Substrate processing apparatus

Abstract

To provide a technique capable of accurately and inexpensively measuring the position of a moved stage.SOLUTION: An exposure device 100 includes a stage 2, a stage moving mechanism 3, a first coil group 611, a first magnet 631, an electromotive force measurement device 65, and a position calculation part 97. The stage 2 holds a substrate W. The stage moving mechanism 3 moves the stage 2 in a Y direction. A plurality of coils 71 of the first coil group 611 are fixed to the stage 2, and are arrayed at intervals in the Y direction. The first magnet 631 is fixed at a position which is separated from the stage 2 and can face the first coil group 611. The electromotive force measurement device 65 measures an induced electromotive force generated in the first coil group 611 by a magnetic flux from the first magnet 631. The position calculation part 97 calculates the position in the Y direction of the stage 2, on the basis of the induced electromotive force measured by the electromotive force measurement device 65.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The subject matter disclosed in this specification relates to a substrate processing apparatus.

Background Art

[0002] For example, as a method of forming a pattern on a substrate such as a semiconductor wafer or a glass substrate, an exposure apparatus that performs direct drawing by light irradiation is known. In this type of exposure apparatus, a substrate on which a photosensitive layer such as a resist is formed is held by a stage, and the stage is moved in the main scanning direction. Then, according to the position of the stage in the main scanning direction, pattern light is emitted from an exposure head, and a predetermined pattern is drawn on the photosensitive layer.

[0003] When the stage is moved in such an exposure apparatus, the stage may meander or the stage may be displaced in an unexpected direction. When such displacement occurs, the pattern may not be formed as specified, and distortion may occur in the pattern. Therefore, techniques for correcting unexpected displacement of the stage have been proposed so far.

[0004] For example, Patent Document 1 discloses a mask stage that controls the coordinates of a mask with high precision. Specifically, a beam splitter is fixed on a mask table on which a mask is placed, and the position of the mask table is detected by measuring the position of the beam splitter with a laser interferometer fixed to a surface plate. A sensor for measuring the distance or displacement amount to the mask is attached to the beam splitter. When the mask table on which the mask is placed is moved, the position information measured by the laser interferometer is corrected using the distance information or displacement information detected by the sensor means.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when measuring the position of the stage using a laser interferometer, if the measurement range of the laser interferometer becomes large, the laser light is likely to be affected by air fluctuations, temperature unevenness, etc., and there is a risk that the measurement accuracy will decrease. In addition, a laser interferometer with a large measurement range may require a high-power laser or a complex optical system, and is generally expensive. For this reason, there was also a problem that the device cost would increase significantly.

[0007] An object of the present invention is to provide a technology capable of accurately and at low cost measuring the position of a moving stage.

Means for Solving the Problems

[0008] To solve the above problems, a first aspect is a substrate processing apparatus, comprising a stage for supporting a substrate, a stage moving mechanism for moving the stage in a first direction, a plurality of first coils fixed to the stage and arranged at intervals in the first direction, a first magnet fixed at a position separated from the stage and opposed to the plurality of first coils, an electromotive force measuring device for measuring the induced electromotive force generated in the plurality of first coils by the magnetic flux from the first magnet, and a position calculating unit for calculating the position of the stage in the first direction based on the induced electromotive force measured by the electromotive force measuring device.

[0009] A second aspect is the substrate processing apparatus according to the first aspect, further comprising a plurality of second coils fixed to the stage and arranged at intervals in the first direction, and a second magnet fixed at a position separated from the stage and opposed to the plurality of second coils, wherein the plurality of second coils are located at a distance from the plurality of first coils in a second direction intersecting the first direction, and the electromotive force measuring device can measure the induced electromotive force generated in the plurality of second coils by the magnetic flux from the second magnet.

[0010] Aspect 3 is the substrate processing apparatus of Aspect 1 or Aspect 2, further comprising: a third plurality of coils fixed to the stage and arranged at intervals in a third direction intersecting the first direction; and a third magnet fixed at a position away from the stage and opposed to the third plurality of coils. The stage moving mechanism is capable of moving the stage in the third direction, and the electromotive force measuring device is capable of measuring the induced electromotive force generated in the third plurality of coils by the magnetic flux from the third magnet.

[0011] Aspect 4 is the substrate processing apparatus of Aspect 1 or Aspect 2, wherein the first plurality of coils are fixed to the bottom surface of the stage.

[0012] Aspect 5 is a substrate processing apparatus, comprising: a stage for supporting a substrate; a stage moving mechanism for moving the stage in a first direction; a first magnet fixed to the stage; a first plurality of coils fixed at a position away from the stage and opposed to the first magnet and arranged at intervals in the first direction; an electromotive force measuring device for measuring the induced electromotive force generated in the first plurality of coils by the magnetic flux of the first magnet; and a calculation unit for calculating the position of the stage in the first direction based on the induced electromotive force measured by the electromotive force measuring device. kk

[0013] Aspect 6 is the substrate processing apparatus of Aspect 1 or Aspect 5, wherein the first magnet is an electromagnet.

[0014] Aspect 7 is the substrate processing apparatus of Aspect 1 or Aspect 5, wherein the stage is a non-conductive member.

[0015] Aspect 8 is the substrate processing apparatus of Aspect 1 or Aspect 5, wherein the electromotive force measuring device has a filter capable of removing noise from the measured induced electromotive force.

