JPH11251231A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aligner, wherein accurate alignment is performed even if coarse alignment is omitted for a replaced substrate, with improved throughput, regarding an aligner used in a photolithography process for manufacturing a semiconductor device, a liquid crystal display device, of a thin-film magnetic head, etc. SOLUTION: A mask 108 comprising a pattern and a plate 104 are moved synchronously in a specified movement direction, and the pattern is exposed in the plate 104. Here, for at least one of the mask 108 and the plate 104, a plurality of mirrors 114, 115, 118, and 119 so allocated as to partially overlap in movement direction, and interferometers 131 and 132 which detect information regarding at least one position of the mask 108 and the plate 104 in cooperation with the mirrors, are constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus used in a photolithography process for manufacturing a semiconductor device, a liquid crystal display, a thin film magnetic head, and the like.

[0002]

2. Description of the Related Art Conventionally, in a photolithography process for manufacturing a semiconductor device, a liquid crystal display device, a thin film magnetic head, or the like, a wafer on which a photoresist or a pattern image of a mask or a reticle (hereinafter, referred to as a mask) is applied. Alternatively, an exposure apparatus that exposes a substrate such as a glass plate (hereinafter, referred to as a plate) is used. As an example of such an exposure apparatus, a scanning projection exposure apparatus that integrally holds a plate and a mask, scans the projection optical system, and transfers a pattern to the plate will be described with reference to FIG. 2, it is assumed that the X axis is taken in the scanning direction of the carriage 101, the Y axis is taken perpendicular to the installation surface, and the Z axis is taken perpendicular to the X axis and the Y axis. The exposure apparatus includes a carriage 1 having a U-shaped cross section.
01. The carriage 101 is slidably supported in the X direction on a surface plate 116 by a guide (not shown) provided in the X direction.

FIG. 3 shows a wall portion 121 on the −Z direction side of the carriage 101. The coordinate system in FIG.
Are the same as those shown in FIG. The mask stage 103 is provided on the wall 121. Mask stage 1
Numeral 03 supports the mask 108 shown by a broken line in the figure, and drives the mask stage driving mechanisms 201, 202, and 203 to allow fine movement in the X, Y, and Z axes. FIG. 4 shows a wall portion 120 on the + Z direction side of the carriage 101. The coordinate system in FIG. 4 is the same as that shown in FIG. This wall 12
At 0, a plate stage 102 is provided. The plate stage 102 is a plate 1 indicated by a broken line in the figure.
04 can be suction-held by a suction mechanism (not shown). The plate stage 102 is
Two reference pins 30 arranged in the X direction on the Y direction side bottom surface
1, 302. The bottom of the plate 104 sucked to the plate stage 102 has the reference pin 30.
By being brought into contact with the first and second substrates 302, they are positioned on the plate stage 102 in the Y direction. Further, the plate stage 102 has a pre-alignment measuring mechanism 303 on a side surface portion extending in the Y direction on the −X direction side. X from
An axial displacement can be detected.

[0004] Returning to FIG.
Alignment microscopes 106 and 107 are provided on the direction side. The alignment microscopes 106 and 107 can observe the plate 104 via a mask 108 and a projection optical system (not shown). Based on the observation results by the alignment microscopes 106 and 107,
The control device (not shown) includes the plate 104 and the mask 10.
8 is performed.

[0005] An illumination optical system (not shown) is provided on the −Z direction side of the mask stage 103, and the mask 1 held by the mask stage 103 is provided by the illumination optical system.
A part of the pattern area 08 is uniformly illuminated. Both walls 120 and 12 of the carriage 101
A projection optical system (not shown) that forms an equal-size erect real image on an image forming plane is provided in the space between the two.

A plate transport mechanism 105 is provided for exchanging the plate 104 after the exposure with the plate 104 to be exposed next. The position where the loading and unloading of the plate 104 for plate exchange is performed is as follows.
The plate replacement position C is indicated by a broken line on the + X direction side of the scanning movement range of the carriage 101. At the plate exchange position C, the plate 104 can be carried in and out of the plate stage 102 by the plate transport mechanism 105.

