JP7633045B2 - Exposure method and exposure apparatus - Google Patents

Description

This invention relates to a technique for exposing a substrate, such as a semiconductor wafer or a glass substrate, to light in order to form a pattern on the substrate.

Patent documents 1 and 2 describe an exposure device that draws a pattern extending in the main scanning direction on a substrate (photosensitive material, substrate to be exposed) by irradiating light from an exposure head onto the photosensitive material while moving a stage on which the substrate is placed in the main scanning direction. In such exposure devices, there are cases where misalignment occurs between the stage and the exposure head, making it impossible to irradiate light onto the appropriate position on the photosensitive material. Therefore, Patent documents 1 and 2 address this issue by adjusting the pattern of light irradiated from the exposure head.

Patent Document 2 also focuses on stage yawing. In particular, it has been pointed out that a method of eliminating the effects of yawing by controlling the stage position based on the results of measuring the stage yawing with a laser displacement meter poses the problem of the need to equip the device with an expensive laser displacement meter. Therefore, Patent Document 2 does not use a hardware method of controlling the stage position, but instead uses a software method of correcting the data provided to the exposure head to adjust the light pattern.

JP 2007-114468 A JP 2010-113001 A

However, there are limitations to the software methods described above in terms of reliably eliminating the effect of stage yawing on the exposure position, and it is necessary to suppress the stage yawing itself using hardware. This situation is also true for devices that expose a substrate on a fixed stage while driving an exposure head in the main scanning direction.

This invention has been made in consideration of the above problems, and aims to provide a technology that suppresses yawing of a driven object, such as a stage or exposure head, when the driven object is driven in the main scanning direction by a drive mechanism while suppressing increases in costs, and enables light to be irradiated from the exposure head to an appropriate position on a substrate placed on the stage.

The exposure method according to the present invention includes the steps of: performing a first main scanning drive in which one of the driving objects, the stage on which the substrate is placed and the exposure head that irradiates the irradiation area with light, is driven in the main scanning direction by a driving mechanism, so that the driving object moves through a first movement range in the main scanning direction and the substrate passes through the irradiation area relatively in the main scanning direction; performing a first yawing correction operation in which the driving mechanism corrects the amount of rotation of the driving object in the yaw direction during the execution of the first main scanning drive based on first yawing correction information indicating a first correction amount for correcting the amount of rotation of the driving object in the yaw direction according to the position of the driving object in the main scanning direction in the first movement range; and performing an exposure operation in which the exposure head irradiates the irradiation area with light during the execution of the first main scanning drive to expose an area extending in the main scanning direction on the substrate.

The exposure apparatus according to the present invention includes a stage on which a substrate is placed, an exposure head that irradiates light onto an irradiation range, a drive mechanism that drives one of the stage and the exposure head as a drive target in the main scanning direction, a storage unit that stores first yawing correction information indicating a first correction amount for correcting the rotation amount of the drive target in the yaw direction according to the position of the drive target in the main scanning direction in a first movement range in the main scanning direction, and a control unit that performs an exposure operation to expose an area extending in the main scanning direction on the substrate by irradiating light onto the irradiation range from the exposure head while performing a first main scanning drive in which the drive target moves through the first movement range by driving the drive mechanism in the main scanning direction and the substrate passes through the irradiation range relatively in the main scanning direction, and the control unit performs a first yawing correction operation to correct the rotation amount of the drive target in the yaw direction by the drive mechanism during the execution of the first main scanning drive based on the first yawing correction information.

In the present invention (exposure method and exposure apparatus) configured in this way, one of the driving objects, the stage and the exposure head, is driven in the main scanning direction by the driving mechanism, so that the driving object moves through a first moving range in the main scanning direction, and the substrate passes through the irradiation range relatively in the main scanning direction (first main scanning drive). Then, in parallel with the first main scanning drive, the exposure head irradiates the irradiation range with light, thereby exposing an area extending in the main scanning direction on the substrate (exposure operation). In particular, the rotation amount in the yaw direction of the driving object during the execution of the first main scanning drive is corrected by the driving mechanism based on first yawing correction information indicating a first correction amount for correcting the rotation amount in the yaw direction of the driving object according to the position in the main scanning direction of the driving object in the first moving range. (First yawing correction operation). As a result, it is possible to suppress the yawing of the driving object when the driving object, such as the stage or the exposure head, is driven in the main scanning direction by the driving mechanism while suppressing an increase in cost, and to irradiate light from the exposure head to an appropriate position on the substrate placed on the stage.

The exposure method may further include a step of performing a first correction information creation operation to create first yawing correction information based on the result of determining the amount of rotation in the yaw direction of the driven object that moves in the main scanning direction in the first movement range by the drive mechanism, and the first yawing correction operation may be configured to correct the amount of rotation in the yaw direction of the driven object based on the first yawing correction information created in the first correction information creation operation. In this configuration, the first yawing correction information is created based on the result of determining the position in the yaw direction of the driven object that moves in the main scanning direction in the first movement range by the drive mechanism, i.e., the result of determining the yawing in advance (first correction information creation operation). Then, when performing an exposure operation while performing the first main scanning drive, the yawing of the driven object can be suppressed based on the first yawing correction information created in this manner.

The exposure method may be configured so that the first correction information creation operation includes a step of attaching a yaw measuring device that uses a laser interferometer to measure the amount of rotation of the stage in the yaw direction to an exposure device equipped with a stage, an exposure head, and a driving mechanism, a step of measuring the amount of rotation in the yaw direction of the driven object that moves in a first moving range by driving the driven object in the main scanning direction by the driving mechanism using the yaw measuring device, and acquiring a correspondence between the position of the driven object in the main scanning direction and the amount of rotation in the yaw direction, and a step of creating first yaw correction information based on the result of the first yaw measurement. In this configuration, the yaw of the driven object can be easily obtained by the measurement of the laser interferometer of the yaw measuring device. Moreover, the yaw measuring device is attached to the exposure device and used when measuring the yaw. Therefore, once the yaw measurement is completed, the yaw measuring device can be removed from the exposure device. Therefore, there is no need to provide a yaw measuring device in the exposure device itself, and it is possible to suppress an increase in the cost of the exposure device.

The exposure method may also include a step of performing a second main scanning drive in which the drive mechanism drives the drive target in the main scanning direction, so that the drive target moves through a second movement range in the main scanning direction and the substrate passes through the imaging range of the camera in the main scanning direction relative to the drive target; a step of performing a second yawing correction operation in which the drive mechanism corrects the amount of rotation of the drive target in the yaw direction during the execution of the second main scanning drive based on second yawing correction information indicating a second correction amount for correcting the amount of rotation of the drive target in the yaw direction according to the position of the drive target in the main scanning direction in the second movement range; and a step of performing an alignment mark acquisition operation in which the camera captures an alignment mark image of the substrate passing through the imaging range during the execution of the second main scanning drive, and the position of the alignment mark indicated by the alignment mark image is acquired. In the exposure operation, the pattern of light irradiated from the exposure head to the substrate may be adjusted according to the position of the alignment mark acquired in the alignment mark acquisition operation.

In this configuration, the driving mechanism drives the driving target in the main scanning direction, so that the driving target moves through a second moving range in the main scanning direction, and the substrate passes through the imaging range of the camera in the main scanning direction relative to the driving target (second main scanning drive). In parallel with the second main scanning drive, the camera captures an image of the alignment mark passing through the imaging range, so that an alignment mark image is captured, and the position of the alignment mark indicated by this alignment mark image is acquired (alignment mark acquisition operation). In particular, based on second yawing correction information indicating a second correction amount for correcting the rotation amount of the driving target in the yaw direction according to the position of the driving target in the main scanning direction in the second moving range, the rotation amount of the driving target in the yaw direction during the execution of the second main scanning drive is corrected by the driving mechanism (second yawing correction operation). As a result, it is possible to accurately acquire the position of the alignment mark on the substrate by suppressing the yawing of the driving target when the driving mechanism drives the driving target, such as a stage or an exposure head, in the main scanning direction while suppressing an increase in cost.

The exposure method may further include a step of performing a second correction information creation operation to create second yawing correction information based on the result of determining the amount of rotation in the yaw direction of the driven object that moves in the main scanning direction in the second movement range by the drive mechanism, and the second yawing correction operation may be configured to correct the amount of rotation in the yaw direction of the driven object based on the second yawing correction information created in the second correction information creation operation. In this configuration, the second yawing correction information is created based on the result of determining the position in the yaw direction of the driven object that moves in the main scanning direction in the second movement range by the drive mechanism, i.e., the result of determining the yawing in advance (second correction information creation operation). Then, when performing the alignment mark acquisition operation while performing the second main scanning drive, the yawing of the driven object can be suppressed based on the second yawing correction information created in this manner.

