JP5103995B2 - Exposure method and apparatus, and device manufacturing method - Google Patents

Description

  The present invention relates to an exposure technique used for transferring a predetermined pattern onto a substrate such as a wafer, and more particularly to an exposure technique using an illumination technique related to so-called modified illumination. The present invention further relates to a device manufacturing technique using the exposure technique.

  In a lithography process for manufacturing a device such as a semiconductor element or a liquid crystal display element (electronic device or microdevice), a pattern of a reticle (or photomask) is transferred onto a wafer (or glass plate or the like) as a substrate to be exposed. For this purpose, a batch exposure type exposure apparatus such as a stepper or a scanning exposure type exposure apparatus such as a scanning stepper is used. In this type of exposure apparatus, exposure methods using various illumination methods have been proposed in order to transfer various patterns onto a wafer with high resolution while ensuring a sufficient depth of focus.

For example, when the pattern to be transferred is an isolated pattern substantially consisting of a single aperture, the illumination light is emitted from one relatively small circular area centered on the optical axis on the pupil plane of the illumination optical system of the exposure apparatus. An illumination method that increases the amount of light, that is, an illumination method (small σ illumination method) that relatively reduces the coherence factor (σ value) of the illumination optical system is effective. In addition, when the pattern to be transferred is a dense pattern arranged in two orthogonal directions with a fine cycle (pitch), in order to transfer the dense pattern onto the wafer with a deep focal depth and high resolution. On the pupil plane of the illumination optical system, a modified illumination method (modified light source method) comprising so-called quadrupole illumination is effective in which the amount of illumination light is increased in four regions that are decentered obliquely with respect to the optical axis. For example, see Patent Document 1).
JP 2001-176766 A

  Recently, as a pattern to be transferred, a pattern in which a dense pattern having periodicity in a predetermined direction and a plurality of line patterns arranged in a predetermined direction with a period larger than the period of the dense pattern is used. There is. In this case, the illumination light for the dense pattern should have a large numerical aperture, whereas the illumination light for the line pattern can be defocused if the numerical aperture is increased as much as the illumination light for the dense pattern. There has been a problem that the fluctuation of the intensity distribution of the transferred image becomes large. Therefore, when transferring the two types of patterns onto the wafer at the same time, there is a possibility that a sufficient depth of focus cannot be secured.

In view of the above, an object of the present invention is to provide an exposure technique capable of simultaneously and successfully transferring a plurality of periodic patterns having different periods or intervals onto a substrate.
Another object of the present invention is to provide a device manufacturing technology that can manufacture a device having a plurality of patterns formed at various periods or intervals with high accuracy and efficiency using the exposure technology. To do.

An exposure method according to the present invention illuminates a pattern with a light beam from the illumination system (12), and exposes the substrate with the light beam through the pattern and the projection system (PL). and (X direction) periodically formed first pattern (32XA), and a second pattern formed by a cycle longer than the cycle of the first pattern in a first direction (34X), the projection An aperture stop (AS) through which a second-order diffracted light generated from the second pattern can pass when a light beam from the illumination system is incident on the second pattern substantially perpendicularly to the system. A first and second region (41A, 41B) disposed substantially symmetrically apart in a direction corresponding to the first direction with respect to the optical axis of the illumination system, the light amount distribution of the luminous flux on the predetermined surface (Q1); The light The light quantity in the four areas consisting of the third and fourth areas (42A, 42B) arranged substantially symmetrically in the direction corresponding to the second direction orthogonal to the first direction is the light quantity in the other areas. And the positions of the third and fourth regions are ± 1 out of 0th order light and diffracted light generated from the second pattern by the light flux from the third and fourth regions. It is set so that at least one of the second-order diffracted light and 0th-order light pass through the projection system, and second-order or higher-order diffracted light does not pass through the projection system .

An exposure apparatus according to the present invention illuminates a pattern with a light beam from the illumination system (12), and exposes the substrate with the light beam through the pattern and the projection system (PL). A light amount distribution setting mechanism (4, 21, 71, 72) for setting the light amount distribution of the luminous flux on the surface, and a control device (17) for controlling the light amount distribution setting mechanism in accordance with the pattern. The first pattern (32XA) periodically formed in the first direction (X direction) and the second pattern (34X) formed in the first direction with a period longer than the period of the first pattern. seen including, in the projection system, the light beam from the illumination system when incident substantially perpendicularly to the second pattern, that is generated from the second pattern second-order diffracted light aperture passable opening (aS) is arranged When you are, the control unit controls the light intensity distribution setting mechanism, the light amount distribution of the light beam in the predetermined plane, away almost symmetrically in a direction corresponding to the first direction with respect to the optical axis of the illumination system The first and second regions (41A, 41B) arranged and the third and fourth regions (a and b) arranged substantially symmetrically apart in a direction corresponding to the second direction orthogonal to the first direction with respect to the optical axis ( 42A, 42B) is set so that the light quantity in the four areas is larger than the light quantity in the other areas, and the positions of the third and fourth areas are set to the luminous fluxes from the third and fourth areas. Among the 0th-order light and diffracted light generated from the second pattern, at least one of the ± 1st-order diffracted light and 0th-order light pass through the projection system, and the second-order or higher-order diffracted light is projected. Go through the system It is set so that there is no.

The device manufacturing method of the present invention is a device manufacturing method including a lithography process, and a pattern is transferred to a photoreceptor using the exposure method or exposure apparatus of the present invention in the lithography process.
In addition, although the reference numerals in parentheses attached to the predetermined elements of the present invention correspond to members in the drawings showing an embodiment of the present invention, each reference numeral of the present invention is provided for easy understanding of the present invention. The elements are merely illustrative, and the present invention is not limited to the configuration of the embodiment.

According to the exposure method and apparatus of the present invention, the first pattern is illuminated by the modified illumination method with illumination light having a large numerical aperture from the first and second regions, and the substrate is satisfactorily (high resolution and deep). Transferred at depth of focus.
Further, since the third and fourth regions are separated from the optical axis of the illumination system in the direction corresponding to the second direction (direction orthogonal to the periodic direction), the third and fourth regions of the illumination light from the third and fourth regions are separated. The numerical aperture for one direction (periodic direction) is substantially reduced. Accordingly, the second pattern rougher than the first pattern is favorably transferred onto the substrate by the illumination light from the third and fourth regions.

Hereinafter, a preferred first embodiment of the present invention will be described with reference to FIGS.
FIG. 1A shows the configuration of a scanning exposure type exposure apparatus (projection exposure apparatus) comprising the scanning stepper of this example. In FIG. 1A, the exposure apparatus includes an exposure light source 1 and an exposure light source. An illumination optical system 12 that illuminates a reticle R on which a transfer pattern is formed with illumination light IL (exposure light beam or exposure beam) from a light source 1; a reticle stage system that controls the position and speed of the reticle R; Projection optical system PL for projecting a pattern image of reticle R onto wafer W coated with a photoresist (photosensitive material) as a substrate, wafer stage system for controlling the position and speed of wafer W, and operation of the entire apparatus And a main control system 17 composed of a computer for overall control. An ArF excimer laser light source (wavelength 193 nm) is used as the exposure light source 1.

