JPH1027738A - Scanning exposure method and manufacture of device thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a mask and a wafer to be easily aligned with each other by a method wherein a mask reference plate is disposed on a mask stage, the relative positions of marks on the surface of the mask reference plate and other marks on a wafer reference plate on a wafer stage are measured with a microscope. SOLUTION: Mask alignment marks 40(a) and 40(b) provided onto a mask reference plate 10 are observed with an observation microscope 7, and the positions of them are measured respectively. A mask stage 4 is drive, the positions of marks 42(a) and 42(b) provided onto a mask 1 are measured by the observation microscope 7. The amount of drive required for the mask stage 4 is obtained by a laser interferometer 80, the positional deviation of the mask 1 from the mask reference plate 10 is calculated through an operation circuit 102, and the scanning direction of the mask 1 is made coincident with the travel of the mask stage 6. Then, a mask 55 on a stage reference plate 12 is driven to the center of an exposure pattern and then furthermore moved under an off-axis microscope 31, the position of the mask 35 is measured, and the mask 1 and the wafer 3 are aligned with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure method used in a semiconductor manufacturing process, and more particularly to a projection exposure method for projecting and transferring a photomask pattern onto a wafer. This method is most suitable for a scanning exposure method in which a mask and a wafer are scanned in synchronization with a projection optical system when projection exposure is performed on a wafer.

[0002]

2. Description of the Related Art Recent advances in semiconductor device manufacturing technology have been remarkable, and the accompanying fine processing technology has also advanced remarkably.
In particular, in optical processing technology, a reduction projection exposure apparatus having a submicron resolution, a so-called stepper, is the mainstream. To further improve the resolution, it is necessary to increase the numerical aperture (NA) of the optical system and shorten the exposure wavelength. It is planned.

[0003] In addition, a conventional scanning exposure apparatus of the same magnification using a catoptric projection optical system is improved, and a refraction element is incorporated in the projection optical system and a combination of a reflection element and a refraction element or only a refraction element is used. Using the configured reduction projection optical system,
A scanning exposure apparatus that synchronously scans both a mask stage and a stage of a photosensitive substrate (wafer stage) at a speed ratio corresponding to a reduction magnification has also attracted attention.

FIG. 8 shows an example of this scanning exposure apparatus. A mask 1 on which an original image is drawn is supported by a mask stage 4, and a wafer 3 as a photosensitive substrate is supported by a wafer stage 5. The mask 1 and the wafer 3 are placed at optically conjugate positions via the projection optical system 2, and a slit-like exposure light 6 extending in the Y direction in the figure from an illumination system (not shown) illuminates the mask 1 and projects it. An image is formed on the wafer 3 at a size corresponding to the projection magnification of the exposure system 2. In the scanning exposure, the mask 1 and the wafer 3 are scanned by moving both the mask stage 4 and the wafer stage 5 with respect to the projection optical system 2 in the X direction at a speed ratio corresponding to the optical magnification. Device pattern 21 on the mask 3
The entire surface is transferred to a transfer area on the wafer 3.

[0005]

In order to perform the scanning exposure, it is necessary to scan the mask 1 and the wafer 3 while always accurately aligning them. Therefore, the following must be performed: 1. Axis alignment and position alignment between the mask stage and the wafer stage. 2. Detection of the distance between the drawing position and the alignment position (baseline correction).

Therefore, conventionally, the following method has been adopted.
That is, a plurality of alignment marks 41 are arranged on the mask 1 as shown in FIG. 8, and the alignment marks 42 are also arranged at corresponding positions on the wafer stage.
The two stages are driven, and the alignment mark of the mask and the wafer is detected at each position by the observation microscope 7, and the positional error between the mask and the wafer stage is measured. As a result, correction is made so that the running of the wafer stage matches the running of the mask.

After the alignment between the mask and the wafer stage, the base line is corrected by measuring the distance between the drawing center position and the position detected by the alignment detection system.

At this time, in order to eliminate a patterning error for each mask, it is desirable in terms of accuracy to provide a reference mask and use one of the reference masks.

However, using the reference mask (a) requires loading this reference mask into the apparatus for each lot and periodically, which affects the throughput. (A) Mask management is a burden. And other problems.

Therefore, a method of patterning the alignment mark on a product mask has been adopted. However, (a) a plurality of mark-dedicated areas are required. (A) Each time a mask is loaded into the apparatus, the above corrections 1 and 2 are required, which affects throughput. And other problems.

