CN111103765A

CN111103765A - Exposure apparatus and article manufacturing method

Info

Publication number: CN111103765A
Application number: CN201911033882.0A
Authority: CN
Inventors: 冈田隆; 水元一史
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2018-10-29
Filing date: 2019-10-29
Publication date: 2020-05-05
Anticipated expiration: 2039-10-29
Also published as: CN111103765B; KR20200049528A; JP7222659B2; KR102568839B1; JP2020071274A

Abstract

The invention relates to an exposure apparatus and an article manufacturing method. Provided is a technique advantageous for obtaining an enlarged focal depth in an exposure device that scans and exposes a substrate by tilting the substrate or the substrate relative to the image plane of a projection optical system. The exposure apparatus includes an illumination optical system that illuminates an original plate and a projection optical system that projects a pattern of the original plate onto a substrate, and exposes the substrate while scanning the original plate and the substrate in a state in which the original plate or the substrate is tilted with respect to an image plane of the projection optical system. The exposure device comprises: an adjusting unit that adjusts the tilt of the original plate or the substrate with respect to the image plane; and a control unit that controls the adjustment unit, wherein the control unit tilts the original plate or the substrate in a direction determined so as to reduce an error of a latent image formed on an imaging area of the substrate.

Description

Exposure apparatus and article manufacturing method

Technical Field

The present invention relates to an exposure apparatus and an article manufacturing method, and relates to an exposure apparatus that exposes a substrate in a state where, for example, a base plate or the substrate is inclined with respect to an image plane of a projection optical system, and an article manufacturing method that manufactures an article using the exposure apparatus.

Background

As a method for expanding the depth of Focus in an Exposure apparatus, a FLEX (Focus enhanced Exposure) method is known in which a pattern of a mask is imaged at different positions in the optical axis direction. When performing exposure by the FLEX method in a scanning exposure apparatus, a substrate or a mask is scan-driven in a state of being inclined with respect to an image plane of a projection optical system. In the exposure by the FLEX method, in order to obtain a uniform focal depth enlargement effect on the entire image plane of the projection optical system, it is necessary to make the aperture (slit) region of the illumination field diaphragm of the illumination optical system symmetrical with respect to a straight line along a direction orthogonal to the scanning direction. In exposure by the FLEX method, since the substrate stage is inclined, when the slit region is asymmetric, the defocus amount is changed at each position in the direction orthogonal to the scanning direction, and the effect of enlarging the focal depth uniformly in the imaging region cannot be obtained.

Patent document 1 proposes a technique of controlling coma aberration generated by changing the telecentricity between the near side and the rear side of the slit when the mask or the substrate is tilted, thereby making the effect of enlarging the depth of focus in the imaging region uniform.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2009-164296

Disclosure of Invention

Under the present circumstances, the effect of enlarging the depth of focus when performing exposure by the FLEX method using a scanning exposure apparatus is insufficient, and improvement is desired.

According to a1 st aspect of the present invention, there is provided an exposure apparatus including an illumination optical system for illuminating an original plate and a projection optical system for projecting a pattern of the original plate onto a substrate, the exposure apparatus exposing the substrate while scanning the original plate and the substrate in a state where the original plate or the substrate is tilted with respect to an image plane of the projection optical system, the exposure apparatus comprising: an adjusting unit that adjusts the tilt of the original plate or the substrate with respect to the image plane; and a control unit that controls the adjustment unit, wherein the control unit tilts the original plate or the substrate in a direction determined so as to reduce an error of a latent image formed on an imaging area of the substrate.

According to a2 nd aspect of the present invention, there is provided an article manufacturing method characterized by comprising: exposing a substrate using the exposure apparatus according to claim 1; and developing the substrate exposed in the step, and manufacturing an article from the developed substrate.

According to the present invention, for example, there is provided a technique advantageous for obtaining an enlarged depth of focus in an exposure apparatus that performs scanning exposure of a substrate by inclining the substrate or the substrate with respect to the image plane of a projection optical system.

Drawings

Fig. 1 is a diagram illustrating a configuration of a scanning exposure apparatus in an embodiment.

Fig. 2 is a view illustrating exposure by the FLEX method.

Fig. 3 is a diagram showing a relationship between the shape of the slit region and the defocus amount.

