JP2013247325A - Exposure device and method of controlling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a step-and-repeat type exposure device which can prevent in advance occurrence of failure due to misrecognition of a shot of a rough alignment object.SOLUTION: A step-and-repeat type exposure device includes a movable type sample table 14, a sample table control unit 4 performing movement control of the sample table and a main control unit 2 controlling the whole device, and repeatedly performs positioning processing and exposure processing on a sample placed on the sample table 14 by moving an exposure object section in the sample. The exposure device further includes a positioning error detection unit 3 detecting a positioning error in the positioning processing. When an operator manually performs a positioning operation in accordance with occurrence of the positioning error, if the sample table 14 moves in excess of a constant value by the manual operation of the operator with the position of the sample table at the occurrence of the positioning error as a reference, the sample table control unit 4 detects the movement in excess of the constant value, and the sample table control unit 4 or the main control unit 2 performs control to issue a warning indicating the occurrence of the movement in excess of the constant value.

Description

  The present invention relates to a step-and-repeat exposure apparatus that repeatedly performs alignment processing and exposure processing on a sample placed on a movable sample stage by moving an exposure target section in the sample and a control method thereof About.

  FIG. 2 shows a schematic configuration of an alignment optical system of a general step-and-repeat type reduction projection exposure apparatus. As shown in FIG. 2, the alignment optical system of the reduction projection exposure apparatus includes a reticle alignment optical system and a wafer alignment optical system. In the reticle alignment optical system, reticle alignment microscopes RX, RY, Rθ are arranged above the reticle 11, and in the wafer alignment optical system, an off-axis optical wafer alignment microscope WY, Wafer alignment sensors SX and SY composed of a laser alignment sensor or optical image alignment sensor of Wθ and TTL (Through the Lens) optical system, and an automatic focus detector 13 are arranged, and are movable below the reduction projection lens 12. A wafer stage 14 of the type is arranged. Note that ITV in FIG. 2 is an industrial camera for capturing a processing object.

  The alignment and exposure processing method of the step-and-repeat type exposure apparatus having the configuration shown in FIG. 2 will be described with reference to FIGS. FIG. 3 is a flowchart showing a schematic alignment procedure of the exposure apparatus, FIG. 4 is a flowchart showing a processing procedure of reticle alignment (S10) in FIG. 3, and FIG. 5 is a wafer alignment in FIG. It is a flowchart which shows the process sequence of (S20).

  First, the reticle alignment (S10) shown in FIG. 3 is automatically performed while the reticle 11 is loaded on a reticle table (not shown) of the exposure apparatus and the wafer 15 coated with the photosensitive film is supported on the wafer stage. After performing the rough alignment (S22) and fine alignment (S23) of the wafer alignment (S20) and completing the reticle alignment (S10) and the wafer alignment (S20), an exposure process is performed.

  The procedure of reticle alignment (S10) will be described with reference to FIG. First, a reticle alignment mark (not shown) of the reticle 11 is roughly searched, and when the reticle alignment mark search is completed, the reticle 11 is set to the parking position for setting the next reticle alignment microscope RX, RY, Rθ. Position (S11).

  Next, the position of each reticle alignment microscope is detected by moving the reference mark provided on the wafer stage 14 to the lower side of each reticle alignment microscope and decoding the position of the wafer stage 14. At this time, since the reticle alignment microscope needs to be set parallel to the X-axis traveling of the wafer stage 14, the reference mark is aligned with the reticle alignment microscope before the reference mark is moved. The optical axis is corrected by using a parallel plate glass (not shown) so as to move the reticle alignment mark by a distance corresponding to the interval between the reticle alignment marks and to align the reticle alignment microscope with the reference mark. Thereby, the coordinates of the X axis and the Y axis of the reticle alignment microscopes RX, RY, Rθ are determined (S12).

  Next, the reticle 11 is aligned with respect to the reticle alignment microscope whose position has been detected. That is, alignment of X, Y, and θ is performed using three types of reticle alignment marks (Rmx, Rmy, and Rmθ) of X, Y, and θ of the reticle l. At this time, the reticle alignment marks RX, RY, Rθ are simultaneously used to track the reticle alignment mark and align it in the normal position (S13).