The exposure method may be configured so that the following steps are performed in the second correction information creation operation: attaching a yaw measuring device to an exposure device equipped with a stage, an exposure head, and a drive mechanism, the yaw measuring device measures the amount of rotation of the stage in the yaw direction by a laser interferometer; measuring the amount of rotation of the drive object in the yaw direction by the drive mechanism in the main scanning direction, and performing a second yaw measurement to obtain a correspondence between the position of the drive object in the main scanning direction and the amount of rotation in the yaw direction; and creating second yaw correction information based on the result of the second yaw measurement. In this configuration, the yaw of the drive object can be easily obtained by the measurement of the laser interferometer of the yaw measuring device. Moreover, the yaw measuring device is attached to the exposure device and used when measuring the yaw. Therefore, once the yaw measurement is completed, the yaw measuring device can be removed from the exposure device. Therefore, there is no need to provide a yaw measuring device in the exposure device itself, and it is possible to suppress an increase in the cost of the exposure device.

In addition, in the alignment mark acquisition operation, the position of the driven object in the main scanning direction is detected by a position detection unit and transmitted to an imaging timing control unit that controls the timing of imaging by the camera, and the imaging timing control unit images the alignment mark by causing the camera to perform imaging at a timing according to the position of the driven object in the main scanning direction received from the position detection unit, and the exposure method may be configured so that the position detection unit and the imaging timing control unit are provided in the same integrated circuit. In such a configuration, since the position detection unit and the imaging timing control unit are provided in the same integrated circuit, the position of the driven object in the main scanning direction can be transmitted to the imaging timing control unit while suppressing communication delays from the position detection unit to the imaging timing control unit. Therefore, imaging by the camera can be performed at an appropriate timing according to the position of the driven object.

The exposure method may further include a step of detecting the position of the driven object in the main scanning direction by a position detection unit and transmitting the detected position to a correction timing control unit that controls the timing of execution of the first yawing correction operation by the driving mechanism, and the correction timing control unit causes the driving mechanism to execute the first yawing correction operation at a timing according to the position of the driven object in the main scanning direction received from the position detection unit, and the position detection unit and the correction timing control unit are provided in the same integrated circuit. In this configuration, since the position detection unit and the correction timing control unit are provided in the same integrated circuit, the position of the driven object in the main scanning direction can be transmitted to the correction timing control unit while suppressing communication delays from the position detection unit to the correction timing control unit. Therefore, the amount of rotation of the driven object in the yaw direction can be corrected at an appropriate timing according to the position of the driven object.

Meanwhile, a plurality of different exposure positions in the sub-scanning direction are set for the substrate, and a wide range can be exposed by repeating the first main scanning drive, the first yawing correction operation, and the exposure operation while changing the position of the driven object by the drive mechanism between a plurality of different sub-scanning positions in the sub-scanning direction that correspond to the plurality of exposure positions. However, when the position of the driven object (sub-scanning position) changes in the sub-scanning direction, the balance of the weight applied from the stage to the drive mechanism fluctuates. Therefore, it may be difficult to suppress the yawing of the driven object at each of the plurality of sub-scanning positions by a single first yawing correction information.

The exposure method may be configured such that the first yawing correction information is provided for each of the multiple sub-scanning positions, and in the first yawing correction operation, the position of the driven object in the sub-scanning direction is corrected based on the first yawing correction information provided for the sub-scanning position where the driven object is located. With this configuration, it is possible to suppress yawing of the driven object at each of the multiple sub-scanning positions.

Alternatively, the exposure method may be configured such that the first yawing correction information is provided for each of a plurality of different set positions in the sub-scanning direction, the plurality of set positions being fewer than the plurality of sub-scanning positions, and in the first yawing correction operation, the position of the driven object in the sub-scanning direction is corrected based on the first yawing correction information provided for the set position closest to the sub-scanning position where the driven object is located among the plurality of set positions, or by linear interpolation using the first yawing correction information provided for the set position closest to the sub-scanning position where the driven object is located and the first yawing correction information provided for the set position second closest to the sub-scanning position where the driven object is located. With such a configuration, it is possible to suppress the yawing of the driven object at each of the plurality of sub-scanning positions while suppressing the memory resources required for storing the first yawing correction information.

As described above, according to the present invention, it is possible to suppress yawing of a driven object, such as a stage or exposure head, when the driven object is driven in the main scanning direction by a drive mechanism while suppressing an increase in costs, and to irradiate light from the exposure head to an appropriate position on a substrate placed on the stage.

FIG. 1 is a front view showing a schematic configuration of an exposure apparatus according to the present invention. FIG. 2 is a block diagram showing an example of an electrical configuration of the exposure apparatus in FIG. 1 . FIG. 2 is a perspective view illustrating an example of a position measuring device that measures the position of a stage by a laser interferometer. FIG. 4 is a block diagram showing an example of a detailed configuration of a control unit that executes an alignment mark obtaining operation and an exposure operation. FIG. 4 is a diagram showing an example of a straightness correction table. FIG. 4 is a diagram showing an example of a yawing correction table. 11 is a flowchart showing an example of an alignment mark obtaining operation and an exposure operation. 7 is a side view showing a schematic diagram of the operation of the exposure apparatus executed according to the flowchart of FIG. 6. FIG. 7 is a diagram showing an example of a substrate on which the flowchart of FIG. 6 is executed; 6 is a flowchart showing an example of a method for creating a yawing correction table. 11 is a flowchart showing an example of a method for creating a straightness correction table. 11 is a diagram showing an example of an operation performed to create the straightness correction table shown in FIG. 10; 11 is a diagram showing an example of an operation performed to create the straightness correction table shown in FIG. 10; 11 is a diagram showing an example of an operation performed to create the straightness correction table shown in FIG. 10; FIG. 11 is a block diagram showing a configuration for executing another example of a method for creating a straightness correction table. FIG. 13 is a perspective view showing a configuration for executing another example of a method for creating a straightness correction table.

Figure 1 is a front view showing a schematic configuration of an exposure device according to the present invention, and Figure 2 is a block diagram showing an example of the electrical configuration of the exposure device of Figure 1. In Figure 1 and the following figures, the X direction, which is the horizontal direction, the Y direction, which is the horizontal direction perpendicular to the X direction, the Z direction, which is the vertical direction, and the rotation direction θ (yaw direction) about a rotation axis parallel to the Z direction are appropriately shown.

The exposure device 1 draws a pattern on a substrate We (substrate to be exposed) on which a layer of a photosensitive material such as resist has been formed, by irradiating the substrate We with a laser beam of a predetermined pattern. As the substrate We, various substrates such as semiconductor substrates, printed circuit boards, substrates for color filters, glass substrates for flat panel displays provided in liquid crystal display devices and plasma display devices, and substrates for optical disks can be used.

The exposure device 1 has a main body 11, which is composed of a main body frame 111 and a cover panel (not shown) attached to the main body frame 111. Various components of the exposure device 1 are arranged both inside and outside the main body 11.

The inside of the main body 11 of the exposure apparatus 1 is divided into a processing area 112 and a transfer area 113. In the processing area 112, the stage 2, the stage driving mechanism 3, the exposure unit 4, and the alignment unit 5 are mainly arranged. In addition, an illumination unit 6 that supplies illumination light to the alignment unit 5 is arranged outside the main body 11. In the transfer area 113, a transport device 7 such as a transport robot that transports the substrate We in and out of the processing area 112 is arranged. Furthermore, a control unit 8 is arranged inside the main body 11, and the control unit 8 is electrically connected to each part of the exposure apparatus 1 and controls the operation of each of these parts.

Incidentally, outside the main body 11 of the exposure apparatus 1, a cassette placement section 114 for placing a cassette C is disposed adjacent to the transfer area 113. The transport device 7 disposed in the transfer area 113 inside the main body 11 corresponding to this cassette placement section 114 removes the unprocessed substrate We contained in the cassette C placed on the cassette placement section 114 and loads it into the processing area 112, and also unloads the processed substrate We from the processing area 112 and stores it in the cassette C. The transfer of the cassette C to the cassette placement section 114 is performed by an external transport device (not shown). The loading of the unprocessed substrate We and the unloading of the processed substrate We are performed by the transport device 7 in response to instructions from the control section 8.

The stage 2 has a flat plate-like outer shape and holds the substrate We placed on its upper surface horizontally. A number of suction holes (not shown) are formed in the upper surface of the stage 2, and the substrate We placed on the stage 2 is fixed to the upper surface of the stage 2 by applying negative pressure (suction pressure) to the suction holes. The stage 2 is driven by a stage driving mechanism 3.