As the exposure light source 1, a laser light source such as a KrF excimer laser light source (wavelength 248 nm), an F ₂ laser light source (wavelength 157 nm), a mercury lamp, a harmonic generation light source of a YAG laser, or a solid-state laser (for example, a semiconductor laser) Harmonic generators such as can also be used. Hereinafter, the Z-axis is parallel to the optical axis AX of the projection optical system PL, and the non-scanning direction (here, the paper surface of FIG. 1A) orthogonal to the scanning direction of the reticle R and the wafer W in a plane perpendicular to the Z-axis. In the following description, the X axis is taken in the direction parallel to the Y axis, and the Y axis is taken in the scanning direction (here, the direction perpendicular to the paper surface of FIG. 1A).

  The illumination light IL composed of ultraviolet pulse light emitted from the exposure light source 1 is converted into a desired shape by the beam expander 2 and then along the optical axis BX via the optical path bending mirror 3. Then, the light enters the first diffractive optical element 21 and has a predetermined light amount distribution on a predetermined surface (in this example, the exit surface of the fly-eye lens 5 and equal to the pupil plane Q1 of the illumination optical system 12) as described later. It is converted into a light beam DL that is diffracted in a plurality of directions so as to be obtained. The diffractive optical element 21 is attached to a revolver 24 that is rotated by a drive unit 23. The revolver 24 also includes a second diffractive optical element 22 having other diffraction characteristics and other diffractive optical elements (not shown). It is attached. The main control system 17 controls the rotation angle of the revolver 24 via the drive unit 23 and installs any one of the diffractive optical elements 21, 22, etc. on the optical path of the illumination light IL, so that illumination conditions (illumination optics) The light amount distribution of the illumination light IL on the pupil plane of the system 12 can be switched.

  As an example, the diffractive optical element 21 can be manufactured by forming an uneven grating having regularity in two directions on a light-transmitting substrate. The diffractive optical element 21 may be a combination of a plurality of phase type diffraction gratings. In these cases, since the diffractive optical element 21 is a phase type, there is an advantage that the light use efficiency is high. As the diffractive optical element 21, it is possible to use an optical element in which the refractive index distribution is changed by a diffraction grating distribution. The structure and manufacturing method of a diffractive optical element having specific diffraction characteristics are disclosed in detail in, for example, Japanese Patent Application Laid-Open No. 2001-176766 by the present applicant.

  In FIG. 1A, a light beam DL diffracted by the diffractive optical element 21 is collected by a relay lens 4 and passes through a first prism 71 and a second prism 72 (movable prism), and a fly-eye lens as an optical integrator. 5 is focused on the incident surface. In this case, the diffractive optical element 21 is arranged at a position slightly shifted to the exposure light source 1 side from the front focal point of the relay lens 4, and the incident surface of the fly-eye lens 5 is substantially at the position of the rear focal point of the relay lens 4. Has been placed. A plurality of light beams diffracted from the diffractive optical element 21 in different directions are collected in different regions on the entrance surface of the fly-eye lens 5, and the exit surface (exit-side focal plane) of the fly-eye lens 5 is collected. ) Is formed with a surface light source (in this example, a secondary light source composed of a large number of light source images) having a distribution substantially corresponding to the light amount distribution on the incident surface. The exit plane is the pupil plane Q1 of the illumination optical system 12, and the exit plane of the diffractive optical element 21 and the exit plane of the fly-eye lens 5 (pupil plane Q1) are combined by a synthetic lens system including the relay lens 4 and the fly-eye lens 5. ) Is almost conjugate (imaging relationship).

  In this example, the light quantity distribution setting system (including the relay lens 4, the diffractive optical element 21, the first prism 71, and the second prism 72) for setting the illumination light IL on the predetermined surface to a predetermined light quantity distribution ( Molding optical system). Note that this shaping optical system may also include a zoom optical system (for example, an afocal system). For example, the coherence factor (σ value) can be continuously changed. Further, for example, a replaceable aperture stop may be disposed on the predetermined surface or its conjugate surface, and a light amount distribution having a special shape may be set while suppressing loss of light amount in combination with the diffractive optical element. Note that the predetermined plane on which the light quantity distribution is set may be a conjugate plane with the pupil plane Q1 or a plane in the vicinity thereof.

  As shown in FIG. 1 (B), the first prism 71 in FIG. 1 (A) becomes a parallel plane plate 71a in a circular area centered on the optical axis BX of the illumination optical system 12, and is concave in the periphery. The second prism 72 is a member that becomes a conical body 71 b, and the concave and convex portions are reversed with respect to the first prism 71 and constitutes a plane-parallel plate as a whole when combined with the first prism 71. The light beam that passes through the conical portions (slopes) around the prisms 71 and 72 passes through a plurality of areas where the light amount is increased on the exit surface Q1 of the fly-eye lens 5. In addition, at least one of the prisms 71 and 72, for example, in this example, only the second prism 72 is supported by a drive mechanism (not shown) so as to be displaceable along the optical axis BX. In this example, the second prism 72 is displaced along the optical axis BX, and the interval between the prisms 71 and 72 is changed, thereby allowing a plurality of regions having a large amount of light on the exit surface (pupil plane Q1) of the fly-eye lens 5 to be changed. The position can be adjusted in the radial direction. That is, the positions of a plurality of regions in the orthogonal biaxial directions on the exit plane or pupil plane Q1 (predetermined plane) corresponding to the X and Y directions of the XY plane in which the pattern surface of the reticle R is arranged substantially in parallel. The (distance from the optical axis BX) is variable. In FIG. 1A, the orthogonal biaxial directions are the Y and Z directions, but in the following description, the periodic direction (arrangement direction) of the pattern of the reticle R on the XY plane and a plurality of regions on the pupil plane Q1 In order to clarify the correspondence with the arrangement and make the explanation easy to understand, the orthogonal biaxial directions on the pupil plane Q1 are also referred to as the X and Y directions in correspondence with the periodic direction of the pattern.

  Instead of the prisms 71 and 72, a prism in which the cone portion is a pyramid (or a pyramid shape), a prism having a hollow near the optical axis, or a plurality of portions processed separately and fixed integrally. Etc. may be used. Further, this position may be made variable along the optical axis BX by using only the first prism 71 without using the two prisms 71 and 72. Further, as the movable prism, as shown in FIG. 1 (C), a pair of V-shaped prisms 71A and 71B having a refractive power in one direction and no refractive power in a direction perpendicular thereto are used. May be.