[0016] A ninth aspect is the substrate processing apparatus according to the first aspect or the fifth aspect, further comprising an exposure head capable of exposing the substrate supported by the stage that moves in the first direction by the stage moving mechanism.

Advantages of the Invention

[0017] According to the substrate processing apparatus of the first aspect, an induced electromotive force is generated in each coil as each coil passes near the first magnet. Therefore, based on the measured induced electromotive force, the position of the stage in the first direction can be measured. Also, since it is not affected by air fluctuations like a laser length measuring system, the position of the stage in the first direction can be measured accurately and at low cost.

[0018] According to the substrate processing apparatus of the second aspect, the rotation angle and rotation direction of the stage about an axis in a direction intersecting the first direction and the second direction can be detected.

[0019] According to the substrate processing apparatus of the third aspect, the stage position in the third direction can be detected.

[0020] According to the substrate processing apparatus of the sixth aspect, even when the stage is stopped, by turning the electromagnet on and off, the magnetic flux passing through each coil can be changed. Thereby, since an induced electromotive force can be generated, the position of the stage can be measured.

[0021] According to the substrate processing apparatus of the seventh aspect, measurement errors can be reduced.

[0022] According to the substrate processing apparatus of the eighth aspect, since fluctuations in the induced electromotive force due to noise from the stage moving mechanism can be reduced, the position measurement accuracy of the stage can be improved.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the components described in this embodiment are merely examples, and are not intended to limit the scope of the present invention thereto. In the drawings, for ease of understanding, the dimensions and numbers of each part may be exaggerated or simplified as appropriate.

[0025] In the drawings, for ease of understanding the positional relationship of each element, arrows indicating the X direction, Y direction, and Z direction orthogonal to each other are appropriately attached. In the following description, the X direction and the Y direction are taken as the horizontal directions, and the Z direction is taken as the vertical direction. Also, the +Z direction is taken as the upward direction, and the -Z direction is taken as the downward direction for explanation.

[0026] <1. First Embodiment> FIG. 1 is a perspective view showing an exposure apparatus 100 according to the first embodiment. The exposure apparatus 100 is a substrate processing apparatus for processing a substrate W, and is an apparatus that irradiates light onto the upper surface of the substrate W on which a layer (photosensitive layer) of a photosensitive material such as a resist is formed to draw a pattern. The substrate W is, for example, a semiconductor substrate, a printed circuit board, a substrate for a color filter, a glass substrate for a flat panel display used in a liquid crystal display device or a plasma display device, or a substrate for an optical disk. The exposure apparatus 100 includes a base 1, a stage 2, a stage moving mechanism 3, a gantry 4, an exposure unit 5, a position measurement unit 6, and a control unit 9.

[0027] The base 1 has a rectangular shape in a top view. The base 1 supports the stage 2, the stage moving mechanism 3, and the gantry 4 from below.

[0028] The stage 2 includes a support stage 21, an X stage 23, and a Y stage 25. The support stage 21 has an upper surface 2S as a support surface for supporting the substrate W. The upper surface 2S is a horizontal plane parallel to the X direction and the Y direction. The substrate W is placed on the upper surface 2S in a horizontal posture. A plurality of suction holes are formed in the upper surface 2S. The support stage 21 can fix the substrate W to the upper surface 2S by applying a negative pressure (suction pressure) to the suction holes. Note that a chuck for gripping the periphery of the substrate W may be provided on the upper surface 2S, and the substrate W may be fixed to the upper surface 2S by the chuck.

[0029] The X stage 23 is disposed below the support stage 21 and rotatably supports the support stage 21. Also, the X stage 23 is located above the Y stage 25. The Y stage 25 is disposed below the X stage 23 and supports the X stage 23 and the sub-scanning mechanism 32.

[0030] The stage moving mechanism 3 is a mechanism that moves the support stage 21 in the main scanning direction (Y direction), sub-scanning direction (X-axis direction), and rotational direction (rotational direction around the Z-axis (θ-axis direction)). The stage moving mechanism 3 includes a sub-scanning mechanism 32, a main scanning mechanism 34, and a rotational mechanism 35.

[0031] The sub-scanning mechanism 32 moves the X stage 23 relative to the Y stage 25 in the X direction, which is the sub-scanning direction. The main scanning mechanism 34 moves the Y stage 25 relative to the base 1 in the Y direction, which is the main scanning direction. The sub-scanning mechanism 32 and the main scanning mechanism 34 are constituted by, for example, a linear motor mechanism including a linear motor and a guide, or a ball screw mechanism including a rotary motor, a ball screw, and a guide. The rotational mechanism 35 is provided on the X stage 23 and rotates the support stage 21 about the rotation axis A1 extending in the Z direction. The sub-scanning mechanism 32, the main scanning mechanism 34, and the rotational mechanism 35 operate based on control commands from the control unit 9.

[0032] The gantry 4 is fixed to the base 1. The gantry 4 has two support column portions 41 and a beam portion 43. The lower part of the support column portion 41 is fixed to the base 1 and extends in the Z direction. The two support column portions 41 are arranged at intervals in the X direction. The beam portion 43 connects the upper parts of the two support column portions 41 and extends in the X direction. In this example, the support stage 21 and the Y stage 25 of the stage moving mechanism 3 are arranged between the two support column portions 41 in the X direction, and the beam portion 43 is arranged above the support stage 21.

[0033] The gantry 4 is a member that supports the exposure unit 5. Each exposure head 51 of the exposure unit 5 described later is fixed to the -Y side surface of the beam portion 43 of the gantry 4.

