JP2012134205A - Charged particle beam lithography apparatus and charged particle beam lithography method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lithography apparatus capable of irradiating a high-precision drawing position with a beam.SOLUTION: The lithography apparatus 100 comprises a measurement unit 52 which detects a position of a substrate 101 to be drawn, an XY stage 105 on which the substrate is arranged, a relative position operating unit 53 which operates the relative position of the substrate and the stage by using the position of the substrate thus detected, a correction unit 72 which corrects the drawing position of a pattern by using a correction amount obtained from the relative position thus operated, and a drawing unit 150 which draws a pattern at a corrected drawing position on the substrate by using a charged particle beam.

Description

  The present invention relates to a charged particle beam drawing apparatus and a charged particle beam drawing method, for example, to drawing position correction of a drawing apparatus that draws a pattern on a substrate using an electron beam.

  Lithography technology, which is responsible for the progress of miniaturization of semiconductor devices, is an extremely important process for generating a pattern among semiconductor manufacturing processes. In recent years, with the high integration of LSI, circuit line widths required for semiconductor devices have been reduced year by year. In order to form a desired circuit pattern on these semiconductor devices, a highly accurate original pattern (also referred to as a reticle or a mask) is required. Here, the electron beam (electron beam) drawing technique has an essentially excellent resolution, and is used for producing a high-precision original pattern.

  FIG. 12 is a conceptual diagram for explaining the operation of the variable shaped electron beam drawing apparatus. The variable shaped electron beam (EB) drawing apparatus operates as follows. In the first aperture 410, a rectangular opening for forming the electron beam 330, for example, a rectangular opening 411 is formed. Further, the second aperture 420 is formed with a variable shaping opening 421 for shaping the electron beam 330 having passed through the opening 411 of the first aperture 410 into a desired rectangular shape. The electron beam 330 irradiated from the charged particle source 430 and passed through the opening 411 of the first aperture 410 is deflected by the deflector, passes through a part of the variable shaping opening 421 of the second aperture 420, and passes through a predetermined range. The sample 340 mounted on a stage that continuously moves in one direction (for example, the X direction) is irradiated. That is, the drawing area of the sample 340 mounted on the stage in which the rectangular shape that can pass through both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is continuously moved in the X direction. Drawn on. A method of creating an arbitrary shape by passing both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is referred to as a variable shaping method.

  Here, for example, in an electron beam drawing apparatus that draws a pattern on an exposure mask substrate using a square glass substrate, improvement in the conveyance position accuracy for conveying the mask substrate is required as the pattern to be drawn becomes finer. ing. For example, it is necessary to accurately place the mask substrate on the stage in order to improve the drawing accuracy. However, even if the position of the stage is detected, the position of the mask substrate on the stage has not been detected. For this reason, it is difficult to grasp whether or not the mask substrate is placed on the stage with high accuracy.

  Also, when drawing is performed in the drawing apparatus, the outer peripheral portion is covered with a frame-shaped substrate cover so that the insulating portion on the end face of the mask substrate as a sample is not charged by the reflected electrons of the irradiated electron beam. (For example, refer to Patent Document 1). In such a case, it is necessary for the substrate cover to be accurately placed on the mask substrate in order to improve the drawing accuracy. However, conventionally, there has been no means for grasping whether or not the substrate cover is accurately placed on the mask substrate.

JP 2008-058809 A

  As described above, even if the position of the stage is detected, the position of the mask substrate on the stage has not been measured. For this reason, it is difficult to grasp whether or not the mask substrate is placed on the stage with high accuracy. Further, there is no means for grasping whether or not the substrate cover is placed on the mask substrate with high accuracy. Therefore, the drawing is performed with the position shifted, and it is difficult to perform high-precision drawing.

  Therefore, an object of the present invention is to provide a drawing apparatus and method capable of overcoming such problems and irradiating a beam at a high-precision drawing position.

A charged particle beam drawing apparatus according to one embodiment of the present invention includes:
A detection unit for detecting the position of the substrate to be drawn;
A stage on which the substrate is placed;
A calculation unit that calculates the relative position between the substrate and the stage using the detected position of the substrate;
A correction unit that corrects the drawing position of the pattern using the correction amount obtained from the calculated relative position;
A drawing unit that draws a pattern at a corrected drawing position on the substrate using a charged particle beam in a state where the substrate is arranged on the stage;
It is provided with.

  By grasping the relative position between the substrate and the stage, the planned drawing position can be corrected.