Fig. 4 is a diagram illustrating a method of calculating a defocus coefficient.

Fig. 5 is a flowchart illustrating a process of determining the tilt direction of the substrate during FLEX exposure in the embodiment.

Fig. 6 is a diagram for explaining the process of determining the tilt direction of the substrate in the FLEX exposure in the embodiment.

Fig. 7 is a flowchart showing a process of determining the tilt direction of the substrate during FLEX exposure in the embodiment.

Fig. 8 is a diagram for explaining the process of determining the tilt direction of the substrate in the FLEX exposure in the embodiment.

Fig. 9 is a graph showing an example of aberration for each of a plurality of tilt amounts of a substrate.

Fig. 10 is a diagram showing an example of distortion degrees due to the inclination of the substrate with respect to each of the plurality of inclination amounts of the substrate.

Fig. 11 is a diagram illustrating an arrangement of a plurality of imaging regions on a substrate and a sequence of exposure.

(description of reference numerals)

IL: an illumination optical system; PO: a projection optical system; 17: original plate (master); and RS: an original plate objective table; 19: a tilting table; 20: a substrate; WS: a substrate stage; 30: a control unit; 32: a memory; 50: a scanning exposure device.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments merely show specific examples of the practice of the present invention, and the present invention is not limited to the following embodiments. All combinations of features described in the following embodiments are not necessarily required to solve the problems of the present invention.

< embodiment 1 >

Fig. 1 is a diagram showing a schematic configuration of a scanning exposure apparatus 50 according to the present embodiment. The scanning exposure apparatus 50 is configured to scan and expose the substrate 20 by projecting the pattern of the original plate 17 onto the substrate 20 by the projection optical system PO while scanning the original plate (which may also be referred to as a mask or a reticle) 17 and the substrate 20.

In this specification, directions are shown in an XYZ orthogonal coordinate system in which a horizontal plane is an XY plane, an axis parallel to the optical axis AX of the projection optical system PO is a Z axis, and directions orthogonal to the Z axis are an X axis and a Y axis. Directions parallel to the X, Y, and Z axes are referred to as X, Y, and Z directions, respectively.

The illumination optical system IL in this embodiment is configured by elements disposed on an optical path from the light source 1 to the collimator lens 16. As the light source 1, for example, ArF excimer laser having an oscillation wavelength of about 193nm and KrF excimer laser having an oscillation wavelength of about 248nm are used, but the type of light source and the wavelength of light emitted from the light source are not limited in the present invention.

The light emitted from the light source 1 is guided to the diffractive optical element 3 by the relay optical system 2. Typically, the plurality of diffractive optical elements 3 are mounted in respective grooves of a turntable having a plurality of grooves, and any diffractive optical element 3 can be disposed in the optical path by the actuator 4.

The light emitted from the diffractive optical element 3 is condensed by the condenser lens 5, and a diffraction pattern is formed on the diffraction pattern surface 6. The shape of the diffraction pattern can be changed by replacing the diffractive optical element 3 located in the optical path with the actuator 4.

The diffraction pattern formed on the diffraction pattern surface 6 is adjusted in parameters such as the zone ratio and the σ value by the prism group 7 and the zoom lens 8, and then enters the mirror 9. The light beam reflected by the mirror 9 is incident on the optical integrator 10. The optical integrator 10 can be configured as a lens array (fly eye), for example.

The prism 7 group includes, for example, a prism 7a and a prism 7 b. In the case where the distance between the

prisms

7a and 7b is sufficiently small, the

prisms

7a and 7b can be regarded as an integrated one-piece glass plate. The diffraction pattern formed on the diffraction pattern surface 6 is formed into an image on the incident surface of the optical integrator 10 by adjusting the σ value with the zoom lens 8 while keeping a substantially similar shape. By separating the positions of the

prisms

7a and 7b, the zone ratio and the opening angle of the diffraction pattern formed on the diffraction pattern surface 6 are also adjusted.