[0034] The exposure unit 5 has one or more exposure heads 51. In this example, five exposure heads 51 are arranged along the X-axis direction. Each exposure head 51 has a spatial light modulator 510. The spatial light modulator 510 modulates laser light based on strip data corresponding to the drawing pattern.

[0035] The exposure unit 5 has a light irradiation unit 53. The light irradiation unit 53 irradiates the exposure head 51 with laser light. The light irradiation unit 53 is accommodated, for example, inside the gantry 4. The light irradiation unit 53 includes a laser drive unit 531, a laser oscillator 533, and an illumination optical system 535. By the operation of the laser drive unit 531, the laser oscillator 533 emits laser light to the illumination optical system 535. The illumination optical system 535 performs operations such as magnification change of the laser light incident from the laser oscillator 533 and uniformization of the light quantity distribution. The laser light emitted from the illumination optical system 535 is irradiated onto the spatial light modulator 510 of each exposure head 51.

[0036] The spatial light modulator 510 spatially modulates the laser light irradiated from the light irradiation unit 53 in channel units, and reflects the necessary light that contributes to pattern drawing and the unnecessary light that does not contribute to pattern drawing in different directions from each other. Note that spatially modulating light means changing the spatial distribution (amplitude, phase, polarization, etc.) of light. The exposure head 51 projects the modulated laser light onto the substrate W that moves directly below the exposure head 51. Thereby, the drawing pattern is exposed on the unprocessed substrate W.

[0037] For the spatial light modulator 510, a diffractive grating type optical element such as a GLV (Grating Light Valve, registered trademark of Silicon Light Machines, USA) or a DMD (Digital Mirror Device) can be used, for example.

[0038] The position measurement unit 6 is a device for measuring the position of the stage 2. The position measurement unit 6 includes a first coil group 611, a second coil group 612, a third coil group 613, a first magnet 631, a second magnet 632, a third magnet 633, and a plurality of electromotive force measuring devices 65.

[0039] The first coil group 611, the second coil group 612, and the third coil group 613 each include a plurality of coils 71 arranged in a row along the Y direction. Each coil 71 of the first coil group 611, the second coil group 612, and the third coil group 613 preferably has the same configuration. The coil 71 includes a wire wound in a spiral shape. The diameter of the coil 71 is, for example, 10 mm.

[0040] The number of coils 71 in the first coil group 611 and the second coil group 612 is appropriately set according to the size of the Y stage 25. For example, when the length of the Y stage 25 in the Y direction is 500 mm, the number of coils 71 in the first coil group 611 and the second coil group 612 may be 50 each (total 100).

[0041] In the Y direction, the position of the coil 71 on the most +Y side of the first coil group 611 is the same as the position of the coil 71 on the most +Y side of the second coil group 612. Also, in the Y direction, the interval between the coils 71 of the first coil group 611 is the same as the interval between the coils 71 of the second coil group 612. For this reason, in the Y direction, the position of each coil 71 of the first coil group 611 is the same as the position of each coil 71 of the second coil group 612.

[0042] Note that in the Y direction, the position of each coil 71 of the first coil group 611 may be different from the position of each coil 71 of the second coil group 612. Also, the interval between the coils 71 in the first coil group 611 and the second coil group 612 (hereinafter referred to as "coil interval") may be different. Also, it is not essential that the coil interval is constant. For example, the first coil group 611 may have a plurality of coils 71 arranged at a first interval and a plurality of coils 71 arranged at a second interval smaller than the first interval. In this way, by reducing the coil interval, the position calculation accuracy by the position calculation unit 97 described later can be improved. For example, the coil interval in the region where the substrate W is held in the Y direction may be made smaller than the coil interval in other regions. Thereby, while improving the calculation accuracy of the position for the region where the substrate W is arranged, the total number of coils 71 can be reduced.

[0043] FIG. 2 is a top view schematically showing a Y stage 25, a first coil group 611, and a second coil group 612. Each coil 71 of the first coil group 611 and the second coil group 612 is wound in a spiral around an axis parallel to the Z axis and is flat in a horizontal view as viewed from the X direction or the Y direction. That is, the coil axes of the coils 71 of the first coil group 611 and the second coil group 612 are parallel to the Z axis.

[0044] The first coil group 611 and the second coil group 612 are attached to the lower surface (-Z side surface) of the Y stage 25. In the Z direction, a gap larger than the coil 71 is formed between the base 1 and the Y stage 25. Each coil 71 of the first coil group 611 and the second coil group 612 is located away from the upper surface of the base 1 in the +Z direction. When the Y stage 25 moves in the Y direction, the first coil group 611 and the second coil group 612 also move in the Y direction together with the Y stage 25.

[0045] The first magnet 631 and the second magnet 632 are fixed to the upper surface of the base 1. The first magnet 631 and the second magnet 632 are preferably arranged at the same position in the Y direction. The first magnet 631 and the second magnet 632 are permanent magnets such as neodymium magnets, for example. The first magnet 631 and the second magnet 632 are located away from the first coil group 611 and the second coil group 612 fixed to the Y stage 25 in the -Z direction.

[0046] In the first magnet 631 and the second magnet 632, the N pole is directed upward (toward the Y stage 25 side), and the S pole is directed downward. Note that in the first magnet 631 and the second magnet 632, the N pole may be directed downward and the S pole may be directed upward.

