically, the controller 60 scans the mask M in the X direction, the temperature change amount of the pattern formation region M1 measured by the temperature sensor 13b, and the temperature change amount of the pattern formation region M2 measured by the temperature sensor 13c. The temperature change amount of the pattern formation region M3 measured by the temperature sensor 13d, the temperature change amount of the pattern formation region M4 measured by the temperature sensor 13e, the temperature change amount of the pattern formation region M5 measured by the temperature sensor 13f, and the temperature A temperature change amount of the non-pattern formation region m1 measured by the sensor 13g, a temperature change amount of the non-pattern formation region m2 measured by the temperature sensor 13h, a temperature change amount of the non-pattern formation region m3 measured by the temperature sensor 13i, The temperature change amount of the non-pattern forming region m4 measured by the temperature sensor 13j, the temperature sensor Temperature change amount of the non-pattern formation region m5 measured by 3k, and obtains the temperature change amount of the non-pattern formation region m6 measured by the temperature sensor 13l.

  Next, the control unit 60 uses the temperatures of the pattern formation regions M1 to M5 and the non-pattern formation regions m1 to m6 on the mask M acquired in Step S10 and Step S11, respectively, for each of the projection optical units PL1 to PL5. The adjustment amount for the image formation state of the image formed by the above (in this embodiment, the image position and the image magnification) is calculated (step S12, calculation step).

Here, the temperature change amount of the pattern formation region M1 is ΔT1, the temperature change amount of the pattern formation region M2 is ΔT2, the temperature change amount of the pattern formation region M3 is ΔT3, the temperature change amount of the pattern formation region M4 is ΔT4, and the pattern formation region The temperature change amount of M5 is ΔT5, the temperature change amount of the non-pattern formation region m1 is Δt1, the temperature change amount of the non-pattern formation region m2 is Δt2, the temperature change amount of the non-pattern formation region m3 is Δt3, and the non-pattern formation region m4 The temperature change amount is Δt4, the temperature change amount of the non-pattern formation region m5 is Δt5, the temperature change amount of the non-pattern formation region m6 is Δt6, the expansion coefficient of the substrate constituting the mask M is α, and the mask M is irradiated. the length in the Y direction of the irradiation region Wm ₀ (see FIG. 10), (see FIG. 10) Wp width of the exposure area formed on the plate P, the non-irradiation on the mask M Reference length in the Y direction pass (gap) and Wg ₀ (see FIG. 10).

  First, displacement amounts ΔWm1 to ΔWm5 of the lengths in the Y direction of the respective illumination regions of the illumination optical units IL1 to IL5 are calculated from the equation (1).

ΔWmn = α × ΔTn × Wm ₀ (n = 1, 2, 3, 4, 5) (1)
Since the desired exposure width of one projection optical unit is Wp, the projection magnifications β1 to β5 of the projection optical units PL1 to PL5 are expressed by equation (2) using the calculation result calculated from equation (1). Is done.

| Βn | = {Wp / (Wm ₀ + ΔWmn)} (n = 1, 2, 3, 4, 5) (2)
Next, the elongation amount Δall of the mask M in the Y direction is calculated from the equation (3).

Δall = α × {Wm ₀ × (ΔT1 + ΔT2 + ΔT3 + ΔT4 + ΔT5) + Wg ₀ × (Δt1 + Δt2 + Δt3 + Δt4 + Δt5 + Δt6)} (3)
Here, the extension amount of the mask M in the Y direction will be described with reference to FIGS. 11 and 12. As shown in FIGS. 11 and 12, the mask M is fixed on the mask holders MHA and MHB mounted on the mask stage MST, and the mask stage MST is controlled to a desired position by the interferometer 70. 11 and 12, only the interferometer that controls the position in the Y direction is shown.

