JP2005276932A - Aligner and device-manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform high precision exposure extending over a long time, without deteriorating optical performance of a projection optical system. <P>SOLUTION: A specific mirror Mc, which makes illumination light EL incident on a reflecting mask R at a prescribed incident angle, is held by an illumination system holding mount 56 which is separated physically from a body 26 holding a projection unit PU. Even if generation of heat (temperature rise) of the specific mirror resulting from irradiation of illumination light arises, transmission of heat is suppressed to an optical member, constituting the projection optical system in the projection unit by heat conduction. Thus, deterioration in the optical performance (including image forming characteristic) of the projection optical system due to thermal deformation of the optical member can be suppressed effectively. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus and a device manufacturing method, and more particularly to an exposure apparatus used in a lithography process for manufacturing a semiconductor element and the like and a device manufacturing method using the exposure apparatus.

  Conventionally, in a lithography process for manufacturing a semiconductor element, a liquid crystal display element, and the like, a resist or the like is applied to a pattern formed on a mask or a reticle (hereinafter collectively referred to as “reticle”) via a projection optical system. An exposure apparatus for transferring onto a substrate such as a wafer or a glass plate (hereinafter also referred to as a wafer as appropriate) is used. In recent years, as an apparatus of this kind, from the viewpoint of emphasizing throughput, a step-and-repeat reduction projection exposure apparatus (so-called “stepper”), a step-and-scan scanning exposure apparatus that improves this stepper, etc. The sequential movement type projection exposure apparatus is mainly used.

  In these exposure apparatuses, ultraviolet rays from an ultrahigh pressure mercury lamp, for example, i-line (wavelength 365 nm), KrF excimer laser light (wavelength 248 nm), etc. are used as illumination light (exposure beam) for exposure. In recent years, in order to obtain higher resolution (resolution), an exposure apparatus using ArF excimer laser light (wavelength 193 nm) as an exposure beam has been put into practical use. As the projection optical system of these exposure apparatuses, a refractive system or a catadioptric system has been mainly used.

  However, recently, in order to realize even higher resolution for these exposure apparatuses, a SOR (Synchrotron Orbital Radiation) ring or laser that generates extreme ultraviolet light (EUV (Extreme Ultraviolet) light) having a wavelength of 100 nm or less. Development of an EUV exposure apparatus (EUVL) using a plasma light source or the like as an exposure light source is underway.

  In an EUV exposure apparatus, since there is no optical material that can transmit EUV light at this time, the illumination optical system and the projection optical system are all-reflective optical systems composed of only reflective optical members (reflective optical elements). A reflective reticle is also used as the reticle. In addition, since EUV light is absorbed by almost all substances, the optical path space of the EUV light needs to be set to a predetermined high vacuum state, and the main body of the EUV exposure apparatus is usually installed in a vacuum chamber.

  However, like an EUV exposure apparatus, an all-reflection illumination optical system is used to make an exposure beam incident on a reflective reticle, and the reflected light from the reticle is incident on an all-reflection projection optical system and projected onto the wafer. In this case, since the object plane side (reticle side) of the projection optical system is non-telecentric, the position error of the reticle with respect to the optical axis direction of the projection optical system is the cause of the lateral shift of the image of the reticle pattern formed on the wafer. Become. When the reticle position error in the optical axis direction of the projection optical system is the same value, the lateral shift amount decreases as the incident angle of the exposure beam decreases. When manufacturing a highly integrated device having a minimum line width of about 70 nm or less, which is intended for an EUV exposure apparatus, the allowable total overlay error is very small, so that the numerical aperture (NA ) Is ensured, and the incident angle of the exposure beam is set small. For example, when the wavelength of the exposure beam is 13 nm, the incident angle of the exposure beam with respect to the reticle is set to about 50 [mrad] (see, for example, Patent Document 1 below). For this reason, from the viewpoint of preventing the exposure apparatus from becoming large, an illumination optical system and a projection optical system are arranged close to each other, and an unnecessary reflection optical element that directly leads from the illumination optical system to the reticle (that is, reduces exposure energy). In the case where the exposure beam is incident (without going through), a part of the mirror (hereinafter referred to as “specific mirror”) of the illumination optical system that makes the exposure beam incident on the reticle is placed almost directly below the reticle. It will be. However, normally, since the projection optical system is arranged directly under the reticle, it is necessary to install a specific mirror in the projection optical system or in the vicinity of the projection optical system.

  When the specific mirror is installed in the projection optical system or in the nearest position, the exposure beam is irradiated to the specific mirror, and the specific mirror adversely affects surrounding members due to the temperature rise caused by the heat absorption. There is a risk of giving. In particular, when a specific mirror is arranged inside the projection optical system, heat from the specific mirror is propagated mainly to the other optical members in the projection optical system through the lens barrel by heat conduction, Other optical members may be thermally deformed, and as a result, the imaging characteristics of the projection optical system may be deteriorated. Even when a specific mirror is installed at a position closest to the projection optical system and the reticle is irradiated with an exposure beam through a notch formed in a part of the lens barrel of the projection optical system, the mirror from the specific mirror is also used. Thermal deformation may occur in other optical members due to heat propagation through the cylinder.

  However, until now, as described above, since the refracting system or the catadioptric system has been mainly used as the projection optical system of the exposure apparatus, the optical element in the illumination optical system, like the above-described specific mirror, In fact, the configuration installed in the projection optical system or in the nearest vicinity of the projection optical system has hardly been considered.

  As can be seen from the above description, it is desirable that the position and angle of the reflecting surface of the specific mirror can be adjusted. The driving force of the mechanism or the reaction force thereof is transmitted to other optical elements in the projection optical system via the lens barrel, and may become a vibration factor of the other optical elements.

US Pat. No. 6,406,820

  The present invention has been made under the circumstances described above. From the first viewpoint, the photosensitive object (W) is exposed to illumination light (EL) through the reflective mask (R), and the reflective mask is used. An illumination optical system that includes a specific mirror (Mc) that causes illumination light to enter the reflective mask at a predetermined incident angle; A projection unit (PU) having a projection optical system that projects the illumination light emitted from the mold mask onto a photosensitive object; a body (26) that holds the projection unit; and the specific mirror that constitutes the illumination optical system And an illumination system holding stand (56) physically separated from the body.

  According to this, since the specific mirror is held by the illumination system holding gantry physically separated from the body holding the projection optical system, the specific mirror is arranged in the vicinity (or inside) of the projection unit. Nevertheless, even if the specific mirror generates heat (temperature rise) due to illumination light irradiation, the heat is prevented from propagating to the optical member constituting the projection optical system in the projection unit by heat conduction. . As a result, the optical performance (including the imaging characteristics) of the projection optical system due to thermal deformation of the optical member is effectively suppressed, and the projection optical system is used for a long period of time with high accuracy. Exposure (transfer of a pattern to a photosensitive object) can be realized.

  In this case, when the specific mirror is arranged in a lens barrel constituting the projection unit, the illumination light is incident on the specific mirror through an opening formed in the lens barrel, and the reflective mask. It can be reflected towards.

  Further, by performing exposure using the exposure apparatus of the present invention in the lithography process, the reflective mask pattern can be accurately transferred onto the photosensitive object over a long period of time, thereby increasing the degree of integration. The microdevice can be manufactured with high yield, and its productivity can be improved. Therefore, it can be said that the present invention is a device manufacturing method using the exposure apparatus of the present invention from the second viewpoint.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 schematically shows the overall configuration of an exposure apparatus 10 according to an embodiment. In FIG. 1, an upper chamber 42, a lower chamber 44, and a mirror chamber 40, which will be described later, constituting the exposure apparatus 10 are partially cut away.

  In this exposure apparatus 10, a projection unit PU that internally includes a projection optical system that projects a reflected light beam from the reticle R as a reflective mask onto a wafer W as a photosensitive object is employed. Refers to the projection direction of illumination light from the projection optical system onto the wafer W as the optical axis direction of the projection optical system, and this optical axis direction is the Z-axis direction, and the right and left sides in FIG. The direction is described as the Y-axis direction, and the direction orthogonal to the paper surface is described as the X-axis direction.

  The exposure apparatus 10 projects a partial image of a circuit pattern (hereinafter abbreviated as “reticle pattern”) formed on the reticle R onto the wafer W via the projection optical system in the projection unit PU. The reticle R and the wafer W are scanned in a one-dimensional direction (Y-axis direction) relative to the projection unit PU, so that the reticle pattern is applied to each of a plurality of shot areas on the wafer W in a step-and-scan manner. Transcript.

  The exposure apparatus 10 includes an illumination system 10A that illuminates the reticle R with illumination light (EUV light) EL, and an exposure apparatus body 10B that is disposed close to the + Y side of the illumination system 10A.

  The illumination system 10 </ b> A includes a first partial illumination system 12 and a second partial illumination system 15. Of these, the first partial illumination system 12 is shown as a simple block in FIG. 1 for convenience of illustration, but actually, as schematically shown in FIG. 3, a soft X-ray region having a wavelength of 11 nm. An exposure light source (not shown) composed of an SOR (Synchrotron Orbital Radiation) ring that emits an illumination light (EUV light) EL, a mirror system 114 including a condensing mirror, a collimator mirror, and the like, and a reflective optical A first fly-eye mirror 116A and a second fly-eye mirror 116B as an integrator (homogenizer) are provided. The illumination light EL is guided from an exposure light source (not shown) to a condenser mirror constituting the mirror system 114 via a beam line (not shown).

  For example, as shown in FIG. 4A, the first fly-eye mirror 116A includes a plurality of rows (three rows in FIG. 4A) of optical element groups 118A to 118C, and the optical element group 118A. Each of ˜118C includes a plurality of reflective optical elements (mirror elements) 120 each having an arc-shaped elongated reflecting surface. As shown in FIG. 4B, the second fly-eye mirror 116B includes a plurality of optical element groups 122A to 122C (three groups in FIG. 4B), and the optical element groups 122A to 122C. Each includes a plurality of reflecting optical elements (mirror elements) 123 having a substantially square reflecting surface. The optical elements constituting the optical element groups 122A to 122C are arranged so as to be approximately circular as a whole.

  In the first fly-eye mirror 116A and the second fly-eye mirror 116B, the optical element group 118A of the first fly-eye mirror 116A, the optical element group 122A of the second fly-eye mirror 116B, the optical element group 118B, and the optical element The element group 122B, the optical element group 118C, and the optical element group 122C correspond to each other. For example, as shown in FIG. 4C, the optical element group 118A is adjacent to the vertical direction in FIG. 4A. The light reflected by the three optical elements enters the three optical elements adjacent to the optical element group 122A in the left-right direction in FIG. 4B.

  In this case, the number of reflection optical elements arranged in the vertical direction on the paper surface of the first fly-eye mirror 116A is about three times the number of reflection optical elements arranged in the vertical direction on the paper surface of the second fly-eye mirror 116B. The illuminance on each reflective optical element of the second fly's eye mirror 116B is made uniform by the integration effect.

  Returning to FIG. 1, the second partial illumination system 15 sequentially reflects the illumination light EL emitted from the first partial illumination system 12 and finally reflects the illumination light EL of the reticle R at a predetermined incident angle, for example, about 50 [mrad]. A mirror unit 14 having a plurality of mirrors to be incident on the pattern surface (the lower surface in FIG. 1 (the surface on the −Z side)) and a mirror chamber 40 that houses the mirror unit 14 are provided.

  The mirror unit 14 is fixed on a support surface plate 50 supported substantially horizontally by a plurality (three or four in this case) of support members 52 provided on the floor surface F. The mirror chamber 40 described above is provided on the upper surface side of the support surface plate 50. A first opening 49 for allowing the illumination light EL from the first partial illumination system 12 to enter is formed on the −Y side wall of the mirror chamber 40, and the illumination light EL is applied to the + Y side wall of the mirror chamber 40. A second opening 48 for injection is formed.

  The mirror chamber 40 is highly airtight so that a high vacuum state such as a space defined by the mirror chamber 40 and the support surface plate 50 can be maintained.

  A part of the mirror unit 14 protrudes from the second opening 48 of the mirror chamber 40 that covers a predetermined space above the support member 52. As shown in FIGS. 2 and 3, the mirror unit 14 includes reflection mirrors (first reflection mirror Ma, second reflection mirror Mb, and third reflection mirror Mc) composed of three toroidal aspherical oblique incidence mirrors. And a holding base 60 for holding the three reflecting mirrors in a predetermined positional relationship. These reflecting mirrors Ma to Mc constitute a capacitor system. The mirror unit 14 will be described in detail later.

  In the present embodiment, the illumination optical system is configured by the above-described mirror system 114, the first fly-eye mirror 116A, the second fly-eye mirror 116B, and the first to third reflection mirrors Ma to Mc of the mirror unit 14. Has been.

  According to the illumination optical system configured as described above, the illumination light EL emitted from the exposure light source is collected by the condenser mirror constituting the mirror system 114, and reflected and deflected by the reflecting surface of the collimator mirror. As a result, the light becomes substantially parallel and enters the first fly-eye mirror 116A. The illumination light EL reflected by the first fly-eye mirror 116A is reflected by the second fly-eye mirror 116B and enters the first reflection mirror Ma constituting the mirror unit 14 in a state where the illuminance distribution is made uniform. . After that, the illumination light EL is sequentially reflected and collected by the first reflection mirror Ma, the second reflection mirror Mb, and the third reflection mirror Mc constituting the condenser system, and the pattern surface (lower surface) of the reticle R is formed into an arc slit shape. (In fact, the illumination light EL reaches the third reflection mirror Mc and the reticle R through the opening of the lens barrel of the projection unit PU described later (see FIG. 2)).

  As is clear from the above description, in the present embodiment, the specific mirror is configured by the third reflecting mirror Mc. Also, a plurality of support members 52 provided on the floor surface F, a support surface plate 50 supported horizontally by these support members, and the first to third reflection mirrors fixed on the support surface plate 50 An illumination system holding frame 56 is configured by the holding table 60 that holds Ma to Mc.

  As shown in FIGS. 1 and 2, the exposure apparatus main body 10B projects a reticle stage RST that holds the reticle R, and illumination light EL reflected by the pattern surface of the reticle R onto the exposed surface of the wafer W. A projection unit PU including a projection optical system, a wafer stage WST on which a wafer W is placed, a main body 26 as a body for holding the projection unit PU, and a lens barrel base plate (main frame) 20 constituting the body 26 The upper stage 42 that surrounds the remaining part of the reticle stage RST and the projection unit PU except for a part near the lower end of the projection unit PU, and is supported by being suspended from the lower surface of the lens barrel surface plate 20, and accommodates the wafer stage WST and the like. A lower chamber 44 is provided.

  As shown in FIGS. 1 and 2, the upper chamber 42 has a substantially rectangular parallelepiped shape, and has a projection unit PU, an alignment detection system ALG, a reticle stage RST, a reticle stage base 32, and a non-illustrated inside. The illustrated support column and the like are accommodated. An opening having substantially the same size and shape as the second opening 48 is formed in a part of the side wall on the −Y side of the upper chamber 42 (a part facing the second opening 48 formed in the mirror chamber 40). 47 is formed.

  Between the upper chamber 42 and the mirror chamber 40, an expandable / contractible bellows 46 that connects the chambers 42 and 40 is provided around the second opening 48 and the opening 47 described above. By this bellows 46, the internal space of the upper chamber 42 and the internal space of the mirror chamber 40 are separated from each other in an almost airtight state, and vibration transmission between the chambers 42 and 40 is suppressed.

  The upper chamber 42 is configured to be highly airtight so that a high vacuum state such as a space defined by the upper chamber 42 and the lens barrel surface plate 20 can be maintained.

  The reticle stage RST is disposed on a reticle stage base 32 that is horizontally supported by the aforementioned support column (not shown), and constitutes a reticle stage drive unit 34 (not shown in FIG. 1, see FIG. 11). It is levitated and supported on the reticle stage base 32 by a magnetic levitation force generated by a magnetic levitation type two-dimensional linear actuator. The reticle stage RST is driven with a predetermined stroke in the Y-axis direction by the driving force generated by the reticle stage drive unit 34, and is also driven in a minute amount in the X-axis direction and the θz direction (rotation direction around the Z axis). It has become. In addition, this reticle stage RST is adjusted by adjusting the magnetic levitation force generated at a plurality of locations by the reticle stage driving unit 34 in the Z-axis direction and the XY plane inclining directions (rotation directions around the X-axis, the θx direction and the Y-axis direction). It can also be driven by a minute amount in the rotation direction (θy direction).

  An electrostatic chuck type (or mechanical chuck type) reticle holder (not shown) is provided on the lower surface side of the reticle stage RST, and the reticle R is held by the reticle holder. As the reticle R, a reflective reticle is used in correspondence with the illumination light EL being EUV light having a wavelength of 11 nm. The reticle R is held by a reticle holder with the pattern surface being the lower surface. The reticle R is made of a thin plate such as a silicon wafer, quartz, or low expansion glass, and a reflective film that reflects EUV light is formed on the surface (pattern surface) on the −Z side. This reflective film is a multilayer film in which about 50 pairs of molybdenum Mo and beryllium Be films are alternately laminated with a period of about 5.5 nm. This multilayer film has a reflectance of about 70% for EUV light having a wavelength of 11 nm.

  On the multilayer film formed on the pattern surface of the reticle R, for example, nickel Ni or aluminum Al is applied on one surface as an absorption layer, and the absorption layer is patterned to form a circuit pattern.

  Illumination light (EUV light) EL that hits the portion of the reticle R where the absorption layer remains is absorbed by the absorption layer, and illumination that hits the reflection film in the portion where the absorption layer has been removed (portion from which the absorption layer has been removed) The light EL is reflected by the reflection film, and as a result, the illumination light EL including circuit pattern information travels toward the projection unit PU as reflected light from the pattern surface of the reticle R.

  The position of reticle stage RST (reticle R) in the stage movement plane (position in the XY plane) is a reticle laser interferometer (projecting a laser beam on a reflective surface provided (or formed) on reticle stage RST). Hereinafter, it is always detected by a resolution of about 0.5 to 1 nm, for example, by 82R) (reticle interferometer). Here, actually, the reticle interferometer is a reticle X interferometer that measures the X-axis direction position (X position) of the reticle stage RST and a reticle Y interference that measures the Y-axis direction position (Y position) of the reticle stage RST. In FIG. 1, these are typically shown as a reticle interferometer 82R. At least one of the reticle Y interferometer and the reticle X interferometer, for example, the reticle Y interferometer, is a two-axis interferometer having two measurement axes, and the reticle stage RST ( In addition to the Y position of reticle R), the rotation amount (yawing amount) in the θz direction (rotation direction about the Z axis) can also be measured.

  The position of the reticle R in the Z-axis direction and the tilt with respect to the XY plane (rotation amount in the θx and θy directions) are oblique to the pattern surface of the reticle R (a direction inclined at a predetermined angle with respect to the optical axis direction of the projection optical system). ) To irradiate a plurality of imaging light beams, and a light receiving system 13b having a plurality of light receiving elements for individually receiving the reflected light beams of the respective imaging light beams reflected by the pattern surface of the reticle R. It is measured (detected) by a reticle focus sensor (13a, 13b) comprising an oblique incidence type multi-point focal position detection system. A multi-point focal position detection system having the same configuration as the reticle focus sensor (13a, 13b) is disclosed in detail in, for example, Japanese Patent Laid-Open No. 6-283403 (corresponding US Pat. No. 5,448,332). .

  The measurement values of the reticle interferometer 82R and the reticle focus sensor (13a, 13b) are supplied to the main control device 120 (see FIG. 11), and the main control device 120 uses the reticle interferometer 82R and the reticle focus sensor (13a, 13b). The reticle stage RST is driven via the reticle stage drive unit 34 based on the measured value of (), so that the position and posture control of the reticle R in the six-dimensional direction is performed.

  As shown in FIG. 2, the main body 26 is provided on a plurality of (for example, three or four) support members 22 provided on the floor surface F, and one on each support member 22. A plurality of vibration isolation units 24, the lens barrel surface plate 20 supported substantially horizontally by the plurality of support members 22 via the vibration isolation units 24, and suspended from the lower surface of the lens barrel surface plate 20. The suspension column 43 fixed in a state and a support column (not shown) that is provided on the upper surface of the lens barrel surface plate 20 and supports the reticle stage base 32 described above.

  Each of the vibration isolation units 24 includes an air mount and a voice coil motor that are arranged in series (or in parallel) on the upper portion of the support member 22 and can adjust the internal pressure. By the air mount of each vibration isolation unit 24, the minute vibration from the floor surface F transmitted to the lens barrel surface plate 20 via the floor surface F and the support member 22 is insulated at the micro G level.

  The lens barrel surface plate 20 is made of a casting or the like, and is formed in a central portion of the first opening 20a that is circular in plan view (viewed from above) and at a position that is a predetermined distance away from the first opening 20a in the + X direction. And a second opening (not shown).

  The above-mentioned projection unit PU is inserted into the first opening 20a of the lens barrel base plate 20 from above, and three anti-vibration units provided on the lens barrel base plate 20 (located behind the projection unit PU). One anti-vibration unit (not shown) 28 supports the flange portion FLG1 of the projection unit PU at three points from below. As each vibration isolation unit 28, the thing of the structure similar to the above-mentioned vibration isolation unit 24 is used.

  As shown in FIG. 2, the projection unit PU includes a lens barrel 16 and a second mirror arranged in order from the top to the bottom within the lens barrel 16 in a predetermined positional relationship as shown in FIG. A projection optical system including a total of four mirrors (reflection optical elements), that is, M2, a fourth mirror M4, a third mirror M3, and a first mirror M1. This projection optical system has a numerical aperture (NA) of 0.1, for example, and a projection magnification of 1/4.

  Each of the first to fourth mirrors M1 to M4 has a reflection surface that is rotationally symmetric with respect to the optical axis of the projection unit PU (projection optical system), that is, the central axis of the lens barrel 16, and in particular, the first mirror M1. The reflecting surface of the fourth mirror M4 is a spherical surface. The unevenness error of each reflecting surface is suppressed to 0.2 nm to 0.3 nm or less in terms of RMS value (standard deviation) with respect to the design value. Further, the fourth mirror M4 has an opening as shown in FIG.

  Further, as can be seen from FIG. 2 and FIG. 5 showing the projection unit PU and the mirror unit 14 in a perspective view, the lens barrel 16 has an opening 59a on the −Y side of the peripheral wall, and through the opening 59a. Thus, the third reflection mirror Mc constituting the above-described mirror unit 14 is inserted inside the lens barrel 16. Further, as shown in FIG. 2, openings 59b and 59c serving as passages for the illumination light EL are formed in the upper wall (ceiling wall) and the bottom wall of the lens barrel 16.

  According to the projection unit PU configured in this way, as shown in FIG. 2, the illumination light EL sequentially reflected by the first reflection mirror Ma and the second reflection mirror Mb constituting the above-described capacitor system is mirrored. The light reaches the reflecting surface of the third reflecting mirror Mc via the second opening 48 of the chamber 40, the opening 47 of the upper chamber 42, and the opening 59a of the lens barrel 16 in order, and is reflected and collected by the reflecting surface. The light enters the pattern surface (lower surface) of the reticle R through the opening 59b of the cylinder 16 at a predetermined incident angle, for example, 50 (mrad). As a result, the pattern surface of the reticle R is illuminated by the illumination light EL having the arcuate slit shape.

  The illumination light EL including information on the reticle pattern reflected by the pattern surface of the reticle R enters the lens barrel 16 through the opening 59b and reaches the first mirror M1. The illumination light EL reflected by the reflecting surface of the first mirror M1 enters the reflecting surface of the second mirror M2 through the opening of the fourth mirror M4, is reflected by the reflecting surface, and passes through the opening of the fourth mirror M4. Through the reflecting surface of the third mirror M3. The illumination light EL reflected by the reflecting surface of the third mirror M3 is reflected by the reflecting surface of the fourth mirror M4, and the direction of the principal ray is deflected vertically downward. The illumination light EL is projected onto the wafer W. Thereby, a reduced image of the reticle pattern is formed on the wafer W.

  As shown in FIG. 1, the alignment detection system ALG is inserted from above into the second opening of the lens barrel surface plate 20, and the lens barrel surface plate is inserted through a flange FLG 2 provided on the outer periphery. 20 is fixed. As this alignment detection system ALG, FIA (Field Image Alignment) which irradiates an alignment mark (or an aerial image measuring device FM described later) on the wafer W with broadband light, receives the reflected light, and performs mark detection by image processing. LIA (Laser) which irradiates the diffraction grating-shaped alignment mark on the wafer W from two directions, causes the two generated diffracted lights to interfere, and detects the position information of the alignment mark from the phase. Interferometric Alignment (LSA) type alignment sensor, LSA (Laser Step Alignment) type alignment sensor or AFM that irradiates an alignment mark on the wafer W and measures the mark position using the intensity of diffracted and scattered light Use various types such as a scanning probe microscope such as (atomic force microscope). You can.

  Further, wafer focus sensors (104a, 104b) are integrally attached to the lens barrel 16 of the projection unit PU via a holding unit (not shown). The wafer focus sensors (104a, 104b) include an irradiation system 104a that irradiates a test surface (the surface of the wafer W) with a plurality of imaging light beams from a direction inclined by a predetermined angle with respect to the optical axis of the projection optical system; A multi-point focal position detection system having the same configuration as the above-described reticle focus sensor is used, which includes a light receiving system 104b having a plurality of light receiving elements that individually receive reflected light from the test surface of each imaging light beam. ing. The wafer focus sensor (104a, 104b) measures the position in the Z-axis direction and the tilt amount of the surface of the wafer W with reference to the lens barrel 16 of the projection unit PU.

  As shown in FIG. 2, the suspension column 43 includes a plurality of support members 45 each having one end connected to the lower surface of the lens barrel base plate 20, and the other ends of the plurality of support members 45. And a wafer stage base 30 that is connected and supported by the support members 45 so as to be horizontal below the lens barrel surface plate 20.

  Wafer stage WST is levitated and supported on wafer stage base 30 by a wafer stage driving unit 62 (not shown in FIGS. 1 and 2; see FIG. 11) made of, for example, a magnetic levitation type two-dimensional linear actuator. Wafer stage WST is driven by wafer stage drive unit 62 in the X-axis direction and Y-axis direction with a predetermined stroke (the stroke is, for example, 300 to 400 mm), and also in the θz direction (rotation direction about the Z-axis). A minute amount is driven. Wafer stage WST can be driven by wafer stage driving unit 62 by a minute amount in the Z-axis direction and in the tilt direction with respect to the XY plane.

  An electrostatic chuck type wafer holder (not shown) is placed on the upper surface of wafer stage WST, and wafer W is attracted and held by the wafer holder. The position of wafer stage WST is always detected by a wafer laser interferometer (hereinafter referred to as “wafer interferometer”) 82W arranged outside, for example, with a resolution of about 0.5 to 1 nm. In practice, an interferometer having a length measuring axis in the X-axis direction and an interferometer having a length measuring axis in the Y-axis direction are provided. In FIG. 1, these are typically shown as a wafer interferometer 82W. Has been. These interferometers are composed of multi-axis interferometers having a plurality of measurement axes, and in addition to the X and Y positions of wafer stage WST, rotation (yawing (θz rotation that is rotation around the Z axis)), pitching (X axis) Rotation around (θx rotation) and rolling (θy rotation around Y axis)) can also be measured.

  The measurement values of the wafer interferometer 82W and the wafer focus sensors (104a, 104b) are supplied to the main controller 120 (see FIG. 11), and the main controller 120 controls the wafer stage drive unit 62, so that the wafer stage WST Position and orientation control in a 6-dimensional direction is performed.

  At one end of the upper surface of wafer stage WST, measurement of the relative positional relationship between the position where the pattern formed on reticle R is projected onto wafer W and the alignment detection system ALG described later (so-called baseline measurement) is performed. An aerial image measuring instrument FM is provided. This aerial image measuring instrument FM corresponds to a reference mark plate of a conventional DUV exposure apparatus.

  A slit as an opening is formed on the upper surface of the aerial image measuring instrument FM. The slits are patterned on an EUV light reflecting layer formed on the surface of a fluorescent material having a predetermined thickness fixed to the upper surface of wafer stage WST. A photoelectric conversion element such as a photomultiplier is disposed inside wafer stage WST on the bottom side of the slit. With this arrangement, when the aerial image measuring instrument FM is irradiated with illumination light EL from above via the projection optical system, the illumination light EL transmitted through the slit reaches the fluorescence generating material, and this fluorescence generating material is converted into EUV light. It emits light with a longer wavelength. By receiving this light by the photoelectric conversion element and converting it into a detection signal corresponding to the intensity of the light, the projection position of the reticle pattern on wafer stage WST can be easily obtained. Instead of the reflective layer, an EUV light absorption layer may be provided, and a slit may be formed in the absorption layer.

  The lower chamber 44 has a substantially box-like shape with an open upper surface, and is fixed to the lower surface of the lens barrel surface plate 20 so as to surround the above-described suspension column 43 from below. The lower chamber 44 is configured to maintain a high vacuum state in a closed space defined by the lower chamber 44 and the lens barrel surface plate 20.

  In the exposure apparatus 10 of the present embodiment, the main barrel 120 is controlled by the main controller 120 based on the output of a vibration sensor SR1 (not shown in FIG. 1, see FIG. 11) that detects the vibration of the barrel base 20. Each anti-vibration unit 24 is controlled so as to cancel out the vibrations, and for example, a gap sensor SR2 (not shown in FIG. 1) that detects a gap (gap) between the lens barrel surface plate 20 and the support surface plate 50, for example. Based on the output of FIG. 11), each image stabilization unit 28 is controlled so that the gap becomes a desired value. For this reason, for example, the vibration generated in the lens barrel surface plate 20 when the wafer stage WST is driven is quickly attenuated and supported (held) by different frames (the body 26 and the illumination system holding frame 56). In addition, the positional relationship between the first to third reflecting mirrors Ma to Mc described above and the projection optical system in the projection unit PU can be always maintained in a desired positional relationship.

  Next, based on FIGS. 6-10, the structure of the said mirror unit 14, etc. are demonstrated in detail. Here, FIG. 6 shows a perspective view of the mirror unit 14.

  As shown in FIG. 6, the mirror unit 14 includes a holding base 60 fixed on the supporting surface plate 50 of FIG. 1 and a heat shielding mechanism 92 (see FIG. 8), three temperature control mechanisms 90a, 90b, 90c (see FIG. 9) provided at predetermined intervals on the heat shield mechanism 92, and temperature control mechanisms 90a, 90b, 90c, respectively. The above-described three reflection mirrors (first, second, and third reflection mirrors Ma, Mb, and Mc) are provided.

  As can be seen from FIG. 7 which shows the holding table 60 taken out, the holding table 60 includes a right side wall portion 124a, a left side wall portion 124b, and a back connecting portion 126 and a bottom portion for connecting the both side wall portions 124a and 124b. This is a structural member integrally formed as a whole having four portions with the connecting portion 128.

  The right side wall portion 124a has three slope portions (a first slope portion, a second slope portion, and a slope portion that gradually increases in inclination with respect to the XY plane from the front side (−Y side) to the rear side (+ Y side). 3rd slope part) is formed continuously. When the right side wall portion 124a is viewed from the side, the portion up to the second slope portion has a substantially trapezoidal shape. The left side wall part 124b has a symmetrical shape (symmetric with respect to the YZ plane) with the right side wall part 124a.

  Moreover, the right side wall part 124a, the left side wall part 124b, and the back surface connection part 126 are provided with openings in some places for weight reduction.

  The heat shield mechanism 92 is disposed between the left and right side wall portions 124a and 124b, as can be seen from FIG. 8 which is a perspective view with only the holding base 60 and the heat shield mechanism 92 taken out. The heat shield mechanism 92 has a plate-like shape that is bent substantially along the first slope portion, the second slope portion, and the third slope portion, and is formed at the front end of the bottom connecting portion 128. One end is locked at the one step higher part, and the rear connection part 126 is attached to the holding table 60 in a state where a part of the rear surface is supported by the upper end.

  As can be seen from FIG. 9 showing the state in which the reflection mirrors Ma to Mc are removed from the mirror unit 14 of FIG. 6, the first temperature adjustment mechanism 90a is a slope with the gentlest inclination angle on the foremost side of the heat shield mechanism 92. (Referred to as “first slope” for convenience). The third temperature adjustment mechanism 90c is fixed on the slope with the steepest inclination angle (called “third slope” for convenience) at the rearmost of the heat shield mechanism 92. Further, the second temperature adjustment mechanism 90b is fixed on a slope (referred to as a “second slope” for convenience) having the second smallest inclination angle between the first slope and the second slope of the heat shield mechanism 92. Has been. The specific configurations of the heat shield mechanism 92 and the first to third temperature control mechanisms 90a to 90c will be described in detail later.

  As shown in FIG. 6, the first reflection mirror Ma is disposed on the first temperature adjustment mechanism 90a, and the right side wall part 124a or the left side wall part 124b of the holding table 60 via the voice coil motors 86a to 86c. It is connected to the. The voice coil motors 86a and 86b are provided on the left side wall 124b side, and the voice coil motor 86c is provided on the right side wall 124a side. In each of the voice coil motors 86a to 86c, the stator is fixed to the holding base 60, and the mover is fixed to the first reflecting mirror Ma. Each of the voice coil motors 86a to 86c includes, for example, a stator formed of an armature unit including an armature coil and a mover formed of a magnetic pole unit including a permanent magnet, and the X-axis with respect to the first reflecting mirror Ma. By applying a driving force in the direction, the first reflecting mirror Ma is finely driven in the X-axis direction while being in contact with the first temperature adjustment mechanism 90a.

  The first reflection mirror Ma is made of a thin plate such as a silicon wafer, quartz, low expansion glass, and the like on the surface, like the mirror constituting the projection optical system in the projection unit PU described above. A reflective film for reflecting is formed. This reflective film is a multilayer film in which about 50 pairs of molybdenum Mo and beryllium Be films are alternately laminated with a period of about 5.5 nm. This multilayer film has a reflectance of about 70% for EUV light having a wavelength of 11 nm.

  The second reflection mirror Mb is disposed on the second temperature adjustment mechanism 90b, and is connected to the right side wall part 124a or the left side wall part 124b of the holding table 60 via voice coil motors 87a to 87c. The second reflecting mirror Mb can be finely driven in the X-axis direction while being in contact with the second temperature adjustment mechanism 90b by the driving force in the X-axis direction by the voice coil motors 87a to 87c. The second reflection mirror Mb is made of the same material as the first reflection mirror Ma, and the same reflection film is formed on the surface thereof.

  The third reflection mirror Mc is disposed on the third temperature adjustment mechanism 90c, and is connected to the right side wall part 124a or the left side wall part 124b of the holding table 60 via voice coil motors 88a to 88c. The third reflecting mirror Mc is moved in the X-axis direction in a state where the stator is in contact with the third temperature adjustment mechanism 90c by the driving force in the X-axis direction by the voice coil motors 88a to 88c fixed to the holding table 60. Small drive is possible. The third reflection mirror Mc is made of the same material as the first reflection mirror Ma, and the same reflection film is formed on the surface thereof.

  As is apparent from the above description, in this embodiment, the illumination system holding frame 56 is integrated with the first to third reflecting mirrors Ma to Mc by the voice coil motors 86a to 86c, 87a to 87c, and 88a to 88c. A holding / adjusting mechanism held by the holding table 60 is configured.

  FIG. 10 schematically shows the first to third reflecting mirrors (Ma to Mc), the first to third temperature control mechanisms (90a to 90c), and the heat shield mechanism 92 as viewed from the + X side. ing. As can be seen from FIG. 10, each of the first to third temperature adjustment mechanisms 90 a to 90 c is composed of, for example, a Peltier element. This Peltier element is a temperature control device that uses the Peltier effect, which is a phenomenon in which heat is generated or absorbed depending on the direction of current when a current flows through the contact surface of different types of metals. The first to third reflection mirrors Ma to Mc are cooled by supplying a predetermined current via the connected electrical wiring. The supply of current to the Peltier element is controlled by the main controller 120 based on, for example, the output of a temperature sensor SR3 (not shown in FIG. 10, refer to FIG. 11) provided on the back side of the mirror (see FIG. 11). Instead of the temperature sensor SR3, for example, the main control device 120 may predict a temperature change of the mirror, and may control the supply of current to the Peltier element according to the prediction result.

  As an example, the heat shield mechanism 92 includes a main body member 73 and a liquid pipe 72 laid over the entire inside of the main body member 73. In the heat shield mechanism 92, the cooling liquid is supplied from the liquid supply device 172 (see FIG. 11) to the liquid pipe 72, so that the temperature control mechanisms (Peltier elements) 90 a to 90 c and the heat shield mechanism 92 are interposed. Heat exchange is performed by heat conduction. Thereby, the back surface side of temperature control mechanism (Peltier device) 90a-90c is cooled, and the temperature rise is suppressed. In this case, the flow control of the cooling liquid of the liquid supply device 172 and the like are performed by the main control device 120 of FIG.

  In the mirror unit 14 configured in this way, even when the illumination light EL is incident upon the first to third reflection mirrors Ma to Mc and generates heat, the temperature control mechanisms (Peltier elements) 90a to 90c The first to third reflecting mirrors Ma to Mc can be cooled by the cooling function, and even if the back side of the Peltier elements 90a to 90c rises in temperature, the inside of the liquid pipe 72 of the heat shield mechanism 92 can be cooled. The liquid absorbs the heat and is discharged to the outside as a high-temperature liquid, so that the heat transfer to the periphery of the mirror unit 14 is substantially blocked.

  FIG. 11 shows the main configuration of the control system of the exposure apparatus 10 according to this embodiment. This control system is configured around a main control device 120 that performs overall control of the entire device.

  Next, the exposure operation by the exposure apparatus 10 according to the present embodiment configured as described above will be described.

  First, reticle R is transported by a reticle transport system (not shown), and is sucked and held on reticle stage RST at the loading position. Next, main controller 120 controls the positions of wafer stage WST and reticle stage RST, and a projection image of a reticle alignment mark (not shown) formed on reticle R onto the wafer W surface is an aerial image measuring device. The projection position of the reticle alignment mark on the wafer W surface is obtained by detection using FM. That is, reticle alignment is performed.

  Next, main controller 120 moves wafer stage WST so that aerial image detector FM is positioned directly below alignment detection system ALG, and the detection signal of alignment detection system ALG and the measurement of wafer interferometer 82W at that time are detected. Based on the position, the image forming position of the pattern image of the reticle R on the wafer W surface and the relative distance between the alignment detection system ALG, that is, the baseline distance is obtained indirectly.

  When the baseline measurement is completed, the main controller 120 performs wafer alignment (for example, EGA) and is defined by position information of all shot areas on the wafer W (for example, the measurement axis of the wafer interferometer). Position coordinates on the stage coordinate system).

  Then, under the control of the main controller 120, the scan start position (acceleration start position) for exposure of each shot area on the wafer W is used using the above-described baseline measurement result and wafer alignment result. An operation of moving the wafer stage WST and an operation of transferring a reticle pattern to the shot area by a scanning exposure method are alternately repeated. A step-and-scan exposure is a normal scanning stepper (scanner). The same is done.

  As described above in detail, according to the exposure apparatus 10 of the present embodiment, an illumination optical system including the third reflection mirror Mc as a specific mirror that causes the illumination light EL to enter the reticle R at a predetermined incident angle. The holding unit 60 that constitutes an illumination system holding stand 56 that is physically separated from the main body 26 that holds the projection unit PU and the like that project the illumination light EL emitted from the reticle R onto the wafer W. Is held by. For this reason, although the third reflection mirror Mc is disposed inside the lens barrel of the projection unit PU, heat (temperature rise) is generated on the third reflection mirror Mc due to irradiation of the illumination light EL. However, the heat is suppressed from being propagated by heat conduction to the optical members (mirrors M1 to M4) constituting the projection optical system in the projection unit PU. Thereby, it is possible to effectively suppress a decrease in optical performance (including imaging characteristics) of the projection optical system due to thermal deformation of the mirrors M1 to M4, and to use the projection optical system for a long time. Accurate exposure (reticle pattern transfer onto the wafer W) can be realized.

  In the present embodiment, a holding / adjusting mechanism including voice coil motors 86a to 86c, 87a to 87c, and 88a to 88c for driving the first reflecting mirror Ma, the second reflecting mirror Mb, and the third reflecting mirror Mc is provided. Therefore, the incident angle of the illumination light EL incident on the reticle R can be adjusted, and as a result, the exposure accuracy (superposition accuracy) can be maintained. Further, the mirror unit 14 including the holding / adjusting mechanisms (voice coil motors 86a to 86c, 87a to 87c, 88a to 88c) is a holding stand 60 that is physically separated from the main body 26 that supports the projection unit PU. Since the reaction force of the driving force of the first reflection mirror Ma, the second reflection mirror Mb, and the third reflection mirror Mc is not transmitted to the projection unit PU, the vibration factor of the projection unit is Never become. Similarly, even if floor vibrations are transmitted to the mirror unit 14, the vibrations are not transmitted to the projection unit PU.

  In the present embodiment, the first, second, and third reflecting mirrors Ma, Mb, and Mc are provided with temperature control mechanisms (Peltier elements) 90a, 90b, and 90c on the back side, so The influence of the heat generated by the third reflecting mirror Mc on the peripheral members due to the illumination light EL entering the third reflecting mirror Ma, Mb, Mc can be suppressed as much as possible.

  Furthermore, in this embodiment, since the temperature control mechanism (Peltier element) 90a, 90b, 90c is provided with the heat shield mechanism 92 on the opposite side to the first, second, and third reflection mirrors Ma, Mb, Mc. The heat generated on the back side of the Peltier element due to the cooling of the first, second, and third reflection mirrors Ma, Mb, and Mc by the Peltier element can be suppressed from being transmitted to the peripheral members. .

  Furthermore, according to the exposure apparatus 10 of the present embodiment, the pattern of the reticle R is transferred onto the wafer W via the all-reflection projection unit PU having no chromatic aberration using the illumination light EL having an extremely short wavelength as the exposure light. The fine pattern on the reticle R can be transferred to each shot area on the wafer W with high accuracy. Specifically, a fine pattern with a minimum line width of about 70 nm can be transferred with high accuracy.

  In the above-described embodiment, the case where the third reflecting mirror Mc as the specific mirror is disposed in the projection unit PU has been described. However, the present invention is not limited to this, and the predetermined angle with respect to the reticle R is used. If EUV light can be incident, a specific mirror may be disposed outside the projection unit.

  In the above embodiment, the case where the mirror unit 14 has three reflecting mirrors has been described. However, the present invention is not limited to this, and the EUV light emitted from the light source can be guided to the reticle R. Any number of reflection mirrors may be used.

  In the above embodiment, each of the reflection mirrors constituting the mirror unit is provided with a voice coil motor (drive mechanism), a Peltier element as a temperature control mechanism, and a heat exchanger as a heat shut-off mechanism. The invention is not limited to this, and at least one of a drive mechanism, a Peltier element, and a heat exchange mechanism may be provided in at least one of the reflection mirrors. Moreover, it is good also as not providing all the drive mechanisms, a Peltier device, and a heat exchange mechanism in all the reflective mirrors.

  In the above embodiment, the bellows is provided between the mirror chamber 40 and the upper chamber 42. However, the present invention is not limited to this, and the heat generated in the specific mirror in the projection unit PU is not limited to this. From the viewpoint of suppressing transmission to the mirror, the bellows is not necessarily provided.

  In the above-described embodiment, the case where the main body 26 includes the vibration isolation unit has been described. However, the present invention is not limited to this, and for example, the floor surface F and the support member 52 are also provided on the illumination system holding stand 56 side. An anti-vibration unit may be provided to insulate vibrations from the floor surface F transmitted to the support surface plate 50 via the micro G level. As the vibration isolation unit in this case, a passive vibration isolation unit may be employed, or an active vibration isolation unit having the same configuration as that of the vibration isolation unit 24 described above may be employed.

  Moreover, in the said embodiment, although the mirror unit 14 is comprised by the three reflection mirrors, this invention is not limited to this, The illumination light which injected into the mirror unit 14 from the light source has a predetermined incident angle. So long as it can enter the reticle R. Accordingly, the number of mirrors can be arbitrarily set.

In the above embodiment, the case where EUV light is used as the exposure light and the all-reflection projection optical system including only four mirrors is used has been described as an example, and the present invention is not limited thereto. Of course. That is, for example, an exposure apparatus having a projection optical system composed of only six mirrors, as well as a VUV light source having a wavelength of 100 to 160 nm, for example, an Ar ₂ laser (wavelength 126 nm) as a light source, and 4 to 8 mirrors. A projection optical system having the same can also be used. The projection optical system may be either a refractive projection optical system consisting only of a lens or a catadioptric projection optical system including a lens in part.

  In the above embodiment, the case where EUV light having a wavelength of 11 nm is used as exposure light has been described. However, the present invention is not limited to this, and EUV light having a wavelength of 13 nm may be used as exposure light. In this case, in order to secure a reflectance of about 70% with respect to EUV light having a wavelength of 13 nm, it is necessary to use a multilayer film in which molybdenum Mo and silicon Si are alternately laminated as the reflection film of each mirror.

  In the above embodiment, SOR (Synchrotron Orbital Radiation) is used as an exposure light source. Also good.

<Device manufacturing method>
Next, an embodiment of a device manufacturing method using the above-described exposure apparatus in a lithography process will be described.

  FIG. 12 shows a flowchart of a manufacturing example of a device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micromachine, etc.). As shown in FIG. 12, first, in step 201 (design step), device function / performance design (for example, circuit design of a semiconductor device) is performed, and pattern design for realizing the function is performed. Subsequently, in step 202 (mask manufacturing step), a mask on which the designed circuit pattern is formed is manufactured. On the other hand, in step 203 (wafer manufacturing step), a wafer is manufactured using a material such as silicon.

  Next, in step 204 (wafer processing step), using the mask and wafer prepared in steps 201 to 203, an actual circuit or the like is formed on the wafer by lithography or the like as will be described later. Next, in step 205 (device assembly step), device assembly is performed using the wafer processed in step 204. Step 205 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary.

  Finally, in step 206 (inspection step), inspections such as an operation confirmation test and durability test of the device created in step 205 are performed. After these steps, the device is completed and shipped.

  FIG. 13 shows a detailed flow example of step 204 in the semiconductor device. In FIG. 13, in step 211 (oxidation step), the surface of the wafer is oxidized. In step 212 (CVD step), an insulating film is formed on the wafer surface. In step 213 (electrode formation step), an electrode is formed on the wafer by vapor deposition. In step 214 (ion implantation step), ions are implanted into the wafer. Each of the above-described steps 211 to 214 constitutes a pre-processing process at each stage of wafer processing, and is selected and executed according to a necessary process at each stage.

  At each stage of the wafer process, when the above pre-process is completed, the post-process is executed as follows. In this post-processing process, first, in step 215 (resist formation step), a photosensitive agent is applied to the wafer. Subsequently, in step 216 (exposure step), the circuit pattern of the mask is transferred to the wafer by the exposure apparatus 10 described above. Next, in step 217 (development step), the exposed wafer is developed, and in step 218 (etching step), the exposed members other than the portion where the resist remains are removed by etching. In step 219 (resist removal step), the resist that has become unnecessary after the etching is removed.

  By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the wafer.

  If the device manufacturing method of the present embodiment described above is used, the exposure apparatus of the above-described embodiment is used in the exposure step (step 216), so that deterioration of pattern fidelity in the transfer image of the pattern formed on the wafer is ignored. It is possible to suppress the image blur as a whole as much as possible and to transfer the pattern with a desired line width. Therefore, it is possible to manufacture an electronic device having a good line width uniformity of a pattern in a chip, and as a result, it is possible to improve the productivity (including yield) of an electronic device having a high degree of integration.

  The exposure apparatus of the present invention is suitable for exposing a photosensitive object with illumination light through a reflective mask and transferring a pattern formed on the reflective mask onto the photosensitive object. The device manufacturing method of the present invention is suitable for manufacturing devices such as semiconductor elements.

It is a figure which shows schematic structure of the exposure apparatus which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view which shows the exposure apparatus of FIG. It is a figure which shows the structure of an illumination system. 4A is a diagram showing the first fly-eye mirror 116A in FIG. 3, and FIG. 4B is a diagram showing the second fly-eye mirror 116B in FIG. 3, and FIG. () Is a figure for demonstrating the effect | action of both fly-eye mirrors. It is a perspective view which shows the projection unit and mirror unit of FIG. It is a perspective view which shows the mirror unit of FIG. It is a perspective view which shows the holding stand which comprises the mirror unit of FIG. It is a perspective view which shows the state in which the heat shield mechanism was provided in the holding stand of FIG. It is a perspective view which shows the state which removed the reflective mirrors Ma-Mc with the voice coil motor from the mirror unit of FIG. FIG. 3 is a schematic view in the X direction of a reflection mirror that constitutes a mirror unit. It is a block diagram which shows the control system of one Embodiment. It is a flowchart for demonstrating embodiment of the device manufacturing method which concerns on this invention. It is a flowchart which shows the detail of step 204 of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus, 26 ... Main body (body), 56 ... Illumination system holding stand, 86a-88c ... Voice coil motor (holding / adjusting mechanism), 90a-90c ... Temperature control mechanism, 92 ... Heat shut-off mechanism), EL ... EUV light (illumination light), Mc ... third reflection mirror (specific mirror), PU ... projection unit, R ... reticle (reflection mask), W ... wafer (photosensitive object).

Claims (8)

An exposure apparatus that exposes a photosensitive object with illumination light through a reflective mask and transfers a pattern formed on the reflective mask onto the photosensitive object,
An illumination optical system including a specific mirror that causes illumination light to enter the reflective mask at a predetermined incident angle;
A projection unit having a projection optical system that projects the illumination light emitted from the reflective mask onto a photosensitive object;
A body holding the projection unit;
An exposure apparatus comprising: an illumination system holding gantry that holds a plurality of optical members including the specific mirror constituting the illumination optical system and is physically separated from the body. The specific mirror is arranged in a lens barrel constituting the projection unit,
The exposure apparatus according to claim 1, wherein the illumination light is incident on the specific mirror through an opening formed in the lens barrel and is reflected toward the reflective mask.   The exposure apparatus according to claim 1, further comprising a holding / adjusting mechanism that is held on the illumination system holding frame integrally with the plurality of optical members.   The exposure apparatus according to any one of claims 1 to 3, further comprising a temperature control mechanism that is integrally held by the illumination system holding frame with the plurality of optical members.   The exposure apparatus according to any one of claims 1 to 4, further comprising a heat shut-off mechanism that is integrally held by the illumination system holding frame with the plurality of optical members.   6. The exposure apparatus according to claim 1, wherein both the illumination optical system and the projection optical system are reflection optical systems.   The exposure apparatus according to claim 1, wherein the illumination light is extreme ultraviolet light. A device manufacturing method including a lithography process,
A device manufacturing method comprising exposing a photosensitive object using the exposure apparatus according to claim 1 in the lithography step.

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