The light flux emitted from the optical integrator 10 is condensed by the condenser lens 11, and a desired light intensity distribution is formed on the surface 13 conjugate to the original plate 17. The illumination field diaphragm (light blocking member) 12 is disposed at a position deviated from the surface 13 conjugate to the surface on which the original plate 17 is disposed, defines an illumination region of the original plate 17 by the exposure light, and controls a light intensity distribution in the illumination region. More specifically, the light-shielding member 12 controls the light intensity distribution of the exposure light so that the light intensity distribution along the scanning direction of the original plate 17 and the substrate 20 is trapezoidal. The trapezoidal light intensity distribution is effective for reducing the variation in the cumulative exposure amount in the scanning direction caused when the light generated by the light source 1 is pulsed light, that is, when there is discontinuity.

The light flux having passed through the opening (slit) of the illumination field diaphragm 12 illuminates the original plate 17 via the collimator lens 14, the mirror 15, and the collimator lens 16. The pattern of the original plate 17 is projected by the projection optical system PO onto the substrate 20 held by the substrate stage WS including the tilt table 19. Thereby, a latent image pattern is formed on the photosensitive agent on the substrate 20.

The tilt table 19 positions the substrate 20 so that the substrate 20 is scanned in a state where the surface of the substrate 20 thus held is tilted with respect to the image plane of the projection optical system PO. The inclination of the tilt table 19 (i.e., the inclination of the substrate 20) is adjusted by an adjusting portion 21 including a tilt mechanism. The original plate 17 may be inclined without inclining the substrate 20, and here, a structure in which the substrate 20 is inclined may be adopted. In the example shown in fig. 1, the scanning direction is a direction along the Y axis, and the axis for controlling the tilt of the substrate 20 or the original plate 17 is rotation (ω X) around the X axis in order to increase the depth of focus.

The projection optical system PO includes a drive mechanism 25, and the drive mechanism 25 changes the aberration of the projection optical system PO by moving, rotating, and/or deforming at least 1 lens 24 among a plurality of lenses constituting the projection optical system PO. The drive mechanism 25 can include, for example, a mechanism that moves the lens 24 in a direction along the optical axis AX of the projection optical system PO, and a mechanism that rotates the lens 24 about an axis parallel to two axes (X-axis, Y-axis) perpendicular to the optical axis AX. The sensitivity of the aberration change with respect to the driving of the lens 24 may be determined in advance by calculation or actual measurement, and characteristic data (for example, a table) indicating the sensitivity may be stored in the memory 32 of the control unit 30. The control unit 30 can determine the driving amount of the lens 24 based on the characteristic data, and drive the lens 24 in accordance with the driving amount.

The control unit 30 controls each part of the scanning exposure device 50. The control unit 30 includes a memory 32 storing a program and data, and executes the control program stored in the memory 32 to perform scanning exposure.

The FLEX method is a method of performing multiple exposures with focus offset to improve contrast and enlarge depth of focus. When the scan exposure apparatus 50 performs the scan exposure by the FLEX method, the original plate 17 and the substrate 20 are respectively scan-driven in the directions indicated by arrows as shown in fig. 2. Hereinafter, the substrate 20 is described as being scan-driven. In this case, when the substrate 20 is exposed by the FLEX method, the substrate 20 is scan-driven so that each point of the substrate 20 is defocused → optimally focused → defocused on the image plane side of the projection optical system PO. For example, the controller 30 controls the substrate stage WS so that the point on the surface of the substrate 20 through which the optical axis AX passes coincides with the best focus position of the projection optical system PO. The substrate stage WS is controlled by the controller 30 so that the substrate 20 is inclined to the target.

Referring to fig. 3, exposure by the FLEX method is explained. In exposure by the FLEX method, multiple exposures can be continuously performed at a plurality of imaging positions in the vicinity of a BF plane by inclining the movement direction of the substrate stage with respect to the optimal focus plane (BF plane). Here, the inclination amount of the substrate stage is the same as the inclination amount of the movement direction of the substrate stage. In such exposure by the FLEX method, in order to obtain a uniform focal depth expansion effect on the entire image plane of the projection optical system PO, it is necessary that the aperture (slit) region of the illumination field diaphragm 12 is substantially rectangular as shown in fig. 3 (a 1). When the slit region is rectangular, the slit width is the same at each position (i1, i2, i3) in the direction (X direction) orthogonal to the scanning direction. In this case, even if the substrate is tilted by the tilt amount M by the tilt table 19 as shown in fig. 3 (a2), the defocus amount at each position (i1, i2, i3) can be uniformly generated within the imaging region (Df1 ═ Df2 ═ Df 3).