The charged particle beam drawing apparatus according to another aspect of the present invention includes:
A detection unit for detecting the position of the substrate to be drawn;
A substrate cover that opens at the center and exposes the center of the substrate surface and covers the outer periphery of the substrate;
An arithmetic unit that calculates the relative position between the substrate and the substrate cover using the detected position of the substrate;
A correction unit that corrects the drawing position of the pattern using the correction amount obtained from the calculated relative position;
A drawing unit that draws a pattern at a corrected drawing position on the substrate using a charged particle beam in a state where the outer periphery of the substrate is covered by the substrate cover;
It is provided with.

  By grasping the relative position between the substrate and the substrate cover, the planned drawing position can be corrected.

The drawing unit has a first chamber for drawing a substrate,
The charged particle beam lithography system
A transport system for transporting the substrate to the first chamber;
A second chamber different from the first chamber, located in the middle of transferring the substrate to the first chamber;
Further comprising
It is preferable that the detection unit detects the position of the substrate in the second chamber.

The apparatus further includes an attachment / detachment device that moves up and down and attaches / detaches the substrate cover to / from the substrate,
Preferably, the detection unit further detects the position of the substrate cover at the same height position at which the position of the substrate is measured by raising and lowering the substrate and the substrate cover by the attachment / detachment device.

The charged particle beam drawing method of one embodiment of the present invention includes:
Detect the position of the substrate to be drawn,
Using the detected position of the substrate, the relative position between the substrate and the stage on which the substrate is placed is calculated,
Using the correction amount obtained from the calculated relative position, correct the pattern drawing position,
A pattern is drawn at a corrected drawing position on the substrate using a charged particle beam in a state where the substrate is arranged on the stage.

  According to the present invention, it is possible to irradiate a beam to a highly accurate drawing position. Therefore, highly accurate drawing can be performed.

1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to Embodiment 1. FIG. FIG. 4 is a flowchart showing main steps of the drawing method according to Embodiment 1. FIG. 3 is a top conceptual diagram illustrating a conveyance path in the drawing apparatus according to the first embodiment. FIG. 3 is a top view showing a substrate cover in the first embodiment. FIG. 5 is a top view showing a state where the substrate cover of FIG. 4 is attached to the substrate. It is sectional drawing of the board | substrate cover of FIG. 6 is a conceptual diagram illustrating a configuration of a substrate cover attaching / detaching mechanism and a height position for position measurement in Embodiment 1. FIG. 6 is a diagram for explaining the operation of the transfer robot according to Embodiment 1. FIG. 6 is a diagram illustrating an example of a relative position between a stage and a substrate in Embodiment 1. FIG. 6 is a diagram illustrating an example of a relative position between a substrate and a substrate cover in Embodiment 1. FIG. FIG. 5 is a conceptual diagram showing another configuration for detecting the position of the substrate and the position of the substrate cover in the first embodiment. It is a conceptual diagram for demonstrating operation | movement of the conventional variable shaping type | mold electron beam drawing apparatus.

  Hereinafter, in the embodiment, a configuration using an electron beam will be described as an example of a charged particle beam. However, the charged particle beam is not limited to an electron beam, and a beam using charged particles such as an ion beam may be used.

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to the first embodiment. In FIG. 1, a drawing apparatus 100 is an example of a charged particle beam drawing apparatus. Here, in particular, an example of a variable shaping type electron beam drawing apparatus is shown. The drawing apparatus 100 includes a drawing unit 150, a control unit 160, a loading / unloading port (I / F) 120, a load lock (L / L) chamber 130, a robot (R) chamber 140, an alignment (ALN) chamber 146, a substrate cover attaching / detaching chamber. 148 (second chamber) and a vacuum pump 170. The drawing apparatus 100 draws a desired pattern on the substrate 101 using the electron beam 200.

  The drawing unit 150 includes an electron column 102 and a drawing chamber 103 (first chamber). In the electron column 102, an electron gun 201, an illumination lens 202, a first aperture 203, a projection lens 204, a deflector 205, a second aperture 206, an objective lens 207, and a deflector 208 are arranged. In the drawing chamber 103, an XY stage 105 is arranged so as to be movable. On the XY stage 105, a plurality of support pins 106 (an example of a support portion) are arranged. The substrate 101 on which the substrate cover 10 is mounted is placed on a plurality of support pins 106. On the XY stage 105, a mirror for laser measurement of the position of the XY stage 105 is disposed. Although not shown, the substrate 101 is grounded (grounded) to the drawing apparatus 100 via the substrate cover 10. In addition, a transfer robot 122 that transfers the substrate 101 is disposed in the carry-in / out opening 120. A transfer robot 142 that transfers the substrate 101 is disposed in the robot chamber 140.