  In FIG. 11, the mask holders MHA and MHB are made of a material having relatively low rigidity. When the mask M expands by being irradiated with illumination light, the mask M is held while the mask holders MHA and MHB at both ends are deformed to substantially the same extent, and the center position of the mask M with respect to the mask holders MHA and MHB changes substantially. Instead, the positions of the exposure regions R1 to R5 on the plate P change in the direction indicated by the arrows in the figure in proportion to the distance from the center MC of the mask M to the field of view center of each projection optical unit PL1 to PL5. Therefore, the adjustment amounts ΔS1 to ΔS5 in the Y direction of the image positions of the projection optical systems PL1 to PL5 are calculated by the equation (4).

ΔSn = {(Δall / Mall) × Ln} × | βn | (n = 1, 2, 3, 4, 5) (4)
However, Ln (n = 1, 2, 3, 4, 5) has the center of the mask M as the origin, and the distance in the Y direction between the origin and the center of the visual field of each projection optical unit PL1 to PL5, Mall is not The total width in the Y direction of the mask M at the time of irradiation.

  When the image magnification βn of the projection optical system PL is a positive value, ΔSn may be adjusted by ΔSn with respect to the direction in which the center of the mask M is away from the center of the corresponding plate P as +. When βn is a negative value, ΔSn may be adjusted by ΔSn with respect to a direction in which the center of the mask M is away from the center of the corresponding plate P.

  In FIG. 12, when the rigidity of one of the mask holders MHA and MHB is intentionally lowered, or a vacuum chuck that holds the mask holder MHA and the mask M by suction, or the mask holder MHB and the mask M are held by suction. In this case, the vacuum chuck is intentionally weakened and the escape of the mask M against expansion and contraction is assumed.

  For example, the mask holder MHB is fixed by a vacuum chuck having a suction force much smaller than that of the mask holder MHA. When the mask M expands or contracts, the mask holder MHB slides on the holding surface of the mask holder MHB and changes When the structure can absorb the minute, the exposure regions R1 to R5 on the plate P in the direction indicated by the arrows in the figure in proportion to the distance from the mask holder MHA to the center of the visual field of each projection optical unit PL1 to PL5. The position of changes. Accordingly, the image position adjustment amounts ΔS1 to ΔS5 of the projection optical systems PL1 to PL5 are calculated by the equation (5).

ΔSn = {(Δall / Mall) × Dn} × | βn | (n = 1, 2, 3, 4, 5) (5)
However, Dn is a distance in the Y direction between the origin and the center of the field of view of each projection optical unit PL1 to PL5 with the origin on the mask holder MHA side of the mask M. When the image magnification βn of the projection optical system PL is a positive value, ΔSn may be adjusted by ΔSn with respect to the direction away from the mask holder MHA, and when the image magnification βn is a negative value. ΔSn may be adjusted by ΔSn with respect to the direction away from the mask holder MHA as −.

  In the above description, the correction amount of the image position is obtained using the total elongation amount Δall. However, the correction amount may be obtained from Δt, ΔT, Ln, and Dn for each module. Thereby, the correction amount of the image position can be obtained more accurately.

  Next, the image positions and image magnifications of the projection optical units PL1 to PL5 are adjusted using the adjustment amount calculated in step S12 (step S13, adjustment process).

  Specifically, using the calculation result calculated from the expression (2), the magnification adjustment lens group constituting each of the projection optical units PL1 to PL5 is driven via the image magnification adjustment drive unit 62 and the like, and each projection is performed. The image magnification of the optical units PL1 to PL5 is adjusted. When the rigidity of both ends in the Y direction of the mask M is low, the projection optical units PL1 to PL5 are connected via the image position adjustment drive unit 64 and the like using the calculation result calculated by the equation (4). The image position adjustment member group which comprises is driven, and the image position of each projection optical unit PL1-PL5 is adjusted. When the rigidity of both ends in the Y direction of the mask M is different, the projection optical units PL1 to PL5 are connected via the image position adjusting drive unit 64 and the like using the calculation result calculated by the equation (5). Is driven to adjust the image positions of the projection optical units PL1 to PL5.