On the other hand, in order to correct the illuminance unevenness, the slit region may also have an asymmetrical shape with respect to a straight line along a direction orthogonal to the scanning direction. For example, a shape in which the slit width of the slit region differs at each position (i1, i2, i3) (hereinafter also referred to as "slit position") in the direction orthogonal to the scanning direction as shown in fig. 3 (B1) is considered. In this case, as shown in fig. 3 (B2), the defocus amount changes for each position within the imaging region due to the tilt of the substrate by the tilt table 19 (Df1 ≠ Df3 ≠ Df 2). In the example of fig. 3 (B2), the defocus amount at the position i2 is + Df2 on the + Df side from the tilt axis center, whereas the defocus amounts at the positions i1, i2 are + Df1, + Df3 are increased. Therefore, the effect of uniform focal depth enlargement in the imaging region cannot be obtained.

The FLEX method is a method of continuously performing multiple exposures at a plurality of imaging positions near the best focus plane, and therefore, errors in latent images formed on the imaging area occur with overlapping of projection images after defocusing. In the exposure apparatus, there is an error that cannot be removed even in the optical characteristics of the apparatus (asymmetry of slit shape, telecentricity, image plane) or in the apparatus adjustment state. Further, when exposure by the FLEX method is performed, an error due to inclination of the substrate may occur in a latent image formed on the imaging region, and the error may increase. Therefore, the FLEX method cannot obtain the originally expected effect of focal depth enlargement. The present embodiment addresses such a problem.

In the present embodiment, the control unit 30 determines the direction of inclination of the substrate 20 so as to reduce the error of the latent image formed on the imaging region between the next case (a) and the next case (B), and controls the adjustment unit 21. (A) The imaging region is exposed in a state where the substrate 20 is tilted in the 1 st direction.

(B) The imaging region is exposed in a state where the substrate 20 is inclined in the 2 nd direction opposite to the 1 st direction.

Specific examples are described below. Errors in the latent image formed on the shot area can be observed as positional deviation of the latent image, distortion degree, errors in line width, and the like. Therefore, the error of the latent image can be any error among, for example, a positional deviation, a distortion degree, and a line width error of the latent image. Hereinafter, the error of the latent image is determined according to the positional deviation of the latent image (hereinafter, also referred to as "deviation of the latent image").

First, a method of calculating a defocus coefficient for calculating the amount of occurrence of a positional deviation will be described with reference to fig. 4. The defocus coefficient is a value depending on the width of each position in the direction orthogonal to the scanning direction of the slit formed by the illumination field diaphragm 12. In fig. 4, Ai and Bi represent distances from the center of the tilt axis at the slit position i to the slit end. At this time, the defocus coefficient Ki indicating the ratio of the defocus amount at the slit position i is expressed by the following equation.

Ki＝Bi/Ai

It is desirable that no aberration is expected in the projection optical system, but in reality, an aberration (adjustment residual) that is not completely adjusted exists. The influence of the aberration can be observed as, for example, a positional deviation of the latent image as shown in fig. 6 (a). Such positional deviation also occurs in normal exposure in which the substrate is not tilted. Further, in the exposure by the FLEX method (FLEX exposure) which is performed in anticipation of the focal depth enlargement, a positional deviation Pm as shown in (B) and (D) of fig. 6 may newly occur depending on a combination of the inclination amount of the substrate and the asymmetry of the slit width as shown in (B2) of fig. 3. Due to such positional deviation, as if the aberration of the projection optical system increases, the deviation from the ideal imaging increases. Therefore, in the present embodiment, the tilt direction of the substrate in the FLEX exposure is determined based on the deviation of the latent image in the normal exposure in which the imaging region is exposed without tilting the substrate and the deviation of the latent image due to tilting the substrate.

Fig. 5 shows a flowchart of the process of determining the inclination amount of the substrate in the present embodiment, in S11, the control unit 30 acquires the deviation L of the latent image in the case of performing the normal exposure (1 st error), in S12, the control unit 30 obtains the deviation Pm1 (2 nd error) due to the inclination of the latent image formed on the imaging region in the case of exposing the imaging region in the state where the substrate is inclined α μ rad in the 1 st direction as the inclination amount M of the substrate, and calculates the deviation Pm1 of the latent image generated in principle due to the slit shape from the deviation Om1 and the defocus coefficient Ki of the latent image generated due to the inclination amount M of the substrate at that time by the following equation.