  When the alignment in the previous step (S13) is completed, the position of the reticle 11 is measured using the reference mark, the position of the reticle alignment mark (Rmx, Rmθ) is measured, and the amount of rotation of the reticle l is determined. The alignment check is performed by comparing the rotation amount of the reticle 11 with an allowable value (S14). If the amount of rotation is not less than the allowable value (No branch in S15), the optical axis of the reticle alignment microscope (Rθ) is corrected with the amount of rotation, and the process returns to step S13, where the amount of rotation is less than the allowable value. If yes (Yes in S15), the positions of the wafer alignment sensors SX and SY are checked (S16).

  Next, the positions of the alignment marks formed on the reference marks are obtained, and the positions of the wafer alignment microscopes WY and Wθ are measured. In this case, the position of the microscope is obtained by decoding the coordinates of the wafer stage 9 (S17).

  By the above procedure, the reticle 11 is aligned by the reticle alignment microscope, and as a result of the alignment, the relative position between the wafer alignment sensor and each wafer alignment microscope is obtained, and the result is used as the next wafer alignment (S20). Used in.

  Next, the wafer alignment (S20) processing procedure will be described with reference to FIG. First, in a state where the wafer 15 pre-aligned by the pre-alignment unit of the wafer loader is loaded on the wafer stage 14, it is determined whether or not the exposure is performed by superimposing the wafer 15 on the underlayer by wafer alignment (S21). As a result of the determination, if it is determined that the alignment exposure is not performed (No branch of S21), the step-and-repeat exposure of the first layer is performed (S27), and if it is determined that the alignment exposure is performed (S21). Yes branch), coarse alignment is performed to determine the X-axis coordinate and Y-axis coordinate of the wafer (S22).

  The rough alignment will be described in more detail. The wafer 15 loaded on the wafer stage 14 is automatically focused by the automatic focus detector 13, and the rough alignment marks (Wmy, Wmθ) on the wafer 15 are placed on the wafer alignment microscope WY. , Wθ is moved downward. At this time, since the wafer alignment microscopes WY and Wθ are already positioned parallel to the running direction of the wafer stage 14, the wafer alignment microscopes WY and Wθ are used to detect the coarse alignment marks (Wmy, Wmθ). By aligning, the Y-axis coordinate of the wafer 15 is determined, and by performing alignment in the X-axis direction using the wafer alignment sensor SX, the X-axis coordinate and the Y-axis coordinate of the wafer 15 are determined. The

  Subsequently, fine alignment is performed (S23). That is, by using the wafer alignment sensors SX and SY for a plurality of designated shots to be aligned, an X coordinate position detection mark and a Y coordinate position detection mark (X coordinate position detection mark and Y The coordinate position detection mark may be a dual-purpose mark), and the following four types of correction values are calculated from the measurement results of each shot. The shot exposure position is determined by continuously referring to the calculated correction value during step-and-repeat exposure. In this specification, “shot” means a processing unit partitioned on the wafer 15 in alignment and exposure processing.

1) Offset correction values in X and Y directions When an offset exists between the shot position obtained from the rough alignment (S22) and the position obtained from the measurement of the wafer alignment sensor, the offset value is obtained from the calculation result. .

2) Wafer rotation correction value A wafer that has undergone Y-θ alignment does not inherently rotate. However, the amount of rotation of the wafer is obtained from the calculation result in consideration of an error factor due to defocusing or the like.

3) X and Y direction scaling correction values These are correction values for correcting the expansion and contraction of the wafer. For example, when correction values of a (ppm) in the X direction and b (ppm) in the Y direction are obtained from the measurement result of the wafer alignment sensor, the coordinates (x, y) of the shot position calculated from the exposure map are used. The exposure is actually corrected for scaling. Here, when the corrected position coordinates are (X, Y), the following relationship is established.
X = (1 + a × 10 ⁻⁶ ) × x (mm)
Y = (1 + b × 10 ⁻⁶ ) × y (mm)

4) X and Y axis orthogonality correction values These are correction values for exposing a wafer in accordance with the orthogonality of the array. A correction value of the orthogonality is obtained from the calculation result.

  Next, it is determined whether to perform die by die alignment exposure during step-and-repeat exposure (S24). If it is determined that the die-by-die alignment exposure is to be performed (Yes branch of S24), the position of the X coordinate position detection mark and the Y coordinate position detection mark before each exposure shot of the wafer 15 is performed. After performing alignment for determining the exposure position by calculating a correction value based on the result of the measurement, step-and-repeat exposure is performed (S25). If it is determined that die-by-die alignment exposure is not performed (No branch of S24), step-and-repeat exposure is performed on the wafer 15 without performing the alignment in each exposure shot (S26).