  The vacuum pump 170 exhausts the gas in the robot chamber 140, the alignment chamber 146, and the substrate cover attaching / detaching chamber 148 via the valve 172. Thereby, the robot chamber 140, the alignment chamber 146, and the substrate cover attaching / detaching chamber 148 are maintained in a vacuum atmosphere. The vacuum pump 170 exhausts the gas in the electron column 102 and the drawing chamber 103 via the valve 174. As a result, the inside of the electron column 102 and the drawing chamber 103 are maintained in a vacuum atmosphere. Further, the vacuum pump 170 exhausts the gas in the load lock chamber 130 via the valve 176. Thereby, the inside of the load lock chamber 130 is controlled to a vacuum atmosphere as necessary. In addition, gate valves 132, 134, and 136 are disposed at boundaries between the loading / unloading port 120, the load lock chamber 130, the robot chamber 140, and the drawing chamber 103. Examples of the substrate 101 include an exposure mask substrate that transfers a pattern onto a wafer. The mask substrate includes, for example, mask blanks on which a resist is applied and no pattern is formed yet.

  The control unit 160 includes a control computer 110, a memory 112, a deflection control circuit 114, a plurality of laser length measuring devices 60 and 116, and a storage device 141 such as a magnetic disk. The control computer 110, the memory 112, the deflection control circuit 114, the plurality of laser length measuring devices 60 and 116, and the storage device 141 are connected to each other via a bus (not shown).

  In the control computer 110, a drawing data processing unit 50, a measurement unit 52, a relative position calculation unit 53, a conveyance processing unit 54, a correction amount calculation unit 56, and a drawing processing control unit 58 are arranged. Each function such as the drawing data processing unit 50, the measurement unit 52, the conveyance processing unit 54, the relative position calculation unit 56, and the drawing processing control unit 58 may be configured by software such as a program. Alternatively, it may be configured by hardware such as an electronic circuit. Alternatively, a combination thereof may be used. The input data necessary for the control computer 110 or the calculated result is stored in the memory 112 each time.

  In the deflection control circuit 114, a correction unit 72 and a deflection amount calculation unit 74 are arranged. Each function such as the correction unit 72 and the deflection amount calculation unit 74 may be configured by software such as a program. Alternatively, it may be configured by hardware such as an electronic circuit. Alternatively, a combination thereof may be used. Input data necessary for the deflection control circuit 114 or the calculated result is stored in a memory (not shown) each time.

  The drawing unit 150 is controlled by the drawing processing control unit 58 and drives each device in the drawing unit 150 according to the control content. The carry-in / out port 120, the load lock chamber 130, the alignment chamber 146, the substrate cover attaching / detaching chamber 148, the vacuum pump 170, and the valves 172, 174, 176 are controlled by the transport processing unit 54 controlled by the drawing processing control unit 58. In accordance with the contents of control, the equipment in the carry-in / out port 120, the load lock chamber 130, the alignment chamber 146, and the substrate cover attaching / detaching chamber 148, the vacuum pump 170, and the valves 172, 174, and 176 are driven.

  Here, FIG. 1 shows components necessary for explaining the first embodiment. Needless to say, the drawing apparatus 100 may normally include other necessary configurations. In FIG. 1, one laser length measuring device 116 is described for measuring the position of the XY stage 105. However, in order to measure each of the x and y directions, a plurality of laser length measuring devices 116a, Needless to say, b is arranged. Similarly, one laser length measuring device 60 is described for measuring the position of the substrate 101 and the substrate cover 10. However, in order to measure the x and y directions and the rotation angle θ, a plurality of lasers are used as described later. It goes without saying that the length measuring devices 60a, b, c are arranged. The transport robots 122 and 142 may be any mechanical mechanism such as an elevator mechanism or a rotation mechanism.

  FIG. 2 is a flowchart showing main steps of the drawing method according to the first embodiment. 2, the drawing method according to the first embodiment includes a conveyance processing step (S102), a position measurement step (S104), a determination step (S106), a relative position calculation step (S108), and a correction amount calculation step ( A series of steps such as S110), a shot data generation step (S120), a correction step (S140), and a drawing step (S142) are performed.

  First, the substrate 101 is disposed at the carry-in / out port 120.

  Next, as a transfer processing step (S102), the transfer processing unit 54 transfers the substrate 101 to the drawing chamber 103.

  FIG. 3 is a top conceptual view showing a transport path in the drawing apparatus according to the first embodiment. After the gate valve 132 is opened, the substrate 101 disposed at the carry-in / out opening 120 is carried onto a support member in the L / L chamber 130 by the carrying robot 122. Then, after closing the gate valve 132, the gate valve 134 is opened, and the transfer robot 142 is transferred to the stage in the alignment chamber 146 via the robot chamber 140. Then, the substrate 101 is aligned in the alignment chamber 146. The aligned substrate 101 is transferred by the transfer robot 142 via the robot chamber 140 onto the substrate cover attaching / detaching mechanism in the substrate cover attaching / detaching chamber 148. Then, the substrate 101 on which the substrate cover 10 is mounted in the substrate cover attaching / detaching chamber 148 is then transferred onto the XY stage 105 in the drawing chamber 103 with the gate valve 136 opened. Then, after the gate valve 136 is closed, a predetermined pattern is drawn on the substrate 101 on the XY stage 105.

