TWI847583B - Exposure device and method for manufacturing article - Google Patents

Abstract

An exposure device is provided, which is an exposure device for exposing the substrate while moving the original plate and the substrate in a scanning direction, and has an illumination optical system for illuminating the illuminated surface of the original plate with light from a light source, wherein the illumination optical system comprises: a first light shielding portion arranged at a position away from a concentric surface of the illuminated surface toward the light source, a second light shielding portion arranged at a position away from the concentric surface toward the illuminated surface, and a second light shielding portion arranged at a position away from the first light shielding portion. The shielding portion between the first light shielding portion and the second light shielding portion that delimits the illumination range of the illuminated surface, the sum of a first distance between the concentric plane and the first light shielding portion in the direction of the optical axis of the illumination optical system, and a second distance between the concentric plane and the second light shielding portion in the direction of the optical axis, is greater than 5 mm and less than 20 mm, and the first light shielding portion and the second light shielding portion are configured so that the first distance and the second distance become different.

Description

Exposure device and method for manufacturing article

The present invention relates to an exposure device and a method for manufacturing an article.

In the conventional exposure device, the illumination optical system illuminates the original plate (grating or mask), and the original plate pattern is projected onto the substrate (wafer) through the projection optical system. In the exposure device, high resolution is required to be achieved along with the miniaturization of semiconductor equipment. In order to achieve high resolution, the shortening of the wavelength of the exposure light, the increase of the aperture number (NA) of the projection optical system (high NA), and modified illumination (ring illumination, dipole illumination, quadrupole illumination, etc.) are effective.

On the other hand, with the multi-layered equipment structure in recent years, the exposure device is also required to improve the overlap accuracy. The exposure device of Patent Document 1 has: a shading portion arranged at a position defocused from the concentric surface of the illuminated surface of the exposure device toward the light source side, and a shading portion arranged at a position defocused from the concentric surface of the illuminated surface toward the illuminated surface side. The exposure device of Patent Document 1 is effective for improving the overlap accuracy. [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2010-73835

[The problem the invention is trying to solve]

However, the exposure device of Patent Document 1 has a drop in illumination due to the light shielding portion and asymmetry (XY asymmetry) in the integrated effective light source. If a large asymmetry occurs in the integrated effective light source, for example, when a line and space pattern with the same line width is transferred to a substrate in the longitudinal direction and the lateral direction, a line width difference occurs between the longitudinal pattern and the lateral pattern.

The present invention provides an exposure device that is beneficial for suppressing the decrease in illumination in the illuminated surface and the asymmetry in the integrated effective light source. [Technical means for solving the problem]

In order to achieve the above-mentioned purpose, an exposure device of one aspect of the present invention is an exposure device that exposes the substrate while moving the original plate and the substrate in a scanning direction, and has an illumination optical system that illuminates the illuminated surface of the original plate with light from a light source, and the illumination optical system includes: a first light shielding portion arranged at a position away from the concentric surface of the illuminated surface toward the light source, a second light shielding portion arranged at a position away from the concentric surface toward the illuminated surface, and a The shielding portion between the first shading portion and the second shading portion, which delimits the illumination range of the illuminated surface, has a sum of a first distance between the concentric plane and the first shading portion in the direction of the optical axis of the illumination optical system, and a second distance between the concentric plane and the second shading portion in the direction of the optical axis, which is greater than 5 mm and less than 20 mm, and the first shading portion and the second shading portion are configured so that the first distance and the second distance are different. [Effect of the invention]

According to the present invention, an exposure device can be provided, which is helpful in suppressing the decrease in illumination in the illuminated surface and the asymmetry in the integrated effective light source, for example.

Other features and advantages of the present invention will become more apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals are used for the same or similar structures.

The following detailed description of the embodiments is provided with reference to the attached drawings. The following embodiments are not intended to limit the scope of the patent application. Although multiple features are described in the embodiments, all of these multiple features are not necessarily required for the invention, and multiple features can be combined arbitrarily. Furthermore, in the attached drawings, the same reference number is added to the same or similar structure, and repeated description is omitted.