Japanese Patent Laid-Open No. 10-242044

  However, following a plurality of alignment and exposure processes and subsequent processing steps such as film formation and etching, due to deformation of alignment marks used in the next step formed in the processing step and defects in the processing processing, There may be a case where the alignment mark cannot be identified. That is, for example, even if coarse alignment marks are formed at three locations on the wafer 15, automatic coarse alignment using the rough alignment marks at the three locations cannot be executed in the next process, and an error occurs. There is a case.

  When the rough alignment error occurs, the operator directly searches for a rough alignment shot while looking at the monitor screen, and manually performs rough alignment using the rough alignment mark. When manual rough alignment is normally performed, as shown in FIG. 6A, shots 16 on the same horizontal line of the wafer 15, for example, 10 shots are all exposed.

  However, since all the shots on the wafer 15 have the same coarse alignment mark, the operator misidentifies other shots instead of the coarse alignment target shots as the rough alignment target shots, and performs manual rough alignment. In some cases, alignment was performed. For example, when the operator mistakes the left shot of the shot for coarse alignment as a shot for coarse alignment and manually performs coarse alignment, all the shots 16 on the same horizontal line of the wafer 15 are normally exposed. I can't. That is, as shown in FIG. 6B, in the leftmost shot, only a partial area in the wafer at the left end of the wafer 15 is exposed, and the other part is exposed in a space other than the wafer 15. . Here, when the position information obtained by manual rough alignment is taken into the equipment side and the sample stage is to be controlled, the processing in the adjacent shot is processed based on erroneous information. In addition, a phenomenon similar to the above also occurs when a lower shot of the original shot is mistaken as a rough alignment target shot.

  If an operator mistakenly recognizes a rough alignment target shot while performing rough alignment manually, the exposure process may be reworked or the wafer itself may be discarded, resulting in decreased productivity and increased production costs. It was.

  The present invention has been made in view of the above problems, and an object thereof is a step-and-repeat type exposure apparatus and a control method thereof that can prevent the occurrence of problems caused by misidentifying a shot to be roughly aligned. Is to provide

  In order to achieve the above object, the present invention includes a movable sample stage, a sample stage control unit that controls movement of the sample stage, and a main control unit that controls the entire apparatus, and is placed on the sample stage. A step-and-repeat exposure apparatus that repeatedly performs alignment processing and exposure processing on a sample that has been moved by moving an exposure target section in the sample, and a position for detecting a positioning error in the alignment processing An alignment error detection unit is provided, and when the operator manually performs an alignment operation with the occurrence of the alignment error, the operator's position is determined based on the position of the sample stage when the alignment error occurs. When the sample stage moves beyond a certain value by manual operation, the sample stage control unit detects a movement exceeding the certain value, and the sample stage control unit or the main control unit moves beyond the certain value. To provide an exposure apparatus and performing control for generating an alarm indicating the occurrence.

  Further, in the exposure apparatus having the above characteristics, when the main control unit receives the alignment error detection signal from the alignment error detection unit, the sample stage control unit provides information on the movement interval of the exposure target section. It is preferable to become effective.

  Furthermore, in order to achieve the above object, the present invention is a step-and-step method in which alignment processing and exposure processing are repeatedly performed on a sample placed on a movable sample stage by moving the exposure target section in the sample. A repeat-type exposure apparatus control method, wherein when an alignment error occurs in the alignment process, the alignment error is detected, and an operator manually performs an alignment operation when the alignment error occurs. When performing, on the basis of the position of the sample stage when the alignment error occurs, when the sample stage moves beyond a certain value by manual operation of the operator, the movement exceeding the certain value is detected, Provided is a control method for an exposure apparatus, characterized in that control for generating an alarm indicating the occurrence of movement exceeding the certain value is performed.

  Furthermore, in the method for controlling an exposure apparatus having the above characteristics, it is preferable that information on the movement interval of the exposure target section is valid when the operator manually performs a positioning operation.

  Further, in the exposure apparatus and the control method therefor described above, it is preferable that the constant value is set to be less than or equal to one half of the movement interval of the exposure target section.