  Next, the pattern formed on the mask M is enlarged and exposed on the plate P using the projection optical units PL1 to PL5 that have finished adjusting the image magnification and the image position in step S12. According to the exposure method described above, it is possible to prevent a reduction in exposure accuracy due to exposure of a mask pattern deformed due to a temperature change, and to perform good exposure.

  According to the temperature measurement device 13 according to this embodiment, the first radiation thermometers T1 to T5 that measure the temperatures of the pattern formation regions M1 to M5 illuminated by the illumination optical system IL and the illumination optical system IL are not illuminated. Since the second radiation thermometers t1 to t6 that measure the temperatures of the non-pattern forming regions m1 to m6 are provided, the temperatures of the pattern forming regions M1 to M5 and the temperatures of the non-pattern forming regions m1 to m6 are accurately measured. Therefore, the temperature difference between the pattern formation regions M1 to M5 and the non-pattern formation regions m1 to m6 can be accurately detected. Therefore, in the scanning exposure apparatus according to this embodiment, since the deformation amount due to the temperature change of the mask M can be accurately detected, the image forming state of the projection optical system PL can be adjusted appropriately, Decrease in exposure accuracy due to deformation of mask M, for example, decrease in splicing accuracy of splicing region formed by overlapping a part of an image formed by projection optical units PL1 to PL5 on plate P, pattern line width Variation, and deterioration in overlay accuracy of overlay exposure of each layer can be prevented.

  Note that the image magnification and image position adjustment based on the temperature difference between the pattern formation regions M1 to M5 and the non-pattern formation regions m1 to m6 of the mask according to this embodiment may be performed at predetermined time intervals or at predetermined intervals. It may be performed each time a pattern is transferred to a number of plates.

  Further, in this embodiment, five first radiation thermometers T1 to T5 for measuring the temperature in the pattern formation regions M1 to M5, that is, the illumination region are provided, but at least one first radiation thermometer is provided. The temperature of at least one point in the illumination area may be measured. In addition, although six second radiation thermometers t1 to t6 for measuring the temperature in the non-pattern forming regions m1 to m6, that is, in the non-illuminated region, are provided, at least one second radiation thermometer is provided and non-illuminated. The temperature of at least one point in the region may be measured.

  In this embodiment, the temperature of a predetermined region on the mask M is measured by the radiation thermometers T1 to T5 and t1 to t6. An element that changes color depending on the temperature is attached to the pattern formation regions m1 to m6, and an observation device for observing the change in the color is provided. Temperature measurement of a predetermined region on the mask M is performed based on the observation result by the observation device. You may make it perform. Further, for example, the refractive index in the pattern formation regions M1 to M5 and the non-pattern formation regions m1 to m6 on the mask M is measured in real time by ellipsometry (polarization analysis), and the measurement result and the refractive index of the material constituting the mask M are measured. Alternatively, the temperature of a predetermined region on the mask M may be detected from the temperature coefficient. In addition, a detection device for detecting light from one end of the mask M, which is incident at an angle that substantially totally reflects light, such as laser light, from the other end, is detected by the detection device. You may detect the temperature of the predetermined area | region on the mask M from change, such as a light quantity and the intensity | strength of leaked light. In any case, the temperature of a predetermined region on the mask M can be measured without contact with the mask M.

  In this embodiment, the image position and the image magnification as the image forming state of the image formed by the projection optical units PL1 to PL5 are adjusted, but the projection optical units PL1 to PL5 as the image forming state are adjusted. Image distortion due to distortion of the image, spherical aberration, astigmatism, image blur due to field curvature, and image flow due to coma aberration may be adjusted.

  In the scanning exposure apparatus according to the above-described embodiment, a micropattern (semiconductor element) is formed by exposing a transfer pattern formed by a mask using a projection optical system to a photosensitive substrate (plate) (exposure process). , Imaging devices, liquid crystal display devices, thin film magnetic heads, and the like). Hereinafter, an example of a technique 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 scanning exposure apparatus according to the above-described embodiment will be described with reference to FIG. This will be described with reference to the flowchart of FIG.