The stage driving mechanism 3 is an X-Y-Z-θ driving mechanism that moves the stage 2 in the Y direction (main scanning direction), X direction (sub-scanning direction), Z direction, and rotational direction θ (yaw direction). The stage driving mechanism 3 has a Y-axis robot 31, which is a single-axis robot extending in the Y direction, a table 32 driven in the Y direction by the Y-axis robot 31, an X-axis robot 33, which is a single-axis robot extending in the X direction on the upper surface of the table 32, a table 34 driven in the X direction by the X-axis robot 33, and a θ-axis robot 35 that drives the stage 2 supported on the upper surface of the table 34 in the rotational direction θ relative to the table 34.

Therefore, the stage driving mechanism 3 can drive the stage 2 in the Y direction by the Y-axis servo motor 311 of the Y-axis robot 31, drive the stage 2 in the X direction by the X-axis servo motor 331 of the X-axis robot 33, and drive the stage 2 in the rotation direction θ by the θ-axis servo motor 351 of the θ-axis robot 35. The stage driving mechanism 3 can also drive the stage 2 in the Z direction by the Z-axis robot, which is omitted in FIG. 1. The stage driving mechanism 3 moves the substrate We placed on the stage 2 by operating the Y-axis robot 31, the X-axis robot 33, the θ-axis robot 35, and the Z-axis robot in response to commands from the control unit 8.

The exposure unit 4 has an exposure head 41 arranged above the substrate We on the stage 2, and a light irradiation section 43 that irradiates the exposure head 41 with laser light. The light irradiation section 43 has a laser driver 431, a laser oscillator 432, and an illumination optical system 433. The laser driver 431 is operated to emit laser light from the laser oscillator 432, which is then irradiated to the exposure head 41 via the illumination optical system 433. The exposure head 41 modulates the laser light irradiated from the light irradiation section 43 using a spatial light modulator, and illuminates the laser light onto the substrate We moving directly below it. By exposing the substrate We to the laser light in this way, a pattern is drawn on the substrate We (exposure operation).

The alignment unit 5 has an alignment camera 51 arranged above the substrate We on the stage 2. This alignment camera 51 has a lens barrel, an objective lens, and a CCD image sensor, and captures an image of an alignment mark provided on the top surface of the substrate We that moves directly below it. The CCD image sensor provided in the alignment camera 51 is composed of, for example, an area image sensor (two-dimensional image sensor).

The lighting unit 6 is connected to the lens barrel of the alignment camera 51 via fiber 61, and supplies illumination light to the alignment camera 51. The illumination light guided by the fiber 61 extending from the lighting unit 6 is guided to the top surface of the substrate We via the lens barrel of the alignment camera 51, and the reflected light from the substrate We is incident on the CCD image sensor via the objective lens. This results in an image of the top surface of the substrate We being captured. The alignment camera 51 is electrically connected to the control unit 8, and captures the captured image in response to instructions from the control unit 8, and transmits the captured image to the control unit 8.

The control unit 8 acquires the position of the alignment mark indicated by the image captured by the alignment camera 51 (alignment mark acquisition operation). The control unit 8 also controls the exposure unit 4 based on the position of the alignment mark, thereby adjusting the pattern of the laser light irradiated from the exposure head 41 to the substrate We in the exposure operation. The control unit 8 then draws the pattern on the substrate We by irradiating the substrate We with laser light modulated according to the pattern to be drawn from the exposure head 41.

The exposure apparatus 1 is also provided with a main PC (Personal Computer) 91, which performs image processing on the alignment marks. In other words, the control unit 8 obtains from the main PC 91 the position of the alignment mark, which the main PC 91 calculates from the captured image of the alignment mark. Furthermore, a position measuring device 92 that measures the position of the stage 2 by a laser interferometer can be removably attached to the main body 11 of the exposure apparatus 1.

Figure 3 is a perspective view showing a schematic example of a position measuring device that measures the position of a stage using a laser interferometer. The stage 2 moves within a movable range Yt in the Y direction, which includes an alignment movement range Ya and an exposure movement range Ye. Here, the alignment movement range Ya is the range in which the stage 2 moves in the Y direction for the alignment mark acquisition operation, and the exposure movement range Ye is the range in which the stage 2 moves in the Y direction for the exposure operation. In this example, the alignment movement range Ya and the exposure movement range Ye partially overlap. However, they do not necessarily need to overlap.

The position measuring device 92 can measure the position of the stage 2 moving in the Y direction within the movable range Yt. The position measuring device 92 has two laser interferometers 921 and 922 and two mirrors 923 and 924 attached to the side of the stage 2 in the Y direction. The laser interferometers 921 and 922 emit laser light parallel to the Y direction, and the mirrors 923 and 924 are mirror surfaces perpendicular to the Y direction. The two laser interferometers 921 and 922 and the two mirrors 923 and 924 face each other in the Y direction. The laser interferometer 921 emits laser light toward the mirror 923 and measures the position of the stage 2 in the Y direction based on the result of detecting the laser light reflected by the mirror 923, and the laser interferometer 922 emits laser light toward the mirror 924 and measures the position of the stage 2 in the Y direction based on the result of detecting the laser light reflected by the mirror 924.

In the position measuring device 92, the Y-axis laser length measuring device 92y is composed of a laser interferometer 921, and the Y-axis laser length measuring device 92y outputs the measurement result of the laser interferometer 921 to the control unit 8 as the Y-direction position of the stage 2. In addition, the ΔY-axis laser length measuring device 92d is composed of a laser interferometer 921 and a laser interferometer 922, and the ΔY-axis laser length measuring device 92d outputs the tilt (in other words, the difference) between the Y-direction position of the stage 2 measured by the laser interferometer 921 and the Y-direction position of the stage 2 measured by the laser interferometer 922 to the control unit 8 as the amount of rotation in the rotation direction θ of the stage 2. Then, as will be described in detail later, the control unit 8 creates a yawing correction table Ty based on the result of measuring the position of the stage 2 by the position measuring device 92 (table creation operation).

Figure 4 is a block diagram showing an example of the detailed configuration of a control unit that executes the alignment mark acquisition operation and the exposure operation. The control unit 8 has an integrated circuit 81, for example an FPGA (Field Programmable Gate Array), and a control board 85, for example, composed of a CPU (Central Processing Unit) and memory.

The integrated circuit 81 has a Y-axis counter 811 that counts the output of the Y-axis encoder 312 provided on the Y-axis servo motor 311. Furthermore, the integrated circuit 81 has an imaging timing output unit 812, an exposure timing output unit 813, and an interrupt generation unit 814. The imaging timing output unit 812 provides the alignment camera 51 with imaging timing generated according to the Y-direction position of the stage 2 received from the Y-axis counter 811, and the alignment camera 51 captures an image at this imaging timing. The exposure timing output unit 813 provides the exposure head 41 with exposure timing generated according to the Y-direction position of the stage 2 indicated by the Y-axis counter 811, and the exposure head 41 performs exposure at this exposure timing. The interrupt generation unit 814 provides correction timing based on the straightness correction table Ts and the yawing correction table Ty, and the position correction of the stage 2 described later is performed at this correction timing.

The integrated circuit 81 further has a Y-axis position information output unit 817. This Y-axis position information output unit 817 receives as input the Y-direction position of the stage 2 measured by the Y-axis laser length measuring device 92y, the amount of rotation in the rotation direction θ of the stage 2 measured by the ΔY-axis laser length measuring device 92d, and the count value of the Y-axis counter 811. The Y-axis position information output unit 817 then outputs these inputs to the control board 85.

The control board 85 has an imaging timing control unit 851. This imaging timing control unit 851 stores the correspondence between the count value of the Y-axis counter 811, which indicates the position of the stage 2 in the Y direction, and the imaging timing, and the imaging timing output unit 812 of the integrated circuit 81 causes the alignment camera 51 to perform imaging at the imaging timing based on this correspondence obtained from the imaging timing control unit 851.

The control board 85 also has a Y-axis scale correction table section 852 that corrects the error in the Y-direction position of the stage 2 output by the Y-axis encoder 312. Specifically, a calibration operation for correcting the position of the stage 2 is performed in advance. In this calibration operation, while moving the stage 2 in the Y direction by the Y-axis servo motor 311, the Y-direction position of the stage 2 measured by the Y-axis laser length measuring device 92y and the count value by the Y-axis counter 811 of the output of the Y-axis encoder 312 are transmitted to the Y-axis scale correction table section 852 via the Y-axis position information output section 817, and the Y-axis scale correction table section 852 stores the error in the count value of the Y-axis encoder 312 relative to the measurement position of the Y-axis laser length measuring device 92y as a table (Y-axis scale correction table). Then, during the exposure operation, the exposure timing output section 813 of the integrated circuit 81 corrects the count value of the output of the Y-axis encoder 312 received from the Y-axis counter 811 based on the table, and generates the exposure timing by the exposure head 41.