FIG. 1 is a schematic cross-sectional view showing the structure of an exposure device 100 of one embodiment of the present invention. The exposure device 100 is an exposure device (scanner) of a step-and-scan method that moves the original plate 25 and the substrate 27 in a scanning direction while exposing the substrate 27 (scanning exposure) to transfer the pattern of the original plate 25 onto the substrate. The exposure device 100 includes an illumination optical system 110 that illuminates the original plate 25 (grating or mask) with light from a light source 1, and a projection optical system 26 that projects the pattern of the original plate 25 onto the substrate 27 (wafer, glass plate, etc.).

The light source 1 includes a mercury bulb with a wavelength of about 365 nm, a KrF excimer laser with a wavelength of about 248 nm, an ArF excimer laser with a wavelength of about 193 nm, and the like, and emits a light beam (exposure light) for illuminating the original plate 25 .

The illumination optical system 110 includes: a path selection optical system 2, an emission angle preservation optical element 5, a diffraction optical element 6, a condenser 7, a light shielding member 8, a prism unit 10, and a zoom lens unit 11. In addition, the illumination optical system 110 includes: an optical integrator 12, an aperture 13, a condenser 14, a first light shielding portion 18, a second light shielding portion 20, a shielding unit 19, a condenser 21, and a collimating lens 23.

The routing optical system 2 is disposed between the light source 1 and the emission angle preservation optical element 5, and guides the light beam from the light source 1 to the emission angle preservation optical element 5. The emission angle preservation optical element 5 is disposed on the light source side of the diffraction optical element 6, and guides the light beam from the light source 1 to the diffraction optical element 6 while maintaining the divergence angle fixedly. The emission angle preservation optical element 5 is an optical integrator including a compound eye lens, a microlens array, and a fiber bundle. The emission angle preservation optical element 5 is used to reduce the light intensity distribution (pattern distribution) formed by the diffraction optical element 6, which affects the output variation of the light source 1.

The diffraction optical element 6 is arranged on a surface that forms a Fourier transform relationship with the pupil plane of the illumination optical system 110. The diffraction optical element 6 converts the light intensity distribution of the light beam from the light source 1 by diffraction, and forms a desired light intensity distribution on a surface conjugated with the pupil plane of the projection optical system 26, that is, the pupil plane of the illumination optical system 110 and a surface conjugated with the pupil plane of the illumination optical system 110. The diffraction optical element 6 can also be a computer generated hologram (CGH) designed by a computer so that a desired diffraction pattern can be obtained on the diffraction pattern surface. In this embodiment, the shape of the light source formed on the pupil plane of the projection optical system 26 is called the effective light source shape. In addition, "effective light source" means the light angle distribution in the illuminated surface and the conjugated surface of the illuminated surface. The diffraction optical element 6 is disposed between the emission angle preservation optical element 5 and the focusing lens 7 .

In the illumination optical system 110, a plurality of diffractive optical elements 6 may also be provided. For example, each of the plurality of diffractive optical elements 6 is respectively mounted (mounted) on one of the plurality of slits of the corresponding turntable (not shown). The plurality of diffractive optical elements 6 each form a different effective light source shape. These effective light source shapes include a small circular shape (a relatively small circular shape), a large circular shape (a relatively large circular shape), a ring shape, a dipole shape, a quadrupole shape, and other shapes. The method of illuminating the illuminated surface with an effective light source shape in the shape of a ring, a dipole, or a quadrupole is called deformed illumination.

The light beam from the output angle preservation optical element 5 is diffracted by the diffractive optical element 6 and guided to the condenser 7. The condenser 7 is disposed between the diffractive optical element 6 and the prism unit 10, collects the light beam diffracted by the diffractive optical element 6, and forms a diffraction pattern (light intensity distribution) on the Fourier transform surface 9.

The Fourier transform surface 9 is located between the optical integrator 12 and the diffractive optical element 6, and has an optical Fourier transform relationship with the diffractive optical element 6. By replacing the diffractive optical element 6 disposed in the optical path of the illumination optical system 110, the shape of the diffraction pattern formed on the Fourier transform surface 9 can be changed.

The light shielding member 8 is movable in a direction perpendicular to the optical axis 1b of the illumination optical system 110 and is arranged on the upstream side (light source side) of the Fourier transform surface 9. The light shielding member 8 is arranged at a position slightly away from the Fourier transform surface 9 (defocused).