[0047] When the Y stage 25 moves in the Y direction, each coil 71 of the first coil group 611 passes above the first magnet 631. That is, the first magnet 631 is arranged so as to be able to face the first coil group 611 in the Z direction. Also, when the Y stage 25 moves in the Y direction, each coil 71 of the second coil group 612 passes above the second magnet 632. That is, the second magnet 632 is arranged so as to be able to face the second coil group 612 in the Z direction.

[0048] When each coil 71 of the first coil group 611 approaches or separates from the first magnet 631, the magnetic flux density from the first magnet 631 passing through each coil 71 changes. As a result, an induced electromotive force is generated in each coil 71 of the first coil group 611. Also, when each coil 71 of the second coil group 612 approaches or separates from the second magnet 632, the magnetic flux from the second magnet 632 passing through the coil 71 changes. As a result, an induced electromotive force is generated in each coil 71 of the second coil group 612. The amount of change in the magnetic flux density passing through the coil 71 depends on the moving speed of the coil 71. For this reason, the magnitude of the induced electromotive force generated in the coil 71 changes according to the moving speed of the coil 71 with respect to the first magnet 631. The induced electromotive forces generated in each coil 71 of the first coil group 611 and the second coil group 612 are measured by an electromotive force measuring device 65 (see FIG. 4), respectively.

[0049] FIG. 3 is a top view schematically showing the X stage 23 and the third coil group 613. The third coil group 613 is attached to the lower surface (-Z side surface) of the X stage 23. Each coil 71 of the third coil group is wound in a spiral around an axis parallel to the Z axis and is flat in a horizontal view. That is, the coil axis of the third coil group 613 is parallel to the Z axis.

[0050] In the Z direction, a gap larger than the coil 71 is formed between the X stage 23 and the Y stage 25. Each coil 71 of the third coil group 613 is located away from the upper surface of the Y stage 25 in the +Z direction. When the X stage 23 moves in the X direction, the third coil group 613 moves in the X direction together with the X stage 23.

[0051] The third magnet 633 is fixed to the upper surface of the Y stage 25 (see FIG. 1). The third magnet 633 is a permanent magnet such as a neodymium magnet, for example. The third magnet 633 is positioned away from the X stage 23 and the third coil group 613 fixed to the X stage 23 in the -Z direction.

[0052] In the third magnet 633, the N pole is directed upward (toward the X stage 23 side), and the S pole is directed downward. Note that in the third magnet 633, the N pole may be directed downward and the S pole may be directed upward (toward the X stage 23 side).

[0053] When the X stage 23 moves in the X direction, each coil 71 of the third coil group 613 passes above the third magnet 633. That is, the third magnet 633 is arranged so as to be able to face the third coil group 613 in the Z direction.

[0054] When each coil 71 of the third coil group 613 approaches or separates from the third magnet 633, the magnetic flux from the third magnet 633 passing through each coil 71 changes. As a result, an induced electromotive force is generated in each coil 71 of the third coil group 613. The induced electromotive force generated in each coil 71 of the third coil group 613 is measured by an electromotive force measuring device 65 (see FIG. 4), respectively.

[0055] FIG. 4 is a block diagram showing the configuration of the control unit 9 shown in FIG. 1. The control unit 9 includes a processor such as a CPU (Central Processing Unit) and a storage unit 90. The storage unit 90 is electrically connected to the processor. The storage unit 90 includes a main storage device such as a RAM (Random Access Memory) and an auxiliary storage device such as a hard disk. The storage unit 90 stores a program P. The program P may be provided to the control unit 9 via a magnetic medium, an optical disk such as a DVD, or a semiconductor memory such as a USB (Universal Serial Bus) flash drive. By the processor executing the program P, the control unit 9 functions as an irradiation control unit 91, a stage control unit 93, a drawing control unit 95, and a position calculation unit 97. Note that a part of the functions of the control unit 9 may be realized by a dedicated circuit (for example, an application specific integrated circuit (ASIC)).

[0056] The irradiation control unit 91 controls the light irradiation unit 53 of the exposure unit 5 to cause the light irradiation unit 53 to emit line beam light toward the exposure head 51. The stage control unit 93 controls the stage moving mechanism 3 to move the support stage 21 in the Y direction, which is the main scanning direction, and the X direction, which is the sub-scanning direction, with respect to the exposure head 51. The drawing control unit 95 controls the spatial light modulator 510 of the exposure head 51 based on the drawing recipe stored in the storage unit 90 and the position information of the support stage 21. More specifically, the drawing control unit 95 controls the drive voltage applied to each channel of the spatial light modulator 510 to modulate the line beam light by the spatial light modulator 510 so as to correspond to the drawing pattern. Thereby, pattern light corresponding to the drawing pattern is formed, and the pattern light is emitted from the exposure head 51.

[0057] The drawing recipe describes, for example, pattern data indicating the drawing pattern to be formed on the substrate W and various conditions for drawing (such as the amount of light emitted from the exposure unit 5, the moving speed of the support stage 21, etc.) in a predetermined data format. The pattern data is, for example, data obtained by rasterizing CAD data generated using CAD (Computer Aided Design), and the position information on the substrate W to be irradiated with light is recorded in pixel units. Also, for the position information of the support stage 21, the data calculated by the position calculation unit 97 is used.