[0011]

According to an aspect of the present invention, there is provided an exposure method for solving the above-mentioned problems, in which a first movable stage for mounting and moving a first object and a second object are mounted. A second movable stage that is placed and moved, a first reference plate fixedly provided on the first movable stage, and having a plurality of alignment marks formed thereon, and a plurality of fixed reference marks formed on the second movable stage. A second reference plate on which an alignment mark is formed, wherein the first and second movable stages are scanned in synchronization with a projection optical system and formed on the first object via the projection optical system. A plurality of alignment marks on the first reference plate and a plurality of alignment marks on the second reference plate via the projection optical system. Relative position A first detection step of detecting an engagement and detecting a relationship between a coordinate system defined by a plurality of alignment marks on the first reference plate and a coordinate system defined by a plurality of alignment marks on the second reference plate; Moving the first movable stage in the scanning exposure direction, detecting the positions of the plurality of alignment marks on the first reference plate, and determining a coordinate system determined by the plurality of alignment marks on the second reference plate. A second detection step of detecting a relationship between the first movable stage and a coordinate system defined by an actual scanning direction of the first movable stage; and moving the second movable stage in a scanning exposure direction to form a plurality of movable units on the second reference plate. The position of the alignment mark is detected, and a coordinate system determined by the plurality of alignment marks on the second reference plate and an actual scanning method of the second movable stage. Based on the results of the first, second, and third detection steps, and the actual scanning direction of the first movable stage and the second movable stage based on the results of the first, second, and third detection steps. And a step of determining a relationship with the actual scanning direction.

A relative positional relationship between a plurality of alignment marks formed on the first object and a plurality of alignment marks on the first reference plate is detected, and a plurality of alignment marks on the first reference plate are detected. A fourth detection step of detecting a relationship between a coordinate system defined by the alignment marks and a coordinate system defined by the plurality of alignment marks of the first object.

The method may further include a step of correcting a scanning direction of the first movable stage based on a result of the fourth detecting step.

The method may further include a step of rotating the first object with respect to the first movable stage based on a result of the fourth detection step.

A relative positional relationship between a plurality of alignment marks on the one reference plate and a plurality of alignment marks on a third reference plate fixed to a holding member for holding the projection optical system is detected. A coordinate system defined by a plurality of alignment marks on the first reference plate;
A fifth detection step of detecting a relationship with a coordinate system determined by a plurality of alignment marks on the reference plate;
A plurality of alignment marks formed on the object and the third alignment mark;
A relative positional relationship with a plurality of alignment marks on the reference plate is detected, and a coordinate system determined by the plurality of alignment marks on the first reference plate and a plurality of alignment marks on the third reference plate are used. And a sixth detecting step of detecting a relationship with the determined coordinate system.

Based on the results of the fifth and sixth detection steps,
A step of correcting a scanning direction of the first movable stage.

Based on the results of the fifth and sixth detection steps,
A step of rotating the first object with respect to the first movable stage.

A step of correcting a scanning direction of at least one of the first and second movable stages based on a relationship between an actual moving direction of the first movable stage and an actual moving direction of the second movable stage. It is characterized by having.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 shows a first embodiment of a scanning exposure apparatus according to the present invention. FIG. 5 shows the flow, and FIGS. 6 and 7 are explanatory diagrams of the flow.

In FIG. 1, a mask 1 on which an original image is drawn is placed on a mask stage 4 which is driven and controlled in the X and Y directions by a laser interferometer 80 and a drive control means 103. It is supported by the illustrated apparatus main body. The wafer 3, which is a photosensitive substrate, is placed on a wafer stage 5 that is driven and controlled in the X and Y directions by a laser interferometer 81 and a drive control unit 103, and the wafer stage 5 is supported by an apparatus main body (not shown). . The mask 1 and the wafer 3 are placed at optically conjugate positions via the projection optical system 2, and a slit-like exposure light 6 extending in the Y direction in the figure from an illumination system (not shown) illuminates the mask 1. Then, an image is formed on the wafer 3 with a size corresponding to the projection magnification of the projection exposure system 2. The scanning exposure is performed by using the mask stage 4 and the wafer stage 5 for the slit exposure light 6.
Are moved in the X direction at a speed ratio corresponding to the optical magnification to scan the mask 1 and the wafer 3, and the entire device pattern 21 on the mask 3 is transferred to the transfer region (pattern region) 22 Transcribe.