[0007] Further, the wall portion 120 of the carriage 101
On the side surface on the X direction side, there are provided reflecting mirrors 122, 123, and 124 formed of, for example, corner cube prisms. On the other hand, near the mask stage 103 on the side surface of the wall portion 121 of the carriage 101 on the −X direction side, reflecting mirrors 125 and 126 formed of corner cube prisms are provided. The reflecting mirrors 125 and 126 are used for the mask stage 1
The fine movement follows the fine movement of 03. The reflecting mirror 122 and the reflecting mirror 125 are arranged at substantially the same Y-direction position, and the reflecting mirror 124 and the reflecting mirror 126 are also arranged at substantially the same Y-direction position. Reflecting mirrors 122, 125
In FIG. 1, beams 110 from a first interferometer (not shown) branched by a beam splitter or a reflecting mirror (not shown) are incident parallel to the X axis. The beam 110 reflected by the reflecting mirrors 122 and 125 travels in the reverse direction of the original optical path, enters the first interferometer and interferes with it. The interference fringes are counted, and the positions of the reflecting mirror 122 and the reflecting mirror 125 in the X direction are counted. Is detected.

The beams 111 from a beam splitter (not shown) or a second interferometer (not shown) branched by a reflecting mirror are incident on the reflecting mirrors 124 and 126 in parallel with the X axis. Has become. Reflector 124, 12
The beam 111 reflected at 6 travels in the reverse direction of the original optical path, enters the second interferometer and interferes with it. The interference fringes are counted, and the relative displacement of the positions of the reflecting mirror 124 and the reflecting mirror 126 in the X direction is changed. Is to be detected. Also, the reflecting mirror 1
23 includes a beam 109 from a third interferometer (not shown).
Are incident parallel to the X-axis. Reflector 1
The beam 109 reflected by 23 enters the third interferometer and interferes with a reference beam (not shown), the interference fringes are counted, and the amount of movement of the reflecting mirror 123 from a predetermined position in the X direction is detected. You.

A reflecting mirror 127 having a reflecting surface for reflecting a beam incident parallel to the X axis in the + Y direction is provided substantially at the center of the side surface on the + Y direction side of the wall portion 120. On the other hand, a reflection mirror 129 having a reflection surface for reflecting a beam incident parallel to the X axis in the + Y direction is provided substantially at the center of the side surface on the + Y direction side of the mask stage 103. The reflecting mirror 129 is finely moved following fine movement of the mask stage 103 in the Y direction. On the + Y direction side of the reflecting mirror 127, there is provided a plane mirror (mirror) 114 for making the beam bent in the + Y direction from the reflecting mirror 127 incident almost perpendicularly. The mirror 114 is
The longitudinal mirror is a long mirror provided along the moving direction (X direction) of the carriage 101 during scanning exposure, and has a length substantially equal to the scanning moving range of the carriage 101 in the longitudinal direction, and has a predetermined flatness. Has been maintained and fixed. On the other hand, on the + Y direction side of the reflecting mirror 129, there is also provided a plane mirror (mirror) 115 for making the beam bent in the + Y direction from the reflecting mirror 129 incident almost perpendicularly. Mirror 1
Reference numeral 15 also denotes a long mirror whose longitudinal direction is provided along the moving direction (X direction) of the carriage 101 at the time of scanning exposure, similar to the mirror 114, and whose longitudinal direction is substantially equal to the scanning movement range of the carriage 101. It is fixed while maintaining a predetermined flatness.

A beam 113 from a fourth interferometer (not shown) branched by a beam splitter (not shown) or a reflecting mirror (not shown) is incident on the reflecting mirrors 127 and 129 so as to be incident parallel to the X axis. Has become. Reflector 127, 12
9 is reflected by mirrors 114, 1
The light is vertically reflected at 15 and travels in the reverse direction of the original optical path, enters the fourth interferometer and interferes. The interference fringes are counted, and the relative displacement of the positions of the reflecting mirrors 127 and 129 in the Y direction is calculated. It can be detected.

The displacement information detected by the first, second, third, and fourth interferometers is input to a controller (not shown). The control device detects a relative position between the mask 108 and the plate 104 based on the displacement information input from the first to fourth interferometers, and based on the relative position, the mask 108 and the plate 104 move to a predetermined position. The mask stage driving mechanisms 201, 202, and 203 can be controlled to drive the mask stage 103 so that the relationship is maintained.

An operation of an exposure process (so-called second exposure) for transferring a pattern of the second and subsequent layers onto the plate 104 in such a conventional exposure apparatus will be described. Mask 10 for transferring patterns of the second and subsequent layers
8 is already held on the mask stage 103. First, the carriage 101 is moved to the plate exchange position C by a carriage driving mechanism (not shown). At the plate exchange position C, the plate transport mechanism 105 carries the plate 104 to be processed into the plate stage 102. Next, the following alignment is performed in order to accurately overlap a pattern already formed on the plate 104 with a pattern to be formed on the plate 104 next. FIG. 5 shows the plate 104 and the mask 108.
The marks used for the above alignment and the flow of alignment using these marks are shown.