[0058] The position calculation unit 97 calculates the position of the support stage 21 in the Y direction and the position in the X direction. More specifically, the position calculation unit 97 calculates the position of the Y stage 25 in the Y direction based on the induced electromotive forces of the first coil group 611 and the second coil group 612 measured by a plurality of electromotive force measuring devices 65. Also, the position calculation unit 97 measures the position of the X stage 23 in the X direction based on the induced electromotive force of the third coil group 613 measured by a plurality of electromotive force measuring devices 65.

[0059] As shown in FIG. 4, the induced electromotive forces generated in each coil 71 of the first coil group 611, the second coil group 612, and the third coil group 613 are measured by the electromotive force measuring devices 65 connected to each coil 71. The plurality of electromotive force measuring devices 65 have the same configuration. The electromotive force measuring device 65 is connected to both ends of the corresponding coil 71 and measures the dielectric electromotive force (voltage) generated in the coil 71. Specifically, the electromotive force measuring device 65 includes a voltmeter that measures the voltage of the coil 71 and an AD converter that converts the voltage measured by the voltmeter into digital data. Also, each electromotive force measuring device 65 inputs data indicating the measured electromotive force to the control unit 9 via an interface.

[0060] As shown in FIG. 4, each electromotive force measuring device 65 has a filter 651. The filter 651 is provided, for example, to remove noise (high-frequency components) generated from a motor of the stage moving mechanism 3 or the like. Each electromotive force measuring device 65 inputs a signal from which the noise component has been removed by the filter 651 to the control unit 9. Thereby, since the influence of noise from the motor of the stage moving mechanism 3 or the like can be reduced, the calculation accuracy of the position of the support stage 21 by the position calculation unit 97 can be improved.

[0061] In the exposure apparatus 100, when exposing the substrate W, the main scanning movement for moving the substrate W supported by the support stage 21 in the Y direction (main scanning direction) is performed by moving the Y stage 25 in the Y direction. Then, the exposure head 51 irradiates the substrate W moving in the Y direction with pattern light. Further, after the main scanning movement, the sub-scanning movement for moving the substrate W is performed by moving the X stage 23 in one direction in the X direction by the width of the pattern light. The exposure apparatus 100 exposes the photosensitive layer of the substrate W by repeating such main scanning movement and sub-scanning movement.

[0062] FIGS. 5 to 7 are diagrams conceptually showing the time change of the induced electromotive force generated in the first coil group 611. FIG. 5 shows the initial state. FIG. 6 shows a state in which a time t1 has elapsed from the state shown in FIG. 5, and shows a state in which a coil 71 (referred to as “coil 1”) located first from the +Y side in the first coil group 611 passes directly above the first magnet 631. FIG. 7 shows a state in which a time t2 has elapsed from the state shown in FIG. 5, and shows a state in which a second coil 71 (referred to as “coil 2”) located second from the +Y side in the first coil group 611 passes directly above the first magnet 631. In FIGS. 5 to 7, for convenience of illustration, the voltage levels of coil 1 and coil 2 are shown shifted vertically.

[0063] In the initial state shown in FIG. 5, since the Y stage 25 is away from the first magnet 631 in the -Y direction, the coils 1 and 2 are not affected by the magnetic flux generated from the first magnet 631. Therefore, the induced electromotive force is at the base level. Then, as shown in FIG. 6, as the Y stage 25 moves in the +Y direction, the magnetic flux density passing through the coil 1 increases. As a result, an induced electromotive force V 1 is generated in the direction that hinders the change in the magnetic flux density in the coil 1. After the coil 1 passes through the first magnet 631, since the magnetic flux density passing through the coil 1 decreases, an induced electromotive force is generated in the opposite direction.

[0064] In the state shown in FIG. 7, an induced electromotive force V 2 is generated in the coil 2. Between time t 1 and time t 2 , the coil 1 has passed through the magnetic flux from the first coil group 611. Therefore, at the time when the time t2 has elapsed, the induced electromotive force of the coil 1 becomes the base level.

[0065] In this way, by measuring the induced electromotive force generated in each coil 71 of the first coil group 611, the position of the Y stage 25 in the Y direction, that is, the position of the support stage 21 in the Y direction can be measured. Also, from the known distance d 1 between the coils 71 and the time (t 2 -t 1 ) from the time when the induced electromotive force of the coil 1 becomes V1 to the time when the induced electromotive force of the coil 2 becomes V2, the moving speed of the Y stage 25, that is, the moving speed of the support stage 21 can be calculated. Note that the sampling speed of the AD converter of the electromotive force measuring device 65 is preferably set to a value suitable for the moving speed of the Y stage 25.

[0066] As described above, the exposure apparatus 100 as a substrate processing apparatus includes a stage 2, a stage moving mechanism 3, a first coil group 611 including a plurality of first coils 71, a first magnet 631, an electromotive force measuring device 65, and a position calculation unit 97. The stage 2 supports a substrate W. The stage moving mechanism 3 moves the stage 2 in the Y direction as the first direction. The first coil group 611 is fixed to the Y stage 25 of the stage 2. The plurality of coils 71 of the first coil group 611 are arranged at intervals in the Y direction. The first magnet 631 is fixed at a position away from the Y stage 25 of the stage 2 and at a position where it can face the first coil group 611. The electromotive force measuring device 65 measures the induced electromotive force generated in the first coil group 611 by the magnetic flux from the first magnet 631. The position calculation unit 97 calculates the position of the Y stage 25 in the Y direction based on the induced electromotive force measured by the electromotive force measuring device 65.