The prism unit 10 and the zoom lens unit 11 are provided between the Fourier transform surface 9 and the optical integrator 12, and function as a zoom optical system that expands the light intensity distribution formed on the Fourier transform surface 9. The prism unit 10 adjusts the annularity and the like of the light intensity distribution formed on the Fourier transform surface 9 and guides it to the zoom lens unit 11. Furthermore, the zoom lens unit 11 is provided between the prism unit 10 and the optical integrator 12. The zoom lens unit 11, for example, includes a plurality of zoom lenses, and adjusts the σ value of the light intensity distribution formed on the Fourier transform surface 9 based on the ratio of the NA of the illumination optical system 110 and the NA of the projection optical system 26, and guides the light to the optical integrator 12.

The optical integrator 12 is disposed between the zoom lens unit 11 and the condenser 14. The optical integrator 12 includes a compound lens (fly-eye lens) that forms a plurality of secondary light sources and guides them to the condenser 14, with the light intensity distribution being adjusted corresponding to the annularity, the opening angle, and the σ value. However, the optical integrator 12 may also include other optical elements such as an optical tube, a diffractive optical element, and a microlens array instead of the compound lens (fly-eye lens). The optical integrator 12 uniformly illuminates the original plate 25 disposed on the illuminated surface 24 with the light beam passing through the diffractive optical element 6. An aperture 13 is provided between the optical integrator 12 and the condenser 14.

The condenser 14 is disposed between the optical integrator 12 and the original plate 25. Thus, the majority of light beams guided from the optical integrator 12 can be collected to illuminate the original plate 25 in a superimposed manner. When light is incident on the optical integrator 12 and collected by the condenser 14, the focal plane of the condenser 14, that is, the conjugate plane 19, is illuminated in a substantially rectangular shape.

A semi-reflecting mirror 15 is disposed in the rear section of the condenser mirror 14. A part of the exposure light reflected by the semi-reflecting mirror 15 is incident on the light quantity measuring optical system 16. A sensor 17 for measuring the light quantity is disposed in the rear section of the light quantity measuring optical system 16. The exposure quantity during exposure is appropriately controlled according to the light quantity measured by the sensor 17.

Specifically, between the first light shielding section 18 and the second light shielding section 20, a shielding unit (shielding section) 19 including X blades and Y blades is arranged on a surface coaxial with the illuminated surface 24, that is, a coaxial surface 19a or near the coaxial surface 19a, and is illuminated by a light intensity distribution in a substantially rectangular shape. In addition, near the coaxial surface 19a means that the X blades and Y blades of the shielding unit 19 are separated from the coaxial surface 19a by a necessary distance so that the X blades and Y blades do not interfere with each other, for example, about 0.2 mm away from the coaxial surface 19a in the optical axis direction. The shielding unit 19 is arranged to delimit the illumination range of the original plate 25 (the illuminated surface 24), and is scanned synchronously with the original plate stage 29 and the substrate stage 28. The original plate stage 29 is a stage for moving while holding the original plate 25 , and the substrate stage 28 is a stage for moving while holding the substrate 27 .

Two light shielding parts are provided at positions away (defocused) from the shielding unit 19 (the conjugate surface 19a of the illuminated surface 24). In the present embodiment, a first light shielding part 18 and a second light shielding part 20 are provided. The first light shielding part 18 is arranged at a position away from the conjugate surface 19a of the illuminated surface 24 toward the light source side. The second light shielding part 20 is arranged at a position away from the conjugate surface 19a of the illuminated surface 24 toward the illuminated surface side.

The light reflected by the mirror 22 having a predetermined inclination with respect to the light beam from the condenser 21 passes through the collimating lens 23 to illuminate the original plate 25 .

The projection optical system 26 projects the pattern of the original plate 25 onto the substrate 27. The resolution of the pattern of the original plate 25 depends on the shape of the effective light source. Therefore, by forming an appropriate effective light source distribution in the illumination optical system 110, the resolution of the pattern of the original plate 25 can be improved.