  In this configuration, the distance between the prisms 71A and 71B can be changed in the vertical direction in FIG. 1C (for example, in the Y direction in FIG. 3A showing the light quantity distribution of illumination light on the pupil plane of the illumination optical system 12). The position (distance from the optical axis BX) of the region with a large amount of light with respect to the correspondence) changes. Furthermore, in order to adjust the position (distance from the optical axis BX) of a region with a large amount of light in a direction perpendicular to the direction (a direction perpendicular to the paper surface of FIG. 1C and corresponding to the X direction in FIG. 3A). Alternatively, another pair of prisms 71C and 71D having a configuration in which the pair of prisms 71A and 71B is rotated by 90 ° around the optical axis BX may be disposed. This makes it possible to independently adjust the position (distance from the optical axis BX) of a region with a large amount of light in two directions orthogonal to each other.

  However, in FIG. 1A, the first prism 71 and the second prism 72 are omitted when it is not necessary to change the positions of a plurality of regions having a large amount of light on the pupil plane Q1 of the illumination optical system 12 in the radial direction. It is also possible to do. The fly-eye lens 5 includes, for example, a bundle of a large number of lens elements having a rectangular cross-sectional shape with a width and width of about several millimeters, as well as a quadrangle with a cross-sectional shape of about several tens of μm or a diameter of several tens of μm. It is also possible to use a micro fly's eye lens having a configuration in which a large number of micro lenses having a circular shape are bundled.

  The illumination light IL composed of the light beam emitted from the fly-eye lens 5 is once condensed on the surface Q2 by the condenser lens system 6. A fixed field stop (fixed blind) 7 for defining an illumination area on the reticle R as an object to be illuminated in an elongated shape in a non-scanning direction orthogonal to the scanning direction is disposed slightly on the front side of the surface Q2. A movable field stop (movable blind) 8 is disposed on Q2. The movable field stop 8 is used to control the width in the scanning direction of the illumination area before and after scanning exposure to prevent unnecessary exposure and to define the width in the non-scanning direction of the illumination area during scanning exposure. Is done. As an example, a reticle stage drive system 16 to be described later controls the opening / closing operation of the movable field stop 8 via the drive unit 13 in synchronization with the operation of the reticle stage 14.

  The illumination light IL that has passed through the field stops 7 and 8 passes through the imaging lens system 9, the optical path bending mirror 10, and the main condenser lens system 11 to form a pattern surface of the reticle R (hereinafter referred to as a reticle surface). An illumination area defined in a slit shape (rectangular shape in this example) on the circuit pattern area is illuminated with a uniform intensity distribution. A beam expander 2, a mirror 3, a diffractive optical element 21, etc., a relay lens 4, prisms 71 and 72, a fly-eye lens 5, a condenser lens system 6, a field stop 7, 8, an imaging lens system 9, a mirror 10, and An illumination optical system 12 having an optical axis BX is configured including the main condenser lens system 11. In this case, the exit surface of the fly-eye lens 5 coincides with the pupil plane Q1 of the illumination optical system 12, that is, the optical Fourier transform plane with respect to the reticle plane, and the plane Q2 on which the movable field stop 8 is disposed. Is the conjugate plane of the reticle plane. Note that the fixed field stop 7 may be disposed in the vicinity of the reticle surface, for example.

  The illumination optical system 12 includes a drive unit 74 and a polarization state setting plate 73 in order to further improve the resolution of the transferred pattern, and polarization control that controls the polarization state of the illumination light IL on the pupil plane Q1. A system may be provided. The main control system 17 places the polarization state setting plate 73 on the optical path of the illumination light IL in the vicinity of the pupil plane Q1 via the drive unit 74, so that the polarization state of the illumination light IL is set to a desired state.

  Under the illumination light IL, an image of a predetermined circuit pattern in the illumination area of the reticle R is projected at a projection magnification β (β is, for example, 1/4, 1/5, etc.) via the bilateral telecentric projection optical system PL. Then, the image is transferred to the photoresist layer of one shot region among the plurality of shot regions on the wafer W arranged on the imaging plane of the projection optical system PL. The wafer W is a disk-shaped substrate having a diameter of 200 mm or 300 mm, such as a semiconductor (silicon or the like) or SOI (silicon on insulator).

  The optical axis AX of the projection optical system PL coincides with the optical axis BX of the illumination optical system 12 on the reticle R. The pupil plane Q3 (optical Fourier transform plane with respect to the reticle plane) of the projection optical system PL is conjugate with the pupil plane Q1 of the illumination optical system 12, and an aperture stop AS is provided in the vicinity of the pupil plane Q3. . As the projection optical system PL of this example, in addition to the refractive system, a catadioptric projection optical system having a plurality of optical systems having optical axes intersecting each other as disclosed in, for example, Japanese Patent Application Laid-Open No. 2000-47114. Or an optical system having an optical axis from the reticle to the wafer and a catadioptric system having an optical axis substantially perpendicular to the optical axis, as disclosed in, for example, International Publication (WO) 01/065296 And a catadioptric projection optical system that forms an intermediate image twice inside can be used. Furthermore, as disclosed in, for example, International Publication (WO) 2004/107011, an optical system (a reflective system or a reflex system) having a plurality of reflective surfaces and forming an intermediate image at least once is one of them. A so-called in-line catadioptric projection optical system that is provided in the unit and has a single optical axis can also be used.

  Next, the reticle R is sucked and held on the reticle stage 14 so that the reticle surface is arranged on the object surface (first surface) of the projection optical system PL parallel to the XY plane. The reticle stage 14 is a reticle base. 15 can be moved at a constant speed in the Y direction, and can be finely moved at least in the X direction, the Y direction, and the rotation direction around the Z axis. The position (including the rotation angle) of reticle stage 14 is measured by a laser interferometer in reticle stage drive system 16. The reticle stage drive system 16 controls the position and speed of the reticle stage 14 via a drive mechanism (not shown) based on the measurement information and the control information from the main control system 17. A reticle stage system is configured including the reticle stage 14, the reticle base 15, and a driving mechanism thereof.

  On the other hand, the wafer W is placed on the wafer stage 18 via a wafer holder (not shown) so that the surface (exposure surface) thereof is disposed on the imaging surface (second surface) of the projection optical system PL parallel to the XY plane. The wafer stage 18 is sucked and held, and is placed on the wafer base 19 so as to be movable in the X and Y directions. The position of the wafer stage 18 (including the rotation angle) is measured by a laser interferometer in the wafer stage drive system 20. The wafer stage drive system 20 controls the position and speed of the wafer stage 18 via a drive mechanism (not shown) based on the measurement information and the control information from the main control system 17. Further, the wafer stage 18 has a wafer W 18 in the projection area (irradiation area of the illumination light IL conjugate to the illumination area with respect to the projection optical system PL) during scanning exposure based on measurement information of an autofocus sensor (not shown). A focusing mechanism for aligning the surface with the imaging plane of the projection optical system PL is incorporated. A wafer stage system is configured including the wafer stage 18, the wafer base 19, and a driving mechanism thereof.

