Exposure apparatus and method for manufacturing an article

Abstract

This application relates to exposure apparatus and methods for manufacturing articles. According to the invention, the exposure apparatus is used to expose a substrate using exposure light from a light source to transfer a pattern formed on a master plate onto the substrate. The exposure apparatus includes: a substrate stage on which the substrate is mounted; a drive unit configured to drive the substrate stage, the drive unit including a plurality of actuators, each actuator configured to apply a thrust to the substrate stage in a different orientation; and a controller configured to control the drive unit to move the substrate stage in a scanning direction when each of a plurality of projection areas on the substrate is exposed, and to apply a thrust to the substrate stage by each of the plurality of actuators during at least a portion of the time of each movement along the scanning direction.

Description

Technical Field

[0001] This invention relates to exposure equipment and methods for manufacturing articles. Background Technology

[0002] Conventionally, an exposure apparatus is known for exposing a substrate mounted on a substrate stage while moving the substrate stage along the scanning direction.

[0003] In such exposure equipment, productivity needs to be increased by increasing the throughput when exposing substrates.

[0004] Japanese Patent Application Publication No. 2012-142463 discloses an exposure apparatus that reduces exposure time and increases throughput by moving the substrate stage in the scanning direction while changing the substrate stage speed according to a drive distribution curve formed by a sine function during substrate exposure.

[0005] In Japanese Patent Application Publication No. 2012-142463, when a predetermined projection area on a substrate is exposed, the substrate stage is moved in the scanning direction in such a way that the acceleration of the substrate stage in the scanning direction changes from a positive value in a first interval to 0 at a predetermined time, and then from 0 at the predetermined time to a negative value in a second interval.

[0006] On the other hand, an exposure apparatus is known in which a substrate stage is moved in the scanning direction by using a first actuator for applying a first thrust having a positive orientation in the scanning direction to the substrate stage and a second actuator for applying a second thrust having a negative orientation in the scanning direction to the substrate stage.

[0007] Here, when the substrate is exposed in such an exposure apparatus, it is conceivable that a switch from the first actuator to the second actuator will occur when the substrate stage speed is changed and the substrate stage is moved in the scanning direction, as disclosed in Japanese Patent Application Publication No. 2012-142463.

[0008] That is, the acceleration of the substrate stage becomes positive by generating a first thrust only by the first actuator in the first interval, and the acceleration of the substrate stage becomes negative by generating a second thrust only by the second actuator in the second interval.

[0009] At this predetermined moment, when the acceleration of the substrate stage becomes zero, the second thrust is generated simultaneously with the generation of the first thrust.

[0010] That is, when the first thrust and the second thrust become zero at the same time at a predetermined moment, a control deviation occurs relative to the position of the substrate stage, thereby deteriorating the overlap accuracy. Summary of the Invention

[0011] The purpose of this invention is to provide an exposure apparatus that can suppress control deviations relative to the substrate stage position while maintaining increased throughput.

[0012] An exposure apparatus according to the present invention is used to expose a substrate by using exposure light from a light source to transfer a pattern formed on a master plate to the substrate. The exposure apparatus includes: a substrate stage on which the substrate is mounted; a drive unit configured to drive the substrate stage, the drive unit including a plurality of actuators, each actuator configured to apply a thrust to the substrate stage in a different orientation; and a controller configured to control the drive unit to move the substrate stage in a scanning direction when each of a plurality of projection areas on the substrate is exposed, and to apply a thrust to the substrate stage by each of the plurality of actuators during at least a portion of the time of each movement in the scanning direction.

[0013] Other features of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0014] Figure 1A This is a schematic cross-sectional view of an exposure apparatus according to a first embodiment of the present invention.

[0015] Figure 1B This is a top view of the substrate stage in the exposure apparatus according to the first embodiment.

[0016] Figure 2A These are the acceleration distribution curve and velocity distribution curve in the exposure apparatus according to the first embodiment.

[0017] Figure 2B These are the thrust distribution curve and total thrust distribution curve in the exposure apparatus according to the first embodiment.

[0018] Figure 3 This is a flowchart illustrating the exposure process of a substrate in an exposure apparatus according to a first embodiment.

[0019] Figure 4 These are the thrust distribution curve and total thrust distribution curve in the exposure apparatus according to the second embodiment of the present invention.

[0020] Figure 5 These are acceleration and velocity distribution curves from conventional exposure equipment.

[0021] Figure 6A These are acceleration and velocity distribution curves from another conventional exposure device.

[0022] Figure 6B These are the thrust distribution curve and total thrust distribution curve from another conventional exposure device. Detailed Implementation

[0023] The exposure apparatus according to the present invention will now be described in detail with reference to the accompanying drawings. For ease of understanding, the following drawings are drawn to a scale different from the actual scale.

[0024] In the following description, the direction perpendicular to the substrate mounting surface of the substrate stage is defined as the Z direction, and the two directions orthogonal (perpendicular) to each other on the substrate mounting surface are defined as the X direction and the Y direction, respectively.

[0025] Currently, the exposure equipment used in semiconductor device manufacturing mainly uses scanning exposure equipment, which performs exposure while scanning the mask and wafer with an optical system.

[0026] In addition, there is a need to improve productivity, exposure accuracy, and overlap accuracy in exposure equipment.

[0027] To address this need, the acceleration and speed of the mask stage and substrate stage moving in the scanning direction during exposure are increased, thereby shortening exposure time and improving productivity.