[0067] According to this configuration, an induced electromotive force is generated in each coil 71 as each coil 71 passes near the first magnet 631. Therefore, based on the measured induced electromotive force, the position of the Y stage 25 in the Y direction can be measured. Also, since it is not affected by air fluctuations like a laser length measuring system, the position of the stage 2 in the Y direction can be measured with high accuracy and at low cost.

[0068] Further, the exposure apparatus 100 further includes a second coil group 612 including a plurality of second coils 71 and a second magnet 632. The second coil group 612 is fixed to the Y stage 25. The plurality of coils 71 of the second coil group 612 are arranged at intervals in the Y direction. The second coil group 612 is fixed at a position away from the Y stage 25 and at a position where it can face the second coil group 612. The second coil group 612 is located away from the first coil group 611 in the X direction as the second direction. The electromotive force measuring device 65 can measure the induced electromotive force generated in the second coil group 612 by the magnetic flux from the second magnet 632.

[0069] According to this configuration, the rotation angle and rotation direction of the Y stage 25 about the Z axis intersecting the Y direction and the X direction can be detected.

[0070] Further, the exposure apparatus 100 further includes a third coil group 613 including a plurality of third coils 71 and a third magnet 633. The third coil group 613 is fixed to the X stage 23 of the stage 2. The plurality of coils 71 of the third coil group 613 are arranged at intervals in the X direction as the third direction. The third magnet 633 is fixed at a position away from the X stage 23 of the stage 2 and at a position where it can face the third coil group 613. The stage moving mechanism 3 can move the X stage 23 of the stage 2 in the X direction. The electromotive force measuring device 65 can measure the induced electromotive force generated in the third coil group 613 by the magnetic flux from the third magnet 633.

[0071] According to this configuration, the position of the X stage 23 in the X direction can be detected.

[0072] Further, the exposure apparatus 100 further includes an exposure head 51 capable of exposing a substrate W supported by a support stage 21 of a stage 2 that moves in the Y direction by a stage moving mechanism 3.

[0073] According to this configuration, since the position of the support stage 21 in the Y direction can be accurately measured, the substrate can be accurately exposed.

[0074] The Y stage 25 is preferably a non-conductive member such as a non-metal. When the Y stage 25 is a conductive member, an induced electromotive force is generated in the Y stage 25 by the magnetic flux from the first magnet 631 or the second magnet 632. Then, due to the induced electromotive force of the Y stage 25, the induced electromotive force generated in each coil 71 may change, resulting in a possible decrease in the position measurement accuracy. Therefore, by making the Y stage 25 a non-conductive member, the generation of the induced electromotive force in the Y stage 25 can be suppressed, so that the position measurement accuracy of the Y stage 25 can be improved. Similarly to the Y stage 25, the X stage 23 is also preferably a non-conductive member. By making the X stage 23 a non-conductive member, the generation of the induced electromotive force in the X stage 23 by the magnetic flux from the third magnet 633 can be suppressed. For this reason, the position measurement accuracy of the X stage 23 can be improved.

[0075] FIG. 8 is a top view schematically showing the Y stage 25 that moves while tilted. In FIG. 8, the Y stage 25 moving in the +Y direction is illustrated. Also, in FIG. 8, the Y stage 25 is tilted such that, among the +Y side surfaces of the Y stage 25, the -X side end portion is located in front of (+Y side) the +X side end portion. That is, the Y stage 25 is rotated by a predetermined angle clockwise in a top view. In the present embodiment, it is possible to detect the rotation angle and the rotation direction of the Y stage 25 based on the induced electromotive forces generated in the first coil group 611 and the second coil group 612.

[0076] A plurality of coils 71 in the first coil group 611 are referred to as coil 1, coil 2, ···, coil N in order from the coil 71 located on the most +Y side. In the state shown in FIG. 8, when the Y stage 25 moves at a constant speed in the +Y direction, in the X direction, coil 1 is closest to the first magnet 631 and coil N is the farthest. For this reason, the amount of magnetic flux passing through each coil decreases in the order of coil 1, coil 2, ···, coil N, and thus the magnitude of the induced electromotive force also decreases in this order. Therefore, by obtaining in advance the correlation between the rotation angle of the Y stage 25 and the magnitude of the induced electromotive force generated in the first coil group 611, the rotation angle of the Y stage 25 can be calculated from the actually measured induced electromotive force. Similar to the first coil group 611, the rotation angle can be calculated based on the induced electromotive force generated in the second coil group 612.

[0077] Note that the correlation between the rotation angle of the Y stage 25 and the change in the magnitude of the induced electromotive force may be stored in the storage unit 90 of the control unit 9. When the Y stage 25 is actually moved in the Y direction, the position calculation unit 97 may calculate the inclination of the Y stage 25 based on the measured induced electromotive force and the correlation stored in the storage unit 90. Then, the drawing control unit 95 may correct the exposure position based on the calculated rotation amount.

[0078] Also, regarding the rotation direction of the Y stage 25, it is possible to detect based on the timing of the induced electromotive force generated in the first coil group 611 and the second coil group 612. For example, as shown in FIG. 8, assume that the Y stage 25 is located on the -Y side of the first magnet 631 and the second magnet 632, and the Y stage 25 moves in the +Y direction. As shown in FIG. 8, when the Y stage 25 rotates clockwise, the induced electromotive force is generated earlier in the leading coil 71 of the first coil group 611 than in the leading coil 71 of the second coil group 612. On the other hand, when the Y stage 25 rotates counterclockwise, the induced electromotive force is generated earlier in the leading coil 71 of the second coil group 612 than in the leading coil 71 of the first coil group 611. Thus, it is possible to specify the rotation direction based on the positional relationship of each coil 71 in the first coil group 611 and the second coil group 612, and the timing of the induced electromotive force generated in each coil 71.