  During scanning exposure, under the control of the main control system 17, the reticle stage drive system 16, and the wafer stage drive system 20, the reticle R is scanned in the Y direction with respect to the illumination area at a speed VR through the reticle stage. In synchronism with this, an operation of scanning one shot area on the wafer W with respect to the projection area through the wafer stage 18 in a corresponding direction at a speed β · VR (β is the projection magnification), and the illumination light IL The operation of stopping the irradiation and moving the wafer W stepwise in the X direction and / or the Y direction via the wafer stage 18 is repeated. By this step-and-scan operation, the image of the circuit pattern of the reticle R is transferred to all shot areas on the wafer W.

Next, the illumination optical system and exposure method of the exposure apparatus of this example will be described in detail.
FIG. 2 is an enlarged view showing a transfer pattern 31X having periodicity in the X direction formed on the reticle R in FIG. This pattern 31X is used when forming a circuit pattern of a predetermined layer, for example, in the manufacturing process of SRAM (Static Random Access Memory). For convenience of explanation, in FIG. 2 (the same applies to FIG. 6 described later), the light shielding portion is represented by a white portion and the light transmitting portion is represented by a black portion. However, the same imaging characteristics can be obtained even with a pattern in which the light shielding portion and the light transmitting portion are reversed.

  In FIG. 2, the pattern 31X includes line-and-space patterns (hereinafter referred to as L & S patterns) 32XA and 32XB formed at a predetermined period (pitch) P1 at two locations separated in the X direction, and these L & S. Between the patterns 32XA and 32XB, a line pattern row 34X formed in the X direction with a period P2 larger than the period P1 is provided. The former L & S patterns 32XA and 32XB are formed by forming a large number of rectangular light-transmitting portions 33 elongated in the Y direction having a width of about P1 / 2 in the X direction with a period P1 with the light shielding portion as a background. . In FIG. 2, the number of the light transmitting portions 33 in the L & S patterns 32XA and 32XB is four, but actually the number of the light transmitting portions 33 is considerably larger than four (for example, 32). The latter line pattern row 34X has two light transmission parts (line patterns) 35 elongated in the Y direction in the X direction, with the width D2 in the X direction being about 1/3 to 2/3 of the period P2, with the light shielding part as the background. And a cycle (here, the interval between the centers of two adjacent identical patterns) P2. Further, the interval S1 between the line pattern row 34X and the L & S patterns 32XA and 32XB is approximately the period P1. Note that. The interval between the line pattern row 34X and the L & S patterns 32XA and 32XB may be different from each other.

  The dimensions of each part of the pattern 31X are, for example, at the stage of a projected image on the wafer. For example, the period P1 is 120 nm or less, the period P2 is about 300 to 700 nm, and the interval S1 is 1/2 to several times the period P1. Yes, the length in the Y direction is several μm or less. Note that the L & S patterns 32XA and 32XB only need to include at least two light transmission portions 33, and the line pattern row 34X only needs to include at least two light transmission portions 35. Further, the L & S patterns 32XA and 32XB are not necessarily the same (symmetric) pattern, and one of the L & S patterns 32XA and 32XB may be omitted.

  Next, when the pattern 31X in FIG. 2 is projected onto the wafer W via the projection optical system PL in FIG. 1A, the main control system 17 in FIG. 1A passes through the light quantity distribution setting system. Then, the light quantity distribution on the pupil plane Q1 of the illumination optical system 12 is set as shown in FIG. 3A shows a light amount distribution on the pupil plane Q1 of the illumination optical system 12, and FIG. 3B shows a light amount distribution of diffracted light (imaging light beam) on the pupil plane Q3 of the projection optical system PL. ), The circumference around the optical axis BX where the coherence factor (σ value) is maximum (= 1) is defined as the maximum σ portion 40 in the X direction and the Y direction on the reticle R in FIG. The corresponding directions are the X direction and the Y direction, respectively. In this case, since the pupil plane Q1 and the pupil plane Q3 are conjugate, the zero-order light from the reticle R by the illumination light that has passed through the maximum σ portion 40 is the pupil of the projection optical system PL in FIG. In the surface Q3, it passes through the inside of the maximum numerical aperture portion 50 (circumference centered on the optical axis AX) where the numerical aperture defined by the aperture stop AS is maximized and reaches the wafer W.

  In FIG. 3A, the amount of illumination light is symmetrically separated in the X direction (the direction corresponding to the periodic direction of the L & S patterns 32XA and 32XB in FIG. 2) with respect to the optical axis BX, and substantially within the maximum σ portion 40. A pair of elliptical areas 41A and 41B elongated in the Y direction and arranged in contact with each other, and the maximum σ portion 40, the optical axis BX and the Y direction (perpendicular to the periodic direction of the line pattern row 34X in FIG. 2) The amount of light in the pair of circular regions 42A and 42B arranged symmetrically apart in the direction corresponding to the direction) is set to be larger than the amount of light in the other regions. As an example, the amount of illumination light is set to be approximately a predetermined constant value in the regions 41A and 41B and the regions 42A and 42B, and is substantially 0 in the other regions.

  More practically, the light amount distribution obtained by the diffractive optical element 21 in FIG. 1A is almost constant in the region including the four regions 41A, 41B, 42A, and 42B in FIG. The aperture stop in which openings are formed in portions corresponding to the four regions 41A to 42B is used as the exit surface (pupil surface Q1) of the fly-eye lens 5 in FIG. You may arrange | position to a conjugate surface or the surface of those vicinity. Also in this case, the advantage that the utilization efficiency of the illumination light IL is high is obtained. The regions 41A and 41B need only be substantially symmetric in the X direction with respect to the optical axis BX, and the regions 42A and 42B may be substantially symmetric in the Y direction with respect to the optical axis BX.

  3A, the radius of the maximum σ portion 40 is ra, the distance between the centers of the regions 41A and 41B in the X direction is 2 × rb, the center of the region 42B (the region 42A is the same), and the optical axis BX. Let the interval in the Y direction be δa. Hereinafter, the distance on the pupil plane Q1 in FIG. 3A and the pupil plane Q3 in FIG. 3B is expressed in units of the numerical aperture on the reticle R of the illumination light. In this case, on the pupil plane Q3 of the projection optical system PL in FIG. 3B, the radius of the maximum numerical aperture 50 is ra, and the zero-order light of the illumination light that has passed through the regions 41A and 41B in FIG. The distance in the X direction is 2 · rb, and the distance in the Y direction from the optical axis AX of the zero-order light of the illumination light that has passed through the regions 42A and 42B is δa. Further, the wavelength of the illumination light IL is λ, and the period on the wafer of the finest L & S pattern projected satisfactorily through the projection optical system PL under normal incidence and deformation illumination (tilted illumination) is defined as Pmin ′. And Pmin, Pmin = Pmin ′ / 2, and the radius ra is as follows.

ra = λ / Pmin ′ = λ / (2 · Pmin) (1)
The radius rb that defines the distance 2 · rb in the X direction between the centers of the regions 41A and 41B is set slightly smaller than the radius ra. Assuming that a possible minimum value of the period P1 of the L & S patterns 32XA and 32XB in the pattern 31X of FIG. 2 is P1min (> Pmin), the radius rb is set as follows as an example. Hereinafter, it is assumed that the period P1 is the minimum value P1min.

rb = λ / (2 · P1min) (2)
Regarding the range of the interval δa from the optical axis BX of the regions 42A and 42B, the second-order or higher-order diffracted light from the line pattern row 34X in FIG. 2 by the illumination light IL that has passed through the regions 42A and 42B is the maximum of the projection optical system PL. It is set so as not to pass through the inside of the numerical aperture 50. Hereinafter, the range of the interval δa will be described.