The method of matching the scanning direction of the mask stage with the scanning direction of the wafer stage, that is, by detecting the relationship between the coordinate system defined by the actual scanning direction of the mask stage and the coordinate system defined by the actual scanning direction of the wafer stage. A method for matching the scanning direction of the mask stage with the scanning direction of the wafer stage will be described below.

A mask reference plate 10 (or 11) shown in FIG. 2 is fixed on the mask stage, and a wafer reference plate 12 shown in FIG. 3 is fixed on the wafer stage. .

On the mask reference plate 10 (or 11), marks 50 (a), 50 (b), 51 (a) and 51 (b) are arranged at the same height as the pattern surface of the mask 1. And a mark 60 on the wafer reference plate 12 corresponding to this position.
(a), 60 (b), 61 (a), 61 (b) are arranged. Each mark is formed on each plate based on a designed coordinate system, and the relative positional relationship is known.

(Step 1) Marks 60 (a) and 60 (b) on the wafer reference plate 12 (or 61 (a) and 61 (b))
Is driven to an observation position (exposure position) below the projection optical system 2 to be stopped. Mask reference plate 10 on mask stage 4
The marks 50 (a) and 50 (b) (or 51 (a) and 51 (b)) on (or 11) are also driven to the exposure position and stopped. Both marks (60 (a), 60 (b), 50 (a), 5 (a),
The relative positional relationship of 0 (b)) is measured. The measured value is a relative value between the wafer reference plate 12 and the wafer reference plate 12.
XY position (XY origin) alignment. That is, the projection optical system 2
, The relative positional relationship between the plurality of alignment marks on the mask reference plate 10 and the plurality of alignment marks on the wafer reference plate 12 is detected, and is determined by the plurality of alignment marks on the mask reference plate 10. A relationship between the coordinate system and a coordinate system determined by a plurality of alignment marks on the wafer reference plate 12 is detected.

(Step 2-1) As shown in FIG. 6A, the marks 60 (a), 60 on the wafer reference plate 12 are formed.
(b) is stopped, and the positions of the marks 50 (a) and 50 (b) on the mask reference plate 10 with respect to the marks 60 (a) and 60 (b) are measured by the microscope 7; Are scanned, and the positions of the marks 51 (a) and 51 (b) on the mask reference plate 10 with respect to the marks 60 (a) and 60 (b) are measured by the microscope 7. Thereby, the marks 50 (a) and 51 (a) on the mask reference plate 10 in the scanning direction (X direction) of the mask stage 4 (or the marks 50 (b) and 51 (b)).
Is detected in parallel with the axis formed by. That is, the coordinate system determined by a plurality of alignment marks on the mask reference plate and the actual scanning direction of the mask stage (X direction)
To detect the relationship with the coordinate system defined by.

(Step 2-2) As shown in FIG. 6B, the marks 50 (a), 50 on the mask reference plate 10
(b) is stopped, and the positions of the marks 60 (a) and 60 (b) on the wafer reference plate 12 with respect to the marks 50 (a) and 50 (b) are measured by the microscope 7, and only the wafer stage 5 is Are scanned, and the positions of the marks 61 (a) and 61 (b) on the wafer reference plate 12 with respect to the marks 50 (a) and 50 (b) are measured by the microscope 7. As a result, the marks 60 (a) and 61 (a) on the wafer reference plate 12 with respect to the scanning direction (X direction) of the wafer stage 5 (or the marks 60 (b) and 61 (b)).
Is detected in parallel with the axis formed by. That is, the coordinate system determined by a plurality of alignment marks on the wafer reference plate and the actual scanning direction of the wafer stage (X direction)
To detect the relationship with the coordinate system defined by.

(Step 3-1) As shown in FIG. 7, the marks 50 (a) and 50 (b) on the mask reference plate 10 are stopped, and the wafer reference plate corresponding to the mark 50 (a), The position of the mark 60 (a) on 12 is measured by the microscope 7,
Only the wafer stage 5 is scanned, and the position of the mark 60 (a) on the wafer reference plate 12 with respect to the mark 50 (b) is measured by the microscope 7. Thereby, the parallelism of the axis formed by the marks 50 (a) and 50 (b) on the mask reference plate 10 with respect to the step direction (Y direction) of the wafer stage 5 is detected. That is, the relationship between the coordinate system determined by the plurality of alignment marks on the mask reference plate and the coordinate system determined by the actual scanning direction (Y direction) of the wafer stage is detected.