The plate 104 has an alignment mark 401 as shown in FIG. The alignment mark 401 is formed at the time of the first exposure processing on the plate 104 (so-called first exposure). As shown in FIG. 5, the mask 108 includes a coarse alignment coarse alignment mark 402 formed of a rectangular light transmitting region, a protection pattern 404 having a light shielding pattern formed on the entire surface, and an alignment mark 40 of the plate 104.
1 and a fine alignment mark 403 for performing accurate alignment are formed with a predetermined positional relationship in the Y direction.

First, the pre-alignment measuring system 303 shown in FIG. 4 measures the displacement of the plate 104 held on the plate stage 102 from the reference position in the X direction.
Based on the measurement result, the control device specifies the position of the alignment mark 401 on the plate 104, and controls the carriage driving mechanism so that the alignment mark 401 enters the observation field of the alignment microscope 106 (or the alignment microscope 107). The carriage 101 is moved. Next, the mask stage driving mechanisms 201, 202,
By controlling the mask stage 103, the mask stage 103 is driven, and as shown in FIG.
The coarse adjustment is performed so as to fall within the range (hereinafter, this coarse adjustment operation is referred to as course alignment).

Next, while the coarse alignment mark 402 is being observed by the alignment microscope 106, the mask stage driving mechanisms 202 and 203 are controlled so that only the difference between the position of the coarse alignment mark 402 and the position of the fine alignment mark 403 is obtained. The mask stage 103 is moved, and as shown in FIG.
Fine alignment mark 40 in the observation field of view 06
3 and fine adjustment is performed by measuring the relative displacement between the fine alignment mark 403 and the alignment mark 401 (this fine adjustment operation is hereinafter referred to as fine alignment). Note that when the exposure operation is started, the alignment mark 401 formed on the plate 104 is not destroyed by the irradiation of the exposure light, as shown in FIG.
As shown in (2), the mask stage 103 is moved by the difference between the positions of the fine alignment mark 403 and the protection pattern 404 so that the protection pattern 404 blocks exposure of the alignment mark 401 to exposure light.

When the above alignment is completed,
The illumination light emitted from the illumination optical system uniformly illuminates a part of the pattern area of the mask 108. The transmitted light of the illumination light illuminating a part of the pattern area of the mask 108 is incident on the projection optical system, and is placed on the plate 104 held by the plate stage 102 so that an equal-size erect real image of a part of the pattern area of the mask 108 is formed. Is projected. Along with such an operation, the carriage 101 moves in the X-axis direction along the guide, and scans the mask 108 and the plate 104 in synchronization with the projection optical system. The image is transferred onto the image 104 at the same magnification. Also,
While the carriage 101 is performing the scanning movement, the control device controls the mask stage driving mechanisms 201, 202, and 203 based on the displacement information from the first to fourth interferometers to drive the mask stage 103, The mask 108 and the plate 104 are maintained in a predetermined positional relationship.

When the exposure operation for a predetermined plate 104 is completed, the carriage 101 moves to the plate exchange position C, and the plate transport mechanism 105 carries out the exposed plate 104 and places the next plate 104 on the plate stage 102. Bring in. Next, the above-described alignment is performed again on the loaded plate 104, and then the operation shifts to the exposure operation.

[0018]

In the conventional exposure apparatus described above, when the carriage 101 is at the plate exchange position C, the beam 113 from the fourth interferometer is reflected by the reflecting mirrors 127 and 129. Inject in + Y direction,
Since the mirrors 114 and 115 do not exist at the plate exchange position C, the beam 113 cannot return to the fourth interferometer,
The counter that counts the interference fringes in the fourth interferometer is reset to zero. That is, in the conventional exposure apparatus,
With the operation of exchanging the plate 104, the mask stage 10
Information on the relative position of the plate stage 102 with respect to the Y-axis direction is lost. Therefore, after the replacement, the position of the plate 104 supported by the plate stage 102 and the mask 108 must be re-aligned from the course alignment, and the throughput cannot be improved.