[0079] <2. Second Embodiment> Next, the second embodiment will be described. In the following description, elements having the same functions as the elements already described may be denoted by the same reference numerals or reference numerals with added alphabetic characters, and detailed descriptions may be omitted.

[0080] In the first embodiment, the first magnet 631, the second magnet 632, and the third magnet 633 are permanent magnets, but these may be electromagnets. FIG. 9 is a diagram showing the Y stage 25, the first coil group 611, and the first magnet 631A according to the second embodiment. The first magnet 631A is an electromagnet. The first magnet 631A is a coil wound in a spiral or spiral shape. The coil axis of the first magnet 631A extends in the Z direction. An AC power source (not shown) is connected to the first magnet 631A. Even when the first magnet 631A is an electromagnet, the position calculation unit 97 can calculate the position of the Y stage 25 from the induced electromotive force generated in each coil 71 in the same manner as in the case of a permanent magnet.

[0081] Since the AC voltage applied to the first magnet 631A has frequency components, even when the Y stage 25 is stationary, the magnetic flux passing through the receiving coil 71 changes, and an induced electromotive force is generated in the coil 71. Therefore, the correlation between the distance between a specific coil 71 fixed to the Y stage 25 and the first magnet 631A and the magnitude of the induced electromotive force generated in the specific coil 71 when an AC voltage is applied to the first magnet 631A may be obtained in advance by measurement or simulation, and the obtained correlation may be stored in the storage unit 90. Then, the position calculation unit 97 may specify the position of the Y stage 25 from the induced electromotive force generated in each coil 71 when an AC voltage is applied to the first magnet 631A and the correlation stored in the storage unit 90. Also, even when the third magnet 633 is an electromagnet, the position calculation unit 97 may specify the position of the X stage 23 in the X direction from the induced electromotive force generated in each coil 71 of the third coil group 613 when an AC voltage is applied to the third magnet 633.

[0082] Note that when an AC voltage is applied, as shown in FIG. 9, the frequency component of the AC voltage is added to the change in the induced electromotive force. For this reason, it may be difficult to detect the actual base level and peak of the induced electromotive force of the coil 71. For this reason, the electromotive force measuring device 65 may have a filter capable of removing the frequency component of the AC voltage.

[0083] Also, the voltage applied to the first magnet 631A is not limited to an AC voltage, and a DC voltage may be applied. By turning on and off the DC voltage for the first magnet 631A, an induced electromotive force can be generated in the coil 71 close to the first magnet 631A. Therefore, it is possible to specify the position of the Y stage 25 from the position of the coil 71 where the induced electromotive force is generated and the generated induced electromotive force.

[0084] <3. Third Embodiment>

[0085] In the above-described first embodiment, the first coil group 611 is fixed to the bottom surface of the Y stage 25. However, the first coil group 611 may be fixed at a location other than the bottom surface of the Y stage 25.

[0086] FIG. 10 is a side view showing the Y stage 25 and the first coil group 611 according to the third embodiment. In this embodiment, the first coil group 611 is fixed to the +X side surface of the Y stage 25. Each coil 71 of the first coil group 611 is arranged to be spiral around an axis extending in the X direction. Further, the first magnet 631 is fixed to a magnet holding portion 66 fixed to the upper surface of the base 1. The first magnet 631 is arranged away from the upper surface of the base 1 in the +Z direction, and the N pole (or S pole) of the first magnet 631 is directed in the -X direction to generate a magnetic flux in the X direction. Then, the first magnet 631 is arranged to face the first coil group 611 that moves in the Y direction together with the Y stage 25.

[0087] Even when the first coil group 611 is fixed to the side surface of the Y stage 25, an induced electromotive force corresponding to the moving speed of the Y stage 25 is generated in each coil 71 as each coil 71 passes near the first magnet 631. Therefore, the position calculation unit 97 can specify the position of the Y stage 25 based on the position of the coil 71 in the Y stage 25 where the induced electromotive force is generated and the magnitude of the generated induced electromotive force.

[0088] In addition to the side surface of the Y stage 25, the first coil group 611 may also be fixed to the bottom surface of the Y stage 25. Then, the position calculation unit 97 may calculate the position of the Y stage 25 based on the induced electromotive forces generated in both of these first coil groups 611.

[0089] Also, as shown in FIG. 10, the position measurement unit 6 may have a pair of first coil groups 611 on the side surface of the Y stage 25. The pair of first coil groups 611 are arranged at intervals in the Z direction. Further, the magnet holding portion 66 is provided with a pair of first magnets 631 arranged at intervals in the Z direction.

[0090] In this way, by having the pair of first coil groups 611, the position measurement unit 6 can detect the inclination of the Y stage 25 in the Z direction, that is, the rotation angle and the rotation direction of the Y stage 25 about the axis in the X direction. For example, as shown in FIG. 10, when the Y stage 25 rotates clockwise in a side view seen from the +X side, the induced electromotive force generated in the leading coil 71 closest to the first magnet 631 is larger than the induced electromotive force generated in the coil 71 farthest from the first magnet 631 among the pair of first coil groups 611. Also, in the case of the rotation shown in FIG. 10, the induced electromotive force is generated earlier in the upper first coil group 611 than in the lower first coil group 611. In this way, based on the magnitude of the induced electromotive force generated in the pair of first coil groups 611 and the timing at which the induced electromotive force is generated, it becomes possible to specify the rotation angle and the rotation direction of the Y stage 25 about the X axis.