  Furthermore, in the exposure apparatus having the above characteristics and its control method, it is preferable that when the movement exceeding the predetermined value is detected, the movement control of the sample stage by the manual operation of the operator is invalidated.

  Furthermore, in the exposure apparatus having the above characteristics and its control method, it is preferable that the alarm is output by at least one of light emission and sound generation.

  According to the exposure apparatus having the above characteristics and its control method, when an error occurs in the alignment process (alignment) automatically performed by the exposure apparatus, the position of the sample stage when the error occurs is originally manually aligned. When the movement of the sample table by the manual operation is detected to move beyond a certain value based on the position of the sample table, the operator misidentifies the shot to be aligned. By generating an alarm by the detection, it is possible to notify the worker that the shot to be aligned is misidentified, and while misidentifying the shot to be aligned, It is possible to prevent the subsequent processing from continuing. As a result, problems such as reworking the exposure process or discarding the wafer itself can be solved. The shot corresponds to “exposure target section”.

  Here, when the information regarding the movement interval of the exposure target section becomes invalid due to the manual alignment operation performed by the operator due to the occurrence of the alignment error, processing for validating the information is performed. Thus, it is possible to reliably detect that the movement of the sample stage by the manual operation exceeds a certain value with reference to the position of the sample stage.

  Further, by setting the constant value to be less than or equal to one half of the movement interval of the exposure target section, the movement of the sample stage by the manual operation exceeds a certain value with reference to the position of the sample stage when an error occurs. If it is detected that a large position deviation has already occurred before entering the manual alignment process, it can be determined that the operator misidentifies the shot to be aligned.

  Furthermore, when a movement exceeding the certain value is detected, the movement of the sample stage by the manual operation of the operator is invalidated, so that even if the operator is not aware of the alarm, It is possible to prevent the subsequent processing from being performed continuously while misidentifying the shot.

1 is a system configuration diagram schematically showing a schematic system configuration of a step-and-repeat exposure apparatus according to the present invention. The figure which shows schematic structure of the alignment optical system of a general step-and-repeat type reduction projection exposure apparatus A flowchart showing a schematic alignment procedure of a general step-and-repeat type exposure apparatus The flowchart which shows the process sequence of the reticle alignment (S10) shown in FIG. The flowchart which shows the process sequence of the wafer alignment (S20) of FIG. The figure which illustrates the some shot exposed on the wafer in the general step-and-repeat type exposure process

  Hereinafter, embodiments of a step-and-repeat exposure apparatus and a control method thereof according to the present invention will be described with reference to the drawings.

  FIG. 1 is a system configuration diagram schematically showing a schematic system configuration of an exposure apparatus of the present invention. As shown in FIG. 1, the exposure apparatus of the present invention includes an apparatus body 10 and a controller 1. Since the apparatus main body 10 includes the configuration of the alignment optical system of the general step-and-repeat type reduction projection exposure apparatus illustrated in FIG. 2, the overlapping description is omitted. For the components related to the apparatus main body 10, the same reference numerals are used for the same components as those illustrated in FIG. 2 for convenience of explanation. The configuration of the apparatus main body 10 is not limited to the configuration illustrated in FIG. 2, and various modifications are possible as long as it has a basic function as a step-and-repeat type exposure apparatus.

  As shown in FIG. 1, the control unit 1 includes a main control unit 2, a signal processing unit 3, a sample stage control unit 4, a sample delivery control unit 5, a processing control unit 6, an exposure environment control unit 7, an operator interface 8, The alarm device 9 is provided. In particular, the main control unit 2, the signal processing unit 3, the sample stage control unit 4, and the alarm device 9 constitute a characteristic part of the present invention.

  The main control unit 2 is provided for the purpose of controlling the entire exposure apparatus, and is between the signal processing unit 3, the control units 4 to 7 provided for each control target of the exposure apparatus, and the operator interface 8. Necessary control information is exchanged, and necessary control is performed in a timely manner for each of the control units 4 to 7 and the alarm device 9. The main control unit 2 includes a data storage area (not shown), and information on processing conditions of the sample (wafer) (arrangement information of the coarse alignment mark in the shot, dimensions of each shot, arrangement information in the wafer, etc.) ) Is stored.