On the other hand, it is conceivable that the length of the mirrors 114 and 115 in the longitudinal direction is made longer than the moving distance in the X direction in the exposure operation of the carriage 101 to extend the plate to the plate exchange position C. In this way, the beam 113 can be returned to the fourth interferometer. However, it is not practical to extend the mirrors 114 and 115 formed with a predetermined flatness in the longitudinal direction because of the great difficulty in manufacturing the mirrors. First, it is difficult to provide a predetermined flatness to the entire length of the long mirror. Second, when the long mirror is installed in an exposure apparatus, the deflection of the long mirror due to its own weight is suppressed. Third, it is difficult to reduce the manufacturing cost of a long long mirror and the manufacturing cost of a complicated installation mechanism for installing the long mirror. SUMMARY OF THE INVENTION It is an object of the present invention to provide an exposure apparatus capable of performing accurate alignment even when course alignment is omitted for a replaced substrate. It is another object of the present invention to provide an exposure apparatus in which throughput is improved by omitting course alignment.

[0020]

The object of the present invention will be described with reference to FIG. 1 showing an embodiment of the present invention. The object is to move a mask (108) having a pattern and a substrate (104) in a predetermined moving direction. Move the pattern synchronously to the substrate (104)
A plurality of mirrors (114 and 118, 115 and 119) disposed so as to partially overlap in the moving direction in relation to at least one of the mask (108) and the substrate (104). And interferometers (131, 1) for detecting information about the position of at least one of the mask (108) and the substrate (104) in cooperation with a plurality of mirrors (114 and 118, 115 and 119).
32), which is achieved by an exposure apparatus. In the exposure apparatus of the present invention, the plurality of mirrors are a pair of mirrors (114 and 1) arranged in relation to the mask (108) and the substrate (104), respectively.
18 and 115 and 119) and the interferometer (131,
132) detects the relative displacement between the mask (108) and the substrate (104). In the exposure apparatus of the present invention, a plurality of mirrors (114, 118, 11
5 and 119) are characterized in that the mirrors have different degrees of flatness accuracy. In the exposure apparatus of the present invention, a correction device (133, 201, 202, 203) for correcting the position of the mask (108) and the substrate (104) according to the detection result of the interferometer (131, 132) is provided. It is characterized by having. Further, the exposure apparatus of the present invention includes a mask stage (103) for supporting the mask (108) in the vertical direction and a substrate stage (102) for supporting the substrate (104) in the vertical direction. It is characterized by.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An exposure apparatus according to an embodiment of the present invention will be described with reference to FIG. First, a schematic configuration of an exposure apparatus according to the present embodiment will be described with reference to FIG. In this embodiment, a scanning projection exposure apparatus that transfers a pattern by scanning a projection optical system while holding a mask and a plate integrally in a vertical direction will be described as an example. Here, it is assumed that the X axis is taken in the scanning direction of the carriage 101, the Y axis is taken perpendicular to the installation surface, and the Z axis is taken perpendicular to the X axis and the Y axis. Note that components having the same functions and functions as those of the conventional exposure apparatus shown in FIG. 2 are denoted by the same reference numerals. The exposure apparatus has a carriage 101 having a U-shaped cross section. The carriage 101 is slidably supported in the X direction on a surface plate 116 by a guide (not shown) provided in the X direction. In the present exposure apparatus, the wall portion 120 on the + Z direction side and the wall portion 121 on the −Z direction side of the carriage 101 are:
This is the same as the conventional exposure apparatus described with reference to FIGS.

Referring to FIG.
Alignment microscopes 106 and 107 are provided on the Z direction side. The alignment microscopes 106 and 107
The rectangular plate 104 can be observed through the mask 108 and a projection optical system (not shown). Based on the observation information from the alignment microscopes 106 and 107, the control device 133 performs alignment between the plate 104 and the mask 108 on which a circuit pattern (for example, a liquid crystal display element pattern) is formed.

An illumination optical system (not shown) is provided on the −Z direction side of the mask stage 103. The mask 1 held by the mask stage 103 is provided by the illumination optical system.
A part of the pattern area 08 is uniformly illuminated. Both walls 120 and 12 of the carriage 101
A projection optical system (not shown) that forms an equal-size erect real image on an image forming plane is provided in the space between the two. Further, at a plate exchange position C on the + X direction side of the scanning movement range of the carriage 101, the plate 104 can be carried in and out of the plate stage 102 by the plate transport mechanism 105.