The first light shielding portion 18, the shielding unit 19, and the second light shielding portion 20 are described in detail with reference to Fig. 2. In Fig. 2, the y direction indicates the scanning direction. The shielding unit 19 includes scanning shielding blades 19d and 19e that move during scanning exposure.

As shown in FIG. 2, the first light-shielding portion 18 includes a first light-shielding member 18a and a second light-shielding member 18b. An end 18aA on the second light-shielding member side of the first light-shielding member 18a and an end 18bA on the first light-shielding member side of the second light-shielding member 18b are located within the effective light range, and the intensity of light reaching the illuminated surface 24 is adjusted by shielding a portion of the light. For example, an actuator (not shown) is connected to the first light-shielding member 18a. By moving the first light-shielding member 18a along the scanning direction (y direction) by means of such an actuator, the opening width limited by the end 18aA of the first light-shielding member 18a and the end 18bA of the second light-shielding member 18b can be changed. In this way, the first light-shielding portion 18 constitutes a variable slit. Furthermore, in the present embodiment, the first light shielding portion 18 is provided with a first moving unit FMU for moving the first light shielding member 18a and the second light shielding member 18b in the direction of the optical axis 1b of the illumination optical system 110.

As shown in FIG. 2, the second light-shielding portion 20 includes a third light-shielding member 20a and a fourth light-shielding member 20b. The end 20aA on the fourth light-shielding member side of the third light-shielding member 20a and the end 20bA on the third light-shielding member side of the fourth light-shielding member 20b are located within the effective light range, and the intensity of light reaching the illuminated surface 24 is adjusted by shielding a portion of the light. The third light-shielding member 20a is connected to an actuator (not shown). By moving the third light-shielding member 20a along the scanning direction (y direction) by means of this actuator, the opening width limited by the end 20aA of the third light-shielding member 20a and the end 20bA of the fourth light-shielding member 20b can be changed. In this way, the second light-shielding portion 20 constitutes a variable slit. Furthermore, in the present embodiment, the second light shielding unit 20 is provided with a second moving unit SMU for moving the third light shielding member 20a and the fourth light shielding member 20b in a direction along the optical axis 1b of the illumination optical system 110.

As shown in FIG. 2, in a plane including the optical axis 1b and parallel to the scanning direction, the first distance between the concentric surface 19a and the end 18aA of the first light shielding member 18a in the direction along the optical axis 1b is set to d1. Also, in a plane including the optical axis 1b and parallel to the scanning direction, the second distance between the concentric surface 19a and the end 20aA of the third light shielding member 20a in the direction along the optical axis 1b is set to d2. In this case, the first distance d1 and the second distance d2 are different values. Furthermore, the distance between the conjugate surface 19a and the end 18bA of the second light shielding member 18b is equal to the first distance d1, and the distance between the conjugate surface 19a and the end 20bA of the fourth light shielding member 20b is equal to the second distance d2. Thus, the first light shielding portion 18 and the second light shielding portion 20 are arranged so that the first distance d1 and the second distance d2 are different.

As shown in FIG. 2, in a plane including the optical axis 1b and parallel to the scanning direction, the midpoint between the end 18aA of the first light shielding member 18a and the end 18bA of the second light shielding member 18b is set to 18c. Similarly, the midpoint between the end 20aA of the third light shielding member 20a and the end 20bA of the fourth light shielding member 20b is set to 20c. The distance from the midpoint 18c to the end 18aA of the first light shielding member 18a and the end 18bA of the second light shielding member 18b is set to S1, and the distance from the midpoint 20c to the end 20aA of the third light shielding member 20a and the end 20bA of the fourth light shielding member 20b is set to S2. In this case, the distance S1 and the distance S2 are different values. Furthermore, a straight line connecting the midpoint 18c and the midpoint 20c is parallel to the optical axis 1b.

Referring to Fig. 3a and Fig. 3b, the integrated effective light source is explained. In Fig. 3a and Fig. 3b, the y direction is the display scanning direction. Fig. 3a shows the illumination area 24e of the illuminated surface 24, and Fig. 3b shows the illumination area 19b of the conjugate surface 19a (shielding unit 19) that is in a conjugate relationship with the illuminated surface 24.