  On the other hand, when drawing is completed, the gate valve 136 is opened, and the substrate 101 on which the substrate cover 10 is mounted is moved into the robot chamber 140 by the transfer robot 142 from the XY stage 105 of the drawing chamber 103. Then, after the gate valve 136 is closed, it is transferred onto a substrate cover attaching / detaching mechanism in the substrate cover attaching / detaching chamber 148. Then, the substrate cover 10 is removed from the substrate 101 by the substrate cover attaching / detaching mechanism in the substrate cover attaching / detaching chamber 148. The substrate cover 10 removed from the substrate 101 is stored on a substrate cover attaching / detaching mechanism in the substrate cover attaching / detaching chamber 148. The substrate 101 from which the substrate cover 10 has been removed in the substrate cover attaching / detaching chamber 148 opens the gate valve 134, and the substrate 101 is transferred to the stage in the load lock chamber 130 by the transfer robot 142. Then, after closing the gate valve 134, the gate valve 132 is opened, and the substrate 101 is unloaded to the loading / unloading port 120 by the transfer robot 122. During these operations, if the degree of vacuum in each chamber decreases, the vacuum pump 170 is activated each time to maintain the degree of vacuum. Alternatively, the valve 172 or the valve 174 is opened and closed, and is evacuated by the operating vacuum pump 170 to maintain a desired degree of vacuum.

  As described above, the loading / unloading port (I / F) 120, the L / L chamber 130, the robot chamber 140, which are located on the transfer path for transferring the substrate from the loading / unloading port 120 to the drawing chamber 103 (first chamber), The alignment chamber 146, the substrate cover attaching / detaching chamber 148, and the devices disposed in these chambers are examples of the transport system.

  As the position measurement step (S104), the measurement unit 52 detects the position of the substrate 101 being transported. The measurement unit 52 is an example of a detection unit. Similarly, the measurement unit 52 detects the position of the substrate cover 10. The measurement unit 52 detects the position of the substrate 101 in a substrate cover attaching / detaching chamber 148 (second chamber), for example, different from the drawing chamber 103, which is located in the middle of transporting the substrate 101 to the drawing chamber 103. Similarly, the measurement unit 52 detects the position of the substrate cover 10 in the substrate cover attaching / detaching chamber 148.

  The position of the substrate 101 and the position of the substrate cover 10 are measured by a plurality of laser length measuring devices 60. For example, at one corner of the four corners of the rectangular substrate 101, the side surface of the substrate 101 is irradiated with laser, and the reflected light is used by the laser length measuring device 60a to determine the position in the y direction. The long device 60b measures the position in the x direction. Further, the laser length measuring device 60c uses the reflected light to irradiate the side surface of the substrate 101 with another corner portion located at the diagonal corner of the four corners of the rectangular substrate 101, and the x direction Measure the position of. Or you may measure the position of ay direction about a diagonal. By measuring the positions of at least three points, the position of the substrate 101 in the x and y directions and the angle θ in the rotation direction can be detected.

  Similarly, for example, at one corner of the four corners of the square substrate cover 10, the side surface of the substrate cover 10 is irradiated with laser, and the reflected light is used to cause the laser length measuring device 60a to move in the y direction. The position is measured by the laser length measuring device 60b in the x direction. Further, the laser length measuring device 60c uses the reflected light by irradiating the side surface of the substrate cover 10 with a laser beam at the other corner portion located at the diagonal corner of the four corners of the rectangular substrate cover 10. Measure the position in the x direction. Or you may measure the position of ay direction about a diagonal. By measuring the positions of at least three points, the position of the substrate cover 10 in the x and y directions and the angle θ in the rotation direction can be detected.

  Here, the positions of the substrate 101 and the substrate cover 10 in the substrate cover attaching / detaching chamber 148 are detected, but the present invention is not limited to this. The positions of the substrate 101 and the substrate cover 10 in other chambers may be detected. For example, the position may be detected in the drawing chamber 103 or the alignment chamber 146. Alternatively, the position may be detected in the robot chamber 140 after the substrate 101 is aligned in the alignment chamber 146. It is only necessary that the position can be detected after the alignment of the substrate 101 in the alignment chamber 146 and before the drawing in the drawing chamber 103.

