JP2010192562A - Surface position detecting apparatus and exposing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect positional information of a surface to be detected in normal line direction by reducing an influence of a pattern or a reflectance distribution of the surface to be detected. <P>SOLUTION: An apparatus for irradiating measuring light L1 to a reticle surface Ra to receive the reflected light L2 from the reticle surface Ra by a photoelectric sensor 37, detecting surface position information of the reticle surface Ra includes: a confocal optical system including an objective lens 35 for receiving the reflected light L2 by irradiating the measuring light L1 to the reticle surface Ra and a pinhole plate 36 for passing the reflected light L2 through the objective lens 35 to the photoelectric sensor 37; and a phase plate 33 for imparting a phase distribution so as to widen an irradiation area of the measuring light L1 on the reticle surface Ra and so as to narrow the irradiation area of the reflected light L2 on the pinhole plate 36. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a surface position detecting device for detecting surface position information of a surface to be examined, an exposure device provided with the surface position detecting device, and an electronic device (microdevice) such as a semiconductor element or a liquid crystal display device using the exposure device. ) For manufacturing a device.

  Batch exposure projection exposure such as a stepper used to transfer a reticle (mask) pattern onto a photoresist-coated wafer (or glass plate, etc.) in a lithography process for manufacturing a semiconductor element or the like In an exposure apparatus such as an apparatus or a scanning projection exposure apparatus such as a scanning stepper, the surface of the wafer (wafer surface) is adjusted within the range of the depth of focus (DOF) with respect to the image plane of the projection optical system. The height of the wafer stage is controlled based on the measurement value of an oblique incidence type autofocus sensor (hereinafter referred to as an AF sensor) that irradiates the wafer surface with detection light obliquely and detects the reflected light. .

  Recently, in order to suppress a focus error due to the deflection of the reticle, the detection light is irradiated almost perpendicularly to the pattern surface (test surface) of the reticle through an objective lens driven in the optical axis direction. A confocal method for a reticle that detects the position (surface position) in the normal direction of the test surface by detecting the reflected light through a pinhole at a position conjugate with the objective lens and the test surface. An AF sensor is also used (see, for example, Patent Document 1).

JP 2007-48823 A

  According to a conventional confocal AF sensor for a reticle, the detection surface can be irradiated with detection light almost perpendicularly, so that the optical system can be downsized compared to the oblique incidence method. However, since various patterns for the device are formed on the pattern surface of the reticle that is the test surface, the amount of reflected light depends on the distribution of the pattern in the focused spot of the detection light on the test surface. There is a risk that the center of the distribution and the center of the pinhole will be relatively deviated and a detection error of the surface position will occur.

  In view of such a problem, the present invention reduces the influence of the pattern or reflectance distribution of the test surface, and can detect the surface position information of the test surface with high accuracy, and this surface position detection device It is an object of the present invention to provide an exposure apparatus using the above and a device manufacturing method using the exposure apparatus.

  The first surface position detection apparatus according to the present invention irradiates a test surface with detection light and receives the reflected light from the test surface via a photoelectric detector based on detection information obtained. In a surface position detection device for detecting surface position information of a surface, an objective lens that irradiates the test surface with the detection light and receives the reflected light, and a photoelectric detector that reflects the reflected light through the objective lens And a confocal optical system including an aperture member formed with an aperture that passes through the first surface, and a phase distribution that gives the detection light irradiated on the test surface to expand the irradiation area on the test surface. 1 phase member, and the 2nd phase member which provides phase distribution so that the irradiation area on the opening member may be narrowed to the reflected light.

  Further, the second surface position detection apparatus according to the present invention irradiates the test surface disposed on or near the first surface with the detection light, and photoelectrically detects the reflected light of the detection light from the test surface. In the surface position detection device for detecting the surface position information of the surface to be detected based on the imaging optical system that optically conjugates the first surface and the second surface, and disposed on the second surface, A confocal optical system including an aperture member formed with an aperture for limiting the region on the second surface through which the reflected light can pass to a predetermined range, and irradiating the first surface via the imaging optical system A first phase member for imparting a first phase distribution to the detected light and a second phase for imparting a second phase distribution to the reflected light guided to the second surface via the imaging optical system A first phase distribution of which the irradiation region of the detection light on the first surface is the imaging light A phase distribution which is larger than the conjugate image of the aperture by the system, and the second phase distribution is such that the irradiation area on the second surface of the reflected light from the test surface is smaller than the aperture. The phase distribution is equal.

  Further, the third surface position detection device according to the present invention is, as the first and second phase members of the second surface position detection device, detecting the irradiation of the first surface via the imaging optical system. A first phase member that gives a predetermined phase difference between the first partial detection light and the second partial detection light of the light, and the reflected light guided to the second surface via the imaging optical system The first partial reflected light corresponding to the first partial detection light and the second partial reflected light corresponding to the second partial detection light are provided with a phase difference that eliminates the predetermined phase difference. A two-phase member.

  An exposure apparatus according to the present invention is an exposure apparatus that projects an image of a mask pattern onto a substrate via a projection optical system to expose the substrate, the surface position detection device according to the present invention, and its surface position detection. A stage device for focusing an image of the mask pattern and the substrate on the basis of surface position information in the optical axis direction of the projection optical system of the pattern surface of the mask detected by the apparatus. is there.

  The device manufacturing method according to the present invention includes a step of exposing a substrate using the exposure apparatus of the present invention and a step of processing the exposed substrate.

  According to the surface position detection device of the present invention, the irradiation area of the detection light on the test surface is increased by the first phase member, so that the influence of the pattern of the test surface or the reflectance distribution is reduced. Furthermore, since the irradiation area of the reflected light on the aperture of the aperture member is reduced by the second phase member, the surface position information of the test surface can be detected with high accuracy.

1 is a partially cutaway view showing a schematic configuration of an exposure apparatus according to a first embodiment. 1A is a partially cutaway view showing the RAF sensor 2 and the RAF control system 52 in FIG. 1, FIG. 2B is a plan view showing the phase plate 33 in FIG. 2A, and FIG. The figure which shows the detection signal of a sensor, (D) is a figure which shows the focus signal obtained by processing the detection signal. (A) is a diagram showing the action of the phase plate 33 on the measurement light, (B) is a diagram showing the action of the phase plate 33 on the reflected light, and (C) is an enlarged plan view showing an irradiation area on the reticle surface of the measurement light. (D) is an enlarged plan view showing an irradiation region on a pinhole of reflected light. (A) is an enlarged plan view showing an irradiation region of measurement light when there is no phase plate, and (B) is an enlarged plan view showing an irradiation region of reflected light by the measurement light of FIG. 4 (A). (A) is a plan view showing a flat plate 33U having no phase difference region, (B) is an enlarged view showing an irradiation region of measurement light transmitted through the flat plate 33U, (C) is a plan view showing the phase plate 33, (D). FIG. 4 is an enlarged view showing an irradiation region of measurement light transmitted through the phase plate 33. (A) is a plan view showing the phase plate 33A, (B) is an enlarged view showing an irradiation region of the measurement light transmitted through the phase plate 33A, (C) is a plan view showing the phase plate 33B, and (D) is a phase plate. It is an enlarged view which shows the irradiation area | region of the measurement light which permeate | transmitted 33B. It is the figure which notched a part which shows RAF sensor 2A of 2nd Embodiment. It is a flowchart which shows an example of the manufacturing process of an electronic device.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In this embodiment, the present invention is applied to an exposure apparatus provided with an autofocus sensor for a reticle.
FIG. 1 is a view showing a schematic configuration of a scanning exposure type exposure apparatus (projection exposure apparatus) comprising a scanning stepper according to the present embodiment. In FIG. 1, the exposure apparatus includes an exposure light source (not shown), an illumination optical system IL that illuminates a reticle R (mask) with exposure light from the exposure light source, and a circuit pattern for transfer on a lower surface (pattern surface). A reticle stage RST that holds and moves the formed reticle R, a projection optical system PL that projects an image of the pattern of the reticle R onto a wafer W (substrate) coated with a photoresist (photosensitive material), and a wafer W And a wafer stage WST that moves while holding. Further, the exposure apparatus is referred to as a reticle autofocus sensor (hereinafter referred to as RAF sensor) for detecting the position in the normal direction (here, the direction parallel to the optical axis of the projection optical system PL) on the lower surface of the reticle R. ) 2, a wafer autofocus sensor (hereinafter referred to as AF sensor) 60 for detecting the position (focus position) of the projection optical system PL in the optical axis direction at a plurality of measurement points on the surface of the wafer W, and RAF. From a focusing mechanism (image position correcting mechanism) that focuses the surface of the wafer W on the image plane of the projection optical system PL based on the measurement results of the sensor 2 and the AF sensor 60, and a computer that controls the overall operation of the apparatus. Main control system 50 and the like.

  Hereinafter, the Z-axis is taken in parallel to the optical axis AX of the projection optical system PL, and the X-axis is set in the direction perpendicular to the plane of FIG. 1 in the plane perpendicular to the Z-axis (here, almost horizontal plane). A description will be given by taking the Y axis in a parallel direction. In the present embodiment, the direction parallel to the Y axis (Y direction) is the scanning direction SD of the reticle R and wafer W during scanning exposure. Further, the rotation directions around the axes parallel to the X axis, the Y axis, and the Z axis are also referred to as θx, θy, and θz directions.

  In FIG. 1, an illumination optical system IL includes an optical system 4 including a light amount adjusting optical system, an illuminance uniformizing optical system including an optical integrator, a reticle blind (field stop), a relay lens system, and the like; a condenser lens 6; And a mirror 8 for bending the optical path. As an exposure light source (not shown), an ultraviolet laser light source such as a KrF excimer laser (wavelength 248 nm) or an ArF excimer laser (wavelength 193 nm), a harmonic generator of a solid-state laser (semiconductor laser, etc.), or a mercury lamp (i-line etc.) Or the like.

  A reticle stage RST that holds the reticle R is mounted on an upper surface substantially parallel to the XY plane of the reticle base RBS so as to be movable via an air bearing, and is driven in the Y direction by a drive mechanism (not shown) such as a linear motor. In addition to being driven at a constant speed, it can also be finely driven in the X direction and the θz direction. On the reticle stage RST, a reference mark or the like is formed on the lower surface so as to be close to the reticle R in the Y direction, and the reticle mark plate RFM having a narrower width in the Y direction than the reticle R is held. The reticle R and the reticle mark Openings 10a and 10b for allowing exposure light and measurement light from the RAF sensor 2 to pass are formed in the reticle stage RST on the bottom side of the plate RFM. An opening 10c for allowing exposure light to pass is formed in a region including the optical axis AX of the reticle base RBS, an opening 10d is formed in a region away from the optical axis AX in the Y direction, and the reticle R and the reticle mark plate are formed through the opening 10d. The lower surface of the RFM is irradiated with measurement light (detection light) from the RAF sensor 2 (details will be described later).

  Further, a laser interferometer 13 that irradiates the movable mirror 12 with a measurement laser beam is disposed so as to face the movable mirror 12 fixed on the reticle stage RST. The moving mirror 12 actually includes X-axis and Y-axis moving mirrors, and the laser interferometer 13 also includes at least two Y-axis laser interferometers and an X-axis laser interferometer. The laser interferometer 13 uses, for example, a reference mirror (not shown) provided on the side surface of the projection optical system PL as a reference, and at least the position of the reticle stage RST in the Y direction and X direction with a resolution of about 0.5 to 0.1 nm. Measure the rotation angle in the θz direction. This measurement value is supplied to a stage control unit in the main control system 50, and the stage control unit controls the two-dimensional position and speed of the reticle stage RST via a drive mechanism (not shown) based on the measurement value. .

  Projection optical system PL is a birefringent or catadioptric system that is telecentric on both sides (or one side on the wafer side) and has a projection magnification of 1/4 or 1/5, etc., and is elongated in the X direction on the lower surface of reticle R. An image of the pattern in the area is projected onto an exposure area on one shot area on the wafer W. Lens elements via three drive elements (piezo elements, etc.) 57A and 57B and lens frames 56A and 56B that can be expanded and contracted in the Z direction within the divided lens barrels 55A and 55B that are part of the lens barrels of the projection optical system PL. 58A and 58B are supported. The drive amounts of the drive elements 57A and 57B are controlled by the drive system 54 under the control of the main control system 50. By controlling the position of the lens elements 58A and 58B in the Z direction and the tilt angles in the θx and θy directions via the drive elements 57A and 57B, the imaging characteristics such as the field curvature and the best focus position of the projection optical system PL are controlled. Can be controlled. An imaging characteristic control mechanism of the projection optical system PL is configured including the drive elements 57A and 57B and the drive system 54. Note that the number and position of lens elements (or optical members) in the projection optical system PL driven by the imaging characteristic control mechanism are set according to the type of imaging characteristics to be controlled.

  On the other hand, wafer W is sucked and held on wafer stage WST via wafer holder WH. Wafer stage WST controls wafer table 21 to which wafer holder WH is fixed, XY stage 23, and the position (focus position) of wafer table 21 with respect to XY stage 23 and the tilt angles in the θx and θy directions. 3 Z drive parts 22A, 22B, and 22C for carrying out are provided. The XY stage 23 is mounted on a guide surface substantially parallel to the XY plane on the wafer base WBS so as to be movable via an air bearing, and is driven at a constant speed in the Y direction by a drive mechanism (not shown) such as a linear motor. At the same time, it is driven to move stepwise in the X and Y directions.

  Laser interferometer 24 (actually, for example, at least one axis in the Y direction and the X direction) irradiates a measurement laser beam on the reflecting surface so as to face the orthogonal reflecting surface (which may be a moving mirror) of the wafer table 21. Are constructed of two-axis laser interferometers). The laser interferometer 24 uses, for example, a reference mirror (not shown) provided on the side surface of the projection optical system PL as a reference, and at least the position of the wafer table 21 (wafer W) in the X direction and Y direction is 0.5 to 0.1 nm. It measures with a resolution of about, and also measures the rotation angle in the θz direction. This measurement value is supplied to a stage control unit in main control system 50, and the stage control unit controls the two-dimensional position and speed of wafer stage WST via a drive mechanism (not shown) based on the measurement value. .

  An alignment sensor ALG for detecting the position of the alignment mark on the wafer W is installed on the side surface of the projection optical system PL, and a reference mark plate in which slits and reference marks are formed in the vicinity of the wafer W on the wafer table 21. An aerial image measurement system 25 is installed that includes 25a, a lens system 25b that collects the exposure light that has passed through the slit, and a photoelectric sensor 25c that receives the collected light flux. The aerial image measurement system 25 can also measure the position of the alignment mark image on the reticle R. Detection signals from the alignment sensor ALG and the aerial image measurement system 25 are supplied to an alignment control unit in the main control system 50, and the alignment control unit aligns the reticle R and the wafer W based on the detection signals.

  Further, the AF sensor 60 projects a slit image obliquely to a plurality of measurement points on the surface of the wafer W, receives light reflected from the surface, re-forms the slit image, and the amount of lateral displacement thereof. In addition, this is an oblique incidence type multi-point autofocus sensor, which is composed of a light receiving unit 60b that outputs a detection signal corresponding to the position (focus position) in the Z direction of the measurement point. The detection signal of the light receiving unit 60b is supplied to the wafer side focus calculation unit in the main control system 50, and the wafer side focus calculation unit processes the detection signal to obtain the focus position and tilt angle of the wafer W surface.

  The reticle-side focus calculation unit in the main control system 50 also includes position information in the Z direction of the lower surface (pattern surface) of the reticle R measured via the RAF sensor 2 and the RAF control system 52, as will be described later. Supplied. Based on this position information, the reticle-side focus calculation unit calculates the position in the Z direction of the reduced image of the pattern of the reticle R by the projection optical system PL, and the inclination angle (or the curvature of field in the θx direction and θy direction). Status). At the time of scanning exposure, the focus drive unit in the main control system 50 focuses the surface of the wafer W obtained by the wafer side focus calculation unit on the image plane of the projection optical system PL calculated by the reticle side focus calculation unit. As described above, the Z drive units 22A to 22C are driven by the autofocus method, and the curvature of field or the focus position of the projection optical system PL is controlled via the imaging characteristic control mechanism (drive system 54) as necessary. . That is, the Z driving units 22A to 22C and the imaging characteristic control mechanism (driving system 54) constitute a focusing mechanism (image position correcting mechanism). As a result, even when a slight deflection occurs on the lower surface (pattern forming surface) of the reticle R, the surface of the wafer W is focused on the image surface of the projection optical system PL, and the pattern of the reticle R can be obtained with high resolution. It can be transferred to each shot area of the wafer W.

  At the time of scanning exposure, on the wafer W via the wafer stage WST in synchronization with the movement of the reticle R in the Y direction via the reticle stage RST with respect to the illumination area of the exposure light from the illumination optical system IL. The movement of one shot area in the Y direction with the projection magnification as the speed ratio and the operation of stopping the exposure light irradiation and moving the wafer W stepwise in the X and Y directions via the wafer stage WST Repeated. By such a step-and-scan operation, an image of the pattern of the reticle R is exposed to each shot area on the wafer W.

  Next, in the present embodiment, the RAF sensor for measuring the distribution of the position in the Z direction (Z position) caused by the deflection of the lower surface (pattern surface) of the reticle R that causes the focus error of the projection optical system PL. 2 and the RAF control system 52 that processes this detection signal will be described in detail. Note that the measurement of the Z position of the reticle R by the RAF sensor 2 and the RAF control system 52 is performed, for example, after exchanging the reticle on the reticle stage RST of FIG. In the subsequent exposure process using the same reticle, autofocus control is performed based on the Z position corresponding to the position in the scanning direction of the reticle R that is measured and stored first.

  2A shows the RAF sensor 2 and the RAF control system 52 disposed between the side surface of the upper end portion of the projection optical system PL of FIG. 1 and the reticle base RBS. In FIG. 2A, the RAF sensor 2 is arranged below the opening 10d of the reticle base RBS, and the reticle R and the reticle mark plate RFM held by the reticle stage RST above the opening 10d are in the Y direction (scanning direction SD). ) In FIG. 2A, the pattern surface Ra on the lower surface of the reticle R is positioned above the RAF sensor 2 as a test surface. The RAF sensor 2 includes a light source 31 that generates measurement light L1 radially in the + Y direction as a point light source such as a semiconductor laser or a light emitting diode. The measurement light L1 is, for example, monochromatic light from the visible range to the near infrared range, and the wavelength thereof is 670 nm as an example. The RAF control system 52 controls the light emission timing and output of the light source 31.

  The RAF sensor 2 includes an objective lens 35 that is sequentially arranged along the optical axis axr below the pattern surface Ra of the reticle R, an aperture stop 34, a later-described phase plate 33 that transmits the measurement light L1, and a prism. A type beam splitter 32, a pinhole plate 36 in which a pinhole 36a is formed, and a photoelectric sensor 37 such as a photodiode. The objective lens 35 substantially optically conjugates the light emitting portion of the light source 31 and the irradiation region of the measurement light L1 on the pattern surface Ra, and also connects the irradiation region of the measurement light L1 on the pattern surface Ra and the pinhole 36a. Substantially optically conjugate. In other words, the objective lens 35 and the pinhole plate 36 constitute a confocal optical system for the pattern surface Ra. However, since the pattern surface Ra tends to be slightly bent, for example, in an arc shape due to the weight of the reticle R, for example, an average plane in the Y direction of the pattern surface Ra that is empirically obtained is defined as the reference surface 11. To do. As an example, the reference surface 11 is at the same Z position as the design object surface of the projection optical system PL on the optical axis AX of the projection optical system PL, and the irradiation area of the measurement light L1 on the pattern surface Ra is on the reference surface 11. When they match, the irradiation area and the light emitting portion of the light source 31 and the pinhole 36a are accurately optically conjugate. For example, the lower surface (pattern surface) of reticle mark plate RFM may be used as reference surface 11.

  The arrangement surface of the aperture stop 34 is optically conjugate with the exit pupil of the confocal optical system (here, the same as the exit pupil of the objective lens 35), and the phase plate 33 is on a surface in the vicinity of the aperture stop 34. Has been placed. The numerical aperture NA of the measurement light L1 irradiated from the objective lens 35 to the pattern surface Ra is, for example, 0.5. In this case, of the measurement light L1 emitted from the light source 31, the measurement light reflected in the direction of the reticle R (+ Z direction) by the beam splitter 32 (also referred to as L1) passes through the phase plate 33 and the aperture stop 34. Then, the light is condensed on the pattern surface Ra by the objective lens 35. Then, the reflected light L2 reflected by the pattern surface Ra in the measurement light L1 returns to the beam splitter 32 through the objective lens 35, the aperture stop 34, and the phase plate 33, and the reflected light transmitted through the beam splitter 32 (also this L2) passes through the pinhole 36a and is received by the photoelectric sensor 37. A detection signal FS1 of the photoelectric sensor 37 is output to the RAF control system 52.

  The size of the pinhole 36a is set to be larger than the irradiation area (spot light) of the reflected light L2 from the pattern surface Ra in a state where the pattern surface Ra matches the reference surface 11. When the Z position of the pattern surface Ra moves away from the reference surface 11, the irradiation area of the reflected light L2 increases, and the amount of light that passes through the pinhole 36a in the reflected light L2 decreases, so the detection signal FS1 is small. Become. Therefore, when the objective lens 35 is at rest, the detection signal FS1 is generated when the Z position zf of the irradiation region of the measurement light L1 on the pattern surface Ra is the Z position of the reference surface 11 as shown in FIG. It becomes maximum when it coincides with z0, and becomes smaller when the Z position zf moves away from z0.

  In FIG. 2A, the lens holder 38 that holds the objective lens 35 is supported so as to be displaceable in the Z direction with respect to a frame (not shown) through, for example, a leaf spring (not shown). A voice coil motor that vibrates the objective lens 35 in the Z direction is constituted by the wound coil 39 and a magnetic member 40 that is fixed to the frame and generates a magnetic field across the coil 39. The RAF control system 52 controls the current flowing through the coil 39 to vibrate the objective lens 35 in the Z direction at a predetermined cycle. Further, as an example, the RAF control system 52 synchronously rectifies the detection signal FS1 from the photoelectric sensor 37 with a signal synchronized with the drive current of the coil 39, and as shown in FIG. A focus signal FS2 that changes in proportion to the difference (defocus amount) between the position zf and the Z position z0 of the reference plane 11 (here, the designed object plane) is generated.

  The focus signal FS2 is supplied to a reticle-side focus calculation unit in the main control system 50 of FIG. 1, and the reticle-side focus calculation unit multiplies the focus signal FS2 by a conversion factor obtained in advance, and the reticle at this time The Z position zf of the pattern surface Ra is obtained in correspondence with the Y coordinate of the stage RST (reticle R). At this time, the distance in the Y direction between the optical axis axr of the RAF sensor 2 and the optical axis AX of the projection optical system PL (in this embodiment, matches the center of the illumination area by the exposure light) (base line of the RAF sensor 2). Is obtained in advance and stored in a storage device in the main control system 50. The reticle-side focus calculation unit obtains the Z position zf of the pattern surface Ra obtained when the reticle stage RST is moved in the Y direction at a predetermined interval, whereby the Z position distribution (deflection amount) of the pattern surface Ra is obtained. ) Based on the distribution of the Z position of the pattern surface Ra, the reticle-side focus calculation unit corresponds to the Y coordinate of the reticle stage RST (reticle R) during scanning exposure, and the pattern image of the reticle R by the projection optical system PL. Information such as the position of the surface in the Z direction is obtained, and this information is supplied to the focus drive unit in the main control system 50.

  Next, the configuration and operation of the phase plate 33 in the RAF sensor 2 of FIG. As shown in FIG. 2B, the phase plate 33 is divided into an inner central region 33a and an outer peripheral region 33c with a circumferential step portion 33b centered on the optical axis axr. The outer shape of the phase plate 33 is a disc shape, but the outer shape may be a square shape or the like. In this case, the measurement light L1 passes through the entire surface of the central region 33a and part of the peripheral region 33c, and the measurement light L1 that has passed through the central region 33a is reflected by the pattern surface Ra, and again as the reflected light L2, the phase plate 33. Is transmitted through the central region 33a. Similarly, the measurement light L1 that has passed through the peripheral region 33c is reflected by the pattern surface Ra, and again passes through the peripheral region 33c of the phase plate 33 as reflected light L2.

  3A and 3B are enlarged sectional views showing the phase plate 33 in FIG. 2A, respectively. As shown in FIG. 3A, the level difference d between the central region 33a inside the phase plate 33 and the peripheral region 33c surrounding the central region 33a is measured light L1 that passes through the central region 33a and measurement light that passes through the peripheral region 33c. The optical path length difference ΔOP1 is set so as to occur between L1 and the wavelength of the measurement light L1 as λ. Although k is an arbitrary integer, k is preferably 0 for practical use.

ΔOP1 = λ / 2 + k · λ (1)
Note that the optical path length difference ΔOP1 in the equation (1) is equivalent to λ / 2. Further, the optical path length difference ΔOP1 in the equation (1) is equivalent to (180 ° + k · 360 °) in phase difference, that is, an odd multiple of 180 °, but this phase difference is equivalent to 180 °.
The optical path length difference between the wavefront L1aw of the measurement light L1 that has passed through the central region 33a of the phase plate 33 and the wavefront L1cw of the measurement light L1 that has passed through the peripheral region 33c is λ / 2 (180 ° in phase difference). The intensity distribution of the measurement light L1 collected on the optical axis axr of the pattern surface Ra is reduced by the interference of two light beams having a phase difference of 180 °. Therefore, as shown in FIG. 3C, the irradiation region 41 of the measurement light L1 on the pattern surface Ra is wider than the irradiation region 41A indicated by the dotted line when there is no phase plate 33. As an example, assuming that the irradiation region 41A without the phase plate 33 is a circular region having a diameter of about 1 to 2 μm, the irradiation region 41 when the phase plate 33 is used has an area with a diameter of about several μm (for example, 5 μm). Becomes a circular region of 4 times or more.

As a result, even if the circuit pattern 42 for transfer (acting as a part having a high reflectance) is formed on the pattern surface Ra, the ratio of the area of the circuit pattern 42 to the area of the irradiation region 41 is small, so the pattern surface Ra Since the light amount distribution of the reflected light L2 from the light source is not significantly affected, the Z position of the pattern surface Ra can be detected with high accuracy.
In addition, the reflected light L2 from the pattern surface Ra by the measurement light L1 transmitted through the central region 33a and the peripheral region 33c of the phase plate 33 again becomes the central region 33a and the central region 33a of the phase plate 33, respectively, as shown in FIG. It passes through the peripheral region 33c. Therefore, the next optical path length difference ΔOP2 that is twice the expression (1) occurs between the wavefront L2aw of the reflected light L2 transmitted through the central region 33a and the wavefront L2cw of the reflected light L2 transmitted through the peripheral region 33c. .

ΔOP2 = λ + 2 · k · λ (2)
Since this optical path length difference ΔOP2 is an integral multiple of λ, it is substantially equivalent to the case where the optical path length difference is zero. Further, the optical path length difference ΔOP2 in the expression (2) is (360 ° + 2 · k · 360 °) in terms of phase difference, that is, an integer multiple of 360 °, but this phase difference is equivalent to 0 °.
Accordingly, the phase of the equivalent wavefront L2aw ′ of the reflected light L2 that passes through the central region 33a of the phase plate 33 and the wavefront L2cw of the reflected light L2 that passes through the peripheral region 33c become equal, so that the wavefront of the reflected light L2 is in phase. It becomes substantially equal to the wavefront when the plate 33 is not present. As a result, as shown in FIG. 3D, the irradiation region 43 of the reflected light L2 collected in the pinhole 36a of the pinhole plate 36 is a circular region having the same size as when the phase plate 33 is not used. Thus, the Z position of the pattern surface Ra can be measured with high sensitivity.

  Further, as shown in FIG. 3A, even if the circuit pattern 42 exists on the pattern surface Ra, the ratio of the light flux from the circuit pattern 42 to the irradiation region 43 of the reflected light L2 in the pinhole 36a is the pattern. The ratio is the same as the ratio of the circuit pattern 42 to the wide irradiation region 41 on the surface Ra, which is small. Accordingly, since the center of light quantity of the irradiation region 43 in the pinhole 36a is substantially in the vicinity of the optical axis axr, the pinhole 36a and the irradiation region can be obtained even when the objective lens 35 in FIG. Since the relative position to 43 hardly changes, the Z position of the pattern surface Ra can be measured with high accuracy.

  On the other hand, when the phase plate 33 is not provided in the RAF sensor 2, as shown in FIG. 4A, the irradiation region 41A of the measurement light L1 on the pattern surface Ra is a circuit on the pattern surface Ra. The size is about twice the width of the pattern 42, and the intensity distribution of the irradiation region 41A is largely asymmetric in the Y direction. Accordingly, the irradiation region 43A of the reflected light L2 from the pattern surface Ra within the pinhole 36a is largely asymmetric in the Y direction with respect to the optical axis axr, as shown in FIG. 4B, so that the RAF sensor 2 (A ) When the objective lens 35 is driven in the Z direction, the detection signal FS1 of the photoelectric sensor 37 may be distorted. In particular, when the defocus amount of the pattern surface Ra from the reference surface 11 is increased, the error of the focus signal FS2 is increased. There is a risk of growing.

The shape and line width of the circuit pattern on the pattern surface Ra are various, but when the irradiation region 41 of the measurement light L1 on the pattern surface Ra is wide as in the present embodiment, the irradiation region 41 The influence of the circuit pattern or the reflectance distribution on the pattern surface Ra can be reduced in proportion to the area.
Next, for various examples of the phase plate 33 in FIG. 2A, the results of obtaining the shape of the irradiation region of the measurement light L1 on the pattern surface Ra by computer simulation are shown in FIGS. This will be described with reference to FIGS. 5D and 6A to 6D. The conditions at this time were such that the wavelength λ of the measurement light L1 was 670 nm and the numerical aperture NA of the objective lens 35 was 0.5. In the following, the outer shape of the phase plate is a square, but the outer shape may be a circle or the like.

First, as a comparative example, FIG. 5A shows a case where a flat plate 33 </ b> U that transmits the measurement light L <b> 1 and has no phase difference is arranged instead of the phase plate 33. In this case, the irradiation area of the measurement light L1 on the pattern surface Ra is a circular area having a diameter of about 0.8 μm as shown in FIG.
On the other hand, the phase plate 33 in FIG. 5C is obtained by converting the radius of the step portion 33b surrounding the central region 33a to 0.8 × NA in terms of the numerical aperture NA. At this time, the radius of the measurement light L1 in the peripheral region 33c corresponds to the numerical aperture NA, and the optical path length difference of λ / 2 (180 ° difference between the measurement light L1 transmitted through the central region 33a and the peripheral region 33c). Phase difference). In this case, the irradiation area of the measurement light L1 on the pattern surface Ra is expanded to a circular area having a diameter of about 2 μm, as shown in FIG.

  Further, in the phase plate 33A of FIG. 6A, the radius of the stepped portion 33b surrounding the central region 33a is 0.7 × NA. In this case, the irradiation area of the measurement light L1 on the pattern surface Ra is an annular area having an inner diameter of about 0.8 μm and an outer diameter of about 3.5 μm, as shown in FIG. Since the influence of the circuit pattern on the pattern surface Ra is reduced even in such an annular irradiation region, the phase plate 33A can be used instead of the phase plate 33 in FIG.

  Further, the phase plate 33B of FIG. 6C has a measuring light beam by a step portion 33b3 having a radius of 0.5 × NA, a step portion 33b2 having a radius of 0.7 × NA, and a step portion 33b1 having a radius of 0.87 × NA. The L1 incident surface is divided into a central region including the optical axis, a first annular region surrounding it, a second annular region surrounding it, and a peripheral region surrounding it, and a central region and a second annular region An optical path length difference of λ / 2 (a phase difference of 180 °) between the measurement light transmitted through the first region 33a and the measurement light transmitted through the second region 33c composed of the first annular region and the peripheral region. ).

  In this case, as shown in FIG. 6D, the irradiation area of the measurement light L1 on the pattern surface Ra includes a first annular zone area having an inner diameter of about 0.8 μm and an outer diameter of about 1.5 μm, and an inner diameter. Is divided into a second annular zone region having an outer diameter of about 5 μm and an outer diameter of about 7 μm. The phase plate 33B can be used in place of the phase plate 33 in FIG. 2A because the influence of the circuit pattern on the pattern surface Ra is reduced even in such a double ring-shaped irradiation region. .

The effect of this embodiment is as follows.
(1) The detection apparatus including the RAF sensor 2 and the RAF control system 52 in FIG. 2A of the present embodiment irradiates the measurement light L1 onto the pattern surface Ra of the reticle R, and applies the reflected light L2 from the pattern surface Ra. In a detection device that detects a position (surface position) in the normal direction of the pattern surface Ra based on a detection signal FS1 obtained by receiving light through the photoelectric sensor 37, the measurement light L1 is applied to the pattern surface Ra to be reflected light. A confocal optical system including an objective lens 35 that receives L2 and a pinhole plate 36 formed with a pinhole 36a through which reflected light L2 passing through the objective lens 35 passes through the photoelectric sensor 37, and the pattern surface Ra are irradiated. A phase plate 33 that imparts a phase distribution to the measurement light L1 so as to widen the irradiation area on the pattern surface Ra and to narrow the irradiation area on the pinhole plate 36 to the reflected light L2. It includes those were.

  Further, the detection device irradiates the measurement light L1 to the pattern surface Ra of the reticle R arranged at or near the reference surface 11 (first surface), and photoelectrically detects the reflected light L2 of the measurement light L1 by the reticle R. In the detection device that detects surface position information of the pattern surface Ra based on the result, the objective lens 35 that optically conjugates the reference surface 11 and the arrangement surface (second surface) of the pinhole plate 36, and the arrangement surface thereof A confocal optical system including a pinhole plate 36 in which a pinhole 36a is formed that restricts a region on the arrangement surface through which the reflected light L2 can pass to a predetermined range, and a reference through the objective lens 35. A phase that imparts a first phase distribution to the measurement light L1 irradiated to the surface 11 (pattern surface Ra) and a second phase distribution to the reflected light L2 that is guided to the arrangement surface via the objective lens 35. Board 33 It is equipped with a. The first phase distribution is set so that the irradiation region 41 of the measurement light L1 on the reference surface 111 (pattern surface Ra) is larger than the conjugate image of the pinhole 36a by the objective lens 35. Is set such that the irradiation area of the reflected light L2 from the pattern surface Ra on the arrangement surface of the pinhole plate 36 is smaller (or may be substantially equal) than the pinhole 36a.

According to this embodiment, since the irradiation area of the measurement light L1 on the pattern surface Ra is increased by the phase plate 33, the influence of the pattern on the pattern surface Ra or the reflectance distribution is reduced. Furthermore, since the irradiation area of the reflected light L2 on the pinhole 36a is reduced by the phase plate 33, the surface position information of the pattern surface Ra can be detected with high accuracy or high sensitivity.
(2) In addition, the phase plate 33 has two regions (a central region 33a and a peripheral region 33c) that give a 180 ° phase difference to the transmitted measurement light L1, and the phase plate 33 reflects the transmitted reflected light L2. It has two regions (a central region 33a and a peripheral region 33c) that give a phase difference of 180 °. Therefore, the phase plate 33 can be easily manufactured with high accuracy.

Note that, as described using Expression (1), the 180 ° phase difference is equivalent to an odd multiple of 180 °. Actually, in consideration of manufacturing errors of the phase plate 33, the phase difference can be allowed to be up to about ± 10% with respect to 180 °.
Moreover, the area | region which provides the different phase difference on the phase plate 33 may be divided into 3 or more like the phase plate 33B of FIG.6 (C).

  Furthermore, the point is that the irradiation area of the measurement light L1 on the pattern surface Ra only needs to be widened. Therefore, the phase plate 33 may be provided with at least two regions that give a phase difference other than 180 ° (for example, 45 °). Is possible. In this case, for example, another phase plate for reducing the irradiation area of the reflected light L2 on the pinhole 36a may be added between the beam splitter 32 and the photoelectric sensor 37 in FIG. Good.

  (3) In the detection apparatus including the RAF sensor 2 of FIG. 2A, the phase plate 33 is the center of the measurement light L1 that is irradiated onto the reference surface 11 (pattern surface Ra) via the objective lens 35. A predetermined phase difference (a phase difference that widens the irradiation area on the pattern surface Ra) is given between the first partial measurement light transmitted through the region 33a and the second partial measurement light transmitted through the peripheral region 33c. The phase plate 33 transmits the first partially reflected light (the central region 33a) corresponding to the first partially measured light out of the reflected light L2 guided to the arrangement surface of the pinhole plate 36 through the objective lens 35. A phase difference for eliminating the predetermined phase difference is given between the reflected light L2) and the second partial reflected light corresponding to the second partial measurement light (reflected light L2 transmitted through the peripheral region 33c). .

Accordingly, since the irradiation area of the measurement light L1 on the pattern surface Ra is increased by the phase plate 33, the influence of the pattern on the pattern surface Ra or the reflectance distribution is reduced. Furthermore, since the irradiation area of the reflected light L2 on the pinhole 36a is reduced by the phase plate 33, the surface position information of the pattern surface Ra can be detected with high accuracy.
(4) In this case, the phase difference that eliminates the predetermined phase difference is such that the phase difference between the first partially reflected light and the second partially reflected light on the pinhole plate 36 is an integral multiple of 360 °. It is a phase difference. Since the phase difference of an integral multiple of 360 ° is equivalent to 0 °, the irradiation area of the reflected light L2 is reduced to substantially the same size as when the phase plate 33 is not present.

(5) Further, the phase plate 33 is disposed in the vicinity of a position optically conjugate with the exit pupil of the confocal optical system. Therefore, the intensity distribution (irradiation region) on the object plane or the image plane can be controlled by giving a phase difference to the measurement light L1 on the phase plate 33. The phase plate 33 may be disposed on the exit pupil of the confocal optical system or on a position optically conjugate with the exit pupil.
(6) Further, in the example of FIG. 2A, the phase plate 33 serves as both the phase member for the measurement light L1 and the phase member for the reflected light L2, so that the configuration of the RAF sensor 2 can be simplified. .

(7) Moreover, it is preferable that the phase plate 33 expands the irradiation area of the measurement light L1 on the pattern surface Ra at least twice as compared with the case where the phase plate 33 is not used. Thereby, the influence of the pattern on the pattern surface Ra or the reflectance distribution can be reduced to ½ or less.
(8) Further, the exposure apparatus of the present embodiment projects an image of the pattern of the reticle R onto the wafer W via the projection optical system PL, and exposes the wafer W. In the exposure apparatus, the RAF sensor 2 and the RAF control are performed. A detection device including a system 52 is provided, and the detection device detects surface position information of the pattern surface Ra of the reticle R in the optical axis direction of the projection optical system PL. Further, the exposure apparatus corrects the positional relationship in the optical axis direction of the projection optical system PL between the pattern image of the reticle R and the wafer W based on detection information of the detection apparatus (stages 22A to 22C (stage). Device). Accordingly, even if the reticle R is bent or the like, the exposure surface of the wafer W can be focused with high precision on the image of the pattern on the reticle R, so that the pattern on the reticle R can be transferred onto the wafer W with high resolution. .

In this embodiment, one RAF sensor 2 is provided. In FIG. 2A, a plurality of (for example, three) RAF sensors having the same configuration as the RAF sensor 2 are arranged in the X direction. The Z position of the pattern surface Ra of the reticle R may be measured in parallel at a plurality of locations in the X direction (non-scanning direction). Accordingly, it is possible to measure the deflection of the pattern surface Ra in the direction parallel to the X axis.
[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 7, parts corresponding to those in FIG. 2A are denoted by the same or similar reference numerals, and detailed description thereof is omitted or simplified.

  FIG. 7 shows the RAF sensor (reticle autofocus sensor) 2A and the RAF control system 52 of this embodiment. In FIG. 7, the RAF sensor 2A includes an irradiation system 2AA that irradiates the measurement light L1 onto the pattern surface Ra of the reticle R, and a light reception system 2AB that receives the reflected light L2 from the pattern surface Ra. The irradiation system 2AA includes a light source 31 that generates the measurement light L1 in the + Y direction, a collimator lens 35A that converts the measurement light L1 into a parallel light beam, and a beam that reflects the measurement light L1 of the parallel light beam on the reticle R side (+ Z direction). A splitter 32, an aperture stop 34, and an objective lens 35B that condenses the measurement light L1 on the pattern surface Ra of the reticle R are provided. Further, the irradiation system 2AA is disposed between the collimator lens 35A and the beam splitter 32, and provides a first phase distribution to the measurement light L1 so as to enlarge the irradiation region of the measurement light L1 on the pattern surface Ra. Phase plate 33A. Similar to the first embodiment, the objective lens 35 </ b> B vibrates in the Z direction by a voice coil motor including a coil 39.

  The light receiving system 2AB collects the objective lens 35B that converts the reflected light L2 from the pattern surface Ra into a parallel light beam, the beam splitter 32 irradiated with the reflected light L2, and the reflected light L2 that has passed through the beam splitter 32. A focusing lens 35C, a pinhole plate 36 formed with a pinhole 36a through which the condensed reflected light L2 passes, and a photoelectric sensor 37 that receives the reflected light L2 that has passed through the pinhole 36a. . The light receiving system 2AB is disposed between the beam splitter 32 and the imaging lens 35C, and a second phase plate that imparts a phase distribution to the reflected light L2 so that an irradiation area on the pinhole 36a is reduced. 33B. In this case, the irradiation region (spot light) of the measurement light L1 on the pattern surface Ra (more precisely, the reference surface 11) and the pinhole 36a are optically conjugate by the objective lens 35B and the imaging lens 35C. The objective lens 35B, the imaging lens 35C, and the pinhole plate 36 constitute a confocal optical system.

  In the present embodiment, the first phase plate 33A is, for example, 180 between the first measurement light L1a that passes through the central region in the measurement light L1 and the second measurement light L1c that passes through the annular peripheral region. Add a phase difference of °. The size of the central region is set so that the irradiation region of the measurement light L1 on the pattern surface Ra is at least twice that when the phase plate 33A is not provided. The first measurement light L1a is reflected by the pattern surface Ra, and then passes through the central region of the second phase plate 33B as the first reflected light L2a. The second measurement light L1c is reflected by the pattern surface Ra. After that, the second reflected light L2c passes through the peripheral region of the second phase plate 33B. In this case, the second phase plate 33B gives a 180 ° phase difference between the first reflected light L2a that passes through the central region of the reflected light L2 and the second reflected light L2c that passes through the peripheral region. To do. Accordingly, there is substantially no phase difference between the first reflected light L2a and the second reflected light L2c (because the phase difference is eliminated), so that the reflected light L2 collected on the pinhole 36a The size of the irradiation area is reduced to the size when the phase plates 33A and 33B are not provided. Other configurations are the same as those of the first embodiment.

As described above, also in the present embodiment, the irradiation area of the measurement light L1 on the pattern surface Ra is increased by the first phase plate 33A, so that the influence of the pattern on the pattern surface Ra or the reflectance distribution is reduced. Furthermore, since the irradiation area of the reflected light L2 on the pinhole 36a is reduced by the second phase plate 33B, the surface position information of the pattern surface Ra can be detected with high accuracy.
In the present embodiment, the first phase plate 33A and the second phase plate 33B are disposed at positions substantially optically conjugate with each other via the beam splitter 32, the objective lens 35B, and the pattern surface Ra. Has been. As a result, the same phase plate as the first phase plate 33A can be used as the second phase plate 33B.

In the present embodiment, since the second phase plate 33B is disposed separately from the first phase plate 33A, the distribution of the phase difference imparted to the reflected light L2 by the second phase plate 33B is the pin It is possible to optimize the irradiation area of the reflected light L2 in the hole 36a to be smaller.
In the above embodiment, the present invention is applied when detecting the position in the normal direction of the reticle R. However, the present invention can also be applied when detecting the position in the normal direction of the surface of the wafer W. It is. That is, in the exposure apparatus of FIG. 1, an autofocus sensor having the same configuration as that of the RAF system 2 may be used as the AF sensor 60 for the wafer W.

  When an electronic device (or microdevice) such as a semiconductor device is manufactured using the exposure apparatus of the above embodiment, the electronic device performs function / performance design of the electronic device as shown in FIG. Step 222 for manufacturing a mask (reticle) based on this design step, Step 223 for manufacturing a substrate (wafer) that is a base material of the device and applying a resist, and a reticle pattern by the exposure apparatus of the above-described embodiment. Exposure process to substrate (sensitive substrate), development process of exposed substrate, substrate processing step 224 including heating (curing) and etching process of developed substrate, device assembly step (dicing process, bonding process, packaging process, etc.) 225) and the inspection step 226, etc. It is produced through.

Therefore, this device manufacturing method includes forming the pattern of the photosensitive layer on the substrate using the exposure apparatus of the above embodiment, and processing the substrate on which the pattern is formed (step 224). Yes. According to the exposure apparatus, since focusing can be performed with high accuracy, an electronic device can be manufactured with high accuracy.
In the above embodiment, the scanning exposure type exposure apparatus has been described as an example. However, the present invention can also be applied to a batch exposure type (step-and-repeat type) exposure apparatus such as a stepper. it can. Further, the present invention can be applied to an immersion type exposure apparatus disclosed in, for example, International Publication No. 2004/053955 pamphlet, European Patent Application Publication No. 1420298, International Publication No. 2005/122218 pamphlet or the like. It is.

The present invention can also be applied to the case where the surface position of a reticle and / or wafer is detected by a proximity type exposure apparatus that does not use a projection optical system.
In addition, the present invention is not limited to the application to the manufacturing process of a semiconductor device and a liquid crystal display element. For example, the manufacturing process of a plasma display or the like, an imaging element (CCD or the like), a micromachine, MEMS (Microelectromechanical Systems: It can be widely applied to manufacturing processes of various devices such as micro electromechanical systems), thin film magnetic heads, and DNA chips.

  As described above, the present invention is not limited to the above-described embodiment, and various configurations can be taken without departing from the gist of the present invention.

  R ... reticle, Ra ... pattern surface, PL ... projection optical system, W ... wafer, RST ... reticle stage, 2 ... RAF sensor, 31 ... light source, 33, 33A, 33B ... phase plate, 34 ... aperture stop, 35, 35B ... objective lens, 36a ... pinhole, 37 ... photoelectric sensor, 52 ... RAF control system

Claims (13)

A surface position detecting device for detecting surface position information of the test surface based on detection information obtained by irradiating the test surface with detection light and receiving reflected light from the test surface via a photoelectric detector In
A confocal system including an objective lens that irradiates the test surface with the detection light and receives the reflected light, and an aperture member in which an opening through which the reflected light through the objective lens passes through the photoelectric detector is formed. With optical systems;
A first phase member that imparts a phase distribution to the detection light applied to the test surface so as to widen an irradiation area on the test surface;
A second phase member that imparts a phase distribution to the reflected light so as to narrow an irradiation area on the aperture member;
A surface position detecting device comprising: Detecting the surface position information of the test surface based on the result of photoelectrically detecting the reflected light from the test surface by irradiating the test surface arranged at or near the first surface. In the surface position detection device,
An imaging optical system that optically conjugates the first surface and the second surface, and a region on the second surface that is disposed on the second surface and through which the reflected light can pass is limited to a predetermined range. A confocal optical system including an aperture member in which an aperture is formed;
A first phase member that imparts a first phase distribution to the detection light applied to the first surface via the imaging optical system;
A second phase member that imparts a second phase distribution to the reflected light guided to the second surface via the imaging optical system,
The first phase distribution is a phase distribution in which an irradiation region of the detection light on the first surface is larger than a conjugate image of the opening by the imaging optical system,
The surface position detecting device characterized in that the second phase distribution is a phase distribution in which an irradiation area on the second surface of the reflected light from the test surface is smaller than or substantially equal to the opening. . The first phase member has at least two regions that give a phase difference of 180 ° to the detection light passing therethrough,
The surface position detecting device according to claim 1, wherein the second phase member has at least two regions that give a 180 ° phase difference to the reflected light passing therethrough. Detecting the surface position information of the test surface based on the result of photoelectrically detecting the reflected light from the test surface by irradiating the test surface arranged at or near the first surface. In the surface position detection device,
An imaging optical system that optically conjugates the first surface and the second surface, and a region on the second surface that is disposed on the second surface and through which the reflected light can pass is limited to a predetermined range. A confocal optical system including an aperture member in which an aperture is formed;
A first phase member that imparts a predetermined phase difference between the first partial detection light and the second partial detection light of the detection light irradiated onto the first surface via the imaging optical system;
Of the reflected light guided to the second surface via the imaging optical system, a first partially reflected light corresponding to the first partially detected light and a second partially reflected light corresponding to the second partially detected light; A second phase member that imparts a phase difference that eliminates the predetermined phase difference,
A surface position detecting device comprising:   The phase difference for eliminating the predetermined phase difference is a phase difference in which a phase difference between the first partial reflected light and the second partial reflected light on the second surface is an integral multiple of 360 °. The surface position detection device according to claim 4.   The first phase member includes a first phase region that imparts a first phase to the first partial detection light, and an odd multiple of 180 ° relative to the first phase with respect to the second partial detection light. 6. The surface position detection device according to claim 4, further comprising a second phase region that provides a second phase that differs only by the second phase region.   The first phase member and the second phase member are arranged at positions optically conjugate with each other via at least a part of the imaging optical system and the first surface. And the surface position detection apparatus as described in any one of Claims 4-6.   The surface position detection apparatus according to claim 7, wherein the first phase member is disposed at a position optically conjugate with an exit pupil of the confocal optical system or a position in the vicinity thereof.   The surface position detecting device according to claim 7, wherein the first phase member also serves as the second phase member.   The first phase member has a circular first region centered on the optical axis of the confocal optical system, and a ring-shaped second region surrounding the first region, and the first region and the first region The surface position detection apparatus according to claim 1, wherein a phase difference of 180 ° is given to the detection light that has passed through the two regions.   11. The surface position detection apparatus according to claim 1, wherein the first phase member expands an irradiation area of the detection light on the surface to be measured at least twice. An exposure apparatus that projects an image of a mask pattern onto a substrate via a projection optical system to expose the substrate,
The surface position detection device according to any one of claims 1 to 11,
A stage device for focusing the image of the mask pattern and the substrate based on surface position information in the optical axis direction of the projection optical system of the pattern surface of the mask detected by the surface position detection device; An exposure apparatus comprising: Exposing the substrate using the exposure apparatus according to claim 12;
And a step of processing the exposed substrate.

Images