  When the pattern 31X of FIG. 2 is illuminated with the illumination light of the light quantity distribution of FIG. 3A, the light quantity distribution on the pupil plane Q3 of the projection optical system PL of the diffracted light (imaging light beam) from this pattern 31X is as shown in FIG. As shown in (B). In the region within the maximum numerical aperture portion 50 in FIG. 3B, the 0th-order light L1A and the −1st-order diffracted light L1B from the L & S patterns 32XA and 32XB in FIG. 2 by the illumination light that has passed through the region 41A in FIG. 2 passes through the region corresponding to the regions 41B and 41A, and the 0th-order light L2A and the + 1st-order diffracted light L2B from the L & S patterns 32XA and 32XB in FIG. 2 by the illumination light that has passed through the region 41B in FIG. It passes through the area corresponding to 41A and 41B. That is, the 0th order light and the ± 1st order diffracted light are generated symmetrically in the X direction from the L & S patterns 32XA and 32XB by the illumination light that has passed through the regions 41B and 41A. When the period P1 of the L & S patterns 32XA and 32XB is larger than the minimum value P1min, the 0th-order light and the ± 1st-order diffracted light are generated from the L & S patterns 32XA and 32XB with substantially symmetrical inclination in the X direction.

  Further, in the region within the maximum numerical aperture 50 of FIG. 3B, the zero-order light L3A from the line pattern row 34X (period P2) of FIG. 2 by the illumination light that has passed through the region 42A of FIG. The ± 1st-order diffracted beams L3B and L3C pass through a region corresponding to the region 42B and a region separated from this region by λ / P2 in the ± X direction. Then, the 0th-order light L4A and the ± 1st-order diffracted lights L4B and L4C from the line pattern array 34X in FIG. 2 by the illumination light that has passed through the region 42B in FIG. 3A are the region corresponding to the region 42A, and from this region. It passes through a region separated by λ / P2 in the ± X direction. Further, the ± 2nd order diffracted lights L3D, L3E and L4D, L4E from the line pattern row 34X (period P2) in FIG. 2 by the illumination light that has passed through the regions 42A, 42B in FIG. The diffracted light is shielded by the aperture stop AS.

In this case, in FIG. 3B, since the radius of the maximum numerical aperture 50 is ra, if the distance between the optical axis AX and the centers of the + 1st order diffracted light L4B and + 2nd order diffracted light L4D is rc and rd, respectively, The relationship is established.
rc <ra <rd (3)
Further, the distance in the Y direction between the optical axis AX and the center of the 0th order light L4A is δa, the distance in the X direction between the 0th order light L4A and the + 1st order diffracted light L4B is λ / P2, and the + 2nd order from the + 1st order diffracted light L4B. Since the center distance in the X direction with respect to the folded light L4D is λ / P2, the distances rc and rd can be expressed as follows.

rc = {δa ² + (λ / P2) ² } ^1/2 (4A)
rd = {δa ² + (2λ / P2) ² } ^1/2 (4B)
By substituting these equations (4A) and (4B) into equation (3), the range of the interval δa can be obtained.
Further, on the wafer W in FIG. 1A, among the diffracted light (imaging light beam) passing through the aperture stop AS of the projection optical system PL in FIG. 3B, the 0th-order light L1A, L2A and 1 The L & S patterns 32XA and 32XB in FIG. 2 are formed by the next-order diffracted lights L1B and L2B, and the image of the line pattern row 34X in FIG. 2 is formed by the 0th-order lights L3A and L4A and the first-order diffracted lights L3B, L3C, L4B, and L4C. The At this time, the L & S patterns 32XA and 32XB, which are close-packed patterns close to the resolution limit, are illuminated with modified illumination (tilted illumination) that uses the numerical aperture of the projection optical system PL almost to the limit. It is well formed with high resolution and deep depth of focus. On the other hand, with respect to the line pattern row 34X which is a coarser pattern, the numerical aperture of the projection optical system PL is substantially limited as shown in FIG. Does not contribute. Therefore, the image of the line pattern row 34X has less intensity fluctuation when defocused, and is formed well at a deep focal depth. Thereafter, by developing the photoresist on the wafer W, a resist pattern corresponding to the pattern 31X in FIG. 2 is formed in each shot region on the wafer W, and etching or the like is performed using this resist pattern as a mask. A pattern is formed.

Thus, according to this example, since the light quantity distribution on the pupil plane Q1 of the illumination optical system 12 is set as shown in FIG. 3A, the L & S patterns 32XA and 32XB and the lines having two different periods in FIG. An image of the pattern row 34X can be formed on the wafer W at the same time. Therefore, devices having various periods or intervals can be efficiently manufactured.
In order to further increase the resolution of the image of the pattern 31X in FIG. 2, the polarization state setting plate 73 in FIG. 1A is arranged in the vicinity of the pupil plane Q1, and the regions 41A, 41B, The illumination light IL passing through 42A and 42B may be set to linearly polarized light in the Y direction. This is because the pattern 31X to be transferred is composed of a plurality of patterns elongated in the Y direction.

  Next, in the above embodiment, the secondary light source for illuminating the line pattern row 34X in FIG. 2 has the optical axis BX on the pupil plane Q1 of the illumination optical system 12, as shown in FIG. Two regions 42A and 42B arranged so as to be sandwiched in the Y direction are set. Instead, as shown by another light quantity distribution on the pupil plane Q1 of the illumination optical system 12 in FIG. 4A, a straight line passing through the optical axis BX and parallel to the Y direction through one region 42A in FIG. 3A is divided into two regions 43A and 43B, and the other region 42B in FIG. 3A is divided into two regions 44A and 44B symmetrical with respect to a straight line passing through the optical axis BX and parallel to the Y direction. , 43B, 44A, 44B, the line pattern row 34X in FIG. 2 may be illuminated with illumination light.

  4A, regions 41A and 41B as secondary light sources for illuminating the L & S patterns 32XA and 32XB in FIG. 2 are the same as those in FIG. 3A, and the L & S patterns 32XA and 32XB are the same as those in FIG. Imaging is performed in the same manner as in the case of using the light amount distribution of A). Further, when the wavelength λ of the illumination light and the period P2 in the X direction of the line pattern row 34X in FIG. 2 are used, the interval δc in the X direction between the two regions 43A, 43B and 44A, 44B is common with the numerical aperture as a unit. Is set to λ / P2. Also, the interval δb in the Y direction from the optical axis BX of the two regions 43A, 43B and 44A, 44B is 2 from the line pattern row 34X in FIG. 2 by the illumination light that has passed through the regions 43A, 43B and the regions 44A, 44B. It is set so that the next or higher diffracted light is shielded by the aperture stop AS of the projection optical system PL.

  When the pattern 31X shown in FIG. 2 is illuminated with the illumination light having the light quantity distribution shown in FIG. 4A, the light quantity distribution on the pupil plane Q3 of the projection optical system PL of the diffracted light (imaging light beam) from the pattern 31X is shown in FIG. As shown in (B). In the region within the maximum numerical aperture portion 50 of FIG. 4B, the zero-order light L5A from the line pattern row 34X of FIG. 2 and the illumination light that has passed through the regions 43A and 43B in the −Y direction of FIG. L6A passes through regions corresponding to the regions 44B and 44A, and the −1st order diffracted light L5C and the + 1st order diffracted light L6B from the line pattern row 34X by the illumination light pass through regions corresponding to the regions 44A and 44B.

  Similarly, the 0th-order lights L7A and L8A from the line pattern row 34X in FIG. 2 by the illumination light that has passed through the + Y-direction regions 44A and 44B in FIG. 4A pass through the regions corresponding to the regions 43B and 43A. The −1st order diffracted light L7C and the + 1st order diffracted light L8B from the line pattern row 34X by the illumination light pass through regions corresponding to the regions 43A and 43B. That is, the illumination light that has passed through the regions 43A, 43B and 44A, 44B generates 0th-order light and ± 1st-order diffracted light that are symmetrically inclined in the X direction from the line pattern array 34X. Further, the ± first-order diffracted light L5B, L6C, -second-order diffracted light L5E, + second-order diffracted light L6D from the line pattern array 34X in FIG. 2 by the illumination light that has passed through the regions 43A and 43B in FIG. The first-order diffracted light L7B, L8C, -2nd-order diffracted light L7E, + 2nd-order diffracted light L8D, and higher-order diffracted light from the line pattern array 34X by the illumination light that has passed through the regions 44A, 44B of A) Light is shielded by the stop AS. Note that the period P2 of the line pattern row 34X may be somewhat different from λ / δc (δc = λ / P2). In this case, the line pattern row 34X includes zero-order light and ± first-order diffracted light. Are generated in a substantially symmetrical manner in the X direction.

In this case, since the radius of the maximum numerical aperture 50 is ra in FIG. 4B, the center of the optical axis AX and the 0th order light L7A (+ 1st order diffracted light L8B) and + 1st order diffracted light L7B (+ 2nd order diffracted light L8D). The following relations are established, where re and rf are the intervals of
re <ra <rf (5)
The interval in the Y direction between the optical axis AX and the center of the 0th order light L7A is δb, and the interval between the 0th order light L7A and the straight line passing through the optical axis AX and parallel to the Y direction is λ / (2 · P2), 0. Since the center distance in the X direction between the next light L7A and the + 1st order diffracted light L7B is λ / P2, the distances re and rf can be expressed as follows.

re = {δb ² + (λ / (2 · P2)) ² } ^1/2 (6A)
rf = {δb ² + (3λ / (2 · P2)) ² } ^1/2 (6B)
By substituting these equations (6A) and (6B) into equation (5), the range of the interval δb can be obtained.
Similar to the case of using the light amount distribution of FIG. 3A, the diffracted light (imaging light beam) passing through the aperture stop AS of the projection optical system PL of FIG. 4B on the wafer W of FIG. 2), the image of the line pattern row 34X in FIG. 2 is formed by the 0th-order light L5A, L6A, L7A, L8A and the first-order diffracted light L5C, L6B, L7C, L8B. At this time, as shown in FIG. 4B, the numerical aperture of the projection optical system PL is substantially limited, and the line pattern row 34X is generated almost symmetrically with the 0th order light and the 0th order light. Diffracted light other than the first-order diffracted light does not contribute to image formation. Therefore, the image of the line pattern row 34X has less intensity fluctuation when defocused, and is formed well at a deep focal depth. As described above, the image formation characteristic can be further improved by performing the modified illumination on the line pattern row 34X.

  Next, FIG. 5 uses the light amount distribution of FIG. 3 (A) while gradually changing the exposure amount (dose) and the defocus amount using the exposure apparatus of FIG. 1 (A). When the pattern 31X is projected onto the photoresist layer on the wafer W via the projection optical system PL, the exposure amount error DE (%) and the depth of focus (DOF) for keeping the line width of the formed image within an allowable range. ) (Nm) shows an example of a result obtained by computer simulation. The simulation conditions of FIG. 5 are as follows: the period P1 of the L & S pattern 32XA of FIG. 2 is 100 nm, the width D2 of the light transmission part 35 of the line pattern row 34X is 150 nm, the period P2 is 400 nm, and the interval S1 is 100 nm. The drawing error of the pattern 31X was set to ± 1 nm. Further, assuming that the numerical aperture NA on the wafer W side of the projection optical system PL in FIG. 1A is 1 (immersion exposure), the σ value outside the areas 41A and 41B in FIG. The σ value was 0.92.

From the result of FIG. 5, it can be seen that two patterns with periods of 100 nm and 400 nm can be projected on the wafer with a deep focal depth of about 260 nm even when the exposure dose error is 5%.
Next, a second embodiment of the present invention will be described with reference to FIGS. In this example as well, the exposure apparatus of FIG. 1A is used, but since the pattern to be transferred is different, the light amount distribution on the pupil plane Q1 of the illumination optical system 12 is also different accordingly.

  FIG. 6 is an enlarged view showing a pattern to be exposed formed on the reticle R of this example. In FIG. 6, the pattern is a pattern 31X having periodicity in the X direction as in the example of FIG. And a pattern 31Y having a periodicity in the Y direction obtained by rotating the pattern 31X by 90 °. That is, the pattern 31Y includes L & S patterns 32YA and 32YB formed with a period P1 in the Y direction, and a line pattern row 34Y formed with a period P2 in the Y direction therebetween.

  Thus, since the pattern to be transferred in FIG. 6 in this example has periodicity in the X direction and the Y direction, the pattern in FIG. 6 is applied onto the wafer W via the projection optical system PL in FIG. When projecting, the main control system 17 in FIG. 1A sets the light quantity distribution on the pupil plane Q1 of the illumination optical system 12 as shown in FIG. 7 via the light quantity distribution setting system. In FIG. 7 in which parts corresponding to FIG. 3A are assigned the same reference numerals, the amount of illumination light is symmetrical in the X direction (the direction corresponding to the periodic direction of the pattern 31X in FIG. 6) with respect to the optical axis BX. A pair of elliptical regions 41A and 41B elongated in the Y direction and arranged so as to be substantially inscribed in the maximum σ portion 40, and the regions 41A and 41B within the maximum σ portion 40 are separated from the optical axis BX. The amount of light in the pair of X-direction elongated regions 45A and 45B obtained by rotating 90 ° around is set so as to be larger than the amount of light in the other regions. As an example, the amount of illumination light is set to be substantially a predetermined constant value in the areas 41A, 41B, 45A, and 45B, and to be almost 0 in other areas.

  In FIG. 7, the radius of the maximum σ portion 40 is ra, the distance between the centers of the regions 41A and 41B (regions 45A and 45B) in the X direction (Y direction) is 2 × rb, and the regions 41A and 41B (regions 45A and 45B). ) In the Y direction (X direction). In this case, when the expected minimum value of the period of the rough line pattern rows 34X and 34Y in FIG. 6 is P2min and the wavelength λ of the illumination light is used, the length δd is set as follows with the numerical aperture as a unit. Is done. Accordingly, the radius rb is set so that the expression (7) is substantially satisfied.

δd = λ / P2min (7)
As a result, the illumination light from the regions 45A and 45B in FIG. 7 is illuminated from the regions 43A, 43B, 44A, and 44B in FIG. 4A with respect to the line pattern row 34X in the pattern 31X in the X direction in FIG. Acts like light. The illumination light from the areas 41A and 41B in FIG. 7 rotates the areas 43A, 43B, 44A, and 44B in FIG. 4A by 90 ° with respect to the line pattern row 34Y in the pattern 31Y in the Y direction in FIG. It acts in the same way as the illumination light from the area.

  Accordingly, when the patterns 31X and 31Y in FIG. 6 are illuminated with the illumination light having the light amount distribution in FIG. 7, the L & S patterns 32XA and 32XB in the pattern 31X in FIG. 6 are illuminated by the illumination light from the regions 41A and 41B in the X direction in FIG. And the image of the line pattern row 34Y in the pattern 31Y is formed with a high resolution and a deep depth of focus via the projection optical system PL. Similarly, the image of the line pattern row 34X in the pattern 31X in FIG. 6 and the L & S patterns 32YA and 32YB in the pattern 31Y are high via the projection optical system PL by the illumination light from the regions 45A and 45B in the Y direction in FIG. It is formed with a resolution and a deep depth of focus.

  In other words, the L & S patterns 32XA, 32XB and 32YA, 32YB, which are dense patterns close to the resolution limit, are illuminated with modified illumination (tilted illumination) using the numerical aperture of the projection optical system PL to the limit. The image is well formed with high resolution and deep depth of focus. On the other hand, with respect to the line pattern rows 34X and 34Y, which are coarser than that, the numerical aperture of the projection optical system PL is substantially limited, and the intensity variation when defocused is small, and the depth of focus is good. Formed. Accordingly, the images of the patterns 31X and 31Y having periodicity in two orthogonal directions in FIG. 6 and two patterns having different periods (L & S patterns 32XA and 32YA and line pattern rows 34X and 34Y) can be obtained simultaneously with the wafer. It can be formed on W. Therefore, devices having various periods or intervals can be efficiently manufactured.

  In FIG. 1A, the fly-eye lens 5 is used as an optical integrator, but an internal reflection type integrator or a diffractive optical element may be used as the optical integrator. In the internal reflection type integrator, the light intensity distribution (size and shape of the secondary light source) of the illumination light on the pupil plane of the illumination optical system can be controlled by changing the incident angle range of the illumination light incident thereon.

  Further, when a semiconductor device such as SRAM is manufactured using the projection exposure apparatus of the above-described embodiment, the semiconductor device includes a step of designing a function / performance of the device, a step of manufacturing a reticle based on this step, silicon A step of forming a wafer from the material, a step of performing alignment with the exposure apparatus of the above-described embodiment to expose the pattern of the reticle onto the substrate (wafer), a step of developing the exposed substrate, heating (curing) of the developed substrate, and It is manufactured through a substrate processing step including an etching process, a device assembly step (including a dicing process, a bonding process, and a package process), an inspection step, and the like.

  In addition, the illumination optical system and projection optical system composed of a plurality of lenses are incorporated into the exposure apparatus main body for optical adjustment, and a reticle stage and wafer stage consisting of a large number of mechanical parts are attached to the exposure apparatus main body for wiring and piping. The exposure apparatus of the above-described embodiment can be manufactured by connecting and further performing general adjustment (electric adjustment, operation check, etc.). The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  The present invention can be applied not only to a scanning exposure type projection exposure apparatus but also to exposure using a batch exposure type (stepper type) projection exposure apparatus. The present invention can also be applied to exposure using an immersion type exposure apparatus disclosed in, for example, International Publication No. 99/49504 and International Publication No. 2004/019128. In this case, during scanning exposure, a liquid such as pure water is locally supplied between the projection optical system PL and the wafer W from a liquid recovery apparatus (not shown) in FIG. Is recovered by a liquid recovery device (not shown).

  Further, as disclosed in, for example, Japanese translations of PCT publication No. 2004-51850 (and corresponding US Pat. No. 6,611,316), two reticle patterns are synthesized on a substrate via a projection optical system. The present invention can also be applied to an exposure apparatus that performs double exposure of one shot area on a substrate almost simultaneously by one scanning exposure. Furthermore, the present invention can also be applied to the case where exposure is performed with a projection exposure apparatus that uses extreme ultraviolet light (EUV light) having a wavelength of about several nm to 100 nm as an exposure beam. When EUV light is used, the mask is a reflection type, and an illumination system composed of a reflective optical member is used for illuminating the mask pattern, and a projection system composed of a reflective optical member is used to project the pattern. .

  In the above-described embodiment, a mask (reticle) on which a transfer pattern is formed is used. Instead of this mask, for example, as disclosed in US Pat. No. 6,778,257. An electronic mask that forms a transmission pattern or a reflection pattern based on electronic data of a pattern to be exposed may be used. This electronic mask is also called a variable shaping mask, and includes, for example, a DMD (Digital Micro-mirror Device) which is a kind of non-light emitting image display element (spatial light modulator).

  In addition, the present invention is not limited to application to a semiconductor device manufacturing process. For example, a manufacturing process of a display device such as a liquid crystal display element or a plasma display formed on a square glass plate, or an imaging element (CCD, etc.), micromachines, MEMS (Microelectromechanical Systems), thin film magnetic heads, and various devices such as DNA chips can be widely applied. Furthermore, the present invention can also be applied to a manufacturing process when manufacturing a mask (photomask, reticle, etc.) on which mask patterns of various devices are formed using a photolithography process.

  In addition, this invention is not limited to the above-mentioned embodiment, Of course, a various structure can be taken in the range which does not deviate from the summary of this invention.

  According to the device manufacturing method of the present invention, in the exposure step, two patterns having different periods or intervals can be satisfactorily transferred onto the substrate by one exposure, and therefore, a plurality of patterns arranged at various periods or intervals can be obtained. The device you have can be manufactured with high precision and efficiency.

(A) is a diagram showing the configuration of the exposure apparatus of the first embodiment, (B) is an enlarged perspective view showing the prisms 71 and 72 in FIG. 1 (A), and (C) is another diagram of the prisms 71 and 72. It is a figure which shows the example of a structure. It is an enlarged view showing a pattern for transfer according to the first embodiment. (A) is a figure which shows an example of the light quantity distribution on the pupil plane of an illumination optical system, (B) is the diffracted light formed on the pupil plane of a projection optical system corresponding to the light quantity distribution of FIG. 3 (A). It is a figure which shows light quantity distribution of (imaging light beam). (A) is a figure which shows the other example of the light quantity distribution on the pupil plane of an illumination optical system, (B) is formed on the pupil plane of a projection optical system corresponding to the light quantity distribution of FIG. 4 (A). It is a figure which shows light quantity distribution of diffracted light (imaging light beam). It is a figure which shows the relationship between the tolerance | permissible_range of the exposure amount error in the case of using the light quantity distribution of FIG. It is an enlarged view showing a pattern for transfer according to a second embodiment. It is a figure which shows an example of light quantity distribution on the pupil surface of the illumination optical system of 2nd Embodiment.

Explanation of symbols

  R ... reticle, PL ... projection optical system, W ... wafer, Q1 ... pupil plane of illumination optical system, Q3 ... pupil plane of projection optical system, 5 ... fly-eye lens, 12 ... illumination optical system, 21 ... diffractive optical element, 31X, 31Y ... patterns for transfer, 32XA, 32XB ... L & S pattern, 34X ... line pattern row, 40 ... maximum sigma portion, 41A, 41B ... elliptical region, 42A, 42B ... circular region, 50 ... maximum numerical aperture Part, L1A to L4A ... 0th order light, L1B to L4B, L3C, L4C ... 1st order diffracted light, 73 ... polarization state setting plate

Claims (11)

In an exposure method of illuminating a pattern with a light beam from an illumination system and exposing the substrate with the light beam through the pattern and the projection system,
The pattern includes a first pattern periodically formed in a first direction and a second pattern formed in the first direction with a period longer than the period of the first pattern,
The projection system is provided with an aperture stop through which the second-order diffracted light generated from the second pattern can pass when a light beam from the illumination system is incident on the second pattern substantially perpendicularly.
A light amount distribution of the light flux on a predetermined surface related to the illumination system,
First and second regions arranged substantially symmetrically apart in a direction corresponding to the first direction with respect to the optical axis of the illumination system, and a direction corresponding to a second direction orthogonal to the first direction with respect to the optical axis Are set so that the amount of light in the four regions composed of the third and fourth regions arranged substantially symmetrically apart from each other is larger than the amount of light in the other regions ,
The position of the third and fourth regions is determined by diffracting light of at least one of ± first-order diffracted light among zero-order light and diffracted light generated from the second pattern by light beams from the third and fourth regions. And an exposure method characterized by setting so that second-order or higher-order diffracted light does not pass through the projection system . The predetermined plane is a pupil plane of the illumination system or a conjugate plane thereof,
An interval in a direction corresponding to the first direction of the first and second regions is set according to a period of the first pattern,
2. The exposure method according to claim 1, wherein an interval between the third and fourth regions in a direction corresponding to the second direction is set according to a period of the second pattern. The first and second regions are set so that zero-order light and first-order diffracted light are substantially symmetrically generated from the first pattern by light beams from the first and second regions. 2. The exposure method according to 2. The third and fourth regions each include two partial regions disposed symmetrically with respect to a straight line that passes through the optical axis and is parallel to a direction corresponding to the second direction,
4. The exposure method according to claim 1, wherein each of the first and second regions is an elliptical region elongated in a direction corresponding to the second direction. 5. The positions of the two partial regions of the third region and the two partial regions of the fourth region are such that one of the ± first-order diffracted light generated from the second pattern by the light flux from the four partial regions is also diffracted light. The exposure method according to claim 4, wherein the exposure method is set so as not to pass through the projection system. In an exposure apparatus that illuminates a pattern with a light beam from an illumination system and exposes the substrate with the light beam through the pattern and the projection system,
A light amount distribution setting mechanism for setting a light amount distribution of the luminous flux on a predetermined surface related to the illumination system;
A control device for controlling the light amount distribution setting mechanism according to the pattern,
The pattern includes a first pattern periodically formed in a first direction, and a second pattern formed in the first direction with a period longer than the period of the first pattern,
When the projection system is provided with an aperture stop through which the second-order diffracted light generated from the second pattern can pass when the light beam from the illumination system is incident on the second pattern substantially perpendicularly ,
The control device controls the light amount distribution setting mechanism to change the light amount distribution of the light flux on the predetermined surface,
First and second regions arranged substantially symmetrically apart in a direction corresponding to the first direction with respect to the optical axis of the illumination system, and a direction corresponding to a second direction orthogonal to the first direction with respect to the optical axis And the amount of light in the four regions consisting of the third and fourth regions disposed substantially symmetrically apart from each other is set to be larger than the amount of light in the other regions ,
The position of the third and fourth regions is determined by diffracting light of at least one of ± first-order diffracted light among zero-order light and diffracted light generated from the second pattern by light beams from the third and fourth regions. And an exposure apparatus characterized in that the second-order or higher-order diffracted light does not pass through the projection system . The predetermined plane is a pupil plane of the illumination system or a conjugate plane thereof,
An interval in a direction corresponding to the first direction of the first and second regions is set according to a period of the first pattern,
The exposure apparatus according to claim 6, wherein an interval between the third and fourth regions in a direction corresponding to the second direction is set according to a period of the second pattern. The first and second regions are set so that zero-order light and first-order diffracted light are substantially symmetrically generated from the first pattern by light beams from the first and second regions. 8. The exposure apparatus according to 7. The third and fourth regions each include two partial regions disposed symmetrically with respect to a straight line that passes through the optical axis and is parallel to a direction corresponding to the second direction,
9. The exposure apparatus according to claim 6, wherein each of the first and second regions is an elliptical region that is elongated in a direction corresponding to the second direction. 10. The positions of the two partial regions of the third region and the two partial regions of the fourth region are such that one of the ± first-order diffracted light generated from the second pattern by the light flux from the four partial regions is also diffracted light. The exposure apparatus according to claim 9, wherein the exposure apparatus is set so as not to pass through the projection system. A device manufacturing method including a lithography process,
A device manufacturing method, wherein a pattern is transferred to a photoreceptor using the exposure method according to claim 1 in the lithography process.

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