Pm1＝Ki·Om1

The control unit 30 obtains a deviation Pm2 (error No. 3) due to the inclination of the latent image formed on the imaging region when the imaging region is exposed in a state where the substrate is inclined α [ μ rad ] in the 2 nd direction opposite to the 1 st direction as the inclination amount M of the substrate, and calculates the deviation Pm2 of the latent image generated in principle due to the slit shape from the deviation Om2 of the latent image and the defocus coefficient Ki generated due to the inclination amount M of the substrate at that time by the following equation.

Pm2＝Ki·Om2

Fig. 6 (B) shows a deviation pm1 of a latent image generated when the FLEX exposure is performed with the inclination α [ μ rad ] in the + direction (1 st direction) as the inclination amount M of the substrate, fig. 6 (D) shows a deviation pm2 of a latent image generated when the FLEX exposure is performed with the inclination α [ μ rad ] in the-direction (2 nd direction) as the inclination amount M of the substrate, and thus the sign of the deviation of the latent image is reversed depending on the direction of the inclination of the substrate.

In S13, the control unit 30 obtains L + Pm1 (1 st synthesis error) in which the deviation L (1 st error) of the latent image by the synthetic adjustment residual and the deviation Pm1 (2 nd error) of the latent image in the case of tilting α [ μ rad ] in the 1 st direction (C) of fig. 6), and the control unit 30 obtains L + Pm 567 (2 nd synthesis error) in which the deviation Pm2 (2 nd error) of the latent image in the case of tilting α [ μ rad ] in the 2 nd direction (E) of fig. 6 in the case of synthesizing the adjustment residual (E) and the control unit 30 determines the tilt control of the substrate in the tilt direction (e.g., the tilt control unit 3519 determines the tilt control of the substrate in the tilt direction (Pm) of the substrate in accordance with the comparison result of the 1 st synthesis error and the 2 nd synthesis error (E) and the tilt control unit 30 determines the tilt control amount of the tilt control of the tilt of the substrate in the respective tilt directions (Pm) of the tilt directions (E3519, 356, 3519, 366).

< embodiment 2 >

In embodiment 1, the error of the latent image is determined according to the positional deviation of the latent image formed on the photographing region, but in embodiment 2, the error of the latent image is determined according to the distortion degree of the latent image formed on the photographing region. In embodiment 2, from the viewpoint of the degree of distortion, an offset component generated for each image height in the X direction due to a defocus amount and a telecentric component generated when FLEX exposure is performed in an exposure apparatus in which the slit shape is asymmetric as in (B2) of fig. 3 is considered.

It is desirable that no distortion is expected in the lens of the projection optical system, but in reality, there is an unadjusted distortion (adjustment residual) N as shown in fig. 8 a. This distortion degree also occurs in normal exposure in which the substrate is not tilted. Further, in the FLEX exposure performed in anticipation of the focal depth enlargement, the distortion degree Qm shown in (B) and (D) of fig. 8 may newly occur depending on the combination of the inclination amount of the substrate and the asymmetry of the slit width as shown in (B2) of fig. 3. Therefore, in the present embodiment, the tilt direction of the substrate during FLEX exposure is determined based on the distortion degree during normal exposure in which the substrate is not tilted and the distortion degree due to substrate tilting.

Fig. 7 is a flowchart of the process of determining the substrate tilt amount in the present embodiment. In S21, the control unit 30 acquires the distortion factor N in the normal exposure. In S22, the control unit 30 calculates a distortion Qm due to the slit shape, which is generated in principle, based on the distortion Rm generated by the inclination amount M of the substrate and the defocus coefficient Ki, by the following equation.

Qm＝Ki·Rm

Fig. 8 (B) shows the distortion qm1 that occurs when the FLEX exposure is performed with the substrate tilt amount M set to + β [ μ rad ], and fig. 8 (D) shows the distortion qm2 that occurs when the FLEX exposure is performed with the substrate tilt amount M set to- β [ μ rad ].