(Step 3-2) In the same manner as above,
The marks 60 (a) and 60 (b) on the wafer reference plate 12 are stopped, and the position of the mark 50 (a) on the mask reference plate 10 with respect to the mark 60 (a) is measured by the microscope 7. ,
Only the mask stage 4 is scanned, and the position of the mark 50 (a) on the mask reference plate 10 with respect to the mark 60 (b) is measured by the microscope 7. Thereby, the parallelism between the marks 60 (a) and 60 (b) formed on the wafer reference plate 10 with respect to the step direction (Y direction) of the mask stage 4 is detected. That is, the relationship between the coordinate system determined by the plurality of alignment marks on the wafer reference plate and the coordinate system determined by the actual scanning direction (Y direction) of the mask stage is detected. From the above, (1) a coordinate system determined by a plurality of alignment marks on the mask reference plate 10 and the wafer reference plate 12
(2) Relationship between the coordinate system defined by the plurality of alignment marks on the mask reference plate and the coordinate system determined by the actual scanning direction (X direction) of the mask stage (3) Relationship between a coordinate system determined by a plurality of alignment marks on the wafer reference plate and a coordinate system determined by the actual scanning direction (X direction) of the wafer stage (4) By a plurality of alignment marks on the mask reference plate Relationship between the coordinate system determined and the coordinate system determined by the actual scanning direction (Y direction) of the wafer stage (5) The coordinate system determined by a plurality of alignment marks on the wafer reference plate and the actual scanning direction of the mask stage (Y direction) The relationship with the coordinate system defined by) is detected.

From (1), (2) and (3), the coordinate system determined by the actual scanning direction (X direction) of the mask stage and the coordinate system determined by the actual scanning direction (X direction) of the wafer stage And at least one of the scanning directions of the wafer stage and the mask stage is corrected so that the actual scanning direction of the mask stage (X direction) matches the actual scanning direction of the wafer stage (X direction). .

Further, from (4) and (5), the deviation of the orthogonality of the actual scanning direction in the Y direction with respect to the actual scanning direction in the X direction of the wafer stage is detected, and the Y direction of the wafer stage is eliminated so as to eliminate the deviation. Is detected, the deviation of the orthogonality of the actual scanning direction in the Y direction from the actual scanning direction in the X direction of the mask stage is detected, and the scanning direction in the Y direction of the mask stage is corrected so that the deviation is eliminated. .

As an actual scanning type exposure apparatus, a mask 1
Exposure is performed after relative positioning of the wafer and the wafer 3, so that the coordinate system of the mask and the wafer must be added to the above coordinate system.

In order to take the coordinates of the mask 1 into account, the relative positions of the mask 1 and the mask reference plate 10 are measured.

First, the mask alignment marks 40 (a) and 40 (b) on the mask reference plate 10 are observed with the observation microscope 7, and the respective mark positions are detected. The mask alignment marks 42 (a) and 42 (b) arranged on the mask 1 by driving the mask stage 4 are observed by the observation microscope 7.
To observe and detect the position of each mark.

The driving amount of the mask stage 4 is obtained by the laser interferometer 80, and the positional information (position shift amount) between the mask 1 and the mask reference plate 10 is calculated by the arithmetic processing circuit 102 in accordance with the position information of both marks. Is done. The scanning direction of the mask 1 and the running of the mask stage 6 are made to match based on the calculation result. That is, the mask 1 is rotated with respect to the mask stage 4. Or, mask stage 4
Drive control means 10 so that the scanning direction of the mask 1 matches the scanning direction of the mask 1 with the scanning direction of the mask stage 4.
3, the scanning direction of the mask stage 6 may be controlled. In this case, the scanning direction of the wafer stage 5 is changed and controlled accordingly.

Next, alignment of the wafer 3 with respect to the wafer stage 5 is performed.

In order to determine the distance between the exposure / drawing center and the detection position of the wafer alignment detection system (referred to as a base line),
The mark 55 on the stage reference plate 12 is driven to the center of exposure and drawing, and from this position the same mark 55 is driven below the off-axis microscope 31 to detect the mark position.

As a result, the detection position of the off-axis microscope 31 with respect to the exposure / drawing center is obtained. Then, the positioning of the wafer 3 is performed by the global alignment method.