The control board 85 also has an X-axis scale correction table section 853 and a θ-axis scale correction table section 854 that are similarly provided for the X direction and the rotation direction θ. That is, the X-axis scale correction table section 853 stores a table (X-axis scale correction table) that corrects the error between the output value of the X-axis encoder provided in the X-axis servo motor 331 and the X-direction position of the stage 2, and outputs a correction value for correcting this error. The θ-axis scale correction table section 854 stores a table (θ-axis scale correction table) that corrects the error between the output value of the θ-axis encoder provided in the θ-axis servo motor 351 and the amount of rotation in the rotation direction θ of the stage 2, and outputs a correction value for correcting this error.

Furthermore, the control board 85 has a Y-axis straightness correction table section 855 that stores a straightness correction table Ts (FIG. 5A). FIG. 5A is a diagram showing an example of the straightness correction table. In the example of FIG. 5A, the left column of the straightness correction table Ts indicates the Y-direction position of the stage 2 indicated by the Y-axis counter 811 (in other words, the count value of the Y-axis encoder 312 by the Y-axis counter 811) by one count across the movable range Yt, and the right column of the straightness correction table Ts indicates the correction amount (X-direction correction amount) for correcting the position of the stage 2 in the X direction. In other words, the straightness correction table Ts indicates the correspondence between the Y-direction position of the stage 2 indicated by the Y-axis counter 811 and the correction amount of the position of the stage 2 in the X direction. Therefore, the Y-axis straightness correction table section 855 drives the stage 2 in the X direction by the stage driving mechanism 3 by the correction amount indicated by the straightness correction table Ts in correspondence with the Y-direction position of the stage 2. This ensures the straightness of the stage 2 moving in the Y direction. As described below, the straightness correction table Ts is created by the cooperation of the straightness correction table creation unit 856 of the control board 85 and the CPU 911 of the main PC 91.

In this way, the control board 85 is provided with an X-axis scale correction table section 853 and a Y-axis straightness correction table section 855 as a function for correcting the position of the stage 2 in the X direction. Therefore, the control board 85 is provided with an X-axis movement amount calculation section 857 that combines the correction amounts of both correction tables 853 and 855. In other words, the X-axis movement amount calculation section 857 outputs a total correction amount obtained by adding together the correction amount output by the X-axis scale correction table section 853 and the correction amount output by the Y-axis straightness correction table section 855 to the X-axis servo motor 331, and the X-axis servo motor 331 drives the stage 2 in the X direction by the total correction amount.

The control board 85 also has an XY yaw correction table section 858 that stores a yaw correction table Ty (FIG. 5B). FIG. 5B is a diagram showing an example of the yaw correction table. In the example of FIG. 5B, the left column of the yaw correction table Ty indicates the Y-direction position of the stage 2 indicated by the Y-axis counter 811 (in other words, the count value of the Y-axis encoder 312 by the Y-axis counter 811) by one count across the movable range Yt, and the right column of the yaw correction table Ty indicates the correction amount (θ-direction correction amount) for correcting the position of the stage 2 in the rotation direction θ. In other words, the yaw correction table Ty indicates the correspondence between the Y-direction position of the stage 2 indicated by the Y-axis counter 811 and the correction amount of the position of the stage 2 in the rotation direction θ. Therefore, the XY yaw correction table section 858 drives the stage 2 in the rotation direction θ by the stage driving mechanism 3 by the correction amount indicated by the yaw correction table Ty in correspondence with the Y-direction position of the stage 2. This makes it possible to suppress yawing of the stage 2 moving in the Y direction. As described below, the yawing correction table Ty is created by the XY yawing correction table unit 858.

In this way, the control board 85 is provided with a θ-axis scale correction table section 854 and an XY yawing correction table section 858 as a function for correcting the position of the stage 2 in the rotation direction θ. Therefore, the control board 85 is provided with a θ-axis movement amount calculation section 859 that combines the correction amounts of both correction tables 854 and 858. In other words, the θ-axis movement amount calculation section 859 outputs a total correction amount obtained by adding together the correction amount output by the θ-axis scale correction table section 854 and the correction amount output by the XY yawing correction table section 858 to the θ-axis servo motor 351, and the θ-axis servo motor 351 drives the stage 2 in the rotation direction θ by the total correction amount.

Figure 6 is a flowchart showing an example of an alignment mark acquisition operation and an exposure operation, Figure 7 is a side view showing the operation of an exposure apparatus executed according to the flowchart of Figure 6, and Figure 8 is a diagram showing an example of a substrate on which the flowchart of Figure 6 is executed.

During execution of the flowchart shown in FIG. 6, the Y-axis straightness correction table unit 855 performs position correction (straightness correction) of the stage 2, and the XY yaw correction table unit 858 performs position correction (yaw correction) of the stage 2. As described above, the execution timing of these position corrections is controlled by the interrupt generation unit 814. Specifically, each time the Y-axis counter 811 counts a predetermined number of counts (for example, 10), the interrupt generation unit 814 sends an execution command to the X-axis movement amount calculation unit 857 and the θ-axis movement amount calculation unit 859, and the X-axis movement amount calculation unit 857 and the θ-axis movement amount calculation unit 859 perform the position corrections they are responsible for each time they receive an execution command. In this way, the position correction of the stage 2 is not performed for each count. However, the position correction of the stage 2 may be performed for each count.

In step S101, the stage driving mechanism 3 starts driving the stage 2 in the Y direction. This causes the stage 2 to move through the alignment movement range Ya, and the substrate We placed on the stage 2 passes through the imaging range Rc (FIG. 7) of the alignment camera 51 (step S102). On the other hand, as shown in FIG. 8, the substrate We has an alignment mark Ma attached thereto. Therefore, the alignment camera 51 captures an image of the alignment mark Ma moving through the imaging range Rc to obtain an alignment mark image Ia (step S103, alignment mark acquisition operation). In this way, the alignment mark image Ia is captured between the time when the tip of the stage 2 reaches one end of the alignment movement range Ya ("at the start of alignment mark acquisition" in FIG. 7) and the time when the tip of the stage 2 reaches the other end of the alignment movement range Ya ("at the end of alignment mark acquisition" in FIG. 7).

Furthermore, in the alignment mark acquisition operation (step S103), the alignment mark image Ia is transmitted from the alignment camera 51 to the main PC 91 (Figure 4). The CPU 911 of the main PC 91 extracts the position of the alignment mark Ma by performing image processing on the alignment mark image Ia, and transmits it to the control unit 8. In this way, the control unit 8 acquires the position of the alignment mark Ma from the CPU 911 (alignment mark acquisition operation). Then, the control unit 8 adjusts the pattern of light to be irradiated to the substrate We based on the position of the alignment mark Ma acquired by the alignment mark acquisition operation.

Also, shortly before the stage 2 reaches the other end of the alignment movement range Ya, the stage 2 reaches one end of the exposure movement range Ye. As a result, the stage 2 moves through the exposure movement range Ye, and the substrate We placed on the stage 2 passes through the irradiation range Re (FIG. 7) of the exposure head 41 (step S104). Also, in parallel with the passage of the substrate We through the irradiation range Re, the exposure head 41 irradiates the irradiation range Re with laser light to expose the stripe region Rs extending in the Y direction on the substrate We (exposure operation). At this time, the laser light irradiated to the irradiation range Re is adjusted based on the position of the alignment mark Ma, as described above. In this way, the exposure operation is performed between the time when the tip of the stage 2 reaches one end of the exposure movement range Ye ("at the start of the exposure operation" in FIG. 7) and the time when the tip of the stage 2 reaches the other end of the exposure movement range Ye ("at the end of the exposure operation" in FIG. 7).

When the exposure operation is completed, the stage driving mechanism 3 stops the movement of the stage 2 in the Y direction (step S106). As shown in FIG. 8, a plurality of stripe regions Rs arranged in the Y direction are set on the substrate We, and laser light is irradiated to one stripe region Rs in one exposure operation. Therefore, in step S107, it is confirmed whether the exposure operation has been performed on all stripe regions Rs. If there is a stripe region Rs for which the exposure operation has not been performed (i.e., unexposed), the stage driving mechanism 3 drives the stage 2 in the X direction to position the irradiation range Re of the exposure head 41 in the unexposed stripe region Rs (step S108), and repeats steps S104 to S106. However, the direction in which the stage 2 passes through the exposure movement range Ye in this exposure operation is opposite to that of the previous exposure operation. In this way, by performing multiple exposure operations while moving the stage 2 back and forth in the Y direction, all stripe regions Rs can be exposed.