Further, the wall portion 120 of the carriage 101
On the side surface on the X direction side, there are provided reflecting mirrors 122, 123, and 124 formed of, for example, corner cube prisms. On the other hand, near the mask stage 103 on the side surface of the wall portion 121 of the carriage 101 on the −X direction side, reflecting mirrors 125 and 126 formed of corner cube prisms are provided. The reflecting mirrors 125 and 126 are used for the mask stage 1
The fine movement follows the fine movement of 03. The reflecting mirrors 122 and 125 are arranged at substantially the same Y-direction position,
The reflecting mirrors 124 and 126 are arranged at substantially the same Y-direction position. The beams 110 from a first interferometer (not shown) branched by a not-shown beam splitter or a reflecting mirror are respectively incident on the reflecting mirrors 122 and 125 in parallel to the X axis. Reflecting mirrors 122, 125
The beam 110 reflected by the first optical path travels in the reverse direction of the original optical path and
The light enters and interferes with the interferometer, and the interference fringes are counted, and the relative displacement of the positions of the reflecting mirror 122 and the reflecting mirror 125 in the X direction is detected.

The beams 111 from a beam splitter (not shown) or a second interferometer (not shown) branched by a reflecting mirror are respectively incident on the reflecting mirrors 124 and 126 so as to be incident parallel to the X axis. Has become. Reflector 124, 12
The beam 111 reflected at 6 travels in the reverse direction of the original optical path, enters the second interferometer and interferes with it. The interference fringes are counted, and the relative displacement of the positions of the reflecting mirror 124 and the reflecting mirror 126 in the X direction is changed. Is to be detected. Also, the reflecting mirror 1
23 includes a beam 109 from a third interferometer (not shown).
Are incident parallel to the X-axis. Reflector 1
The beam 109 reflected by 23 enters the third interferometer and interferes with a reference beam (not shown), the interference fringes are counted, and the amount of movement of the reflecting mirror 123 from a predetermined position in the X direction is detected. You.

In the center of the side surface on the + Y direction side of the wall portion 120, two beams 11 incident parallel to the X axis are provided.
Two reflecting mirrors 127 and 128 having reflecting surfaces for reflecting 3, 117 in the + Y direction are provided side by side in the Z direction. On the other hand, a reflection surface for reflecting a beam obtained by splitting the two beams 113 and 117 in the + Y direction is provided substantially at the center of the side surface on the + Y direction side of the mask stage 103.
Two reflecting mirrors 129 and 130 are provided side by side in the Z direction. The reflecting mirrors 129 and 130 are finely moved following fine movement of the mask stage 103 in the Y direction.

On the + Y direction side of the reflecting mirror 127, a mirror 114 for making the beam bent in the + Y direction from the reflecting mirror 127 incident almost vertically is provided on the scanning movement range of the carriage 101. The mirror 114 is a long mirror whose longitudinal direction is provided above the plate 104 along the moving direction (X direction) of the carriage 101 during scanning exposure, and the longitudinal direction is substantially equal to the scanning movement range of the carriage 101. Has a length. Also, the mirror 114
Is fixed while maintaining a predetermined flatness within a measurement range in the X direction. On the other hand, on the + Y direction side of the reflecting mirror 129,
A mirror 115 for causing the beam bent in the + Y direction from the reflecting mirror 129 to enter almost vertically is provided on the scanning movement range of the carriage 101. The mirror 115 is also a long mirror whose longitudinal direction is provided above the mask 108 along the moving direction (X direction) of the carriage 101 during scanning exposure, and the longitudinal direction is substantially equal to the scanning movement range of the carriage 101. Has a length. Also, the mirror 115
Is fixed while maintaining a predetermined flatness within a measurement range in the X direction.

Further, on the + Y direction side of the reflecting mirror 128 provided in parallel with the reflecting mirror 127,
A plane mirror (mirror) 118 for making the beam bent in the direction substantially perpendicular to the mirror is provided in parallel with the mirror 114 in the X direction in the same XZ plane. Mirror 1
Reference numeral 18 denotes a long mirror whose longitudinal direction is provided along the moving direction (X direction) of the carriage 101 at the time of scanning exposure.
And extends to a region where position measurement in the Y direction at the plate exchange position C can be performed. Also, the mirror 118
Is fixed while maintaining the same flatness as the mirror 114. On the other hand, on the + Y direction side of the reflecting mirror 130 provided in parallel with the reflecting mirror 129, a plane mirror (mirror) 119 that makes the beam bent in the + Y direction from the reflecting mirror 130 enter almost vertically is the same X-Z. X in plane
It is juxtaposed with the mirror 115 in the direction. The mirror 119 moves the carriage 10 in the longitudinal direction during scanning exposure.
1 is a long mirror provided along the movement direction (X direction), and its longitudinal direction extends to the + X direction side from the scanning movement range of the carriage 101, and can measure the position in the Y direction at the plate exchange position C. Extending to the area. Mirror 1
Reference numeral 19 is fixed while maintaining a predetermined flatness substantially similar to that of the mirror 115.