  The signal processing unit 3 obtains alignment information from the signal obtained from the apparatus body 10 and the position information of the wafer stage (sample stage) 14 obtained from the sample stage control unit 4 during the alignment (positioning) process, and performs main control. To part 2. In addition, the signal processing unit 3 detects an alignment error during the alignment process when the signal input to the signal processing unit 3 is weak or the signal cannot be determined due to a large noise, and the main control is performed. It functions as an alignment error detection unit that is transmitted to the unit 2.

  The sample stage control unit 4 controls the movement of the wafer stage 14 based on the shot size and arrangement information stored in the main control unit 2. The sample delivery control unit 5 controls the conveyance of the wafer 15 to the wafer stage 14. The process control unit 6 controls a part related to the exposure process of the apparatus main body unit 10. Specifically, magnification control is performed in consideration of the applied energy at the time of exposure and the expansion of the lens due to transmitted energy. Under the control of the main control unit 2, the exposure environment control unit 7 controls the environment such as temperature, humidity, and air current in the apparatus main body unit 10. The basic control contents of the control units 4 to 7 are the same as those of a general step-and-repeat exposure apparatus, and a detailed description thereof is omitted.

  The operator interface 8 is a man-machine interface between the main control unit 2 and the operator. The main control unit 2 starts control of the exposure apparatus from the operator via the operator interface 8. The operator is notified of the status of the exposure apparatus and the like via the operator interface 8. Further, when an alignment error occurs, the main control unit 2 notifies the worker of the occurrence of the error via the worker interface 8. Also, the worker interface 8 receives a manual alignment operation by the worker and transmits the operation content to the main control unit 2. Furthermore, when accepting manual input of information related to the processing conditions described above, an input operation of the information by the worker is accepted and transmitted to the main control unit 2.

  When the operator manually performs an alignment operation due to the occurrence of an alignment error, the alarm device 9 misidentifies a shot to be aligned and abnormally moves the wafer stage 14 in the manner described later. When abnormal movement is detected, an alarm for notifying the worker of the occurrence of the abnormal movement is output by sounding or emitting light. In the case of outputting an alarm by sound, it is preferable to provide a buzzer, a speaker, or the like capable of outputting a sound or a voice message different from the sound generated at the time of the terminal constituting the worker interface 8. In the case of outputting an alarm by light emission, a warning light is provided in the vicinity of the terminal constituting the worker interface 8, or at a predetermined position on the monitor screen of the terminal, the visibility is different from the normal display. It is also preferable to output a warning display using a display pattern or display color. Also, a sound alarm and a light alarm may be used in combination.

  The main control unit 2 of the control unit 1 and the control units 4 to 7 described above cooperate to align the general step-and-repeat reduction projection exposure apparatus described with reference to FIGS. Processing similar to the exposure processing is automatically executed.

  Although overlapping with the above description, each alignment process will be briefly described. In the reticle alignment (S10) of FIG. 3, the reticle alignment mark formed on the reticle 11 placed on the reticle stage (not shown in FIG. 2) is aligned with the reference mark provided on the wafer stage. It is carried out.

  In the coarse alignment (S22) of FIG. 3, information on the processing conditions of the sample (wafer) stored in the main controller 2 (arrangement information of the coarse alignment mark in the shot, dimensions of each shot, arrangement information in the wafer, etc.) Based on the above, approximate positioning of the wafer 15 transferred to the wafer stage 14 is performed.

  In the fine alignment (S23) of FIG. 3, the arrangement state of individual shots formed in the wafer 15 is confirmed. In general, the position of several shots in the plane of the wafer 15 is calculated with respect to the position calculated from the arrangement information in the wafer 15 of each shot stored in the main control unit 2, The tendency of positional deviation is grasped and the positional deviation is corrected. In particular, the positional deviation is also confirmed for each individual shot (die-by-die alignment exposure in FIG. 5).

  If the signal processing unit 3 detects an alignment error based on the determination state of the signal input to the signal processing unit 3 while the rough alignment is automatically performed in the manner described above, the main control unit 2 will indicate that. The automatic processing of coarse alignment is interrupted. The coarse alignment error may occur due to a case where the coarse alignment mark cannot be identified due to deformation of the coarse alignment mark or a defect in processing.

  When the automatic processing of rough alignment is interrupted due to the occurrence of the above error, the operator directly searches for a shot for rough alignment while looking at the monitor screen of the worker interface 8 and uses the rough alignment mark of the shot. Manually perform coarse alignment. At this time, it is premised that the manual rough alignment is normally performed. However, in a general exposure apparatus, the operation of the wafer stage 14 is freely limited as long as it is within the mechanical operation range. 14 positions can be moved. For this reason, the same coarse alignment mark is formed on all shots of the wafer, so that the operator misidentifies other shots (for example, adjacent shots) as the coarse alignment target shots instead of the coarse alignment target shots. In some cases, manual rough lining was performed.