Figure 9 is a flow chart showing an example of a method for creating a yawing correction table. In step S201, an operator or a work robot attaches the position measuring device 92 to the main body 11 of the exposure apparatus 1. In step S202, the stage driving mechanism 3 starts driving the stage 2 in the Y direction. This causes the stage 2 to move through a movable range Yt including the alignment movement range Ya and the exposure movement range Ye. At this stage, the straightness correction table Ts and the yawing correction table Ty have not been created, so straightness correction and yawing correction cannot be performed. Therefore, while the Y-axis servo motor 311 of the stage driving mechanism 3 is operating, the X-axis servo motor 331 and the θ-axis servo motor 351 are stopped, and straightness correction and yawing correction are not functioning.

In this way, while the Y-axis servo motor 311 is driving the stage 2 in the Y direction, the XY yawing correction table unit 858 associates the output value from the ΔY-axis laser length measuring device 92d (amount of rotation in the direction of rotation θ) with the output value from the Y-axis counter 811 (position in the Y direction) and acquires them for each count of the Y-axis counter 811 (step S204). These are acquired via the Y-axis position information output unit 817. This provides a yawing measurement result that indicates the correspondence between the count value of the Y-axis counter 811 and the amount of rotation in the direction of rotation θ of the stage 2 located at the position indicated by that count value.

When yawing measurement results have been obtained for the entire movable range Yt, the movement of the stage 2 in the Y direction stops (step S205). Then, the XY yawing correction table unit 858 calculates the error between the reference rotation amount θ0 in the rotation direction θ and the measured rotation amount of the stage 2 in the rotation direction θ, and creates and stores the yawing correction table Ty by calculating the correction amount for the rotation direction θ required to eliminate this error (step S206).

Incidentally, a process may be provided in which the position measuring device 92 is removed from the main body 11 of the exposure apparatus 1 by an operator or a work robot after the movement of the stage 2 in the Y direction has stopped. On the other hand, if the straightness correction table creation operation described with reference to FIG. 10 etc. is to be performed subsequently, this process does not need to be performed.

Figure 10 is a flowchart showing an example of a method for creating a straightness correction table, and Figures 11A, 11B, and 12 are diagrams showing the operations executed in creating the straightness correction table of Figure 10. If the position measuring device 92 is not attached to the main body 11 of the exposure apparatus 1 before the start of the flowchart of Figure 10, the position measuring device 92 is attached to the main body 11 by an operator or a work robot.

In step S301, the test substrate Wt is placed on the stage 2. The test substrate Wt is, for example, a glass substrate, and on the upper surface of the test substrate Wt, as shown in FIG. 12, a plurality of test marks Mt are arranged in the Y direction. The positional relationship of each test mark Mt in the X direction is measured in advance and stored in the straightness correction table creation unit 856. Here, each test mark Mt is provided at the same position in the X direction, and the plurality of test marks Mt are arranged in parallel in the Y direction. Furthermore, a photosensitive material such as resist is applied to the upper surface of the glass substrate of the test substrate Wt, and the alignment camera 51 can capture an image of the test marks Mt through this photosensitive material.

In step S302, the stage driving mechanism 3 starts driving the stage 2 in the Y direction. This causes the stage 2 to move through the alignment movement range Ya, and the test substrate Wt passes through the imaging range Rc of the alignment camera 51. At this stage, the straightness correction table Ts has not been created, so straightness correction cannot be performed. On the other hand, the yawing correction table Ty has been created, so yawing correction can be performed. Therefore, while the Y-axis servo motor 311 of the stage driving mechanism 3 drives the stage 2 in the Y direction, the θ-axis servo motor 351 drives the stage 2 in the rotation direction θ based on the yawing correction table Ty to perform yawing correction. On the other hand, the X-axis servo motor 331 is stopped, so straightness correction is not performed.

In step S304, the alignment camera 51 captures an image of the test mark Mt moving in the imaging range Rc to obtain a test mark image It (FIG. 12). In this way, the test mark image It is captured between the time when the leading edge of the stage 2 reaches one end of the alignment movement range Ya ("Test mark acquisition start time" in FIG. 11A) and the time when the leading edge of the stage 2 reaches the other end of the alignment movement range Ya ("Test mark acquisition end time" in FIG. 11A).

Furthermore, the test mark image It is transmitted from the alignment camera 51 to the main PC 91 in association with the count value of the Y-axis counter 811 when the test mark image It was captured (FIG. 4). The CPU 911 of the main PC 91 extracts the X-direction position of the test mark Mt by performing image processing on the test mark image It. Then, the X-direction position of the test mark Mt is correlated with the count value of the Y-axis counter 811 when the test mark Mt was captured, and transmitted from the main PC 91 to the straightness correction table creation unit 856 of the control board 85.

This makes it possible to measure the X-direction position of the test mark Mt, i.e., the X-direction position of the stage 2, for the count values across the entire alignment movement range Ya (step S305). The straightness correction table creation unit 856 then determines the error between the reference position X0 in the X direction and the measured X-direction position of the stage 2 for each count value, and determines the amount of correction in the X direction required to eliminate such error, thereby creating a straightness correction table Ts for the alignment movement range Ya and storing it in the Y-axis straightness correction table unit 855 (step S306).

Furthermore, as the stage 2 is driven in the Y direction, the stage 2 moves through the exposure movement range Ye, and the test substrate Wt passes through the irradiation range Re of the exposure head 41 (step S307). In step S308, the exposure head 41 irradiates the test substrate Wt moving through the irradiation range Re with a light beam, thereby drawing an exposure mark Me on each test mark Mt on the test substrate Wt (FIG. 12). In this way, the exposure operation is performed between when the tip of the stage 2 reaches one end of the exposure movement range Ye ("exposure operation start time" in FIG. 11A) and when the tip of the stage 2 reaches the other end of the exposure movement range Ye ("exposure operation end time" in FIG. 11A).

The stage driving mechanism 3 stops the movement of the stage 2 in the Y direction in step S309 (step S309), and moves the stage 2 to the start point (one end) of the alignment movement range Ya in step S310 ("At the start of exposure mark acquisition" in FIG. 11B). Next, the Y-axis straightness correction table unit 855 turns on straightness correction using the straightness correction table Ts for the alignment movement range Ya created in step S306 (step S311).

In step S312, the stage driving mechanism 3 starts driving the stage 2 in the Y direction. This causes the stage 2 to move through the alignment movement range Ya, and the test substrate Wt passes through the imaging range Rc of the alignment camera 51. At this time, straightness correction is performed on the stage 2 based on the straightness correction table Ts created in step S306.

In step S314, the alignment camera 51 captures the exposure mark Me moving within the imaging range Rc to obtain an exposure mark image Ie (FIG. 12). Thus, the exposure mark image Ie is captured between the time when the leading edge of the stage 2 reaches one end of the alignment movement range Ya ("exposure mark acquisition start time" in FIG. 11B) and the time when the leading edge of the stage 2 reaches the other end of the alignment movement range Ya ("exposure mark acquisition end time" in FIG. 11B).

Furthermore, the exposure mark image Ie is transmitted from the alignment camera 51 to the main PC 91 in association with the count value of the Y-axis counter 811 when the exposure mark image Ie was captured (FIG. 4). The CPU 911 of the main PC 91 extracts the X-direction position of the exposure mark Me by performing image processing on the exposure mark image Ie. Then, the X-direction position of the exposure mark Me is associated with the count value of the Y-axis counter 811 when the exposure mark Me was captured, and transmitted from the main PC 91 to the straightness correction table creation unit 856 of the control board 85.

As described above, the exposure head 41 irradiates a light beam onto the test substrate Wt placed on the stage 2 passing through the exposure movement range Ye, thereby drawing the exposure mark Me. In addition, when the stage 2 passes through the alignment movement range Ya while a straightness correction is being performed on the stage 2, the X-direction position of the exposure mark Me is obtained based on the image of the exposure mark Me captured by the alignment camera 51. The X-direction position of each exposure mark Me obtained in this manner represents the straightness of the stage 2 within the exposure movement range Ye.

This allows the X-direction position of the exposure mark Me to be measured for the count values across the entire exposure movement range Ye (step S315). The straightness correction table creation unit 856 then determines the error between the reference position X0 in the X direction and the measured X-direction position of the stage 2 for each count value, and determines the amount of correction in the X direction required to eliminate the error, thereby creating a straightness correction table Ts for the exposure movement range Ye and storing it in the Y-axis straightness correction table unit 855 (step S316). As described above, the alignment movement range Ya and the exposure movement range Ye partially overlap. For this overlapping portion, it is sufficient to select and use either the data determined in step S306 or the data determined in step S316.