That is, a plurality of chips to be measured are extracted from the chips on the wafer 3, and the alignment marks therein are detected by the off-axis microscope 31. From the detected position of each mark and the driving amount of the wafer stage measured by the laser interferometer 81, the position of the wafer 3 is calculated by the arithmetic processing circuit 1.
02 is calculated.

As described above, the coordinate system defined by the scanning directions of the mask stage 4 and the wafer stage 5 is made coincident, and the scanning direction of each stage is made coincident with the direction in which the mask 1 and the wafer 3 are to be scanned. I do. The above process is shown in FIG.
Shown in

(Embodiment 2) FIG. 4 shows Embodiment 2 of the present invention. In this embodiment, the positioning of the mask 1 is performed by fixing a fixed reference plate to a holding member for holding the projection optical system 2 and using marks 75 (a) and 75 (b) formed on the reference plate. It was made.

In advance, the mask stage 4 is moved to move the marks 50 (a) and 50 (b) on the mask reference plate 10 onto the marks 75 (a) and 75 (b) on the reference plate, and the reticle alignment microscope 8, both marks (50 (a),
The relative positional relationship between 50 (b), 75 (a), and 75 (b) is measured. Then, a relative positional relationship between the plurality of alignment marks on the mask reference plate 10 and the plurality of alignment marks on the fixed reference plate is detected, and a coordinate system determined by the plurality of alignment marks on the mask reference plate 10 is obtained. A relationship with a coordinate system determined by a plurality of alignment marks on the fixed reference plate is detected in advance. However, marks 75 (a) and 75 (b) on the fixed reference plate and marks 50 (a) and 50 (a) on the mask reference plate 10 (or 11)
The measurement of the positional relationship such as (b) does not need to be performed every time the mask is replaced if the positions of the marks 75 (a) and 75 (b) on the fixed reference plate are stable.

The mask stage is moved and the mask alignment marks 42 (a) and 42 (b) on the mask are marked 75.
(a) and 75 (b). The mask is replaced in this location.

Then, the relative positional relationship between the two marks (42 (a), 42 (b), 75 (a), 75 (b)) is measured by the reticle alignment microscope 8. Then, a relative positional relationship between the plurality of alignment marks on the mask 4 and the plurality of alignment marks on the fixed reference plate is detected, and a coordinate system determined by the plurality of alignment marks on the mask 4 and a fixed reference plate are detected. The relationship between the coordinate system determined by the plurality of alignment marks above is detected, and the detection result and the coordinate system determined by the plurality of alignment marks on the mask reference plate 10 and the plurality of alignments on the fixed reference plate are obtained in advance. The mask 1 is rotated with respect to the mask stage 4 in consideration of the relationship with the coordinate system determined by the mark. Alternatively, the scanning direction of the mask stage 6 is controlled by the drive control means 103 so that the scanning direction of the mask stage 4 matches the scanning direction of the mask stage 4 with the scanning direction of the mask 1.

The marks 75 (a) on the reference plate,
75 (b) is replaced with the mask alignment marks 42 (a), 42 on the mask stage when the mask is located at the exposure position.
The above effect can be obtained even if provided under (b).

That is, the mask stage is moved to
The mask alignment is performed by placing 2 (a) and 42 (b) (or marks 75 (a) and 75 (b)) at the observation position of the reticle alignment microscope 8. The mark 75 (a) at this time,
The positional relationship between the mark 75 (b) and the marks 50 (a), 50 (b) can be measured by the microscope 7 or the reticle alignment microscope 8 with the mask mounted. The measurement of this positional relationship also includes the mark 75 (a) on the fixed reference plate,
If the position of 75 (b) is stable, it is not necessary to carry out each time the mask is replaced.

The other steps are the same as in the first embodiment. Next, an embodiment of a device production method using the above-described exposure method will be described.

FIG. 9 shows a flow of manufacturing micro devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, etc.). Step 1
In (circuit design), a circuit of a semiconductor device is designed.
Step 2 is a process for making a mask on the basis of the circuit pattern design. On the other hand, in step 3 (wafer manufacturing), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process,
An actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 10 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of this embodiment, it is possible to manufacture a highly integrated semiconductor device, which has been conventionally difficult to manufacture, at low cost.

[0050]

As described above, according to the present invention, the mask reference plate is arranged on the mask stage, the mark and the mark on the wafer reference plate on the wafer stage are detected by a microscope, and the relative position is measured. Even if there is no reference mask, the alignment between the mask and the wafer can be made possible.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main part of a first embodiment of the present invention.

FIG. 2 is a mask reference plate of the present invention.