When exposure is performed, the illumination area 24e is scanned. At this time, the incident angle distribution of illuminating a certain point on the exposure surface is the cumulative incident angle distribution of illuminating each point of the straight line 24f parallel to the scanning direction (y direction) in the illumination area 24e, which is called the integrated effective light source. Since the straight line 19c is a collection of points conjugated with each point of the straight line 24e in the conjugated surface 19a, the integrated effective light source is equivalent to the cumulative incident angle distribution of the light beams passing through each point of the straight line 19c illuminating the illumination surface 24.

The functions of the first light shielding portion 18 and the second light shielding portion 20 are explained with reference to Fig. 4a, Fig. 4b and Fig. 4c. In Fig. 4a, Fig. 4b and Fig. 4c, the y direction indicates the scanning direction. Fig. 4a is an enlarged view of the vicinity of the optical integrator 12, the condenser 14, the first light shielding portion 18 and the second light shielding portion 20. Fig. 4a shows light rays emitted from the optical integrator 12, passing through the condenser 14 and passing through points A, B and C on the concentric surface 19a. Here, points A, B and C are points on the straight line 19 shown in Fig. 3b. Fig. 4b is a diagram showing effective light sources 24a, 24b and 24c at each of points A', B' and C' on the illuminated surface 24. Each of the points A', B' and C' is in a conjugate relationship with the points A, B and C of the conjugate plane 19a of the illuminated surface 24. FIG. 4c is a diagram showing the integrated effective light source 24d after all the light rays passing through the straight line including the points A', B' and C' of the illuminated surface 24 are accumulated.

In addition, in the present embodiment, in order to facilitate the understanding of the invention, the effective light source is described as a circular shape of conventional lighting, but it can be formed into a ring shape, a multipole shape, etc. according to the combination of the prism unit 10 and the diffractive optical element 6. The present invention is not limited to the shape of the effective light source formed by the diffractive optical element 6 and the prism unit 10.

Referring to FIG. 4a, the light 12a emitted from the optical integrator 12 in parallel with the optical axis 1b, passing through the condenser lens 14, and heading toward the point A of the conjugate surface 19a is not shielded by the first shielding portion 18 and the second shielding portion 20. Therefore, the effective light source 24a at the point A' of the illuminated surface 24 is almost circular and almost symmetrical in the scanning direction as shown in FIG. 4b.

On the other hand, a portion of the light 12b that is emitted obliquely from the optical integrator 12 toward the first light shielding member side relative to the optical axis 1b, passes through the condenser 14, and heads toward the point B on the conjugate surface 19a is shielded by the first light shielding member 18a and the third light shielding member 20a. Therefore, the effective light source 24b at the point B' of the illuminated surface 24 is a shape that is missing at both ends in the scanning direction with respect to the circle, and has asymmetry (XY asymmetry) between the distribution in the x direction (direction perpendicular to the y direction) and the distribution in the y direction.

Furthermore, a portion of the light 12c emitted from the optical integrator 12 toward the second light shielding member side relative to the optical axis 1b, passing through the condenser 14, and heading toward the point C of the conjugate surface 19a is shielded by the second light shielding member 18b and the fourth light shielding member 20b. Therefore, the effective light source 24c at the point C' of the illuminated surface 24 is a shape that is missing at both ends in the scanning direction with respect to the circle, and has asymmetry (XY asymmetry) between the distribution in the x direction (direction perpendicular to the y direction) and the distribution in the y direction.

Thus, if we consider the integrated effective light source 24d obtained by accumulating all the light beams on the straight line including points A, B and C, the integrated effective light source 24d has XY asymmetry as shown in FIG. 4c.

Referring to Fig. 5a and Fig. 5b, the structure for reducing the XY asymmetry of the integrated effective light source 24d is described. Fig. 5a is a diagram showing the illumination distribution 24ee (illumination area 24e) of the illuminated surface 24 formed by the light beam illuminating the conjugate surface 19a at the maximum angle θ0. The distribution of the conjugate surface 19a is imaged on the illuminated surface 24 by the focusing lens 21 and the collimating lens 23 at the imaging magnification β.