The beams 113 from the fourth interferometer 131 branched by a beam splitter (not shown) or a reflecting mirror (not shown) are incident on the reflecting mirrors 127 and 129 in parallel with the X axis. Within the scanning movement range of the carriage 101, the beam 113 reflected by the reflecting mirrors 127 and 129 is further reflected vertically by the mirrors 114 and 115, travels in the reverse optical path, and enters the fourth interferometer 131. Interfere with each other, and the interference fringes are counted and reflected by the reflection mirror 127.
And the relative displacement of the position of the reflecting mirror 129 in the Y direction is detected. That is, the fourth interferometer 131
Detects the relative shift amount in the Y direction between the plate 104 and the mask 108 within the scanning movement range.

Further, beams 117 from a fifth interferometer 132 branched by a beam splitter (not shown) or a reflecting mirror (not shown) are incident on the reflecting mirrors 128 and 130 in parallel with the X axis. Within the range from the area where the mirrors 118 and 119 partially overlap the mirrors 114 and 115 to the plate exchange position C,
The beam 117 reflected from the mirrors 8 and 130 is further reflected on the mirror 1
The light is reflected vertically at 18, 119, and travels in the reverse direction of the original optical path.
The light enters the fifth interferometer 132 and interferes with it. The interference fringes are counted, and the relative displacement of the positions of the reflecting mirror 128 and the reflecting mirror 130 in the Y direction is detected. That is, the fifth interferometer 132 controls the plate 1 outside the scanning movement range.
The relative displacement between the mask 04 and the mask 108 in the Y direction is detected.

The count values of the interference fringes counted by each of the first interferometer, the second interferometer, the third interferometer, the fourth interferometer 131 and the fifth interferometer 132 are determined by the control unit at a predetermined sampling interval. 133. Further, the control device 133 sets each counter value of the first interferometer and the second interferometer at the time when the alignment of the mask 108 and the plate 104 is completed as an X-direction reference value, and uses the count value of the fourth interferometer 131 as the reference value. It is stored as a Y-direction reference value. The control device 133 compares the count value of each displacement amount from the first, second, and fourth interferometers 131 with the respective reference values during the scanning movement of the carriage 101, and determines the relative position between the mask 108 and the plate 104. The mask stage driving mechanism 20 detects a change in the position and allows the mask 108 and the plate 104 to always maintain a predetermined alignment state during the scanning movement of the carriage 101.
1, 202 and 203 are controlled to drive the mask stage 103.

Further, the control device 133 controls the carriage 10
When the first interferometer 1 moves to the plate exchange position C, the area where the position measurement in the Y direction can be performed by both the fourth interferometer 131 and the fifth interferometer 132, ie, the mirror 114 and the mirror
18 and the mirror 115 and the mirror 11
After the counter value of the fifth interferometer 132 is reset in a partially overlapping area with the counter value 9, the difference value obtained by subtracting the counter value of the fourth interferometer 131 from the counter value of the fifth interferometer 132 is used as the Y-direction reference value. In addition, it is stored as a new Y-direction reference value.

After exchanging the plate 104 at the plate exchanging position C, the control device 133 uses the pre-alignment measuring mechanism 303 to determine the amount of displacement of the exchanged plate 104 in the X direction from the reference position on the plate stage 102. The measured and previously stored X-direction reference value of the plate 104 before replacement is added with the positional deviation amount converted to the counter value and stored as a new X-direction reference value. At the same time, the control device 133 compares the new X-direction reference value with the count values of the first interferometer and the second interferometer to detect a change in the relative position between the mask 108 and the plate 104 in the X direction. The stage drive mechanism 201 is controlled to drive the mask stage 103 in the X direction by a predetermined amount.

Further, the control device 133 controls the carriage 10
1 is from plate exchange position C in preparation for scanning exposure-
In the case of moving in the X direction, both the fourth interferometer 131 and the fifth interferometer 132 can perform position measurement in the Y direction, that is, the partially overlapping area of the mirror 114 and the mirror 118 and the mirror 118 After the counter value of the fourth interferometer 131 is reset in a partially overlapping area between the first interferometer 131 and the mirror 119, a difference value obtained by subtracting the counter value of the fifth interferometer 132 from the counter value of the fourth interferometer 131 is used as a Y-direction reference. It is stored as a new Y-direction reference value in addition to the value. Thereafter, the control device 133 compares the count value of each displacement amount from the first, second, and fourth interferometers 131 with each reference value during the scanning movement of the carriage 101, and compares the mask 108 with the plate 104. The relative position change with respect to
The mask stage driving mechanisms 201, 202 and 203 are controlled to drive the mask stage 103 so that the plate and the plate 104 can always maintain a predetermined alignment state during the scanning movement of the carriage 101.