  First, in step S301 of FIG. 13, 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, the image of the pattern formed by the mask is part 1 through the projection optical system in which the image position and the image magnification are adjusted using the scanning exposure apparatus according to the above-described embodiment. The exposure transfer is sequentially performed on each shot area on the plate of the lot. After that, in step S304, the photoresist on the one lot of plates is developed, and in step S305, the resist pattern is used as an etching mask on the one lot of plates to form the mask. A circuit pattern corresponding to the pattern is formed in each shot area on each plate.

  Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the semiconductor device manufacturing method described above, since the exposure is performed by the exposure method using the scanning exposure apparatus according to the above-described embodiment, high-precision exposure can be performed and a good semiconductor device can be obtained. Can do. 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 this 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. 14, in a pattern forming process 401, a so-called photolithography process is performed in which a mask pattern is transferred and exposed to a plate using the scanning exposure apparatus according to this embodiment. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the plate. Thereafter, the exposed plate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the plate, and the process proceeds to the next color filter forming step 402.

  Next, in the color filter forming step 402, a large number of sets 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 forming step 402, a cell assembling step 403 is executed. In the cell assembling step 403, a liquid crystal panel (liquid crystal cell) is assembled using the plate having the predetermined pattern obtained in the pattern forming step 401, the color filter obtained in the color filter forming step 402, and the like. In the cell assembly step 403, for example, liquid crystal is injected between the plate having the predetermined pattern obtained in the pattern formation step 401 and the color filter obtained in the color filter formation step 402, and a liquid crystal panel (liquid crystal cell) is obtained. ).

  Thereafter, in a module assembling step 404, 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 by the exposure method using the scanning exposure apparatus according to the above-described embodiment, high-precision exposure can be performed, and a good liquid crystal display element can be obtained. Obtainable.

  The embodiments described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

1 is a perspective view showing a schematic configuration of a scanning exposure apparatus according to an embodiment. It is a figure which shows the structure of the illumination optical system concerning embodiment. It is a figure which shows the structure of the mask concerning embodiment, and a temperature measurement apparatus. It is a figure which shows the structure of the projection optical unit concerning Embodiment. It is a figure which shows the structure of the alignment system concerning embodiment. It is a figure which shows the system configuration | structure of the scanning exposure apparatus concerning Embodiment. It is a figure for demonstrating the exposure method using the scanning exposure apparatus concerning embodiment. It is a figure for demonstrating the positional relationship of an alignment microscope and an alignment mark. It is a figure for demonstrating the positional relationship of an alignment microscope and an alignment mark. It is a figure for demonstrating the parameter for calculating adjustment amount. It is a figure which shows the structure of a mask holder, and the state of expansion | extension of a mask. It is a figure which shows the structure of a mask holder, and the state of the expansion | extension of a mask. 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

  DESCRIPTION OF SYMBOLS 1 ... Optical system, 2 ... Light source, 3 ... Elliptic mirror, 4 ... Dichroic mirror, 5 ... Shutter, 6 ... Collimating lens, 7 ... Wavelength selection filter, 8 ... Condensing lens, 9 ... Light guide fiber, 10 ... Collimating lens DESCRIPTION OF SYMBOLS 11 ... Optical integrator, 12 ... Condenser lens, 13 ... Temperature measuring device, 13b-13l ... Temperature sensor, 15 ... Prism mirror, 16, 17 ... Lens, 18 ... Concave mirror, 20 ... Magnification adjustment lens group, 21 ... Image position Adjustment member group, 52 ... alignment system, 54 ... autofocus system, 56 ... alignment microscope, 60 ... control unit, 62 ... image magnification adjustment drive unit, 64 ... image position adjustment drive unit, 70 ... interferometer, A1 to A1- A6 ... Microscope, IL ... Illumination optical system, IL1-IL5 ... Illumination optical unit, M ... Mask, MST ... Mask stage, MHA, M B ... Mask holder, M1-M5 ... Pattern formation region, m1-m6 ... Non-pattern formation region, P ... Plate, T1-T5 ... First radiation thermometer, t1-t6 ... Second radiation thermometer, PL ... Projection optics System, PL1 to PL5: Projection optical unit.