[0028] However, due to hardware limitations in increasing acceleration and speed, an exposure apparatus has been proposed that further shortens the exposure time by moving the mask stage and substrate stage in the scanning direction while changing their speeds during exposure.

[0029] On the other hand, in an exposure apparatus that uses a linear motor to move the mask stage and substrate stage in the scanning direction, the heat generated in the coil used in the linear motor increases with the acceleration of the mask stage and substrate stage.

[0030] Therefore, the position measurement accuracy will decrease due to the deformation of the measurement reference caused by thermal expansion in the mask stage and substrate stage, or due to the interference of air density in the optical path of the laser interferometer.

[0031] To address this problem, an exposure apparatus has been proposed that uses low-heat electromagnetic actuators to move the mask stage and substrate stage in the scanning direction.

[0032] In this exposure apparatus, each stage is driven in the scanning direction by using a first electromagnetic actuator for generating a first thrust with a positive orientation in the scanning direction and a second electromagnetic actuator for generating a second thrust with a negative orientation in the scanning direction.

[0033] Here, when exposing a predetermined projection area on the substrate, the consideration is to move the substrate stage in the scanning direction in such a way that the acceleration of the substrate stage changes from a positive value in the first interval to 0 at a predetermined time and then from 0 at the predetermined time to a negative value in the second interval.

[0034] At this point, it is conceivable to adopt the following method: in the first interval, only the first electromagnetic actuator generates the first thrust, while in the second interval, only the second electromagnetic actuator generates the second thrust.

[0035] That is, in this case, the acceleration of the substrate stage can be set to a positive value by generating only the first thrust in the first interval, and the acceleration of the substrate stage can be set to a negative value by generating only the second thrust in the second interval.

[0036] At this time, when the acceleration of the substrate stage changes from a positive value in the first interval to 0 at a predetermined time and then from 0 at a predetermined time to a negative value in the second interval, an instantaneous switch occurs from the first electromagnetic actuator to the second electromagnetic actuator.

[0037] In this case, the instantaneous switching of the actuator used to drive the substrate stage can cause a control deviation in the position of the substrate stage, which will reduce the overlap accuracy.

[0038] Therefore, in the exposure apparatus according to the present invention, by employing the following structure, such control deviation can be suppressed when the substrate stage is driven according to a drive distribution curve having an inflection point (at which point the acceleration (acceleration orientation) of the substrate stage switches from positive to negative).

[0039] [First Embodiment]

[0040] Figure 1A A schematic cross-sectional view of an exposure apparatus 100 according to a first embodiment of the present invention is shown.

[0041] The exposure apparatus 100 according to this embodiment exposes the substrate 104 by using exposure light from a light source to transfer a pattern formed on the mask 102 (original) to the substrate 104.

[0042] Here, the substrate 104 is, for example, a wafer coated with a resist (photoresist), and multiple projection areas, each having the same pattern structure formed by a pre-exposure process, are arranged on the substrate 104.

[0043] The exposure apparatus 100 according to this embodiment employs a step-scan method, wherein each projection area on the substrate 104 is subjected to high-precision exposure while the mask 102 and the substrate 104 are moved synchronously in the scanning direction in the Y direction. In this case, the exposure area is formed into a rectangular or arc-shaped slit.

[0044] like Figure 1A As shown, the exposure apparatus 100 according to this embodiment includes a projection optics system 101, a mask stage 103, a substrate stage 105, an illumination optics system 106, and a controller 111.

[0045] The projection optical system 101 is arranged such that its optical axis AX is parallel to the Z direction, and projects the image of the pattern of the mask 102 onto the image plane of the projection optical system 101, that is, onto the substrate 104.

[0046] For example, the magnification of the projection optical system 101 can be selected from 1 / 4, 1 / 2, and 1 / 5.

[0047] The mask stage 103 is configured to hold the mask 102 and move in the direction of arrow 103a, which is parallel to the Y direction, in the XY plane perpendicular to the optical axis AX of the projection optics system 101 during exposure.

[0048] At this time, the mask stage 103 is driven in a corrective manner to keep the position of the mask stage 103 in the X direction at the target position.

[0049] The position of the mask stage 103 in the X and Y directions is determined by the interferometer 109, which measures the reflected light from the bar mirror 107 set on the mask stage 103.

[0050] The substrate stage 105 is configured to attract and hold the substrate 104 to be mounted by using a chuck (not shown), and to move in the direction of arrow 105a parallel to the Y direction in the XY plane perpendicular to the optical axis AX of the projection optics system 101 during exposure.

[0051] Specifically, the substrate stage 105 includes an XY stage movable in the X and Y directions and a Z stage movable in the Z direction (height direction of substrate 104) parallel to the optical axis AX of the projection optical system 101.

[0052] In addition, the substrate stage 105 includes an adjustment platform that can rotate around the X-axis and Y-axis and a rotary stage that can rotate around the Z-axis.

[0053] Therefore, a six-axis drive system is provided in the substrate stage 105 to match the image of the pattern formed on the mask 102 with the desired projection area on the substrate 104.

[0054] The position of the substrate stage 105 in the X, Y and Z directions is determined by the interferometer 110, which measures the reflected light from the bar mirror 108 disposed on the substrate stage 105.

[0055] The illumination optics system 106 illuminates the mask 102 with light from a light source (not shown) that generates pulsed light (such as an excimer laser).

[0056] Specifically, the illumination optical system 106 includes: a beam shaping optical system for converting the cross-sectional shape (size) of the incident light into a predetermined shape; and an optical integrator for making the light distribution characteristics of the incident light uniform so as to illuminate the mask 102 with uniform illuminance.