FIG. 4 is a top view showing the substrate cover in the first embodiment.
FIG. 5 is a top view showing a state in which the substrate cover of FIG. 4 is attached to the substrate.
6 is a cross-sectional view of the substrate cover of FIG.
The substrate cover 10 includes, for example, three contact support members 12 and a rectangular frame 16 (an example of a frame-shaped member). The contact support member 12 is attached from the upper surface side of the frame 16. The contact support member 12 is attached so as to project inward from the inner peripheral end of the frame 16. Moreover, you may project outside the outer peripheral end. The contact support member 12 is fixed to the frame 16 by, for example, screwing or welding. On the back surface side of each contact support member 12, a pin 18 serving as a contact portion is disposed at a position inside the inner peripheral end of the frame 16 with the front end facing the back surface side.

  The frame 16 is made of a plate material, and has an outer peripheral dimension larger than the outer peripheral end of the substrate 101 and an opening formed in an inner central portion smaller than the outer peripheral end of the substrate 101. That is, as shown in FIG. 5, when the substrate cover 10 is overlaid on the upper portion of the substrate 101 from above, the entire outer periphery of the substrate 101 indicated by the dotted line is formed so as to overlap the frame 16. Thus, the substrate cover 10 covers the entire outer peripheral portion of the substrate 101 from above. As described above, the substrate cover 10 is open at the center to expose the center of the surface of the substrate 101 and to cover the outer periphery of the substrate 101. The three pins 18 bite into the film formed on the substrate 101 and are electrically connected to the conductive film also formed on the substrate 101.

  The substrate cover 10 is preferably formed entirely of a conductive material, or formed entirely of an insulating material and coated on the surface thereof with a conductive material. As the conductive material, a metal material such as copper (Cu) or titanium (Ti) and an alloy thereof is suitable, and as the insulating material, a ceramic material such as alumina is suitable. For example, the frame 16 is preferably made of a material obtained by coating Ti on alumina. Each contact support member 12 is preferably made of conductive zirconia ceramics.

  FIG. 7 is a conceptual diagram showing the configuration of the substrate cover attaching / detaching mechanism and the height position of position measurement in the first embodiment. In FIG. 7, the substrate cover attaching / detaching mechanism 32 includes a plurality of rod-shaped support members 34 mounted on a lift table 36, a plurality of support members 34 that move up and down together with the lift table 36, and a plurality of bar-shaped liftable mechanisms. Substrate support pins 40 are provided. For example, the substrate cover 10 is supported at three points by the three support members 34. Similarly, for example, the substrate 101 is supported at three points by the three substrate support pins 40. Both are not limited to three-point support, and may be supported at four or more points. First, before the substrate 101 is transported, the substrate cover 10 is placed on the plurality of support members 34 of the lifting mechanism 30. Then, as shown in FIG. 7A, the lifting mechanism 30 or the substrate support pin is provided so that at least a gap capable of transporting the substrate 101 can be secured between the back surface of the substrate cover 10 and the upper surface of the substrate support pin 40. 40 is in a state of being moved up and down. For example, the lifting mechanism 30 on which the substrate cover 10 is placed may be moved upward while the substrate support pins 40 are fixed at the substrate placement reference height. In this state, the substrate 101 is transferred from the robot chamber 140 onto the substrate support pins 40 in the substrate cover attaching / detaching chamber 148 by the transfer robot 142.

  Subsequently, as shown in FIG. 7B, the substrate cover 10 is placed on the substrate 101 placed on the substrate support pins 40 by lowering the elevating mechanism 30. Further, a laser is irradiated on the side surface of the substrate 101 placed on the substrate support pin 40 at the substrate placement reference height shown in FIG. 7B, and the position of the substrate 101 is measured by the laser length measuring devices 60a, 60b, 60c. The measured data is output to the measurement unit 52. The measurement unit 52 detects the position of the substrate 101 in the x, y, and θ directions from the position data. Subsequently, as shown in FIG. 7C, the substrate support pins 40 are lowered by the thickness of the substrate 101, and the substrate cover 10 is moved to the substrate mounting reference height. At this height position, the side surface of the substrate cover 10 is irradiated with laser, the position of the substrate cover 10 is measured by the laser length measuring devices 60a, 60b, and 60c, and the measured data is output to the measuring unit 52. The measurement unit 52 detects the position of the substrate cover 10 in the x, y, and θ directions from the position data. As described above, the measurement unit 52 as an example of the detection unit moves the position of the substrate cover 10 at the same height position where the position of the substrate 101 is measured by raising and lowering the substrate 101 and the substrate cover 10 by the substrate cover attaching / detaching mechanism 32. Further detect. With this configuration, the position of the substrate 101 and the position of the substrate cover 10 can be measured with the same laser length measuring device 60a, b, c. Therefore, the number of parts can be reduced. Further, it is possible to eliminate a mechanism for moving the laser length measuring devices 60a, 60b, 60c up and down. Further, by fixing the height positions of the laser length measuring devices 60a, 60b, 60c, it is possible to measure the position with higher accuracy than when both the detection side and the detection side are movable. Needless to say, when the substrate cover 10 is removed from the substrate 101, the elevating mechanism 30 may be raised.