Next, the exposure operation of the exposure apparatus according to the present embodiment will be described. First, the operation of the present exposure apparatus when performing the second exposure on the first plate 104 of a lot (processing unit) will be described. Here, the mask 104 on which the pattern to be transferred by the second exposure is formed
Are already held on the mask stage 103. The carriage 101 is moved to the plate exchange position C by a carriage driving mechanism (not shown). At this position C, the plate transport mechanism 105
04 is carried into the plate stage 102. Next, coarse alignment and fine alignment are performed to accurately overlap the pattern already formed on the plate 104 with the pattern to be formed on the plate 104 next. This operation is the same as the alignment operation in the conventional exposure apparatus described with reference to FIG.

After the alignment is completed, the illumination light emitted from the illumination optical system uniformly illuminates a part of the pattern area of the mask 108. The transmitted light of the illumination light illuminating a part of the pattern area of the mask 108 enters the projection optical system,
On the plate 104 held on the plate stage 102, a 1: 1 erect real image of a part of the pattern region of the mask 108 is projected. With such an operation, the carriage 101
Moves along the guide in the X-axis direction, and scans the mask 108 and the plate 104 in synchronization with the projection optical system, whereby the entire pattern on the mask 108 is transferred onto the plate 104 at the same magnification. You. Further, while the carriage 101 is performing the scanning movement, the control device 133
The relative position change between the mask 108 and the plate 104 is detected by comparing the count value of each displacement amount from the first, second and fourth interferometers 131 with each reference value, and
The mask stage driving mechanism 201, 202, 203 is controlled to drive the mask stage 103 so that the mask stage 8 and the plate 104 can always maintain a predetermined alignment state during the scanning movement of the carriage 101.

Next, the operation when the second exposure is performed on the next plate 104 will be described. When the exposure operation for the first plate 104 is completed as described above, the carriage 101 is moved to the plate exchange position C by the carriage driving mechanism. Along with such an operation, the controller 133 controls the fourth interferometer 131 and the fifth interferometer 13
2 are mirrors 114, 1 which can simultaneously detect displacement in the Y direction.
In a partially overlapping area of the mirror 15 and the mirrors 118 and 119, the counter value of the fifth interferometer 132 is reset, and then the difference value obtained by subtracting the counter value of the fourth interferometer 131 from the counter value of the fifth interferometer 132 Is stored as a new Y-direction reference value in addition to the Y-direction reference value.

Next, at the plate exchange position C, the plate
04 is unloaded and the next plate 104 to be exposed
Is carried into the plate stage 102. Plate 10
4 are reference pins 301 and 302 of the plate stage 102
Supported by the plate stage 102,
The pre-alignment measurement mechanism 303 measures the amount of displacement in the X direction from the reference position on the plate stage 102 with respect to the plate 104 after replacement. Control device 1
Reference numeral 33 denotes a value added to the X-direction reference value of the plate 104 before replacement, which is already stored, which is converted into a counter value and stored as a new X-direction reference value. By comparing the count values of the first interferometer and the second interferometer with each other to detect a change in the relative position of the mask 108 and the plate 104 in the X direction, the mask stage driving mechanism 201 is controlled to move the mask stage 103 in the X direction. Is driven by a predetermined amount.

By doing so, the X-direction alignment information between the plate 104 and the mask 108 before replacement can be reflected on the X-direction alignment between the plate 104 and the mask 108 after replacement. . The position of the plate 104 in the Y direction before and after replacement is determined by the reference pin 30 fixed to the plate stage 102.
1, 302, the displacement of the plate 104 on the plate stage 102 in the Y direction does not occur due to the plate exchange.

Next, the carriage 101 is moved from the plate exchange position C to the -X direction in preparation for scanning exposure by the carriage driving mechanism. Along with this operation, a region where the position measurement in the Y direction can be performed by both the fourth interferometer 131 and the fifth interferometer 132, that is, the mirror 114 and the mirror 1
18 and the mirror 115 and the mirror 11
After the counter value of the fourth interferometer 131 is reset in the partially overlapping area with the counter value 9, the difference value obtained by subtracting the counter value of the fifth interferometer 132 from the counter value of the fourth interferometer 131 is used as the Y-direction reference value. In addition, it is stored as a new Y-direction reference value.