[0057] In addition, the illumination optics system 106 includes light-shielding blades, collimating lenses, reflectors, etc., for defining a rectangular illumination area corresponding to the chip size.

[0058] Therefore, the illumination optics system 106 can effectively transmit or reflect pulsed light in the far ultraviolet range.

[0059] The controller 111 includes a CPU, memory, etc., and is configured to provide overall control over each component of the exposure apparatus 100 according to this embodiment.

[0060] Specifically, the controller 111 controls the driving of the mask stage 103 holding the mask 102 and the substrate stage 105 holding the substrate 104 to focus the light from the pattern formed on the mask 102 onto a predetermined projection area of ​​the substrate 104.

[0061] For example, controller 111 adjusts the position of mask stage 103 and substrate stage 105 in the XY plane (position in the X and Y directions and angles around the Z axis) and in the Z direction (various angles around the X and Y axes).

[0062] Furthermore, when exposing a predetermined projection area on the substrate 104, the controller 111 causes the mask stage 103 and the substrate stage 105 to move synchronously in the scanning direction, and causes the substrate stage 105 to move in steps when switching the projection area to be exposed.

[0063] Therefore, the controller 111 can control the exposure process of exposing each projection area of ​​the substrate 104 by scanning the substrate 104 held by the substrate stage 105.

[0064] As the mask stage 103 moves in the direction of arrow 103a, the substrate stage 105 moves in the direction of arrow 105a at a speed corrected by the magnification (reduction magnification) of the projection optics system 101.

[0065] Alignment of the pattern formed on the mask 102 in the XY plane is performed based on the position of the mask stage 103, the position of the substrate stage 105, and the position of each projection area on the substrate 104 relative to the substrate stage 105.

[0066] Here, the positions of the mask stage 103 and the substrate stage 105 are measured by the interferometers 109 and 110 as described above.

[0067] The position of each projection area on the substrate 104 relative to the substrate stage 105 is measured by detecting the position of the mark set on the substrate stage 105 and the position of the alignment mark formed on the substrate 104 using an alignment microscope (not shown).

[0068] Figure 1B A top view is shown of a substrate stage 105 disposed in an exposure apparatus 100 according to this embodiment.

[0069] like Figure 1B As shown, the substrate stage 105 includes a micro stage 201 and a coarse stage 202 that perform short-distance driving and long-distance driving respectively, and the substrate 104 is mounted on them.

[0070] Specifically, the coarse stage 202 is movably supported by the X slider 203 and the Y slider 204, and is connected to the linear motor movable elements 205, 206, 207 and 208.

[0071] The linear motor movable elements 205, 206, 207 and 208 can drive the coarse stage 202 in the X and Y directions respectively by the Lorentz forces generated between them and the linear motor stators 209, 210, 211 and 212.

[0072] The micro stage 201 is connected to the coarse stage 202 in a non-contact manner via multiple electromagnetic actuators 213, 214, 215 and 216 so that it can move in the X and Y directions.

[0073] Electromagnetic actuators 213 and 215 can drive the micro stage 201 in the Y direction, while electromagnetic actuators 214 and 216 can drive the micro stage 201 in the X direction.

[0074] Electromagnetic actuators 213 to 216 can generate only attractive forces and are controlled by controller 111.

[0075] Furthermore, the micro stage 201 is driven by an XYZ linear motor (not shown) in the Z direction, the rotational direction about the X axis, the rotational direction about the Y axis, and the rotational direction about the Z axis to form a six-axis drive system.

[0076] When the micro-stage 201 is driven in the +Y direction, i.e. in the positive orientation of the Y direction, the electromagnetic actuator 213 generates a thrust as an attraction force in the positive orientation of the Y direction.

[0077] On the other hand, when the micro-stage 201 is driven in the -Y direction, i.e. in the negative orientation of the Y direction, the electromagnetic actuator 215 generates a thrust as an attractive force in the negative orientation of the Y direction.

[0078] When the micro-stage 201 is driven in the +X direction, i.e. in the positive orientation of the X direction, the electromagnetic actuator 214 generates a thrust as an attraction force in the positive orientation of the X direction.

[0079] On the other hand, when the micro-stage 201 is driven in the -X direction, i.e., in the negative orientation of the X direction, the electromagnetic actuator 216 generates a thrust as an attractive force in the negative orientation of the X direction.

[0080] That is, in the exposure apparatus 100 according to this embodiment, each of the plurality of actuators applies a thrust with a different orientation to the microstage 201.

[0081] In the exposure apparatus 100 according to this embodiment, the substrate 104 can be positioned at high speed and with high precision by forming the substrate stage 105 as described above.

[0082] Furthermore, in the exposure apparatus 100 according to this embodiment, the driving unit for driving the micro-stage 201 is composed of electromagnetic actuators 213 (first actuator), 214, 215 (second actuator) and 216.

[0083] The number of electromagnetic actuators used to drive the micro stage 201 in the Y direction is not limited to the two mentioned above; three or more electromagnetic actuators can be used to drive the micro stage 201 in the Y direction.

[0084] Figure 5 The acceleration distribution curve Ap and velocity distribution curve Vp of the microstage 201 in the Y direction are shown when a predetermined projection area on a substrate 104 is exposed in a conventional exposure apparatus 400.

[0085] Since the conventional exposure apparatus 400 shown herein has the same construction as the exposure apparatus 100 according to this embodiment, the same components are indicated by the same reference numerals and descriptions are omitted.

[0086] In the following text, the acceleration A and velocity V in the Y direction will be referred to as acceleration A and velocity V, respectively.

[0087] like Figure 5 As shown, when the predetermined projection area on the substrate 104 is exposed in the exposure apparatus 400, the drive of the micro stage 201 is controlled by the controller 111 in the following manner.

[0088] Specifically, firstly, when the micro-motion stage 201 accelerates in the Y direction during the acceleration interval 501 from time t0 to time t3, the acceleration A increases from time t0 to time t1 to reach Amax at time t1.

[0089] Then, after maintaining the acceleration A at Amax between time t1 and time t2, the acceleration A decreases from time t2 to time t3 so that it becomes 0 at time t3, so that the speed V of the micro-motion stage 201 reaches the exposure speed Vs.

[0090] Next, during the constant speed interval 502 from time t3 to time t4, the predetermined projection area on the exposure substrate 104 is scanned while the speed V of the micro-stage 201 in the Y direction is maintained at the exposure speed Vs.

[0091] When the micro-motion stage 201 decelerates in the Y direction during the deceleration interval 503 from time t4 to time t7, the acceleration A decreases from time t4 to time t5 to reach -Amax at time t5.

[0092] Then, the acceleration A is kept at -Amax between time t5 and time t6, and finally the acceleration A increases from time t6 to time t7 so that it becomes 0 at time t7, so that the speed V of the micro-motion stage 201 reaches 0.

[0093] Then, by repeating the above driving and stepping driving in sequence, multiple projection areas set on the entire substrate 104 can be exposed.

[0094] Here, in order to improve productivity, it is conceivable to shorten the time required to process a substrate 104 by increasing the exposure speed Vs and the maximum acceleration Amax to shorten the time periods in each of the acceleration interval 501, exposure interval 502 and deceleration interval 503.

[0095] However, since improvements in maximum acceleration Amax are limited by hardware constraints, improvements in productivity are also limited.

[0096] Figure 6A The acceleration distribution curve Ap and velocity distribution curve Vp of the microstage 201 in the Y direction are shown when a predetermined projection area on a substrate 104 is exposed in another conventional exposure apparatus 500.

[0097] Since the other conventional exposure device 500 shown herein has the same construction as the exposure device 100 according to this embodiment, the same components are indicated by the same reference numerals and descriptions are omitted.

[0098] In the following text, the acceleration A, velocity V, and thrust F in the Y direction will be referred to as acceleration A, velocity V, and thrust F, respectively.

[0099] In the exposure apparatus 500, by periodically changing the acceleration A according to a sine function, the velocity V also changes periodically. Note that... Figure 6A The correlation between acceleration A and velocity V and time is shown for only one cycle.

[0100] Specifically, first, assume that at a predetermined time t0, the acceleration A and velocity V are A0 and -V0, respectively.

[0101] In the variable speed range 601, during the time interval from time t0 to time t1, the acceleration A increases to Amax and then decreases to A0, thereby the velocity V increases from -V0 to V0.

[0102] Next, in the exposure interval 602, during the time interval from time t1 to time t3, the acceleration A decreases to -A0, thereby the velocity V increases from V0 to Vmax and then decreases to V0.

[0103] Then, in the speed change interval 603, during the time interval from time t3 to time t4, the acceleration A decreases to -Amax and then increases to -A0, so that the velocity V decreases from V0 to -V0.

[0104] At this time, in the exposure device 500, the exposure interval 602 is set such that the time t2 when the acceleration A and the velocity V reach 0 and Vmax respectively is set in the middle of the time t1 and the time t3, that is, it is set to (t1+t3) / 2.

[0105] By exposing a predetermined projection area on the substrate 104 within the exposure interval 602, stable exposure can be performed while maintaining the scanning speed of the micro-stage 201 at a substantially constant speed. At this time, the center of the predetermined projection area is exposed at time t2.

[0106] In this way, in the exposure device 500, the time intervals of the speed change interval 601, the exposure interval 602, and the speed change interval 603 can be shortened by performing exposure with varying speeds.

[0107] This reduces the processing time for one substrate 104.

[0108] Figure 6B The thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 in the exposure apparatus 500, and the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 are shown respectively.

[0109] It should be noted that the thrust F1 of the electromagnetic actuator 213 is shown as a positive value to drive the micro stage 201 in the +Y direction, while the thrust F2 of the electromagnetic actuator 215 is shown as a negative value to drive the micro stage 201 in the -Y direction.

[0110] like Figure 6B As shown, the total thrust distribution curve Fp (correlation between total thrust F and time) of electromagnetic actuators 213 and 215 is output based on the acceleration distribution curve Ap (correlation between acceleration A and time) of micro-stage 201.

[0111] That is, the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 changes with the acceleration distribution curve Ap with the same period and phase, so that when the acceleration A of the micro stage 201 becomes ±Amax, the total thrust F becomes ±Fmax.

[0112] The thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 are allocated from the total thrust distribution curve Fp, such that their sum forms the total thrust distribution curve Fp of electromagnetic actuators 213 and 215.

[0113] At this point, the conventional method for allocating the total thrust distribution curve Fp to the individual thrust distribution curves F1p and F2p is to allocate it based on the sign of the total thrust F.

[0114] That is, such as Figure 6B As shown, in the interval before time t2 when the total thrust F is positive and drives the micro-motion stage 201 in the +Y direction, the electromagnetic actuator 213 generates a thrust F1 as an attraction force.

[0115] On the other hand, during the interval after time t2 when the total thrust F is negative and drives the micro-stage 201 in the -Y direction, the electromagnetic actuator 215 generates a thrust F2 as an attraction force.

[0116] In this way, electromagnetic actuators 213 and 215 are controlled such that only one of electromagnetic actuators 213 and 215 generates thrust according to the sign of the acceleration A of the micro stage 201.

[0117] Therefore, as Figure 6B As shown, in the exposure interval 602, after the thrust F1 of the electromagnetic actuator 213, which is F0 at time t1, begins to decrease, it reaches 0 at time t2 and then remains 0 after time t2.

[0118] On the other hand, in the exposure interval 602, the thrust F2 of the electromagnetic actuator 215, which is 0 at time t1, decreases from time t2 and then reaches -F0 at time t3.

[0119] like Figure 6B As shown, since the sum of the thrust distribution curves F1p and F2p forms the total thrust distribution curve Fp, the thrust F1 of the electromagnetic actuator 213 changes abruptly at time t2.

[0120] In other words, the thrust distribution curve F1p (the correlation between thrust F1 and time) of the electromagnetic actuator 213 has a discontinuity relative to the derivative at time t2.

[0121] Similarly, the thrust F2 of the electromagnetic actuator 215 changes abruptly at time t2. In other words, the thrust distribution curve F2p (the correlation between thrust F2 and time) of the electromagnetic actuator 215 also exhibits discontinuity relative to the derivative at time t2.

[0122] In other words, in the exposure device 500, the thrust distribution curves F1p and F2p in the exposure interval 602 are generated as functions that are not differentiable with respect to time at time t2 when the thrusts F1 and F2 become 0 respectively.

[0123] That is, when the acceleration A changes continuously like the acceleration distribution curve Ap of the micro-stage 201 in the exposure device 500, there is an inflection point t2 in the exposure interval 602 where the acceleration A changes from positive to negative instantaneously.

[0124] At the inflection point t2, the thrust F1 of the electromagnetic actuator 213 reaches 0 with a discontinuity relative to the derivative, while the thrust F2 of the electromagnetic actuator 215 also changes from 0 with a discontinuity relative to the derivative.

[0125] Therefore, since the thrust applied to the micro stage 201 at the inflection point t2 is switched instantaneously from electromagnetic actuator 213 to electromagnetic actuator 215, a control deviation may occur in the micro stage 201.

[0126] That is, in the exposure equipment 500, in the exposure interval 602 where the exposure is performed, a control deviation occurs in the micro-stage 201, thereby degrading the overlap accuracy.

[0127] Therefore, in the exposure apparatus 100 according to this embodiment, such control deviation in the micro-stage 201 can be suppressed by performing the following control.

[0128] Figure 2A The acceleration distribution curve Ap and velocity distribution curve Vp of the microstage 201 in the Y direction are shown when a predetermined projection area on a substrate 104 is exposed in the exposure apparatus 100 according to this embodiment.

[0129] In the following text, the acceleration A, velocity V, and thrust F in the Y direction will be referred to as acceleration A, velocity V, and thrust F, respectively.

[0130] In the exposure apparatus 100 according to this embodiment, by setting the acceleration A of the micro-stage 201 to change periodically according to a sine function, the velocity V of the micro-stage 201 also changes periodically. It should be noted that... Figure 2A The correlation between acceleration A and velocity V and time is shown for only one cycle.

[0131] Specifically, first, assume that at a predetermined time t0, the acceleration A and velocity V are A0 and -V0, respectively.

[0132] During the acceleration interval 301 from time t0 to time t1, the acceleration A increases to Amax at time t' and then decreases to A0 at time t1, thus the velocity V increases from -V0 to V0.

[0133] Next, during the exposure interval 302 from time t1 to time t3, the acceleration A decreases to 0 at time t2 and then further decreases to -A0 at time t3, thereby causing the velocity V to increase from V0 to Vmax and then decrease to V0.

[0134] Then, in the acceleration interval 303 from time t3 to time t4, the acceleration A decreases to -Amax at time t” and then increases to -A0 at time t4, so that the velocity V decreases from V0 to -V0.

[0135] At this time, in the exposure apparatus 100 according to this embodiment, the exposure interval 302 is set such that the time t2 when the acceleration A and the velocity V reach 0 and Vmax respectively is set in the middle of time t1 and time t3, that is, set to (t1+t3) / 2.

[0136] In the exposure apparatus 100 according to this embodiment, by exposing a predetermined projection area on the substrate 104 in the exposure interval 302, stable exposure can be performed while maintaining the scanning speed of the micro-stage 201 at a substantially constant speed. At this time, the center of the predetermined projection area is exposed at time t2.

[0137] In this way, in the exposure apparatus 100 according to this embodiment, the time periods of the speed change interval 301, the exposure interval 302, and the speed change interval 303 can be shortened by performing exposure with a change in speed.

[0138] This reduces the processing time for one substrate 104.

[0139] like Figure 2A As shown, in the exposure apparatus 100 according to this embodiment, the acceleration distribution curve Ap in the exposure interval 302 is generated from a differentiable function relative to time.

[0140] In other words, in the exposure apparatus 100 according to this embodiment, the acceleration distribution curve Ap in the exposure interval 302 is generated from a function A(t) that depends on time t, wherein the value of dA(t) / dt exists at any time in the exposure interval 302.

[0141] Figure 2B The thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 and the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 in the exposure apparatus 100 according to this embodiment are shown respectively.

[0142] like Figure 2B As shown, the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 is generated based on the acceleration distribution curve Ap of the micro-stage 201.

[0143] That is, the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 changes with the acceleration distribution curve Ap with the same period and phase, so that when the acceleration A of the micro stage 201 becomes ±Amax, the total thrust F becomes ±Fmax.

[0144] The thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 are allocated from the total thrust distribution curve Fp, such that their sum forms the total thrust distribution curve Fp of electromagnetic actuators 213 and 215.

[0145] In other words, the thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 are generated based on the acceleration command values ​​generated from the acceleration distribution curve Ap of the micro stage 201.

[0146] At this time, the exposure device 100 according to this embodiment performs the allocation of the total thrust distribution curve Fp to the thrust distribution curves F1p and F2p, so that the thrusts F1 and F2 of the electromagnetic actuators 213 and 215 do not become 0 at the same time in the exposure interval 302.

[0147] Specifically, for example, the thrust F1 (first thrust) of the electromagnetic actuator 213 (first actuator) at time t' is Fmax becomes F0 at time t1 when the exposure interval 302 begins, and then monotonically decreases so as to reach 0 at time t3.

[0148] On the other hand, the thrust F2 (second thrust) of the electromagnetic actuator 215 (second actuator), which is 0, decreases from time t1, becomes -F0 at time t3 when the exposure interval 302 is completed, and then decreases monotonically to reach -Fmax at time t”.

[0149] In this way, the thrust applied to the micro stage 201 can be controlled so that the actuator that applies the thrust to the micro stage 201 will not switch instantaneously from electromagnetic actuator 213 to electromagnetic actuator 215 at time t2.

[0150] That is, in the exposure apparatus 100 according to this embodiment, when one of the thrusts of the electromagnetic actuators 213 and 215 reaches 0 or changes from 0 in the exposure interval 302, the other thrust is generated.

[0151] In other words, in the exposure apparatus 100 according to this embodiment, the thrusts F1 and F2 of the electromagnetic actuators 213 and 215 are not both zero in at least a portion of the exposure interval 302.

[0152] In other words, in the exposure apparatus 100 according to this embodiment, the total thrust of the electromagnetic actuators 213 and 215 is applied to the microstage 201 in at least a portion of the exposure zone 302.

[0153] That is, when each of the projection areas on the substrate 104 is exposed, the acceleration distribution curve Ap is generated in such a way that the acceleration A in the Y direction of the micro-stage 201 changes from a positive value in a range to 0 at a predetermined time, and then changes from 0 at the predetermined time to a negative value in a range.

[0154] Similarly, when each of the remaining projection areas on the substrate 104 is exposed, the acceleration distribution curve Ap is generated in such a way that the acceleration A in the Y direction of the micro-stage 201 changes from a negative value in a range to 0 at a predetermined time, and then from 0 at the predetermined time to a positive value in a range.

[0155] In the exposure apparatus 100 according to this embodiment, the controller 111 controls the drive unit to move the micro stage 201 in the scanning direction according to the generated acceleration distribution curve Ap.

[0156] At this time, in the exposure apparatus 100 according to this embodiment, the driving unit is controlled such that when the plurality of projection areas on the substrate 104 are exposed, each of the plurality of actuators applies a thrust to the microstage 201 during at least a portion of the time during each movement along the scanning direction.

[0157] In particular, the drive unit is controlled such that each of the plurality of actuators applies a thrust to the microstage 201 at a predetermined moment when the acceleration A becomes 0 during each movement along the scanning direction when the plurality of projection areas on the substrate 104 are exposed.

[0158] Therefore, in the exposure apparatus 100 according to this embodiment, the occurrence of control deviation in the micro-stage 201 during the exposure interval 302 in which exposure is performed can be suppressed, and the degradation of overlap accuracy can be suppressed.

[0159] In the exposure apparatus 100 according to this embodiment, such as Figure 2B As shown, preferably, when the thrust F1 of the electromagnetic actuator 213 reaches 0 at time t3, the thrust F1 of the electromagnetic actuator 213 changes continuously with respect to the derivative.

[0160] Similarly, preferably, the thrust F2 of the electromagnetic actuator 215 changes continuously from 0 with respect to the derivative at time t1.

[0161] In other words, each of the thrust distribution curves F1p and F2p in the exposure interval 302 is preferably generated from a differentiable function relative to time.

[0162] This can further suppress the occurrence of control deviations in the micro-stage 201 during the exposure interval 302, and further suppress the degradation of overlap accuracy.

[0163] Furthermore, specifically, for example, the thrust distribution curves F1p and F2p of the electromagnetic actuators 213 and 215 in the exposure interval 302 can be expressed as the following equations (1) and (2).

[0164]

[0165]

[0166] Figure 3 This is a flowchart illustrating the exposure process of the substrate 104 in the exposure apparatus 100 according to this embodiment.

[0167] like Figure 3 As shown, when the exposure process of substrate 104 begins (step S1), substrate 104 is transferred to substrate stage 105 (step S2).

[0168] Next, the controller 111 performs the alignment of the substrate 104 (step S3) and calculates the drive distribution curves of the substrate stage 105 and the mask stage 103 based on the layout information of the projection area exposed on the substrate 104 (step S4).

[0169] Then, based on the drive distribution curves of the substrate stage 105 and the mask stage 103 calculated in step S4, the thrust command value of the electromagnetic actuators set in each stage is calculated (step S5), and their output timing is set (step S6).

[0170] Subsequently, the substrate stage 105 and mask stage 103 are driven based on the thrust command value and output timing of the electromagnetic actuator calculated in steps S5 and S6. Each projection area on the substrate 104 is exposed by repeated scanning and stepping (step S7).

[0171] When the exposure of all projection areas on the substrate 104 is completed, the substrate 104 is retrieved from the substrate stage 105 (step S8), and the exposure process of the substrate 104 is completed (step S9).

[0172] As described above, in the exposure apparatus 100 according to this embodiment, the driving unit is controlled such that each of the plurality of actuators applies a thrust to the microstage 201 during at least a portion of the time during each movement along the scanning direction when exposing a plurality of projection areas on the substrate 104.

[0173] Therefore, when the signs of the total thrust F reverse at time t2 in the exposure interval 302, the electromagnetic actuators 213 and 215 will not switch from one to the other.

[0174] Therefore, the occurrence of control deviation in the micro stage 201 during the exposure interval 302 of the exposure can be suppressed, and the degradation of overlap accuracy can be suppressed.

[0175] In the exposure apparatus 100 according to this embodiment, the thrust distribution curves F1p and F2p of the electromagnetic actuators 213 and 215 in the exposure interval 302 are generated by the functions shown in equations (1) and (2). However, the thrust distribution curves F1p and F2p are not limited to these, as long as the above conditions are met.

[0176] Furthermore, the above control method can be similarly applied to driving the micro stage 201 or the mask stage 103 in the X direction via electromagnetic actuators 214 and 216.

[0177] [Second Embodiment]

[0178] Figure 4 The thrust distribution curves F1p and F2p of electromagnetic actuators 213 and 215 and the total thrust distribution curve Fp of electromagnetic actuators 213 and 215 in the exposure apparatus according to the second embodiment of the present invention are shown respectively.

[0179] Since the exposure apparatus shown herein according to this embodiment has the same construction as the exposure apparatus 100 according to the first embodiment, the same components are indicated by the same reference numerals and descriptions are omitted.

[0180] Furthermore, since the acceleration distribution curve Ap and velocity distribution curve Vp of the micro-stage 201 in the Y direction when exposing a predetermined projection area on the substrate 104 in the exposure apparatus according to this embodiment are the same as those in the exposure apparatus 100 according to the first embodiment, their description is omitted.

[0181] Furthermore, since the total thrust distribution curve Fp of the electromagnetic actuators 213 and 215 in the exposure apparatus according to this embodiment is the same as that in the exposure apparatus 100 according to the first embodiment, the description is omitted.

[0182] like Figure 4 As shown, in the exposure apparatus according to this embodiment, similar to the exposure apparatus 100 according to the first embodiment, when one of the thrusts of the electromagnetic actuators 213 and 215 reaches 0 or changes from 0 in the exposure interval 302, the other of the thrusts of the electromagnetic actuators 213 and 215 is generated.

[0183] In other words, in the exposure apparatus according to this embodiment, the thrusts F1 and F2 of the electromagnetic actuators 213 and 215 are not both zero in at least a portion of the exposure interval 302.

[0184] In other words, in the exposure apparatus according to this embodiment, the total thrust of the electromagnetic actuators 213 and 215 is applied to the microstage 201 in at least a portion of the exposure zone 302.

[0185] However, in the exposure apparatus according to this embodiment, unlike the exposure apparatus 100 according to the first embodiment, the thrust F1 of the electromagnetic actuator 213 reaches 0 at a time after the exposure interval 302.

[0186] On the other hand, the thrust F2 of the electromagnetic actuator 215 begins to decrease from the moment before the exposure interval 302.

[0187] Specifically, the thrust F1 of the electromagnetic actuator 213 at time t' is Fmax becomes F0 at time t1 at the beginning of the exposure interval 302, and then decreases monotonically so that it reaches 0 at time t+ after the exposure interval 302.

[0188] On the other hand, the thrust F2 of the electromagnetic actuator 215, which is 0, decreases from time t- before the exposure interval 302, becomes -F0' at time t1 when the exposure interval 302 begins, and then decreases monotonically to reach -Fmax at time t”.

[0189] As described above, in the exposure apparatus according to this embodiment, the moment when each of the thrusts F1 and F2 of the electromagnetic actuators 213 and 215 reaches 0 or changes from 0 is set in the speed change range 301 or 303 instead of the exposure range 302.

[0190] In other words, in the exposure apparatus according to this embodiment, the drive unit is controlled such that each of the plurality of actuators applies a thrust to the microstage 201 at any moment during each movement along the scanning direction when exposing a plurality of projection areas on the substrate 104.

[0191] In this way, control deviations in the microstage 201 that may occur when each of the electromagnetic actuators 213 and 215 is turned on or off, causing the thrust to reach 0 or change from 0 in the exposure interval 302, can also be suppressed.

[0192] In addition, in such Figure 4 In the exposure apparatus according to this embodiment, it is preferable that the thrust F1 of the electromagnetic actuator 213 changes continuously with respect to its derivative when it reaches 0 at time t+. In other words, the thrust F1 of the electromagnetic actuator 213 is preferably generated by a differentiable function with respect to time t at time t+.

[0193] Similarly, preferably, the thrust F2 of the electromagnetic actuator 215 changes continuously from 0 with respect to the derivative at time t. In other words, the thrust F2 of the electromagnetic actuator 215 is preferably generated by a differentiable function with respect to time t at time t.

[0194] As described above, in the exposure apparatus according to this embodiment, the drive unit is controlled such that each of the plurality of actuators applies a thrust to the microstage 201 at any moment during each movement along the scanning direction when exposing a plurality of projection areas on the substrate 104.

[0195] This can further suppress the occurrence of control deviations in the micro-stage 201 within the exposure range 302 during exposure, and can further suppress the degradation of overlap accuracy.

[0196] According to the present invention, an exposure apparatus can be provided that can suppress the occurrence of control deviations relative to the substrate stage position while maintaining increased throughput.

[0197] [Methods for manufacturing articles]

[0198] The method of manufacturing articles using the exposure apparatus according to the invention is applicable to the manufacture of devices, such as semiconductor elements, magnetic storage media, and liquid crystal display elements.

[0199] The method for manufacturing an article according to the present invention includes the steps of exposing a substrate coated with photoresist by using an exposure apparatus according to the present invention, and developing the exposed substrate.

[0200] Furthermore, the method of manufacturing an article according to the present invention includes other known steps for processing the developed substrate (oxidation, coating, deposition, doping, planarization, etching, resist removal, dicing, bonding, encapsulation, etc.).

[0201] Compared with conventional methods, the method of manufacturing articles according to the present invention is advantageous in at least one aspect of the performance, quality, productivity and production cost of the articles.

[0202] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims should be given the broadest interpretation so as to cover all variations and equivalent structures and functions.

Claims

1. An exposure apparatus for exposing a substrate to light from a light source to transfer a pattern formed on a master plate onto the substrate, the exposure apparatus comprising: Substrate stage, the substrate is mounted on the substrate stage; The driving unit is configured to drive the substrate stage along the scanning direction. The driving unit includes a first actuator and a second actuator, which are respectively configured to apply a first thrust and a second thrust to the substrate stage. as well as The controller is configured to control the drive unit so as to expose each of the multiple projection areas on the substrate while moving the substrate stage along the scanning direction during the exposure time period of each exposure in each of the multiple projection areas on the substrate. The controller is configured to cause the first actuator to apply a first thrust to the substrate stage along a first orientation in the scanning direction and to cause the second actuator to apply a second thrust to the substrate stage along a second orientation in the scanning direction opposite to the first orientation. The controller also controls the drive unit to change the total thrust of the first and second thrusts according to a sine function by changing each of the first and second thrusts. When the orientation of the total thrust changes, either the magnitude of the first thrust or the magnitude of the second thrust remains zero, so as to move the substrate stage along the scanning direction during the exposure time period.

2. The exposure apparatus according to claim 1, wherein, The controller controls the drive unit to move the substrate stage in the scanning direction according to the acceleration distribution curve, which is generated by changing the acceleration in the scanning direction from a positive value in a range to 0 at a predetermined time during each exposure of a portion of the projection area on the substrate, and then from 0 at the predetermined time to a negative value in a range.

3. The exposure apparatus according to claim 2, wherein, The controller controls the drive unit to move the substrate stage in the scanning direction according to the acceleration distribution curve, which is generated by changing the acceleration in the scanning direction from a negative value in a range to 0 at a predetermined time during each exposure of the remaining projection area on the substrate, and then from 0 at the predetermined time to a positive value in a range.

4. The exposure apparatus according to claim 2, wherein, The controller generates an acceleration distribution curve for each exposure in the plurality of projection regions based on a differentiable function relative to time.

5. The exposure apparatus according to claim 2, wherein, The controller generates the distribution curves of the first thrust and the second thrust based on the acceleration command values ​​generated from the acceleration distribution curves at each exposure in the plurality of projection regions.

6. The exposure apparatus according to claim 5, wherein, The controller generates distribution curves for the first thrust and the second thrust for each exposure in the plurality of projection regions based on a differentiable function relative to time.

7. The exposure apparatus according to claim 2, wherein, The controller controls the drive unit so that the first actuator and the second actuator apply a first thrust and a second thrust to the substrate stage at the predetermined time, respectively.

8. The exposure apparatus according to claim 1, wherein, The controller controls the drive unit to apply a first thrust and a second thrust to the substrate stage at any time during the exposure period.

9. The exposure apparatus according to claim 1, in, During the first time period included in the exposure time period, a total thrust is applied to the substrate stage along the first orientation; and during the second time period included in the exposure time period, a total thrust is applied to the substrate stage along the second orientation; and During the time interval between the first and second time intervals, the total thrust becomes zero.

10. The exposure apparatus according to claim 1, wherein, Each of the first and second actuators is an electromagnetic actuator.

11. A method for manufacturing an article of articles, comprising: The substrate is exposed using the exposure apparatus according to any one of claims 1 to 10; The exposed substrate is then developed. as well as The developed substrate is processed to manufacture products.

12. A method for transferring a pattern formed on a master plate onto a substrate by exposing a substrate in an exposure apparatus using exposure light from a light source, the exposure apparatus comprising: Substrate stage, the substrate is mounted on the substrate stage; And a driving unit configured to drive a substrate stage along a scanning direction, the driving unit including a first actuator and a second actuator, the first actuator and the second actuator being respectively configured to apply a first thrust and a second thrust to the substrate stage, the method including: The control drive unit is configured to expose each of the multiple projection areas on the substrate while moving the substrate stage along the scanning direction during the exposure time period of each exposure in each of the multiple projection areas on the substrate. The control includes: a control drive unit that causes the first actuator to apply a first thrust to the substrate stage along a first orientation in the scanning direction and causes the second actuator to apply a second thrust to the substrate stage along a second orientation in the scanning direction opposite to the first orientation; and a control drive unit that causes the total thrust of the first and second thrusts to vary according to a sine function by changing each of the first and second thrusts, such that when the orientation of the total thrust changes, either the magnitude of the first thrust or the magnitude of the second thrust remains constant at zero, so as to move the substrate stage along the scanning direction during the exposure time period.

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