  As a determination step (S106), the transfer processing unit 54 determines whether or not the measured position of the substrate 101 is within a range that can be transferred with respect to a preset transfer reference position. If it is not within the transportable range, the substrate 101 is transported again.

  FIG. 8 is a diagram for explaining the operation of the transfer robot according to the first embodiment. As shown in FIG. 8, the substrate 101 is transported while the back surface of the substrate 101 is supported by the hand of the transport robot 142. Here, when it is not within the transportable range in the determination step (S <b> 106), the transport robot 142 once takes out the substrate 101 from the substrate support pins 40 and re-places it on the substrate support pins 40 again. At that time, the conveyance position may be finely adjusted using the measured position data of the substrate 101. At this time, the substrate 101 may be placed after being taken out from the substrate cover attaching / detaching chamber 148 to the robot chamber 140 side, or may be placed only by moving within the substrate cover attaching / detaching chamber 148. Then, the position of the substrate 101 and the position of the substrate cover 10 are detected again as a position measurement step (S104). In the determination step (S106), the process from the repositioning by the transfer robot 142 to the determination step (S106) is repeated until it falls within the transportable range.

  In the relative position calculation step (S108), the relative position calculation unit 53 calculates the relative positions (Δx11, Δy11, Δθ11) between the substrate 101 and the XY stage 105 using the detected position of the substrate 101. Similarly, the relative position calculation unit 53 calculates the relative positions (Δx21, Δy21, Δθ21) between the substrate 101 and the substrate cover 10 using the detected position of the substrate 101 and the position of the substrate cover 10.

In the correction amount calculation step (S110), the correction amount calculation unit 56 calculates a correction amount for correcting the drawing position using the relative position between the substrate 101 and the XY stage 105. The arrangement reference position of the substrate 101 on the XY stage 105 may be set in advance. Then, by subtracting the relative position (Δx12, Δy12, Δθ12) between the position of the XY stage 105 and the arrangement reference position of the substrate 101 from the relative position (Δx11, Δy11, Δθ11) between the substrate 101 and the XY stage 105, the XY stage. A relative position (Δx13, Δy13, Δθ13) between the arrangement reference position on 105 and the position of the substrate 101 when transported on the XY stage can be obtained. Then, correction amounts (δ1 (x), δ1 (y)) for correcting each position (x, y) in the surface of the substrate 101 can be obtained from the relative position. The correction amounts (δ1 (x), δ1 (y)) are defined by the following equation (1).
(1) (δ1 (x), δ1 (y)) = f1 (Δx13, Δy13, Δθ13)

  In Expression (1), a function f for directly obtaining a correction amount (δ1 (x), δ1 (y)) from a relative position (Δx11, Δy11, Δθ11) between the substrate 101 and the XY stage 105 may be used. . Then, the XY stage 105 may be moved so that the placement reference position on the XY stage 105 comes to the transport position of the substrate 101 before the substrate 101 is transported to the drawing chamber 103. Whether the arrangement reference position on the XY stage 105 has moved to the transport position of the substrate 101 is determined by the measurement unit 52 irradiating the mirror 209 on the XY stage 105 with a laser using the laser length measuring device 116. The position of the XY stage 105 in the x and y directions may be measured and confirmed using the reflected light.

  FIG. 9 is a diagram illustrating an example of a relative position between the stage and the substrate in the first embodiment. FIG. 9 shows an example of the relative positional relationship between the XY stage 105 and the substrate 101 when the substrate 101 is transferred into the drawing chamber 103 while keeping the position of the substrate 101 on the substrate support pin 40 in the substrate cover attaching / detaching chamber 148. ing. The position of the conveyed substrate 101 (solid line) is deviated from the desired arrangement reference position (dotted line). Therefore, at the time of drawing, it is only necessary to correct the drawing position by the calculated correction amount (δ1 (x), δ1 (y)).

  Similarly, the correction amount calculation unit 56 calculates a correction amount for correcting the drawing position using the relative position between the substrate 101 and the substrate cover 10.