  In general, the sample stage control unit 4 has a position calculation mechanism that recognizes the current position of the wafer stage 14. In this embodiment, when the signal processing unit 3 detects a rough alignment error, the sample stage control unit 4 4 receives the notification of the occurrence of the error transmitted to the main control unit 2 from the main control unit 2, and the current position information of the wafer stage 14 at the time of the error occurrence is provided in the sample stage control unit 4. Save in the storage area. As a result, when the operator misidentifies the shot as a rough alignment target and moves the wafer stage 14 abnormally by manual operation, the sample stage control unit 4 determines the current position of the wafer stage 14 moved by manual operation. Compared with the current position of the wafer stage 14 when the coarse alignment error is retracted in the storage area, the movement distance of the wafer stage 14 in the X direction or Y direction from the coarse alignment error occurrence time is X direction or It is determined whether or not a certain reference value set for the corresponding movement direction in the Y direction has been exceeded, and it is determined whether or not the movement of the wafer stage 14 by manual operation is abnormal.

  In the present embodiment, the fixed reference value in each of the X direction and the Y direction is set to a value that is a half of the arrangement interval (movement interval of the exposure target section) of each shot in the wafer in the X direction and the Y direction. It is set. That is, the absolute value of the movement distance in the ± X direction of the wafer stage 14 by manual operation exceeds the reference value in the X direction (1/2 of the arrangement interval in the X direction) or the absolute value of the movement distance in the ± Y direction. When the value exceeds the reference value in the Y direction (one half of the arrangement interval in the Y direction), it is determined that the movement operation is abnormal.

  In a general step-and-repeat type exposure apparatus, the size of each shot is set within a range of about 15 mm square to 22 mm square, and the movement of the wafer stage 14 exceeding half the arrangement interval is manually performed. It can be determined that a large positional deviation has already occurred before the rough alignment process. In rough alignment processing by manual operation, it is only necessary to realize movement within one-half of the arrangement interval in the positive and negative directions in each of the X and Y directions. For this reason, the constant reference value is set to the arrangement interval of each shot. The value is set to 1/2. The fixed reference value does not need to be exactly equal to a half of the array interval of each shot, and has a certain allowable range (for example, ± 10 to 20% of the array interval of each shot) (About), it may be a value less than or equal to one half of the arrangement interval.

  If the sample stage control unit 4 determines that the movement of the wafer stage 14 by manual operation is abnormal, it notifies the main control unit 2 of the abnormality. When the main control unit 2 receives the notification of the abnormality, the main control unit 2 operates the alarm device 9 and outputs an alarm for notifying the occurrence of the abnormal movement. In other words, the sample stage control unit 4 performs control to operate the alarm device 9 indirectly via the main control unit 2, but directly the alarm device 9 without using the main control unit 2. You may control to operate.

  Here, the sample stage control unit 4 calculates and uses the constant reference value based on the arrangement interval of each shot, but information regarding each shot used in the control in the sample stage control unit 4 is obtained by the rough alignment process. When invalidated before shifting to manual operation, the main control unit 2 does not invalidate the information held by the sample stage control unit 4 or validated when invalidated. To do. That is, in the present embodiment, the information is valid at the time when the rough alignment process shifts to the manual operation. The non-invalidating process or the enabling process may be performed spontaneously by the sample stage control unit 4 when a rough alignment error occurs, and the main control unit 2 again transmits the information to the sample stage control unit 4. It may be performed by transmitting to.

  When the alarm device 9 generates a warning by sound or light, the operator can recognize that the rough alignment target shot is mistaken in the rough alignment processing by his manual operation, and the erroneous rough Before the alignment process is completed, the rough alignment process can be performed again on the correct coarse alignment target shot.