The influence of the distortion factor at the time of actual exposure is obtained by adding the adjustment residual distortion factor N and the distortion factor Qm generated at the time of FLEX exposure. In actual production, it is necessary to reduce the degree of distortion in shooting. Therefore, in S23, the control unit 30 calculates the distortion degree of each of N + Qm1 ((C) of fig. 8) and N + Qm2 ((E) of fig. 8), and determines the tilt direction so that the absolute value of the distortion degree in the shooting becomes smaller. In S24, the control unit 30 drives the tilt table 19 to tilt the substrate in accordance with the determined tilt direction.

< embodiment 3 >

Fig. 9 is a graph showing an example of an error of a latent image due to the inclination of the substrate with respect to each of the plurality of inclination amounts of the substrate. In the present embodiment, for example, data according to the graph is stored in advance in the memory 32 of the control unit 30. The control unit 30 obtains an error Om generated by the set substrate inclination amount M from the data stored in the memory 32. The control unit 30 calculates an error Pm which is generated in principle due to the slit shape by the following equation based on the obtained error Om and the defocus coefficient Ki.

Pm＝Ki·Om

The control section 30 adds the calculated error Pm to the characteristic data as a lens control parameter. The lens control parameter can include, for example, a Z position, a tilt amount around the X axis, a tilt amount around the Y axis, and the like, in addition to Pm. The control unit 30 drives the lens 24 of the projection optical system PO by the drive mechanism 25 to correct the error Pm as the lens control parameter, and performs the FLEX exposure.

< embodiment 4 >

Fig. 10 is a diagram showing an example of distortion degrees due to the inclination of the substrate with respect to each of the plurality of inclination amounts of the substrate. In the present embodiment, for example, the distortion data according to the figure is stored in advance in the memory 32 of the control unit 30. The control unit 30 obtains a distortion degree Rm generated by the inclination amount M of the substrate from the distortion degree data stored in the memory 32. The control unit 30 calculates a distortion Qm which is generated in principle due to the slit shape, from the obtained distortion Rm and the defocus coefficient Ki, by the following equation.

Qm＝Ki·Rm

The control unit 30 adds the calculated distortion Qm to the characteristic data as a lens control parameter. The lens control parameters can include, for example, a Z position, a tilt amount around the X axis, a tilt amount around the Y axis, and the like, in addition to Qm. The control unit 30 drives the lens 24 of the projection optical system PO by the drive mechanism 25 so as to correct the distortion Qm as a lens control parameter, and performs FLEX exposure.

< embodiment 5 >

In the above embodiment, the case where the inclination of the substrate 20 is adjusted so that the error of the latent image is reduced for 1 imaging region has been described. Therefore, the control unit 30 can adjust the tilt of the substrate by the adjustment unit 21 for each of the plurality of imaging regions arranged in the substrate 20. This can provide a uniform focal depth expansion effect in each imaging region, and can improve exposure accuracy.

However, if the tilt is to be adjusted separately for a plurality of shot areas on the substrate, the yield may be degraded. Therefore, the control unit 30 may adjust the tilt of the substrate by the adjustment unit 21 for each group in which the exposure order is continuous and the scanning direction is the same among the plurality of imaging regions arranged on the substrate 20, and may set the tilt adjustment state to be constant within each group. For example, a plurality of imaging regions are generally arranged in a matrix on a substrate, and the scanning direction of each imaging region, the exposure order of each imaging region, and the path of movement of the substrate between the imaging regions are predetermined as exposure conditions. Fig. 11 shows an example of a plurality of imaging regions arranged in a matrix on a substrate. In scanning exposure, generally, from the viewpoint of throughput, the exposure order is set in a serpentine shape from the imaging region at one end of the substrate as shown in fig. 11. In this case, the shooting area group in one line is an example of a group in which the exposure order is continuous and the scanning directions are the same. This can suppress a decrease in yield due to adjustment of the inclination of the substrate.

In one embodiment, the control unit 30 has, as the exposure control mode, an accuracy priority mode that can be selected by the user and that gives priority to, for example, exposure accuracy and a yield priority mode that gives priority to yield. When the accuracy priority mode is selected, the adjustment unit 21 adjusts the tilt of the substrate for each of the plurality of imaging regions arranged in the substrate 20. On the other hand, when the throughput priority mode is selected, the adjustment unit 21 adjusts the tilt of the substrate for each group of the plurality of imaging regions in which the exposure order is continuous and the scanning direction is the same, and the adjustment state of the tilt of the substrate is fixed in each group.