The maximum incident angle of the light beam illuminating the conjugate surface 19a is set to θ0. The first distance S1 and the second distance S2 are determined so that the light beam passing through the end 18aA of the first light shielding member 18a at an angle of θ0 and the light beam passing through the end 20aA of the third light shielding member 20a at an angle of -θ0 intersect at a point 19aa of the conjugate surface 19a. As described above, the first distance S1 is the distance from the midpoint 18c to the end 18aA of the first light shielding member 18a, and the second distance S2 is the distance from the midpoint 20c to the end 20aA of the third light shielding member 20a. The point where the straight line connecting the end 18aA of the first light shielding member 18a and the end 20aA of the third light shielding member 20a intersects the conjugate surface 19a is denoted by 19bb, and the distance between the point 19bb and the point 19cc is denoted by S. The points of the illuminated surface 24 corresponding to the points 19aa, 19bb and 19cc of the conjugate surface 19a are denoted by 24g, 24h and 24i.

In the illuminated surface 24, the light illuminating the area inside the point 24g is not shielded by the first light shielding member 18a and the third light shielding member 20a, so its intensity becomes constant. In addition, in the illuminated surface 24, the light illuminating the area outside the point 24h is shielded by the first light shielding member 18a and the third light shielding member 20a, so its intensity becomes zero. The other end of the illumination distribution 24ee is shielded by the second light shielding member 18b and the fourth light shielding member 20b, and has the same shape. Therefore, the illumination distribution 24ee has a shape close to a trapezoid. The lower base and the upper base of this trapezoid are set to w0 and w100, respectively.

The effective light source that illuminates the point between the point 24i and the point 24g of the illuminated surface 24 is almost circular, similar to the effective light source in the above-mentioned point A'. The effective light source that illuminates the point between the point 24g and the point 24h of the illuminated surface 24 has a large XY asymmetry, similar to the effective light source in the above-mentioned point B'. In addition, since the point between the point 24g and the point 24h of the illuminated surface 24 is shielded by both the first shielding portion 18 and the second shielding portion 20, a decrease in illumination occurs. Therefore, by increasing the ratio of w100 to w0 and reducing the distance between the point 24g and the point 24h, the decrease in illumination and the occurrence of XY asymmetry of the integrated effective light source 24d can be suppressed.

The lower base w0 of the illumination distribution 24ee is expressed as w0=2βS. On the other hand, the upper base w100 of the illumination distribution 24ee is expressed as w100= 2β(S1-d1×tanθ0)=2β(S2-d2×tanθ0). Therefore, the ratio w100/w0 of the upper base w100 to the lower base w0 is expressed as w100/w0=(S1-d1×tanθ0)/S=(S2-d2×tanθ0)/S.

Points 19aa and 19bb of the conjugate surface 19a are represented by the points where the straight line passing through the end 18aA of the first light shielding member 18a intersects the conjugate surface 19a. Therefore, in the case of d1＜d2, w100/w0 is closer to 1 as d1 is smaller, and becomes 1 when d1=0. Also, in the case of d1＞d2, w100/w0 is closer to 1 as d2 is smaller, and becomes 1 when d2=0.

As described above, scanning shielding blades 19d and 19e are arranged between the first light shielding portion 18 and the second light shielding portion 20. Since the scanning shielding blades 19d and 19e are moved during scanning exposure, a certain degree of space is necessary. Therefore, the distance between the first light shielding portion 18 and the second light shielding portion 20 in the direction along the optical axis 1b cannot be smaller than the specified value D. The specified value D is expressed as D=d1+d2 using the first distance d1 between the first light shielding portion 18 and the conjugate surface 19a and the second distance d2 between the second light shielding portion 20 and the conjugate surface 19a. Generally, the specified value D is greater than 5 mm and less than 20 mm.

FIG. 5b is a diagram showing the illumination distribution 24ee of the illuminated surface 24 formed by the light beam illuminating the concentric surface 19a at the maximum angle θ0 when the first distance d1 and the second distance d2 are equal. Since the condition D=d1+d2 is met, the first distance d1 shown in FIG. 5b is larger than the first distance d1 shown in FIG. 5a. Therefore, w100/w0 becomes smaller as shown in FIG. 5b.