[0091] Similar to the first coil group 611, the second coil group 612 may also be fixed to the side surface of the Y stage 25 (for example, the side surface on the -X side). Also, the third coil group 613 may be fixed to the side surface of the X stage 23 (for example, the side surface on the -Y side or the +Y side). And the third magnet 633 may be held by a magnet holding portion (not shown) so as to be opposed to the third coil group 613 in the Y direction. Also, on the -Y side or the +Y side surface of the X stage 23, a pair of second coil groups 612 may be provided apart in the Z direction. In this case, based on the induced electromotive force generated in the pair of second coil groups 612, it becomes possible to specify the rotation angle and the rotation direction about the axis in the Y direction.

[0092] <4. Modification Example> As described above, the embodiments have been explained, but the present invention is not limited to the above, and various modifications are possible.

[0093] In each of the above embodiments, the first coil group 611 is fixed to the Y stage 25, and the first magnet 631 is fixed at a position separated from the Y stage 25. However, the first magnet 631 may be fixed to the Y stage 25, and the first coil group 611 may be fixed at a position separated from the Y stage 25. And the first coil group 611 may be fixed at a position where it can face the first magnet 631. Specifically, the first magnet 631 may be fixed to the bottom surface of the Y stage 25, and the first coil group 611 may be fixed to the upper surface of the base 1.

[0094] Also, each coil 71 of the first coil group 611, the second coil group 612, or the third coil group 613 may have a structure wound in a helical shape instead of a flat spiral shape.

[0095] Also, instead of measuring the induced electromotive force (voltage), the electromotive force measuring device 65 may measure the current generated by the induced electromotive force.

[0096] Although the present invention has been described in detail, the above description is illustrative in all aspects and the present invention is not limited thereto. Innumerable modifications not illustrated can be assumed without departing from the scope of the present invention. Each configuration described in the above embodiments and each modification can be appropriately combined or omitted as long as they do not contradict each other.

Explanation of Reference Numerals

[0097] 1 Base 2 Stage 3 Stage Moving Mechanism 6 Position Measuring Unit 21 Support Stage 23 X Stage 25 Y Stage 51 Exposure Head 65 Electromotive Force Measuring Device 71 Coil 90 Storage Unit 97 Position Calculation Unit 100 Exposure Device 611 First Coil Group 612 Second coil group 613 Third coil group 631 First magnet 631A First magnet (electromagnet) 632 Second magnet 633 Third magnet 651 Filter W Substrate

Claims

1. A substrate processing apparatus, comprising: a stage for supporting a substrate; a stage moving mechanism for moving the stage in a first direction; a first plurality of coils fixed to the stage and arranged at intervals in the first direction; a first magnet fixed at a position away from the stage and opposed to the first plurality of coils; an electromotive force measuring device for measuring an induced electromotive force generated in the first plurality of coils by a magnetic flux from the first magnet; a position calculating unit for calculating a position of the stage in the first direction based on the induced electromotive force measured by the electromotive force measuring device. The substrate processing apparatus according to claim 1.

2. The substrate processing apparatus according to claim 1, further comprising: a second plurality of coils fixed to the stage and arranged at intervals in the first direction; a second magnet fixed at a position away from the stage and opposed to the second plurality of coils; wherein the second plurality of coils are located away from the first plurality of coils in a second direction intersecting the first direction; the electromotive force measuring device is capable of measuring an induced electromotive force generated in the second plurality of coils by a magnetic flux from the second magnet.

3. The substrate processing apparatus according to claim 1 or claim 2, further comprising: a third plurality of coils fixed to the stage and arranged at intervals in a third direction intersecting the first direction; a third magnet fixed at a position away from the stage and opposed to the third plurality of coils; wherein the stage moving mechanism is capable of moving the stage in the third direction; the electromotive force measuring device is capable of measuring an induced electromotive force generated in the third plurality of coils by a magnetic flux from the third magnet.

4. The substrate processing apparatus according to claim 1 or claim 2, wherein the first plurality of coils are fixed to a bottom surface of the stage.

5. A substrate processing apparatus, comprising: a stage for supporting a substrate; a stage moving mechanism for moving the stage in a first direction; a first magnet fixed to the stage; a first plurality of coils fixed at a position away from the stage and opposed to the first magnet and arranged at intervals in the first direction. An electromotive force measuring device that measures the induced electromotive force generated in the plurality of first coils by the magnetic flux of the first magnet; A calculation unit that calculates the position of the stage in the first direction based on the induced electromotive force measured by the electromotive force measuring device; A substrate processing apparatus comprising the same. **Claim 6** The substrate processing apparatus according to claim 1 or claim 5, wherein the first magnet is an electromagnet. **Claim 7** The substrate processing apparatus according to claim 1 or claim 5, wherein the stage is a non-conductive member. **Claim 8** The substrate processing apparatus according to claim 1 or claim 5, wherein the electromotive force measuring device has a filter capable of removing noise from the measured induced electromotive force. **Claim 9** The substrate processing apparatus according to claim 1 or claim 5, further comprising an exposure head capable of exposing the substrate supported by the stage that moves in the first direction by the stage moving mechanism. A substrate processing apparatus.

Images