< embodiment of method for producing article >

The article manufacturing method according to the embodiment of the present invention is suitable for manufacturing articles such as micro devices such as semiconductor devices and devices having a microstructure, for example. The method for manufacturing an article according to the present embodiment includes a step of forming a latent image pattern on a photosensitive agent applied to a substrate by using the exposure apparatus (a step of exposing the substrate), and a step of developing the substrate on which the latent image pattern has been formed in the step. Further, such a manufacturing method includes other known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, and the like). The method for manufacturing an article according to the present embodiment is advantageous in at least 1 of the performance, quality, productivity, and production cost of the article, as compared with the conventional method.

Claims

1. An exposure apparatus including an illumination optical system that illuminates an original plate and a projection optical system that projects a pattern of the original plate onto a substrate, the exposure apparatus exposing the substrate while scanning the original plate and the substrate in a state in which the original plate or the substrate is tilted with respect to an image plane of the projection optical system, the exposure apparatus comprising:

an adjusting unit that adjusts the tilt of the original plate or the substrate with respect to the image plane; and

a control section for controlling the adjusting section,

the control unit tilts the original plate or the substrate in a direction determined so as to reduce an error of a latent image formed on an imaging area of the substrate.

2. The exposure apparatus according to claim 1,

the control unit acquires a1 st error, which is an error of a latent image formed on the imaging area when the imaging area is exposed without tilting the original plate or the substrate,

the control unit obtains a2 nd error, the 2 nd error being an error caused by inclination of a latent image formed on the imaging area when the imaging area is exposed in a state where the original plate or the substrate is inclined in a1 st direction,

the control unit obtains a 3 rd error, wherein the 3 rd error is an error caused by inclination of a latent image formed on the imaging area when the imaging area is exposed in a state where the original plate or the substrate is inclined in a2 nd direction opposite to the 1 st direction,

the control unit determines a tilt direction of the original plate or the substrate based on a comparison result between a1 st resultant error obtained by combining the 1 st error and the 2 nd error and a2 nd resultant error obtained by combining the 1 st error and the 3 rd error.

3. The exposure apparatus according to claim 2,

the illumination optical system includes an illumination field aperture that defines an illumination area of the master,

the control unit obtains an error of the latent image according to a shape of the slit, which is calculated from an error of a latent image formed on the imaging region due to inclination of the substrate and a defocus coefficient depending on a width of each position of the slit formed by the illumination field stop in a direction orthogonal to the scanning direction, as the 2 nd error or the 3 rd error.

4. The exposure apparatus according to claim 2,

the control unit performs exposure while driving a lens included in the projection optical system so as to correct the 2 nd error or the 3 rd error.

5. The exposure apparatus according to claim 4,

the control unit obtains the 2 nd error and the 3 rd error from data of an error caused by the inclination of the substrate with respect to each of a plurality of inclination amounts of the substrate.

6. The exposure apparatus according to claim 1,

the control unit adjusts the tilt by the adjustment unit for each of a plurality of imaging regions arranged on the substrate.

7. The exposure apparatus according to claim 1,

the control unit adjusts the tilt by the adjustment unit for each group in which exposure orders are continuous and scanning directions are the same, the groups being arranged in a plurality of imaging regions of the substrate, and fixes the tilt adjustment state within each group.

8. The exposure apparatus according to claim 1,

the control unit includes, as exposure control modes, an accuracy priority mode that gives priority to exposure accuracy and a yield priority mode that gives priority to yield, and when the accuracy priority mode is selected, the tilt adjustment by the adjustment unit is performed for each of a plurality of imaging regions arranged on the substrate, and when the yield priority mode is selected, the tilt adjustment by the adjustment unit is performed for each group of the plurality of imaging regions in which the order of exposure is continuous and the scanning direction is the same, and the tilt adjustment state is fixed within each group.

9. The exposure apparatus according to claim 1,

the error of the latent image is any error among a positional deviation, a distortion degree, and a line width error of the latent image.

10. A method of manufacturing an article, comprising:

exposing a substrate using the exposure apparatus according to any one of claims 1 to 9; and

a step of developing the substrate exposed in the step,

fabricating an article from the developed substrate.