As described above, by driving the stage 2 (drive target) in the Y direction (main scanning direction) by the stage drive mechanism 3 (drive mechanism), the stage 2 moves in the exposure movement range Ye (first movement range) in the Y direction, and the substrate We passes through the irradiation range Re in the Y direction (step S104 (first main scanning drive)). Then, in parallel with the first main scanning drive (step S104), the exposure head 41 irradiates the irradiation range Re with light, thereby exposing the stripe region Rs extending in the Y direction on the substrate We (step S105 (exposure operation)). In particular, based on the yawing correction table Ty (first yawing correction information) indicating the θ direction correction amount (first correction amount) for correcting the rotation amount in the rotation direction θ (yaw direction) of the stage 2 according to the position of the stage 2 in the Y direction in the exposure movement range Ye, the rotation amount in the rotation direction θ of the stage 2 during the first main scanning drive is corrected by the stage drive mechanism 3 (first yawing correction operation). As a result, it is possible to suppress yawing of the stage 2 when the stage 2 is driven in the Y direction by the stage driving mechanism 3 while suppressing an increase in costs, and to irradiate light from the exposure head 41 to an appropriate position on the substrate We placed on the stage 2.

In addition, a first correction information creation operation (steps S201 to S206) is performed to create a yawing correction table Ty based on the result of determining the amount of rotation in the rotation direction θ of the stage 2 moving in the Y direction in the exposure movement range Ye by the stage drive mechanism 3. Then, in the yawing correction (first yawing correction operation) performed in parallel with the movement of the exposure movement range Ye of the stage 2 in step S104 (first main scanning drive), the amount of rotation in the rotation direction θ of the stage 2 is corrected based on the yawing correction table Ty created in the first correction information creation operation (steps S201 to S206). In other words, the yawing correction table Ty is created (steps S201 to S206) based on the result of determining the position in the rotation direction θ of the stage 2 moving in the Y direction in the exposure movement range Ye by the stage drive mechanism 3, that is, the result of determining the yawing in advance. Then, when performing the exposure operation (step S105) while performing the movement of the exposure movement range Ye of the stage 2 in step S104 (first main scanning drive), the yawing of the stage 2 can be suppressed based on the yawing correction table Ty thus created.

In addition, a step (step S201) is provided for attaching a position measuring device 92 (yawing measuring device) to the exposure apparatus 1, which measures the amount of rotation of the stage 2 in the rotation direction θ by a laser interferometer. Then, the stage 2 is driven in the Y direction by the stage driving mechanism 3, and the amount of rotation of the stage 2 in the rotation direction θ is measured by the position measuring device 92, which moves through the exposure movement range Ye. A first yawing measurement is performed (step S204), which corresponds and obtains the position of the stage 2 in the Y direction and the amount of rotation in the rotation direction θ, and a yawing correction table Ty (first yawing correction information) is created based on the result of the first yawing measurement (step S206). In this configuration, the yawing of the stage 2 can be easily obtained by the measurement of the laser interferometer of the position measuring device 92. Moreover, the position measuring device 92 is attached to the exposure apparatus 1 and used when measuring the yawing. Therefore, once the measurement of the yawing is completed, the position measuring device 92 can be removed from the exposure apparatus 1. Therefore, there is no need to equip the exposure apparatus 1 itself with a position measuring device 92, which makes it possible to prevent an increase in the cost of the exposure apparatus 1.

In addition, by driving the stage 2 in the Y direction by the stage driving mechanism 3, the stage 2 moves through the alignment movement range Ya (second movement range) in the Y direction, and the substrate We passes through the imaging range Rc of the alignment camera 51 in the Y direction (step S102 (second main scanning drive)).Then, in parallel with the second main scanning drive (step S102), the alignment camera 51 captures an image of the alignment mark Ma passing through the imaging range Rc, thereby capturing an alignment mark image Ia, and the position of the alignment mark Ma indicated by this alignment mark image Ia is acquired (step S103, alignment mark acquisition operation). In particular, the amount of rotation of the stage 2 in the rotation direction θ during execution of the second main scanning drive is corrected by the stage drive mechanism 3 based on a yawing correction table Ty (second yawing correction information) indicating a θ-direction correction amount (second correction amount) for correcting the amount of rotation of the stage 2 in the rotation direction θ according to the position of the stage 2 in the Y direction within the alignment movement range Ya (second yawing correction operation). As a result, it is possible to accurately obtain the position of the alignment mark Ma on the substrate We by suppressing yawing of the stage 2 when the stage 2 is driven in the Y direction by the stage drive mechanism 3 while suppressing an increase in costs.

A second correction information creation operation (steps S201 to S206) is also performed to create a yawing correction table Ty based on the result of determining the amount of rotation in the rotation direction θ of the stage 2 moving in the Y direction in the alignment movement range Ya by the stage drive mechanism 3. Then, in the yawing correction (second yawing correction operation) performed in parallel with the movement of the alignment movement range Ya of the stage 2 in step 102 (second main scanning drive), the amount of rotation in the rotation direction θ of the stage 2 is corrected based on the yawing correction table Ty created in the second correction information creation operation (steps S201 to S206). In other words, the yawing correction table Ty is created (steps S201 to S206) based on the result of determining the position in the rotation direction θ of the stage 2 moving in the Y direction in the alignment movement range Ya by the stage drive mechanism 3, that is, the result of determining the yawing in advance. Then, when performing the alignment mark acquisition operation (step S103) while performing the movement of the alignment movement range Ya of the stage 2 in step S102 (second main scanning drive), the yawing of the driven object can be suppressed based on the yawing correction table Ty created in this way.

In addition, a process (step S201) is provided for attaching a position measuring device 92 (yawing measuring device) that measures the amount of rotation of the stage 2 in the rotation direction θ with a laser interferometer to the exposure apparatus 1. Then, the stage 2 is driven in the Y direction by the stage driving mechanism 3, and the amount of rotation of the stage 2 in the rotation direction θ that moves through the alignment movement range Ya is measured by the position measuring device 92, and a second yawing measurement is performed (step S204) in which the position of the stage 2 in the Y direction and the amount of rotation in the rotation direction θ are associated with each other and obtained, and a yawing correction table Ty (second yawing correction information) is created based on the result of the second yawing measurement (step S206). In this configuration, the yawing of the stage 2 can be easily obtained by the measurement of the laser interferometer of the position measuring device 92. Moreover, the position measuring device 92 is attached to the exposure apparatus 1 and used when measuring the yawing. Therefore, once the measurement of the yawing is completed, the position measuring device 92 can be removed from the exposure apparatus 1. Therefore, there is no need to equip the exposure apparatus 1 itself with a position measuring device 92, which makes it possible to prevent an increase in the cost of the exposure apparatus 1.

In the alignment mark acquisition operation (step S103), the position of the stage 2 in the Y direction is detected by the Y-axis counter 811 (position detection unit) and transmitted to the imaging timing output unit 812 (imaging timing control unit) that controls the timing of imaging by the alignment camera 51 (camera). The imaging timing output unit 812 then causes the alignment camera 51 to perform imaging at a timing according to the position of the stage 2 in the Y direction received from the Y-axis counter 811, thereby imaging the alignment mark Ma. Here, the Y-axis counter 811 and the imaging timing output unit 812 are provided in the same integrated circuit 81 (FPGA). Therefore, the position of the stage 2 in the Y direction can be transmitted to the imaging timing output unit 812 while suppressing communication delays from the Y-axis counter 811 to the imaging timing output unit 812. Therefore, imaging by the alignment camera 51 can be performed at an appropriate timing according to the position of the stage 2.

The position of the stage 2 in the Y direction is detected by the Y-axis counter 811 and transmitted to an interrupt generation unit 814 (correction timing control unit) that controls the timing of execution of yawing correction (first yawing correction operation) by the stage driving mechanism 3. The interrupt generation unit 814 then causes the stage driving mechanism 3 to execute yawing correction at a timing according to the position of the stage 2 in the Y direction received from the Y-axis counter 811. Here, the Y-axis counter 811 and the interrupt generation unit 814 are provided in the same integrated circuit 81 (FPGA). Therefore, the position of the stage 2 in the Y direction can be transmitted to the interrupt generation unit 814 while suppressing communication delays from the Y-axis counter 811 to the interrupt generation unit 814. Therefore, the amount of rotation of the stage 2 in the rotation direction θ can be corrected at an appropriate timing according to the position of the stage 2.