FIG. 10 is a diagram illustrating an example of a relative position between the substrate and the substrate cover in the first embodiment. FIG. 10A shows a state where the substrate cover 10 is displaced in the x and y directions with respect to the substrate 101 as an example. FIG. 10B shows a state where the substrate cover 10 is displaced in the rotation angle θ direction with respect to the substrate 101 as another example. Of course, there may be a combination of both. When the position of the substrate cover 10 is shifted, the generated magnetic field fluctuates due to the shift. Therefore, the trajectory shifts due to the influence of the fluctuation of the magnetic field applied to the irradiated electron beam 200. Therefore, the correction amount calculation unit 56 uses the relative positions (Δx21, Δy21, Δθ21) between the substrate 101 and the substrate cover 10 to calculate each position in the surface of the substrate 101 due to the fluctuation of the magnetic field by the following equation (2). A correction amount (δ2 (x), δ2 (y)) for correcting the drawing position shift at (xy) is calculated.
(2) (δ2 (x), δ2 (y)) = f2 (Δx21, Δy21, Δθ21)

  The functions f1 and f2 in the expressions (1) and (2) may be obtained in advance through experiments or the like.

  In the shot data generation step (S120), the drawing data processing unit 50 receives drawing data from the storage device 141, performs a plurality of stages of data conversion processing, and generates apparatus-specific shot data. The drawing data processing unit 50 converts a plurality of figure patterns defined in the drawing data into shot figures of a size that can be irradiated with one electron beam 200 (size that can be formed), and the irradiation amount and irradiation of each shot figure. Shot data in which a position, a shot figure type, a shot figure size, and the like are defined is generated.

  As the correction step (S140), the correction unit 72 inputs shot data, and further, the correction amount (δ1 (x), δ1 (y)) obtained from the relative position between the substrate 101 and the XY stage 105, and the substrate 101 A correction amount (δ2 (x), δ2 (y)) obtained from a relative position with respect to the substrate cover 10 is input. Then, the correction amount (δ1 (x), δ1 (y)) and the correction amount (δ2 (x), δ2 (y)) are added to the coordinate value (x, y) of the irradiation position (drawing position) of each shot figure. By doing so, the drawing position of the pattern is corrected.

  In the drawing step (S142), the deflection amount calculation unit 74 calculates a deflection amount for deflecting the electron beam 200 to the corrected drawing position. Similarly, the electron beam 200 is irradiated for the irradiation amount (irradiation time) defined for each shot figure, and when the irradiation time elapses, a deflection amount for deflecting the electron beam 200 to be shielded is calculated. Similarly, a deflection amount for forming a graphic of the graphic type and size defined for each shot graphic is calculated. Then, the deflection voltage of each deflection amount is applied to the corresponding deflector. By such each deflection, the drawing unit 150 performs correction on the substrate 101 using the electron beam 200 in a state where the substrate 101 in which the outer periphery of the substrate 101 is covered by the substrate cover 10 is disposed on the XY stage 105. A pattern is drawn at the drawn position. Specifically, the following operation is performed.

  An electron beam 200 emitted from an electron gun 201, which is an example of an irradiation unit, is formed into an electron beam for one shot that has an irradiation amount (irradiation time) defined for each shot figure by a blanking mechanism (not shown). Is done. Then, the illumination lens 202 illuminates the entire first aperture 203 having a rectangular hole, for example, a rectangular hole. Here, the electron beam 200 is first formed into a rectangle, for example, a rectangle. Then, the electron beam 200 of the first aperture image that has passed through the first aperture 203 is projected onto the second aperture 206 by the projection lens 204. The position of the first aperture image on the second aperture 206 is deflection-controlled by the deflector 205 and can be changed to the beam shape and size. As a result, the electron beam 200 is shaped into a beam having a graphic type and size defined for each shot graphic. Thus, the electron beam 200 is variably shaped. Then, the electron beam 200 of the second aperture image that has passed through the second aperture 206 is focused by the objective lens 207 and deflected by the deflector 208. As a result, for example, the above-described corrected drawing position of the substrate 101 on the continuously moving XY stage 105 is irradiated.

  Here, in the above-described example, the position of the substrate 101 and the position of the substrate cover 10 are detected using the laser length measuring devices 60a, 60b, 60c, but the detection method is not limited to this.

  FIG. 11 is a conceptual diagram showing another configuration for detecting the position of the substrate and the position of the substrate cover in the first embodiment. As shown in FIG. 11, it is preferable that at least one corner of the four corners of the substrate 101 is picked up by a camera 62 such as a CCD camera from below. In that case, it images so that the image of both the x direction end of a corner | angular part and a y direction end may be obtained. The captured image data is output to the measurement unit 52. The measurement unit 52 can detect the position of the substrate 101 by measuring the positional relationship between the x-direction end and the y-direction end of the corner obtained from the image data. Similarly, it is also preferable that at least one corner of the four corners of the substrate cover 10 is imaged by the camera 62 from below. In that case, it images so that the image of both the x direction end of a corner | angular part and a y direction end may be obtained. The captured image data is output to the measurement unit 52. Then, the measurement unit 52 can detect the position of the substrate cover 10 by measuring the positional relationship between the x-direction end and the y-direction end of the corner obtained from the image data. Here, as an example, the image is taken from below, but the present invention is not limited to this, and the image may be taken from above or from an oblique direction.