The following describes specific numerical examples of the first light shielding portion 18 and the second light shielding portion 20. When D=8[mm], S=5[mm], and θ0=0.4[rad], the relationship between w100/w0 and d1/d2 is as shown in FIG6. In FIG6, the vertical axis shows w100/w0 and the horizontal axis shows d1/d2. As shown in FIG6, the relationship between w100/w0 and d1/d2 is expressed by a quadratic equation, and becomes the minimum when d1=d2.

If the integrated effective light source 24d has XY asymmetry, the illumination will decrease if the XY asymmetry is corrected. In order to reduce the decrease in illumination, if the XY asymmetry needs to be reduced to 15% or less, w100/w0 is preferably greater than 0.7. Referring to FIG. 6, it can be seen that in order to make w100/w0 greater than 0.7, d2/d1>2 or d2/d1<1/2 is necessary.

Next, referring to FIG. 7, the conditions for the maximum and minimum values of d2/d1 are explained. Points C' and B' shown in FIG. 4b, which correspond to the inclined portion of the illumination distribution 24ee, have a light center drift (deviation of the center of gravity light) in the scanning direction. Light center drift is not good because it affects the overlap accuracy, but it can be controlled by the ratio of d1 and d2.

FIG. 7 is a known structure of conventional lighting, specifically, the light center drift in this embodiment is shown when the light center drift is set to 1 only in the structure in which a shading portion is arranged on the upstream side of the conjugate surface of the illuminated surface. In FIG. 7, the vertical axis shows the light center drift, and the horizontal axis shows d1/d2. Referring to FIG. 7, the light center drift becomes the minimum value when d1/d2=1, specifically, it becomes 0. This means that the light center drift will not occur. In order to improve the overlap accuracy, the light center drift is preferably less than half of the known structure in which a shading portion is arranged on the upstream side of the conjugate surface of the illuminated surface. Referring to FIG. 7 , it can be seen that in order to shift the center of gravity of the light beam to less than half of the known structure, 1/4＜d2/d1＜4 is necessary.

Therefore, in order to satisfy the conditions of the first distance d1 from the conjugate surface 19a to the first light shielding portion 18 and the second distance d2 from the conjugate surface 19a to the second light shielding portion 20, d1≠d2, preferably 1/4＜d2/d1＜1/2 or 2＜d2/d1＜4. Thus, one of the first distance d1 and the second distance d2 is greater than twice the other, and preferably less than four times.

In the present embodiment, as described above, an actuator for moving the first light shielding member 18a in the scanning direction and a first moving unit FMU for moving the first light shielding portion 18 (the first light shielding member 18a and the second light shielding member 18b) in the direction along the optical axis 1b are provided. Similarly, an actuator for moving the third light shielding member 20a in the scanning direction and a second moving unit SMU for moving the second light shielding portion 20 (the third light shielding member 20a and the fourth light shielding member 20b) in the direction along the optical axis 1b are provided. By having such a driving mechanism, the most suitable d1, d2, S1 and S2 can be set according to the illumination mode, and the drift of the center of gravity of the light, the decrease in illumination, and the XY asymmetry in the effective light source can be further reduced (suppressed).

The manufacturing method of the article in the embodiment of the present invention is optimal for the manufacture of articles such as flat panel displays, liquid crystal display elements, semiconductor elements, MEMS, etc. This manufacturing method includes: a process of exposing a substrate coated with a photosensitive agent using the above-mentioned exposure device 100, and a process of developing the exposed photosensitive agent. In addition, the substrate is subjected to an etching process and an ion implantation process using the developed photosensitive agent pattern as a mask to form a circuit pattern on the substrate. These processes of exposure, development, etching, etc. are repeated to form a circuit pattern composed of multiple layers on the substrate. In the subsequent process, the substrate with the circuit pattern formed is cut into blocks, and the chip assembly, bonding, and inspection processes are carried out. Moreover, this manufacturing method includes other well-known processes (oxidation, coating, evaporation, doping, planarization, protective layer stripping, etc.). The manufacturing method of the article in this embodiment can improve at least one of the performance, quality, productivity and production cost of the article compared with the known method.

The present invention is not limited to the above-mentioned embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Therefore, the claims are added to announce the scope of the invention.