Claims (11)

A temperature measuring device for measuring a temperature of an original plate having a pattern forming region on which a pattern to be transferred is formed,
A first temperature measuring device for measuring the temperature of at least one point in the pattern formation region;
A second temperature measuring device for measuring a temperature of at least one point in a non-pattern forming region where a pattern to be transferred is not formed;
A temperature measuring device comprising: The original is illuminated by an illumination optical system,
The first temperature measuring device measures a temperature of at least one point in an illumination area on the original plate illuminated by the illumination optical system;
The temperature measuring apparatus according to claim 1, wherein the second temperature measuring device measures a temperature of at least one point in a non-illuminated area on the original plate that is not illuminated by the illumination optical system. A temperature measuring device having a predetermined pattern and measuring the temperature of an original plate illuminated by an illumination optical system,
A first temperature measuring device for measuring a temperature of at least one point in an illumination area on the original plate illuminated by the illumination optical system;
A second temperature measuring device for measuring a temperature of at least one point in a non-illuminated area on the original that is not illuminated by the illumination optical system;
A temperature measuring device comprising: The illumination optical system includes a plurality of illumination optical units arranged at predetermined intervals in a predetermined direction,
4. The temperature measuring device according to claim 2, wherein the first temperature measuring device measures a temperature in each illumination area on the original plate illuminated by each of the plurality of illumination optical units. .   5. The temperature measurement according to claim 4, wherein the second temperature measuring device measures a temperature in each non-illuminated area between illuminated areas on the original plate illuminated by each of the plurality of illumination optical units. apparatus.   The at least one of the first temperature measuring device and the second temperature measuring device measures the temperature of the at least one point on the original plate in a non-contact manner with the original plate. The temperature measuring device according to any one of the above. A scanning type in which a pattern formed on an original illuminated by an illumination optical system is transferred onto an irradiated body via a plurality of projection optical systems having magnifications arranged at predetermined intervals in a direction intersecting the scanning direction. An exposure apparatus,
A scanning type exposure apparatus comprising the temperature measuring apparatus according to claim 1. A calculator that calculates an adjustment amount for an image forming state of an image formed by each of the plurality of projection optical systems using measurement results of the first temperature measuring device and the second temperature measuring device;
An adjuster for adjusting the image forming state based on the adjustment amount calculated by the calculator;
The scanning exposure apparatus according to claim 7, further comprising:   9. The scanning exposure apparatus according to claim 8, wherein the image forming state has at least one of the position of the image and the magnification of the image. A scanning type in which a pattern formed on an original plate illuminated by an illumination optical system is transferred onto an irradiated object via a plurality of projection optical systems having magnifications arranged at predetermined intervals in a direction intersecting the scanning direction. An exposure method for performing exposure using an exposure apparatus,
A first temperature measurement step of measuring a temperature of at least one point in an illumination area illuminated by the illumination optical system on the original plate;
A second temperature measuring step of measuring a temperature of at least one point in a non-illuminated area that is not illuminated by the illumination optical system on the original plate;
A calculation step of calculating an adjustment amount for an image forming state of an image formed by each of the plurality of projection optical systems based on measurement results of the first temperature measurement step and the second temperature measurement step;
An adjustment step of adjusting the image forming state based on the adjustment amount calculated by the calculation step;
An exposure method comprising: An exposure step of exposing a pattern on a photosensitive substrate using the exposure method according to claim 10;
A developing step of developing the photosensitive substrate exposed by the exposing step;
A device manufacturing method comprising:

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