FIG. 3 is a wafer reference plate of the present invention.

FIG. 4 is a schematic diagram of a main part of a second embodiment of the present invention.

FIG. 5 is a flowchart of an embodiment of the present invention.

FIG. 6 is an explanatory diagram of the flow of the present invention.

FIG. 7 is an explanatory diagram of the flow of the present invention.

FIG. 8 is a schematic diagram of a main part of the related art.

FIG. 9 is a semiconductor device manufacturing flow.

FIG. 10 is an explanatory diagram for a wafer process.

[Explanation of symbols]

 Reference Signs List 1 mask 2 projection optical system 3 wafer 4 mask stage 5 wafer stage 6 exposure light slit 7 observation microscope 8 reticle alignment microscope 10, 11 mask reference plate 12 wafer reference plate 31 off-axis observation microscope 42 mask alignment mark 50, 51 mask Alignment mark on reference plate 60, 61 Alignment mark on wafer reference plate 80, 81 Laser interferometer

Claims (9)

[Claims] A first movable stage for mounting and moving a first object, a second movable stage for mounting and moving a second object, and a plurality of fixed stages mounted on the first movable stage; A first reference plate having alignment marks formed thereon, and a second reference plate fixedly provided on the second movable stage and having a plurality of alignment marks formed thereon, wherein the first and second movable stages are provided. Scanning in synchronization with the projection optical system and projecting a pattern formed on the first object onto a second object via the projection optical system, A relative positional relationship between the plurality of alignment marks on the first reference plate and the plurality of alignment marks on the second reference plate is detected, and is determined by the plurality of alignment marks on the first reference plate. Ma A first detection step of detecting a relationship between a coordinate system and a coordinate system defined by a plurality of alignment marks on the second reference plate; and moving the first movable stage in a scanning exposure direction, Detecting the positions of the plurality of alignment marks above and detecting the relationship between the coordinate system determined by the plurality of alignment marks on the second reference plate and the coordinate system determined by the actual scanning direction of the first movable stage. Moving the second movable stage in the scanning exposure direction to detect the positions of a plurality of alignment marks on the second reference plate, and detecting a plurality of positions on the second reference plate. A third detection step of detecting a relationship between a coordinate system determined by an alignment mark and a coordinate system determined by an actual scanning direction of the second movable stage; the first, second, and third detections A scanning type exposure method comprising: determining a relationship between an actual scanning direction of the first movable stage and an actual scanning direction of the second movable stage based on a result of the step. 2. Detecting a relative positional relationship between a plurality of alignment marks formed on the first object and a plurality of alignment marks on the first reference plate, and detecting the relative positional relationship between the plurality of alignment marks on the first reference plate. 2. The scanning exposure method according to claim 1, further comprising a fourth detection step of detecting a relationship between a coordinate system defined by a plurality of alignment marks and a coordinate system defined by a plurality of alignment marks of the first object. 3. The scanning exposure method according to claim 2, further comprising a step of correcting a scanning direction of said first movable stage based on a result of said fourth detection step. 4. The scanning exposure method according to claim 2, further comprising a step of rotating the first object with respect to the first movable stage based on a result of the fourth detection step. 5. A relative positional relationship between a plurality of alignment marks on the one reference plate and a plurality of alignment marks on a third reference plate fixed to a holding member for holding the projection optical system. A fifth detecting step of detecting a relationship between a coordinate system defined by a plurality of alignment marks on the first reference plate and a coordinate system defined by a plurality of alignment marks on the third reference plate; A relative positional relationship between a plurality of alignment marks formed on one object and a plurality of alignment marks on the third reference plate is detected, and is determined by the plurality of alignment marks on the first reference plate. 6. A sixth detecting step for detecting a relationship between a coordinate system and a coordinate system defined by a plurality of alignment marks on the third reference plate. Scanning exposure method. 6. The scanning exposure method according to claim 5, further comprising the step of correcting a scanning direction of said first movable stage based on a result of said fifth and sixth detection steps. 7. The scanning exposure method according to claim 5, further comprising a step of rotating the first object with respect to the first movable stage based on a result of the fifth and sixth detection steps. 8. A scanning direction of at least one of the first and second movable stages is corrected based on a relationship between an actual moving direction of the first movable stage and an actual moving direction of the second movable stage. 8. The scanning exposure method according to claim 1, further comprising a step. 9. A device manufacturing method using the scanning exposure method according to claim 1.