In the embodiment described above, the exposure device 1 corresponds to an example of the "exposure device" of the present invention, the stage 2 corresponds to an example of the "stage" and "driven object" of the present invention, the stage driving mechanism 3 corresponds to an example of the "driving mechanism" of the present invention, the exposure head 41 corresponds to an example of the "exposure head" of the present invention, the control unit 8 corresponds to an example of the "control unit" and "storage unit" of the present invention, the integrated circuit 81 corresponds to an example of the "integrated circuit" of the present invention, the Y-axis counter 811 corresponds to an example of the "position detection unit" of the present invention, and the imaging timing output unit 812 corresponds to an example of the "imaging timing control unit" of the present invention. the interrupt generating unit 814 corresponds to an example of a "correction timing control unit" of the present invention, the position measuring device 92 corresponds to an example of a "yawing measuring device" of the present invention, the alignment mark Ma corresponds to an example of an "alignment mark" of the present invention, the irradiation range Re corresponds to an example of an "irradiation range" of the present invention, the yawing correction table Ty for the exposure movement range Ye corresponds to an example of "first yawing correction information" of the present invention, the straightness correction table Ts for the alignment movement range Ya corresponds to an example of "second yawing correction information" of the present invention, and the substrate We corresponds to an example of a "yawing correction information" of the present invention. the Y direction corresponds to an example of the "substrate" of the present invention, the Y direction corresponds to an example of the "main scanning direction" of the present invention, the alignment movement range Ya corresponds to an example of the "second movement range" of the present invention, the exposure movement range Ye corresponds to an example of the "first movement range" of the present invention, the rotation direction θ corresponds to an example of the "yaw direction" of the present invention, the θ direction correction amount corresponds to an example of the "first correction amount" and "second correction amount" of the present invention, step S102 corresponds to an example of the "second main scanning drive" of the present invention, step S103 corresponds to an example of the "alignment mark acquisition operation" of the present invention, and step S104 corresponds to an example of the "first main step S102 corresponds to an example of "scanning drive", step S105 corresponds to an example of "exposure operation" of the present invention, steps S201 to S206 correspond to an example of "first correction information creation operation" and "second correction information creation operation" of the present invention, step S204 corresponds to an example of "first yawing measurement" and "second yawing measurement" of the present invention, the yawing correction performed in parallel with step S102 corresponds to an example of "second yawing correction operation" of the present invention, and the yawing correction performed in parallel with step S104 corresponds to an example of "first yawing correction operation" of the present invention.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, the method of creating the straightness correction table Ts is not limited to the above-described example. Figure 13 is a block diagram showing a configuration for executing another example of the method for creating a straightness correction table, and Figure 14 is a perspective view showing a configuration for executing another example of the method for creating a straightness correction table.

In this other example, the position of the stage 2 in the X direction is measured by a laser interferometer. That is, in addition to the configuration shown in FIG. 3, this position measuring device 92 has a laser interferometer 925 attached to the side surface of the stage 2 in the X direction, and a mirror 926 extending across the movement range of the stage 2 in the Y direction. The laser interferometer 925 emits laser light parallel to the X direction, and the mirror 926 is a mirror surface perpendicular to the X direction, and the laser interferometer 925 and the mirror 926 face each other in the X direction. The laser interferometer 925 emits laser light toward the mirror 926, and measures the position of the stage 2 in the X direction based on the result of detecting the laser light reflected by the mirror 926.

The X-axis laser length measuring device 92x is composed of a laser interferometer 925, and outputs the X-direction position of the stage 2 measured by the laser interferometer 925 to the control unit 8. The control unit 8 creates a straightness correction table Ts based on the result of measuring the position of the stage 2 by the position measuring device 92.

In other words, while the stage 2 moves in the Y direction, the straightness correction table creation unit 856 of the control unit 8 associates the count value output by the Y-axis counter 811 with the X-direction position of the stage 2 output by the X-axis laser length measurement device 92x, and acquires it for each count of the Y-axis counter 811. This provides a straightness measurement result that indicates the correspondence between the count value of the Y-axis counter 811 and the X-direction position of the stage 2 located at the position indicated by the count value.

When straightness measurement results have been obtained for the entire movable range Yt, the movement of the stage 2 in the Y direction stops. Then, the straightness correction table creation unit 856 calculates the error between the reference position X0 in the X direction and the measured position of the stage 2 in the X direction, and calculates the amount of correction in the X direction required to eliminate this error, thereby creating a straightness correction table Ts and storing it in the Y-axis straightness correction table unit 855.

In other words, in this other example, in the correction information creation operation, the straightness correction table Ts is created based on the results of measuring the position in the X direction of the stage 2 that moves in the Y direction within the exposure movement range Ye using a laser interferometer. In this configuration, the straightness of the stage 2 can be easily obtained by measurement using a laser interferometer.

As shown in FIG. 8, a plurality of different stripe regions Rs (exposure positions) are set in the X direction (sub-scanning direction) for the substrate We. The entire substrate We is exposed by repeating the first main scanning drive, the first yawing correction operation, and the exposure operation while changing the position of the stage 2 by the stage driving mechanism 3 between a plurality of different sub-scanning positions in the X direction corresponding to the plurality of stripe regions Rs. However, when the position (sub-scanning position) of the stage 2 changes in the X direction, the balance of the weight applied from the stage 2 to the stage driving mechanism 3 changes. Therefore, it may be difficult to suppress the yawing of the stage 2 at each of the plurality of sub-scanning positions by a single yawing correction table Ts.

Therefore, a yawing correction table Ty may be provided for each of the multiple sub-scanning positions (in other words, multiple stripe regions Rs). Specifically, the operation of creating the above-mentioned yawing correction table Ty may be performed for each sub-scanning position while changing the position of the stage 2 at the multiple sub-scanning positions. In this configuration, when the stage 2 is located at a sub-scanning position corresponding to one of the multiple stripe regions Rs, the amount of rotation of the rotation direction θ of the stage 2 driven in the Y direction is corrected based on the yawing correction table Ty provided for that one sub-scanning position (in other words, one stripe region Rs). This makes it possible to suppress yawing of the stage 2 in the Y direction at each of the multiple sub-scanning positions.

Alternatively, instead of providing a yaw correction table Ty for each of the multiple stripe regions Rs, the number of yaw correction tables Ty may be kept smaller than the number of stripe regions Rs. Specifically, a yaw correction table Ty is provided for each of multiple different setting positions in the X direction, and the multiple setting positions are fewer than the multiple sub-scanning positions (in other words, the multiple stripe regions Rs). In such a configuration, when the stage 2 is located at one sub-scanning position corresponding to one of the multiple stripe regions Rs, the amount of rotation of the rotation direction θ of the stage 2 driven in the Y direction is corrected based on the yaw correction table Ty provided for the setting position closest to the one sub-scanning position among the multiple setting positions. Alternatively, when the stage 2 is located at a sub-scanning position corresponding to one of the multiple stripe regions Rs, the amount of rotation in the rotation direction θ of the stage 2 driven in the Y direction may be corrected by linear interpolation using the correction amounts obtained from the yawing correction table Ty provided for the set position closest to the one sub-scanning position among the multiple set positions, and the yawing correction table Ty provided for the set position second closest to the one sub-scanning position. This makes it possible to suppress the yawing of the stage 2 at each of the multiple sub-scanning positions while reducing the memory resources required to store the yawing correction table Ty.

The straightness correction table Ts can also be configured to be provided for each of multiple sub-scanning positions or set positions.

In addition, it is assumed that the straightness of the stage 2 by the X-axis robot 33 of the stage driving mechanism 3, i.e., the straightness of the stage 2 in the X direction, is not sufficiently guaranteed. In such a case, in a configuration in which the exposure operation is performed while changing the position of the stage 2 at multiple sub-scanning positions as described above to expose each of the multiple stripe regions Rs, the position of the stage 2 in the Y direction when the exposure operation starts (exposure start position) may vary between the multiple sub-scanning positions (in other words, the multiple stripe regions Rs). Therefore, based on the results of measuring in advance the variation in the exposure start position of the stage 2 between the multiple sub-scanning positions, a correction table indicating the amount of correction to eliminate the variation may be created. In such a configuration, the position of the stage 2 in the Y direction is corrected based on this correction table, so that the exposure operation can be performed on the substrate We while suppressing the variation in the exposure start position.

In addition, information for performing straightness correction may be held in the form of a formula rather than in a table format like the straightness correction table Ts. Similarly, information for performing yaw correction may be held in the form of a formula rather than in a table format like the yaw correction table Ty. The same applies to various types of information represented by other tables.

In addition, the alignment camera 51 or the exposure head 41 may be driven instead of the stage 2 to move the stage 2 relative to the alignment camera 51 and the exposure head 41.

The arrangement of each of the functional units 811-817 and 851-859 may also be interchanged between the integrated circuit 81 and the control board 85. Furthermore, the control unit 8 does not need to be configured as separate components, such as the integrated circuit 81 and the control board 85, but may be configured as an integrated unit. The main PC 91 may also be attached integrally to the exposure apparatus 1.

Furthermore, the form of the test mark Mt provided on the test substrate Wt is not limited to the example shown in FIG. 12. For example, a single straight line extending parallel to the Y direction may be provided on the test substrate Wt as the test mark Mt.