1: Light source 1b: Optical axis 2: Path selection optical system 5: Emission angle preservation optical element 6: Diffraction optical element 7: Condenser 8: Shading component 9: Fourier transform surface 10: Prism unit 11: Zoom lens unit 12: Optical integrator 12a: Light 12b: Light 12c: Light 13: Aperture 14: Condenser 15: Semi-reflecting mirror 16: Light quantity measurement optical system 17: Sensor 18: First shading section 18a: First shading component 18aA: End 18b: Second shading component 18bA: End 18c: Midpoint 19: Shielding unit 19a: Conjugate surface 19aa, 19bb: Point 19b: Domain 19c: Line 19cc: Point 19d: Scanning shielding blade 20: Second shading unit 20a: Third shading member 20aA: End 20b: Fourth shading member 20bA: End 20c: Midpoint 21: Condenser 22: Mirror 23: Collimator 24: Illuminated surface 24a, 24b: Effective light source 24c: Effective light source 24d: Effective light source 24e: Domain 24ee: Distribution 24f: Line 24g: Point 24h: Point 24i: Point 25: Original plate 26: Projection optical system 27: Substrate 28: Substrate stage 29: Original plate stage 100: Exposure device 110: Illumination optical system

The accompanying drawings are included in the specification and constitute a part of the specification, and are used to show the embodiments of the present invention and explain the principle of the present invention together with the description in the specification. [Figure 1] A schematic cross-sectional view showing the structure of an exposure device of one embodiment of the present invention. [Figure 2] A diagram for explaining the details of the first light shielding part, the shielding unit and the second light shielding part. [Figure 3] A diagram for explaining the integrated effective light source. [Figure 4] A diagram for explaining the functions of the first light shielding part and the second light shielding part. [Figure 5] A diagram for explaining the structure for reducing the XY asymmetry of the integrated effective light source. [Figure 6] A diagram for explaining specific numerical examples related to the first light shielding part and the second light shielding part. [Figure 7] A diagram for explaining specific numerical examples related to the first light shielding part and the second light shielding part.

18a: The first shading component

18aA: End

18b: Second light-shielding component

18c: midpoint

19a: Conjugate surface

19aa: point

19bb: points

19cc: point

20a: The third shading component

20aA: End

20b: The fourth shading component

20c: midpoint

24: Illuminated surface

24ee: Distribution

24g: point

24h: o'clock

24i: point

Claims (7)

An exposure device for exposing the substrate while moving the original plate and the substrate in a scanning direction, characterized in that: it has an illumination optical system for illuminating the illuminated surface of the original plate with light from a light source, and the illumination optical system includes: a first light shielding portion arranged at a position away from a concentric surface of the illuminated surface toward the light source, and a second light shielding portion arranged at a position away from the concentric surface toward the illuminated surface. The light section, and the shielding section disposed between the first light shielding section and the second light shielding section to define the illumination range of the illuminated surface, wherein a first distance between the concentric plane and the first light shielding section in the direction of the optical axis of the illumination optical system, and a second distance between the concentric plane and the second light shielding section in the direction of the optical axis, one of the distances is greater than 2 times and less than 4 times the other distance. As in claim 1, the exposure device, wherein the sum of the first distance and the second distance is greater than 5 mm and less than 20 mm. The exposure device of claim 1 further comprises: a first moving part for moving the first light shielding part in a direction along the optical axis, and a second moving part for moving the second light shielding part in a direction along the optical axis. The exposure device of claim 3, wherein the illumination optical system comprises: an optical part that changes the light angle distribution formed on the illuminated surface in the illumination optical system, and the first light shielding part and the second light shielding part are moved using the first moving part and the second moving part in accordance with the light angle distribution after the optical part changes. As in the exposure device of claim 1, the shielding portion is arranged on the conjugate surface or in the vicinity of the conjugate surface. As in the exposure device of claim 1, each of the first light shielding portion and the second light shielding portion includes a variable slit. A method for manufacturing an article, comprising: a process of exposing a substrate using an exposure device as claimed in claim 1, a process of developing the exposed substrate, and a process of manufacturing an article from the developed substrate.

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