  As described above, according to the first embodiment, by grasping the relative position between the substrate 101 and the XY stage 105, the planned drawing position can be corrected by the arrangement error of the substrate 101. Furthermore, by grasping the relative position between the substrate 101 and the substrate cover 10, it is possible to correct the expected drawing position by the amount of positional deviation caused by the magnetic field variation due to the relative positional relationship between the substrate 101 and the substrate cover 10. Therefore, the planned drawing position can be corrected by performing at least one of them.

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used. For example, although the description of the control unit configuration for controlling the drawing apparatus 100 is omitted, it goes without saying that the required control unit configuration is appropriately selected and used.

  In addition, all charged particle beam writing apparatuses, charged particle beam writing methods, and substrate holders that include the elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Substrate cover 12 Contact support member 16 Frame 18 Pin 30 Elevating mechanism 32 Substrate cover attaching / detaching mechanism 34 Support member 36 Elevating stand 40 Substrate support pin 50 Drawing data processing unit 52 Measuring unit 53 Relative position calculating unit 54 Conveying processing unit 56 Correction amount calculation Unit 58 Drawing processing control unit 60, 116 Laser length measuring device 62 Camera 72 Correction unit 74 Deflection amount calculation unit 100 Drawing device 101 Substrate 102 Electron barrel 103 Drawing room 105 XY stage 106 Support pin 110 Control computer 112 Memory 114 Deflection control circuit 120 Loading / unloading port 122, 142 Transport robot 130 Load lock chamber 132, 134, 136 Gate valve 140 Robot chamber 141 Storage device 146 Alignment chamber 148 Substrate cover attaching / detaching chamber 150 Drawing unit 160 Control circuit 170 Vacuum port 172, 174, 176 Valve 200 Electron beam 201 Electron gun 202 Illumination lens 203, 410 First aperture 204 Projection lens 205, 208 Deflector 206, 420 Second aperture 207 Objective lens 209 Mirror 330 Electron beam 340 Sample 411 Opening 421 Variable Shaped Opening 430 Charged Particle Source

Claims (5)

A detection unit for detecting the position of the substrate to be drawn;
A stage on which the substrate is disposed;
A calculation unit that calculates a relative position between the substrate and the stage using the detected position of the substrate;
A correction unit that corrects the drawing position of the pattern using the correction amount obtained from the calculated relative position;
A drawing unit that draws a pattern at a corrected drawing position on the substrate using a charged particle beam in a state where the substrate is disposed on the stage;
A charged particle beam drawing apparatus comprising: A detection unit for detecting the position of the substrate to be drawn;
A substrate cover that opens a central portion to expose a central portion of the substrate surface and covers an outer peripheral portion of the substrate;
A calculation unit that calculates a relative position between the substrate and the substrate cover using a correction amount obtained from the detected position of the substrate;
A correction unit that corrects the drawing position of the pattern using the calculated relative position;
A drawing unit that draws a pattern at a corrected drawing position on the substrate using a charged particle beam in a state where the outer peripheral portion of the substrate is covered by the substrate cover;
A charged particle beam drawing apparatus comprising: The drawing unit has a first chamber for drawing the substrate,
The charged particle beam drawing apparatus comprises:
A transport system for transporting the substrate to the first chamber;
A second chamber different from the first chamber, located in the middle of transferring the substrate to the first chamber;
Further comprising
The charged particle beam drawing apparatus according to claim 1, wherein the detection unit detects a position of the substrate in the second chamber. The apparatus further includes an attachment / detachment device that moves up and down and attaches / detaches the substrate cover to / from the substrate,
The said detection part further detects the position of the said board | substrate cover in the same height position which measures the position of the said board | substrate by raising / lowering the said board | substrate and the said board | substrate cover by the said attachment / detachment apparatus. Charged particle beam lithography system. Detect the position of the substrate to be drawn,
Using the detected position of the substrate, the relative position between the substrate and the stage on which the substrate is placed is calculated,
Using the correction amount obtained from the calculated relative position, correct the pattern drawing position,
A charged particle beam drawing method, wherein a pattern is drawn at a corrected drawing position on the substrate by using a charged particle beam in a state where the substrate is arranged on the stage.

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