[Another embodiment]
<1> In the above embodiment, when the main control unit 2 receives the notification of the abnormal movement of the wafer stage 14 by manual operation from the sample stage control unit 4, the control is performed to activate the alarm device 9. Instead of or in addition to the operation control 9, the instruction for manual operation of coarse alignment received from the operator interface 8 is invalidated without being transmitted to the sample stage controller 4, and the wafer stage 14 is moved by manual operation. It is also preferable not to further move beyond the certain reference value. Alternatively, even if the sample stage control unit 4 receives the manual operation instruction transmitted from the main control unit 2, the instruction may be invalidated and the movement control of the wafer stage 14 may not be performed.

  <2> In the above embodiment, the control unit 1 includes the main control unit 2, the signal processing unit 3, the sample stage control unit 4, the sample delivery control unit 5, the processing control unit 6, the exposure environment control unit 7, and the operator interface 8. In addition, the configuration in which the control units 4 to 7 are provided for each control target of the exposure apparatus is illustrated with the alarm device 9, but the configuration of the control unit 1 is limited to the configuration of the above embodiment. Instead, each of the control units 4 to 7 may be further subdivided, or a part of the control units may be integrated, and one control unit may control all the control targets of the exposure apparatus. The structure to control may be sufficient.

  <3> In the above embodiment, the case where the present invention is applied to the step-and-repeat type exposure apparatus and the control method thereof has been described. Naturally, as the exposure apparatus, extreme ultraviolet (EUV), X-ray, The present invention can also be applied to an exposure apparatus using a light source (energy source) having a shorter wavelength such as an electron beam. Further, the present invention can be applied not only to the reduced projection exposure but also to the same magnification exposure as long as it is a step-and-repeat type exposure apparatus.

1: Control unit 2: Main control unit 3: Signal processing unit (positioning error detection unit)
4: Sample stage control unit 5: Sample delivery control unit 6: Processing control unit 7: Exposure environment control unit 8: Worker interface 9: Alarm device 10: Device main unit 11: Reticle 12: Reduction projection lens 13: Automatic focus detection 14: Wafer stage (sample stage)
15: Wafer (sample)
16: Shot (exposure target area)

Claims (10)

A movable sample stage, a sample stage control unit that controls movement of the sample stage, and a main control unit that controls the entire apparatus, and alignment processing and exposure for the sample placed on the sample stage A step-and-repeat type exposure apparatus that repeatedly performs processing by moving the exposure target section in the sample,
An alignment error detector for detecting an alignment error in the alignment process;
When the operator manually performs the alignment operation with the occurrence of the alignment error, the sample table is moved manually by the operator based on the position of the sample table when the alignment error occurs. When moving beyond a certain value, the sample table control unit detects movement exceeding the certain value, and the sample table control unit or the main control unit generates an alarm indicating the occurrence of movement exceeding the certain value. An exposure apparatus that performs control.   When the main control unit receives the alignment error detection signal from the alignment error detection unit, information regarding the movement interval of the exposure target section becomes valid in the sample stage control unit. Item 4. The exposure apparatus according to Item 1.   The exposure apparatus according to claim 1, wherein the constant value is set to be less than or equal to a half of a movement interval of the exposure target section.   When the sample stage control unit detects a movement exceeding the predetermined value, the main control unit or the sample stage control unit invalidates the movement control of the sample stage by manual operation of the operator. The exposure apparatus according to any one of claims 1 to 3.   The exposure apparatus according to claim 1, further comprising an alarm device that outputs the alarm by at least one of light emission and sound generation. A control method for a step-and-repeat exposure apparatus that repeatedly performs alignment processing and exposure processing on a sample placed on a movable sample stage by moving an exposure target section in the sample,
When an alignment error occurs in the alignment process, the alignment error is detected,
When the operator manually performs the alignment operation with the occurrence of the alignment error, the sample table is moved manually by the operator based on the position of the sample table when the alignment error occurs. When moving beyond a certain value, the movement exceeding the certain value is detected,
A control method for an exposure apparatus, wherein control is performed to generate an alarm indicating the occurrence of movement exceeding the certain value.   7. The method of controlling an exposure apparatus according to claim 6, wherein when the operator manually performs an alignment operation, information on the movement interval of the exposure target section is valid.   8. The method of controlling an exposure apparatus according to claim 6, wherein the constant value is set to a half or less of a movement interval of the exposure target section.   9. The exposure apparatus control according to claim 6, wherein when the movement exceeding the predetermined value is detected, movement control of the sample stage by manual operation of the operator is invalidated. Method. 10. The method of controlling an exposure apparatus according to claim 6, wherein the alarm is output by at least one of light emission and sound generation.

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