Thereafter, the control device 133 operates the carriage 1
During the scanning movement of No. 01, the relative position change between the mask 108 and the plate 104 is detected by comparing the count value of each displacement amount from the first, second and fourth interferometers 131 with each reference value, The mask stage driving mechanisms 201 and 20 allow the mask 108 and the plate 104 to always maintain a predetermined alignment state during the scanning movement of the carriage 101.
The mask stage 103 is driven by controlling 2 and 203.

By doing so, the positional relationship between the fine alignment mark 403 of the mask 108 and the alignment mark 401 of the plate 104 can be almost specified, so that the fine alignment can be performed immediately without performing the course alignment again. Will be able to run. When the fine alignment is completed, the same scanning exposure as that of the first plate 104 of the lot described above is performed. In the subsequent second exposure for the plate 104, fine alignment can be performed immediately without performing the course alignment and the operation can be shifted to the exposure operation in the same manner as described above.
Throughput can be improved.

The present invention is not limited to the above embodiment, but can be variously modified. For example, in the above embodiment, the exposure processing in which the plate and the mask are held in the vertical direction and the scanning exposure is performed is described. However, the present invention is not limited to this. It can also be applied to devices. In the above embodiment, the mirrors 114 and 115 and the mirror 118,
Although the reflection plane 119 is formed with substantially the same high precision, the present invention is not limited to this, and is used for detecting the relative shift amount in the Y direction between the plate 104 and the mask 108 outside the scanning movement range. The surface accuracy of the reflecting planes of the mirrors 118 and 119 may be lower than the surface accuracy of the reflecting planes of the mirrors 114 and 115. Thereby, the mirrors 118, 1
19 can be reduced. In the above-described embodiment, the alignment when the plate 104 is replaced has been described. However, the present invention is not limited to this, and can be similarly applied to the alignment when the mask 108 is replaced.

[0044]

As described above, according to the present invention, it is possible to appropriately detect information on the position of at least one of the mask and the substrate without using a long mirror. Furthermore, since it is not necessary to perform at least the course alignment after replacing the substrates, the alignment time can be reduced, and the throughput of the exposure processing can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a conventional exposure apparatus.

FIG. 3 is a diagram illustrating a schematic configuration of a wall portion on the −Z direction side of the exposure apparatus.

FIG. 4 is a diagram showing a schematic configuration of a wall portion on the + Z direction side of the exposure apparatus.

FIG. 5 is a diagram illustrating alignment by a conventional exposure apparatus.

[Explanation of symbols]

101 Carriage 102 Plate stage 103 Mask stage 104 Plate 105 Plate transport mechanism 106, 107 Alignment microscope 108 Mask 114, 115, 118, 119 Mirror 116 Surface plate 120, 121 Wall 122, 123, 124, 125, 126, 127, 1
28, 129, 130 Reflecting mirror 131 Fourth interferometer 132 Fifth interferometer 133 Control device 201, 202, 203 Mask stage drive mechanism 301 Prescan measurement mechanism 302, 303 Reference pin

Claims (5)

[Claims] An exposure apparatus for synchronously moving a mask having a pattern and a substrate in a predetermined moving direction and exposing the pattern to the substrate, wherein at least one of the mask and the substrate is exposed.
A plurality of mirrors arranged so as to partially overlap in the moving direction; and an interferometer for detecting information on at least one position of the mask and the substrate in cooperation with the plurality of mirrors. An exposure apparatus characterized in that: 2. The exposure apparatus according to claim 1, wherein the plurality of mirrors are a pair of mirrors arranged in association with each of the mask and the substrate, and the interferometer is configured to include the mask and the mask. An exposure apparatus for detecting a relative displacement with respect to a substrate. 3. The exposure apparatus according to claim 1, wherein the plurality of mirrors have different degrees of accuracy with respect to the flatness of the mirrors. 4. The exposure apparatus according to claim 1, further comprising: a correction device configured to correct a position between the mask and the substrate according to a detection result of the interferometer. Exposure equipment. 5. The exposure apparatus according to claim 1, further comprising: a mask stage that supports the mask in a vertical direction; and a substrate stage that supports the substrate in a vertical direction. An exposure apparatus comprising: