Mark detection device, lithography apparatus, production method of article

Abstract

To provide a technique advantageous for accurately detecting a position of an alignment mark disposed on a substrate on various imaging conditions.SOLUTION: A mark detection device for detecting a position of an alignment mark disposed on a substrate includes: a substrate stage for holding and transferring the substrate; an imaging part including a light source for illuminating the alignment mark, and an image sensor for imaging the alignment mark; an imaging control part for controlling the imaging part while synchronizing the substrate stage. An imaging condition of the alignment mark by the imaging part can be changed, and the imaging control part gives a command for imaging to the imaging part at the timing according to the imaging condition.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a mark detection apparatus, a lithography apparatus, and an article manufacturing method. [Background technology]

[0002] Patent Document 1 describes an exposure apparatus that transfers a pattern from an original onto a substrate, in which an alignment mark on the substrate is imaged and its position is detected while a stage that holds the substrate is moved. This exposure apparatus has an optical amplifier with a gate function in its alignment detection system, and captures an instantaneous image of the alignment mark by sending a gate signal to the optical amplifier when the alignment mark is within the detection area. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-233106 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a delay of, for example, 10 to 100 microseconds between the start of driving the light source illuminating the alignment mark and the time when the light emission luminance reaches a peak value or a target value, and this delay time can depend on the light emission luminance. Therefore, changing the light emission luminance can cause a mismatch between the imaging timing of the image sensor capturing the alignment mark and the light emission timing of the light source. Even in a configuration in which an imaging command is issued to the image sensor when the substrate stage holding the substrate reaches a predetermined position, there is a delay between the time when the substrate stage reaches the predetermined position and the time when the image sensor starts capturing images. Therefore, it is necessary to adjust the timing for capturing the alignment mark depending on various imaging conditions, such as the light emission timing of the light source, the speed and acceleration of the substrate stage, and the imaging period (accumulation time) of the image sensor. In addition to the examples given here, the imaging conditions can include various conditions that affect the imaging of the alignment mark.

[0005] An object of the present invention is to provide an advantageous technique for detecting the position of an alignment mark provided on a substrate with high accuracy under various imaging conditions. [Means for solving the problem]

[0006] One aspect of the present invention relates to a mark detection device that detects the position of an alignment mark provided on a substrate, the mark detection device comprising: a substrate stage that holds and moves the substrate; an imaging unit that includes a light source for illuminating the alignment mark and an image sensor that images the alignment mark; and an imaging control unit that controls the imaging unit in synchronization with the substrate stage, wherein the imaging conditions of the alignment mark by the imaging unit are changeable, and the imaging control unit issues an image capture command to the imaging unit at a timing according to the imaging conditions. [Effects of the Invention]

[0007] According to the present invention, an advantageous technique is provided for detecting the position of an alignment mark provided on a substrate with high accuracy under various imaging conditions. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram schematically illustrating the configuration of an exposure apparatus as an example of a lithography apparatus according to the present disclosure. [Figure 2] FIG. 2 is a diagram schematically showing an example of the configuration of an alignment system of the exposure apparatus shown in FIG. [Figure 3] FIG. 4 is a timing chart showing typical signals in the alignment system of the exposure apparatus. [Figure 4] FIG. 10 is a timing chart illustrating a method for determining a delay time. [Figure 5] FIG. 2 is a diagram schematically showing another example of the configuration of the alignment system of the exposure apparatus shown in FIG. [Figure 6] FIG. 2 is a diagram showing an example of the configuration of an imaging control unit. [Figure 7] FIG. 2 is a diagram illustrating the function of a decision circuit. [Figure 8] FIG. 4 is a diagram illustrating an example of the operation of an imaging control unit. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] 1 shows a schematic configuration of an exposure apparatus 100 as an example of a lithography apparatus according to the present disclosure. The exposure apparatus 100 is configured to transfer a pattern of a reticle 112 onto a substrate 114. In the following, an example in which the exposure apparatus 100 is configured as a scanning exposure apparatus will be described, but the exposure apparatus 100 may also be configured as a stepper.

[0011] The exposure apparatus 100 has a function of detecting the positions of alignment marks provided on the substrate 114 while moving the substrate 114. The lithography apparatus of the present disclosure may be an imprint apparatus having a function of detecting the positions of alignment marks provided on the substrate 114 while moving the substrate 114. Such an imprint apparatus can, for example, measure alignment marks provided in all or part of multiple shot areas on the substrate while moving the substrate, and then perform imprint processing on the multiple shot areas.

[0012] The exposure apparatus 100 configured as a scanning exposure apparatus has a projection optical system 120 that projects the pattern of the original 112 onto the substrate 114, and forms a latent image (transfer image) corresponding to the pattern of the original 112 in a photoresist film on the substrate 114 by scanning exposure. The latent image can be converted into a resist pattern, which is a physical pattern, by a development process.

[0013] The exposure apparatus 100 may include an adjustment mechanism 150 that adjusts the optical characteristics of the projection optical system 120 so that the shape of the latent image formed on the substrate 114 is corrected. The adjustment mechanism 150 may include, for example, a drive mechanism 110 that drives the optical element 125 of the projection optical system 120. The adjustment mechanism 150 may also include a substrate drive mechanism 109 that drives the substrate stage 115, and a reticle drive mechanism 108 that drives the reticle stage 113. The exposure apparatus 100 may further include a main controller 103 that controls the scanning of the substrate 114 and the reticle 112 based on a tolerance for a correction residual in the correction of the shape of the latent image formed on the substrate 114, and that controls the adjustment mechanism 150. The exposure apparatus 100 may further include a user interface 104. A user such as an operator can input various information by operating the user interface 104.

[0014] The configuration of the exposure apparatus 100 will be described in more detail below. In FIG. 1, an XYZ coordinate system is defined, with the Z axis parallel to the optical axis of the projection optical system 120 and extending from the substrate 114 to the original 112, and the X and Y axes perpendicular to the Z axis. The exposure light source 101 emits exposure light. The exposure light source 101 can be controlled by a light source control device 102, which is controlled by a main control device 103. The exposure light emitted from the exposure light source 101 can be shaped into a predetermined beam shape by a shaping optical system (not shown) of the illumination optical system 122. The shaped beam enters an optical integrator (not shown), which can form multiple secondary light sources to illuminate the original 112 with a uniform illuminance distribution.

[0015] The illumination optical system 122 may have an aperture stop 126 that determines the numerical aperture (NA) of the illumination optical system 122. The aperture stop 126 may have a substantially circular opening. The illumination system control device 105 may control the diameter of the opening, thereby controlling the numerical aperture (NA) of the illumination optical system 122. The ratio of the numerical aperture of the illumination optical system 122 to the numerical aperture of the projection optical system 120 is called a coherence factor (σ value). The illumination system control device 105 may adjust the σ value by controlling the aperture stop 126 of the illumination optical system 122.

[0016] A half mirror 121 is disposed on the optical path of the illumination optical system 122, and a portion of the exposure light illuminating the original 112 can be reflected and extracted by this half mirror 121. A photosensor 123 is disposed on the optical path of the light reflected by the half mirror 121, and the photosensor 123 detects the intensity of the exposure light (exposure energy).

[0017] The original 112 is held by an original stage 113, and the original stage 113 is driven in the Y-axis direction by an original driving mechanism 108, thereby driving the original 112 in the Y-axis direction. A pattern of a device (article) to be manufactured is formed on the original 112. An illumination optical system 122 illuminates the pattern on the original 112 with exposure light. A projection optical system 120 reduces an image of the pattern on the original 112 by a reduction ratio β and projects it onto the substrate 114. This exposes the photoresist on the substrate 114, and a latent image of the pattern of the original 112 is formed in the photoresist.

[0018] An aperture stop 124 defining a substantially circular opening may be arranged at the pupil plane of the projection optical system 120 (a Fourier transform plane relative to the plane (object plane) on which the original 112 is arranged). The diameter of the opening of the aperture stop 124 may be controlled by a drive mechanism 111 such as a motor. The projection optical system 120 has an optical element 125, and the optical characteristics of the projection optical system 120 may be adjusted by a drive mechanism 110 serving as an adjustment mechanism 150 driving the optical element 125. The drive mechanisms 110 and 111 are controlled by a projection system control device 106, which is controlled by a main control device 103.

[0019] The substrate 114 is held by a substrate stage 115, which can be driven by a substrate driving mechanism 109 in the X-, Y-, and Z-axis directions and in rotation about these axes. The substrate driving mechanism 109, which drives the substrate stage 115, and the original driving mechanism 108, which drives the original stage 113, can be controlled by a stage controller 107, which is controlled by the main controller 103. In scanning exposure, the stage controller 107 controls the original driving mechanism 108 and the substrate driving mechanism 109 so that the substrate stage 115 and the original stage 113 are scanned synchronously. The substrate stage 115 is provided with a movable mirror 117. A laser interferometer 116 (measuring instrument) detects the displacement of the movable mirror 117 in the X-, Y-, and Z-axis directions, thereby detecting the positions of the substrate stage 115 in the X-, Y-, and Z-axis directions and the rotation angles about these axes. The stage control device 107 can feedback control the position and rotation angle of the substrate stage 115 based on the detection results of the laser interferometer 116. Instead of the laser interferometer 116, other measuring instruments such as an encoder may be provided.

[0020] The projection optical system 119 and the detection optical system 118 constitute a focus detection system. The projection optical system 119 projects a plurality of light beams onto the substrate 114, the light beams having wavelengths that do not expose the photoresist of the substrate 114, and the light reflected from the substrate 114 enters the detection optical system 118. The detection optical system 118 is provided with light receiving elements that receive the plurality of light beams, and can detect the receiving positions of each of the plurality of light beams. The position of the substrate 114 in the Z-axis direction of the projection optical system 120 is detected as a positional deviation of the light beams received by the light receiving elements.

[0021] FIG. 2 schematically shows an alignment system included in the exposure apparatus 100. The exposure apparatus 100 may include one or more first mark detection devices 200 that detect the positions of alignment marks provided on the substrate 114 while moving the substrate 114. The exposure apparatus 100 preferably includes two first mark detection devices 200 that are spaced a predetermined distance apart in the X direction. The first mark detection devices 200 include an imaging unit 210 that is arranged between the illumination optical system 122 and the original stage 113. The exposure apparatus 100 preferably includes a drive mechanism that drives each imaging unit 210 of the one or more first mark detection devices 200 along the XY plane. The one or more first mark detection devices 200 may be configured to be able to observe alignment marks provided in shot areas of the substrate 114 and alignment marks provided on the original 112. The one or more first mark detection devices 200 can observe alignment marks provided in shot areas of the substrate 114 via the projection optical system 120. The main control device 103 (controller) can be configured to control the process of transferring the pattern of the original 112 to the substrate 114 based on the positions of the alignment marks detected by the first mark detection devices 200.

[0022] The exposure apparatus 100 may include one or more second mark detection devices, at least a portion of which is arranged between the projection optical system 120 and the substrate 114. In the example of FIG. 2, two second mark detection devices 128 and 129 are shown, but the exposure apparatus 100 may include more second mark detection devices. The exposure apparatus 100 may include a drive mechanism that drives the second mark detection devices 128 and 129 in the XY plane. Therefore, the second mark detection devices 128 and 129 may be configured to observe each of alignment marks provided in different shot areas of the substrate 114. The exposure apparatus 100 can simultaneously detect the positions of multiple marks by aligning the positions of the first mark detection device 127 and the second mark detection devices 128 and 129 with alignment marks formed on the substrate 114.

[0023] Below, we will explain the configuration and operation for detecting the position of the alignment mark on substrate 114 by first mark detection device 200 while moving substrate 114, but second mark detection devices 128 and 129 may also be configured and controlled in a similar manner.

[0024] The imaging unit 210 of the first mark detection apparatus 200 may include a light source 211 for illuminating the alignment mark and an image sensor 213 for capturing an image of the alignment mark. The light source 211 may include, for example, a light-emitting element such as an LED. The image sensor 213 may include a CCD or CMOS sensor with a global shutter function. The imaging unit 210 may also include an optical system (alignment scope) that forms an image of the alignment mark provided on the substrate 114 on the imaging surface of the image sensor 213. The imaging unit 210 may also include a light source driver 212 that drives the light source 211 and a sensor driver 214 that drives the image sensor 213. The light source driver 212 and the sensor driver 214 may be disposed between the illumination optical system 122 and the original stage 113, or may be disposed elsewhere.

[0025] The imaging unit 210 of the first mark detection apparatus 200 may include an imaging control unit 220 that controls the imaging unit 210 in synchronization with the substrate stage 115. The light source driver 212 and the sensor driver 214 may be incorporated into the imaging control unit 220, which will be described later. The imaging conditions for the imaging unit 210 to capture an image of the alignment mark on the substrate 114 are changeable, and the imaging control unit 220 may be configured to issue an imaging command to the imaging unit 210 at a timing corresponding to the imaging conditions. The imaging conditions for the imaging unit 210 to capture an image of the alignment mark on the substrate 114 may be, for example, the emission brightness of the light source 211 (or a command value for the emission intensity sent to the light source driver 212). Alternatively, the imaging conditions may be at least one of the speed and acceleration of the substrate stage 115, the imaging time (accumulation time) of the image sensor 213, and the magnification of the optical system (alignment scope). Alternatively, the imaging conditions may be other conditions that affect the imaging of the alignment mark.

[0026] The imaging control unit 220 can calculate the positions of the alignment marks based on images of the alignment marks captured while the substrate 114 is moved. Here, when calculating the positions of the alignment marks, the imaging control unit 220 uses the captured images of the alignment marks as well as the position of the substrate stage 115 at the time the alignment marks are captured. The calculation function of the imaging control unit 220 as described above may be incorporated into the main control device 103. The main control device 103 can perform a global alignment calculation that calculates the arrangement of the multiple shot areas on the substrate 114 and the shape of each shot area based on the detection results of the positions of the multiple alignment marks. However, the global alignment calculation may be performed by the imaging control unit 220.

[0027] The direction of movement of substrate 114 when imaging the alignment mark may be the X direction, the Y direction, or a direction that combines movement in the X direction and movement in the Y direction. From another perspective, movement of substrate 114 when imaging the alignment mark may be along a straight line in the XY plane, or along a curved line in the XY plane. Furthermore, imaging of the alignment mark may be performed when substrate 114 is moving at a constant velocity (constant speed), or when moving with positive or negative acceleration.

[0028] The stage control device 107 can provide the imaging control unit 220 with drive control information for controlling the drive of the substrate stage 115. The imaging control unit 220 can extract or generate imaging conditions (e.g., the speed or acceleration of the substrate stage 115) from the drive control information and issue an imaging command for imaging to the imaging unit 210 at timing corresponding to the extracted imaging conditions. The imaging control unit 220 can determine the timing for issuing an imaging command to the imaging unit 210 based on all or part of the imaging conditions obtained from the drive control information, the light emission brightness of the light source 211, the imaging time (accumulation time) of the image sensor 213, etc. If the speed or acceleration at which the substrate stage 115 is moved is changed, the imaging control unit 220 can change the timing for issuing an imaging command to the imaging unit 210 in accordance with the change. This makes it possible to detect the position of an alignment mark provided on a substrate with high accuracy under various imaging conditions.

[0029] The imaging control unit 220 can be configured to transition the signal for the imaging command at a timing having a delay time according to the imaging conditions relative to the timing when the substrate stage 115 reaches a predetermined position. The predetermined position is a position of the substrate stage 115 calculated backward from the timing when the signal for the imaging command should transition based on the delay time. The imaging control unit 220 can determine the delay time corresponding to the set imaging conditions by referring to a table that holds multiple pieces of delay time information corresponding to multiple imaging conditions, respectively.

[0030] 5, all or part of the functions of the imaging control unit 220 may be incorporated into the stage control device 107. In this case, the exposure apparatus 100 may include an image processing unit 230 that processes images of the alignment marks that are captured by the image sensor 213 and read out by the sensor driver 214. However, the functions of the image processing unit 230 may also be incorporated into the main control device 103.

[0031] FIG. 3 shows a timing chart of typical signals in the alignment system of the exposure apparatus 100. In FIG. 3, the trigger signal, exposure command, image sensor operation, and lighting command are shown in an activated low level state. The stage control device 107 activates the trigger signal at the timing (trigger timing) when the substrate stage 115 reaches a predetermined position. The timing when the substrate stage 115 reaches the predetermined position may be determined based on a position command value that the stage control device 107 provides to the substrate driving mechanism 109, or may be determined based on the output of the laser interferometer 116 (measuring instrument). The trigger signal is a signal supplied from the stage control device 107 to the imaging control unit 220.

[0032] The imaging control unit 220 may activate an exposure command at a first timing having a first delay time corresponding to the current imaging conditions relative to a trigger timing at which the trigger signal is activated. The exposure command is a signal supplied from the imaging control unit 220 to the sensor driver 214 of the imaging unit 210, i.e., a signal for controlling the accumulation period. The imaging control unit 220 maintains the exposure command (first signal) in an activated state for a predetermined accumulation period (accumulation time), and then deactivates the exposure command. The accumulation period may be understood as both an exposure period and an imaging period. The imaging control unit 220 may activate a lighting command (second signal) at a second timing having a second delay time corresponding to the current imaging conditions relative to a trigger timing at which the trigger signal is activated. The lighting command is a signal supplied from the imaging control unit 220 to the light source driver 212 of the imaging unit 210, i.e., a signal for controlling the lighting of the light source 211. The imaging control unit 220 maintains the exposure command in an activated state for a predetermined lighting period (lighting time), and then deactivates the exposure command. It is preferable to make the length of the lighting period (lighting time) as short as possible in order to suppress heat generation from the light source 211. Suppressing heat generation from the light source 211 can contribute to improving the accuracy of detecting the position of the alignment mark and / or increasing the degree of freedom in arranging the light source 211.

[0033] The sensor driver 214 can cause the image sensor 213 to start capturing an image in response to activation of the exposure command, and can cause the image sensor 213 to stop capturing an image in response to deactivation of the exposure command. This operation is shown as "image sensor operation" in FIG. 3.

[0034] In response to activation of the lighting command, the light source driver 212 drives the light source 211 according to a preset lighting brightness. In response to activation of the lighting command, the light source driver 212 supplies a current having a magnitude corresponding to the preset lighting brightness to the light source 211. The light source 211 has a lighting delay according to the lighting brightness, and can emit light of a brightness according to the preset lighting brightness after the lighting delay.

[0035] The first delay time and the second delay time are predetermined times that overlap the imaging period and the lighting period under imaging conditions, and preferably, 80% or more, 90% or more, 95% or more, 98% or more, or 100% of the imaging period falls within the lighting period.

[0036] In the above description, both the first delay time and the second delay time are treated as controllable parameters, but either the first delay time or the second delay time may be treated as a fixed value, in which case the other of the first delay time and the second delay time is determined so that the imaging period and the lighting period overlap under the imaging conditions.

[0037] In one aspect, the imaging conditions may include information for controlling the light emission brightness of the light source 211. In this case, the imaging control unit 220 may transition a signal for an imaging command (an exposure command and / or a lighting command) at a timing that has a delay time corresponding to the information relative to the timing when the substrate stage 115 reaches a predetermined position.

[0038] Alternatively, the imaging conditions may include the driving state of the substrate stage 115 when imaging the alignment mark. In this case, the imaging control unit 220 may transition the imaging command (exposure command and / or lighting command) at a timing with a delay time corresponding to the driving state relative to the timing when the substrate stage 115 reaches a predetermined position.

[0039] Alternatively, the imaging conditions may include the speed of the substrate stage 115 when imaging the alignment mark. In this case, the imaging control unit 220 may transition the signal for imaging commands (exposure command and / or lighting command) at a timing that has a delay time according to the speed relative to the timing when the substrate stage 115 reaches a predetermined position.

[0040] Alternatively, the imaging conditions may include the acceleration of the substrate stage 115 when imaging the alignment mark. In this case, the imaging control unit 220 may transition the command (exposure command and / or lighting command) at a timing that has a delay time according to the acceleration relative to the timing when the substrate stage 115 reaches a predetermined position.

[0041] From one point of view, the imaging control unit 220 causes the imaging unit 210 to capture an image of the alignment mark while the substrate stage 115 is moving at a constant speed.

[0042] From another perspective, the imaging control unit 220 causes the imaging unit 210 to capture an image of the alignment mark during the period when the substrate stage 115 is moving at a positive acceleration.

[0043] From yet another perspective, the imaging control unit 220 causes the imaging unit 210 to capture an image of the alignment mark during the period when the substrate stage 115 is moving at a negative acceleration.

[0044] Here, an exemplary method for determining the first delay time and the second delay time according to the lighting luminance of the light source 211 as an imaging condition will be described. This determination method can be controlled, for example, by software installed in the main control device 103. The first delay time and the second delay time can be determined while the substrate stage 115 is stationary.

[0045] If the first delay time is DT1, the second delay time is DT2, and the difference between the first delay time DT1 and the second delay time DT2 is Δ, then DT1 = DT2 + Δ. In one example, the main control device 103 can determine the first delay time DT1 according to DT1 = DT2 + Δ by setting the second delay time DT2 to a fixed value (e.g., a minimum time) and determining Δ so that the accumulation period and the lighting period overlap. The minimum value of the second delay time DT2 can be determined by activating a lighting command in response to activation of a trigger signal (trigger timing) and measuring the delay time between the activation of the trigger signal and the activation of the lighting signal.

[0046] Next, main controller 103 stops substrate stage 115 and positions imaging unit 210 at a position where it can capture an image of the alignment mark on substrate 114. In this state, as shown in FIG. 4, main controller 103 causes imaging control unit 220 to activate a lighting command. Light source 211 emits light with a brightness corresponding to the lighting brightness after a lighting delay corresponding to the lighting brightness set in response to the activation of the lighting command. Meanwhile, imaging control unit 220 activates an exposure command at a timing when delay time d has elapsed since the activation of the lighting command, and causes image sensor 213 to start capturing an image of the alignment mark by sensor driver 2214 in accordance with the exposure command.

[0047] Main control device 103 repeats the above operation while changing delay time d. In this way, main control device 103 can obtain changes in the alignment mark image corresponding to changes in delay time d. Then, main control device 103 can determine the delay time d when the best alignment mark image (typically, the image with the highest contrast) is obtained as Δ. In this way, main control device 103 can determine first delay time DT1 according to DT1=DT2+Δ.

[0048] Fig. 6 shows an example configuration of the imaging control unit 220. The imaging control unit 220 may include, for example, a decision circuit 300, an exposure command generator 310, a lighting command generator 320, and a lamp signal generator 330. The imaging control unit 220 in Fig. 6 includes the exposure command generator 310 that generates an exposure command at variable timing and the lighting command generator 320 that generates a lighting command at variable timing. However, the exposure command generator 310 and the lighting command generator 320 may be replaced with circuits that generate commands at fixed timing.

[0049] The determination circuit 300 may be configured, for example, as a table or memory that receives a digital code indicating an imaging condition as an address and outputs digital delay time data DT1x, DT2x corresponding to the digital code. Fig. 7 shows a schematic diagram of the function of the determination circuit 300. In the example of Fig. 7, a digital code (1, 2, 3, etc.) indicating an imaging condition is input as an address and the determination circuit 300 outputs digital delay time data DT1x, DT2x corresponding to the digital code.

[0050] The ramp signal generator 330 generates a ramp signal RAMP in response to activation of a trigger signal supplied from the stage control device 107 .

[0051] The exposure command generator 310 may include a digital-to-analog converter 311, a comparator 312, and an output circuit 315. The digital-to-analog converter 311 converts the delay time data DT1x into an analog signal DT1_A. The comparator 312 compares the analog signal DT1_A, which is the output of the digital-to-analog converter 311, with a ramp signal RAMP. The output circuit 315 transitions a signal for an exposure command, which is one of the imaging commands, in response to the output of the comparator 312. The output circuit 315 may include, for example, a delay element 313 and a gate circuit 314. The delay element 313 delays the output of the comparator 312 and determines the pulse width of the exposure command. The gate circuit 314 is, for example, configured with an AND circuit, and generates a signal for an exposure command whose pulse width is determined by the activation timing of the output of the comparator 312 and the activation timing of the output of the delay element 313. Figure 8(a) illustrates the operation of the exposure command generator 310.

[0052] The lighting command generator 320 may include a digital-to-analog converter 321, a comparator 322, and an output circuit 325. The digital-to-analog converter 321 converts the delay time data DT2x into an analog signal DT2_A. The comparator 322 compares the analog signal DT2_A, which is the output of the digital-to-analog converter 321, with a ramp signal RAMP. The output circuit 325 transitions a signal for a lighting command, which is one of the imaging commands, in response to the output of the comparator 322. The output circuit 325 may include, for example, a delay element 323 and a gate circuit 324. The delay element 323 delays the output of the comparator 322 and determines the pulse width of the lighting command. The gate circuit 324 is, for example, configured with an AND circuit, and generates a signal for a lighting command whose pulse width is determined by the activation timing of the output of the comparator 322 and the activation timing of the output of the delay element 323. Figure 8(b) illustrates the operation of the lighting command generator 320.

[0053] Below, we will explain a method for manufacturing an article such as a semiconductor device or a display device using exposure apparatus 100, which is an example of a lithography apparatus, shown in Figure 1. The article manufacturing method includes a transfer step in which a pattern of an original is transferred to a substrate using lithography apparatus or exposure apparatus 100, and a processing step in which the substrate that has undergone the transfer step is processed to obtain an article.

[0054] The processing step may include, for example, a film-forming process, etching, etc. Typically, the transfer step is performed multiple times while changing the original and / or the lithography apparatus (exposure apparatus), and may be followed by a processing step.

[0055] This specification and the accompanying drawings include the following disclosure: (Item 1) A mark detection device that detects the position of an alignment mark provided on a substrate, a substrate stage that holds and moves the substrate; an imaging unit including a light source for illuminating the alignment mark and an image sensor for capturing an image of the alignment mark; an imaging control unit that controls the imaging unit in synchronization with the substrate stage, an imaging condition of the alignment mark by the imaging unit is changeable, and the imaging control unit issues an imaging command to the imaging unit at a timing according to the imaging condition; A mark detection device characterized by: (Item 2) the imaging control unit transitions the signal for the command at a timing having a delay time according to the imaging conditions with respect to a timing when the substrate stage reaches a predetermined position. 2. The mark detection device according to item 1, (Item 3) the signal includes a signal for controlling an accumulation period of the image sensor; 3. The mark detection device according to item 2, (Item 4) the signal includes a signal for controlling lighting of the light source; 3. The mark detection device according to item 2, (Item 5) the imaging control unit determines a delay time corresponding to the set imaging condition by referring to a table storing a plurality of pieces of delay time information corresponding to the plurality of imaging conditions, respectively; 5. The mark detection device according to any one of items 2 to 4, characterized in that: (Item 6) the signals include a first signal that controls an accumulation period of the image sensor and a second signal that controls light emission of the light source; the imaging control unit transitions a first signal at a first timing having a first delay time according to the imaging conditions relative to the timing when the substrate stage reaches the predetermined position, and transitions the second signal at a second timing having a second delay time according to the imaging conditions relative to the timing when the substrate stage reaches the predetermined position. 3. The mark detection device according to item 2, (Item 7) The imaging control unit includes: a determination circuit that determines delay time data according to the imaging conditions; a digital-to-analog converter that converts the delay time data into an analog signal; a comparator that compares an output of the digital-to-analog converter with a ramp signal; and an output circuit that transitions the signal for the command in response to an output of the comparator. 3. The mark detection device according to item 2, (Item 8) the determination circuit includes a table that stores a plurality of delay time data corresponding to a plurality of imaging conditions, 8. The mark detection device according to item 7, (Item 9) the imaging conditions include information for controlling the light emission luminance of the light source, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the information with respect to a timing at which the substrate stage reaches the predetermined position. 9. The mark detection device according to any one of items 2 to 8, characterized in that: (Item 10) the imaging conditions include a driving state of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the driving state with respect to a timing at which the substrate stage reaches the predetermined position. 9. The mark detection device according to any one of items 2 to 8, characterized in that: (Item 11) the imaging conditions include a speed of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the speed with respect to a timing at which the substrate stage reaches the predetermined position. 9. The mark detection device according to any one of items 2 to 8, characterized in that: (Item 12) the imaging conditions include an acceleration of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the acceleration with respect to a timing at which the substrate stage reaches the predetermined position. 9. The mark detection device according to any one of items 2 to 8, characterized in that: (Item 13) the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a constant velocity; 13. The mark detection device according to any one of items 1 to 12, characterized in that: (Item 14) the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a positive acceleration; 13. The mark detection device according to any one of items 1 to 12, characterized in that: (Item 15) the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a negative acceleration; 13. The mark detection device according to any one of items 1 to 12, characterized in that: (Item 16) A lithography apparatus that performs a process of transferring a pattern of an original onto a substrate, A mark detection device according to any one of items 1 to 15, a control unit that controls the processing based on the position of the alignment mark detected by the mark detection device; 1. A lithography apparatus comprising: (Item 17) A transfer step of transferring a pattern of the original onto a substrate by the lithography apparatus according to item 16; a processing step of obtaining an article by processing the substrate that has undergone the transfer step; A method for manufacturing an article, comprising:

[0056] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0057] 200: Mark detection device, 115: Substrate stage, 210: Imaging unit, 220: Imaging control unit

Claims

1. A mark detection device that detects the position of an alignment mark provided on a substrate, a substrate stage that holds and moves the substrate; an imaging unit including a light source for illuminating the alignment mark and an image sensor for capturing an image of the alignment mark; an imaging control unit that controls the imaging unit in synchronization with the substrate stage, an imaging condition of the alignment mark by the imaging unit is changeable, and the imaging control unit issues an imaging command to the imaging unit at a timing according to the imaging condition; A mark detection device characterized by:

2. the imaging control unit transitions the signal for the command at a timing having a delay time according to the imaging conditions with respect to a timing when the substrate stage reaches a predetermined position.

2. The mark detection device according to claim 1.

3. the signal includes a signal for controlling an accumulation period of the image sensor; 3. The mark detection device according to claim 2.

4. the signal includes a signal for controlling lighting of the light source; 3. The mark detection device according to claim 2.

5. the imaging control unit determines a delay time corresponding to the set imaging condition by referring to a table storing a plurality of pieces of delay time information corresponding to the plurality of imaging conditions, respectively; 3. The mark detection device according to claim 2.

6. the signals include a first signal that controls an accumulation period of the image sensor and a second signal that controls light emission of the light source; the imaging control unit transitions a first signal at a first timing having a first delay time corresponding to the imaging conditions with respect to a timing at which the substrate stage reaches the predetermined position, and transitions the second signal at a second timing having a second delay time corresponding to the imaging conditions with respect to the timing at which the substrate stage reaches the predetermined position.

3. The mark detection device according to claim 2.

7. The imaging control unit includes: a determination circuit that determines delay time data according to the imaging conditions; a digital-to-analog converter that converts the delay time data into an analog signal; a comparator that compares an output of the digital-to-analog converter with a ramp signal; and an output circuit that transitions the signal for the command in response to an output of the comparator.

3. The mark detection device according to claim 2.

8. the determination circuit includes a table that stores a plurality of delay time data corresponding to a plurality of imaging conditions, 8. The mark detection device according to claim 7.

9. the imaging conditions include information for controlling the light emission luminance of the light source, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the information with respect to a timing at which the substrate stage reaches the predetermined position.

3. The mark detection device according to claim 2.

10. the imaging conditions include a driving state of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the driving state with respect to a timing at which the substrate stage reaches the predetermined position.

3. The mark detection device according to claim 2.

11. the imaging conditions include a speed of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the speed with respect to a timing at which the substrate stage reaches the predetermined position.

3. The mark detection device according to claim 2.

12. the imaging conditions include an acceleration of the substrate stage when imaging the alignment mark, the imaging control unit transitions the signal for the command at a timing having a delay time corresponding to the acceleration with respect to a timing at which the substrate stage reaches the predetermined position.

3. The mark detection device according to claim 2.

13. the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a constant velocity; 13. The mark detection device according to claim 1, wherein the mark detection device is a mark detection device for detecting a mark on a substrate.

14. the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a positive acceleration; 13. The mark detection device according to claim 1, wherein the mark detection device is a mark detection device for detecting a mark on a substrate.

15. the imaging control unit causes the imaging unit to capture an image of the alignment mark during a period in which the substrate stage is moving at a negative acceleration; 13. The mark detection device according to claim 1, wherein the mark detection device is a mark detection device for detecting a mark on a substrate.

16. A lithography apparatus that performs a process of transferring a pattern of an original onto a substrate, A mark detection device according to any one of claims 1 to 12; a control unit that controls the processing based on the position of the alignment mark detected by the mark detection device; 1. A lithography apparatus comprising:

17. a transfer step of transferring a pattern of an original onto a substrate by the lithography apparatus according to claim 16; a processing step of obtaining an article by processing the substrate that has undergone the transfer step; A method for manufacturing an article, comprising:

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