This invention is suitable for use in technical fields such as exposing substrates to light to form patterns on substrates, such as semiconductor wafers or glass substrates.

1... exposure device 2... stage (drive object)
3...Stage driving mechanism (driving mechanism)
41: Exposure head 8: Control unit (control unit, memory unit)
81... Integrated circuit 811... Y-axis counter (position detection unit)
812: Imaging timing output unit (imaging timing control unit)
814: Interrupt generation unit (correction timing control unit)
92...Position measuring device (yawing measuring device)
Ma: alignment mark Re: irradiation range Ty: yawing correction table (first and second yawing correction information)
We...substrate Y...Y direction (main scanning direction)
Ya...Alignment movement range (second movement range)
Ye...Exposure movement range (first movement range)
θ…Rotation direction (yaw direction)
S102: Step (second main scanning drive)
S103: Step (alignment mark acquisition operation)
S104: Step (first main scanning drive)
S105: Step (exposure operation)
S201 to S206: Steps (first and second correction information creation operations)
S204: Step (first and second yawing measurement)

Claims (11)

a step of performing a first main scanning drive in which one of the driving objects, that is, a stage on which a substrate is placed and an exposure head which irradiates an irradiation area with light, is driven in a main scanning direction by a driving mechanism, so that the driving object moves through a first movement range in the main scanning direction and the substrate passes through the irradiation range relatively in the main scanning direction;
a step of executing a first yawing correction operation for correcting a rotation amount of the driven object in the yaw direction by the drive mechanism during execution of the first main scanning drive, based on first yawing correction information stored in a storage unit that stores first yawing correction information indicating a first correction amount for correcting a rotation amount of the driven object in the yaw direction according to a position of the driven object in the main scanning direction in the first movement range;
performing an exposure operation of exposing an area extending in the main scanning direction on the substrate by irradiating light from the exposure head onto the irradiation range during execution of the first main scanning drive ;
an output of an encoder provided in a servo motor of the driving mechanism that drives the driven object in the main scanning direction is counted by a counter;
An exposure method in which the first yawing correction information indicates a correspondence relationship between a position of the object to be driven in a main scanning direction indicated by the counter and a correction amount of the position of the object to be driven in the yaw direction . a step of executing a first correction information creating operation of creating the first yawing correction information based on a result of determining a rotation amount in the yaw direction of the driven object that is moved in the first movement range in the main scanning direction by the driving mechanism,
The exposure method according to claim 1 , wherein in the first yawing correction operation, a rotation amount in the yaw direction of the driven object is corrected based on the first yawing correction information created in the first correction information creation operation. a step of attaching a yawing measuring device to an exposure apparatus including the stage, the exposure head, and the driving mechanism, the yawing measuring device measuring an amount of rotation of the stage in the yaw direction by a laser interferometer;
a step of performing a first yawing measurement in which a rotation amount in the yaw direction of the driven object that moves in the first movement range is measured by the yawing measuring device by driving the driven object in the main scanning direction by the driving mechanism, and a position of the driven object in the main scanning direction and a rotation amount in the yaw direction are obtained in correspondence with each other;
3. The exposure method according to claim 2, wherein the first correction information creating operation includes a step of creating the first yawing correction information based on a result of the first yawing measurement. a step of performing a second main scanning drive in which the driven object is driven in the main scanning direction by the drive mechanism, so that the driven object moves through a second movement range in the main scanning direction and the substrate passes relatively through an imaging range of a camera in the main scanning direction;
executing a second yawing correction operation for correcting a rotation amount of the driven object in the yaw direction by the drive mechanism during execution of the second main scanning drive, based on second yawing correction information indicating a second correction amount for correcting a rotation amount of the driven object in the yaw direction in accordance with a position of the driven object in the second movement range in the main scanning direction;
a step of performing an alignment mark acquisition operation, before the execution of the exposure operation, of capturing an alignment mark image by capturing an image of an alignment mark of the substrate passing through the imaging range during the execution of the second main scanning drive with the camera, and acquiring a position of the alignment mark indicated by the alignment mark image;
4. The exposure method according to claim 1, wherein in the exposure operation, a pattern of light irradiated from the exposure head to the substrate is adjusted according to the position of the alignment mark acquired in the alignment mark acquisition operation. a step of executing a second correction information generating operation for generating the second yawing correction information based on a result of calculating a rotation amount in the yaw direction of the driven object that is moved in the second movement range in the main scanning direction by the driving mechanism,
The exposure method according to claim 4 , wherein in the second yawing correction operation, a rotation amount in the yaw direction of the driven object is corrected based on the second yawing correction information created in the second correction information creation operation. a step of attaching a yawing measuring device to an exposure apparatus including the stage, the exposure head, and the driving mechanism, the yawing measuring device measuring an amount of rotation of the stage in the yaw direction by a laser interferometer;
a step of performing a second yawing measurement in which a rotation amount in the yaw direction of the driven object that moves in the second movement range is measured by the yawing measuring device by driving the driven object in the main scanning direction by the driving mechanism, and a position of the driven object in the main scanning direction and a rotation amount in the yaw direction are obtained in correspondence with each other;
6. The exposure method according to claim 5, wherein the second correction information creating operation includes a step of creating the second yawing correction information based on a result of the second yawing measurement. In the alignment mark acquisition operation, a position of the driven object in the main scanning direction is detected by a position detection unit, and transmitted to an imaging timing control unit that controls timing of imaging by the camera, and the imaging timing control unit causes the camera to capture an image at a timing according to the position of the driven object in the main scanning direction received from the position detection unit, thereby capturing an image of the alignment mark;
7. The exposure method according to claim 4, wherein the position detection section and the imaging timing control section are provided in a single integrated circuit. a step of detecting a position of the driven object in the main scanning direction by a position detection unit, and transmitting the position to a correction timing control unit that controls a timing of execution of the first yawing correction operation by the driving mechanism,
the correction timing control unit causes the drive mechanism to execute the first yawing correction operation at a timing according to the position of the driven object in the main scanning direction received from the position detection unit;
8. The exposure method according to claim 1, wherein the position detection section and the correction timing control section are provided in a single integrated circuit. 9. The exposure method according to claim 1, wherein a plurality of different exposure positions in a sub-scanning direction are set on the substrate, and the first main scanning drive, the first yawing correction operation, and the exposure operation are repeated while changing a position of the driven object by the drive mechanism between a plurality of different sub-scanning positions in the sub-scanning direction that respectively correspond to the plurality of exposure positions,
the first yawing correction information is provided for each of the plurality of sub-scanning positions,
In the first yawing correction operation, a position of the object to be driven in the sub-scanning direction is corrected based on the first yawing correction information provided for the sub-scanning position where the object to be driven is located. 9. The exposure method according to claim 1, wherein a plurality of different exposure positions in a sub-scanning direction are set on the substrate, and the first main scanning drive, the first yawing correction operation, and the exposure operation are repeated while changing a position of the driven object by the drive mechanism between a plurality of different sub-scanning positions in the sub-scanning direction that respectively correspond to the plurality of exposure positions,
the first yawing correction information is provided for each of a plurality of different setting positions in the sub-scanning direction,
the plurality of set positions is less than the plurality of sub-scanning positions,
In the first yawing correction operation, an exposure method is provided in which the position of the driven object in the sub-scanning direction is corrected based on the first yawing correction information provided for the setting position among the multiple setting positions that is closest to the sub-scanning position where the driven object is located, or by linear interpolation using the first yawing correction information provided for the setting position closest to the sub-scanning position and the first yawing correction information provided for the setting position second closest to the sub-scanning position. a stage on which a substrate is placed;
an exposure head that irradiates light onto an irradiation area;
a driving mechanism that drives one of the stage and the exposure head in a main scanning direction;
a storage unit configured to store first yawing correction information indicating a first correction amount for correcting a rotation amount in a yaw direction of the driven object in accordance with a position of the driven object in the main scanning direction within a first movement range in the main scanning direction;
a control unit that performs an exposure operation to expose an area of the substrate extending in the main scanning direction by irradiating light from the exposure head onto the irradiation range while performing a first main scanning drive in which the drive mechanism drives the drive target in the main scanning direction, causing the drive target to move through the first movement range and the substrate to relatively pass through the irradiation range in the main scanning direction ; and
a counter that counts the output of an encoder provided in a servo motor of the driving mechanism that drives the driven object in the main scanning direction;
Equipped with
the first yawing correction information indicates a correspondence relationship between a position of the driven object in a main scanning direction indicated by the counter and a correction amount of the position of the driven object in a yaw direction,
The control unit performs a first yawing correction operation to correct the amount of rotation of the driven object in the yaw direction while the first main scanning drive is being performed, based on the first yawing correction information, using the drive mechanism.

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