JP2007242707A - Measuring apparatus, pattern forming device and lithography device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure face information on a wafer surface without being affected by thickness (uniformity) and a dielectric ratio of resist. <P>SOLUTION: Since a capacitance sensor 54 measures position information on an upper face of a floating object 48 floating by an amount corresponding to moving speed of the wafer from the surface (upper face) of a wafer by dynamic pressure of air flow generated by movement of the wafer W, face information of the wafer surface can indirectly be measured without directly measuring the wafer surface. Thus, face information on the wafer W surface can be measured without being affected by thickness (uniformity) and the dielectric ratio of resist even if resist is applied onto the wafer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a measurement apparatus, a pattern formation apparatus, and a lithography apparatus, and more particularly to a measurement apparatus that measures the surface shape of an object, a pattern formation apparatus that includes the measurement apparatus, and a lithography apparatus.

  Conventionally, in a lithography process for manufacturing semiconductor elements, liquid crystal display elements, etc., a step-and-repeat type static projection exposure apparatus (so-called stepper) and a step-and-scan type scanning projection exposure apparatus (so-called scanning). Projection exposure apparatuses such as steppers are mainly used.

  In this type of projection exposure apparatus, in order to accurately transfer a pattern onto a substrate such as a wafer, the surface of the exposed area of the substrate matches the best imaging surface of the projection optical system (the depth of focus of the projection optical system). It is necessary to transfer the pattern onto the substrate in a state in which the pattern is matched within the range (1). For this purpose, it is necessary to accurately measure the position of the substrate surface with respect to the optical axis direction of the projection optical system. Conventionally, a projection exposure apparatus is usually equipped with a device for that purpose (focal position detection system). .

  In particular, recent exposure apparatuses are usually equipped with a multipoint focal position detection system in which a plurality of measurement points are set within the field of view of the projection optical system (see, for example, Patent Document 1). According to this multi-point focal position detection system, position information (surface information) in the optical axis direction of the projection optical system can be detected at a plurality of points on the substrate surface. Can also be detected.

  However, this multi-point focal position detection system is very large in size, and it is necessary to keep a large space in order to arrange it near the substrate. In addition, since the multipoint focus position detection system is greatly affected by air fluctuations, it is necessary to strictly manage the air conditioning in the vicinity thereof.

  On the other hand, the size of other gap sensors such as a capacitance sensor can be reduced as compared with the multipoint focal position detection system.

  However, in measurement by a gap sensor such as a capacitance sensor, the measurement result may be greatly affected by the surface physical properties of the object to be measured. That is, using this gap sensor, when measuring surface information of a substrate coated with a photosensitive agent (resist) on the surface, the measurement result is greatly influenced by the resist thickness (uniformity), dielectric constant, etc. There is a risk that the measurement accuracy may decrease.

Japanese Patent Laid-Open No. 2004-253401

  The present invention has been made under the circumstances described above. From a first viewpoint, the present invention is a measuring device that measures surface information of a predetermined surface of an object, and is disposed on the predetermined surface side of the object, and the object A levitating body that floats by an amount corresponding to the moving speed of the object from a predetermined surface of the object by the dynamic pressure of the air flow generated by the movement of the levitating body in a predetermined moving direction; A measuring device that measures position information of a surface opposite to the surface.

  According to this, the surface information of the predetermined surface of the object can be indirectly measured without directly measuring the predetermined surface of the object. For this reason, it becomes possible to measure the surface information of the predetermined surface of the object with high accuracy without being affected by the physical properties of the object and the surface state of the predetermined surface.

  According to a second aspect of the present invention, there is provided a pattern forming apparatus for forming a pattern on an object, the driving apparatus driving the object; and while the object is moving in the moving direction by the driving apparatus. A pattern forming apparatus comprising: a measuring device according to the present invention that measures surface information of a predetermined surface of the object; and a pattern forming unit that forms a pattern on the object in consideration of a measurement result of the measuring device.

  According to this, surface information of an object driven by a driving device is measured using a measuring device capable of measuring surface information of a predetermined surface of an object with high accuracy, and the measurement result is taken into consideration. Since the pattern is formed on the object in the pattern forming unit, the pattern can be formed on the object with high accuracy.

  According to a third aspect of the present invention, there is provided a drive device that drives an object; and a measurement device according to the present invention that measures surface information of a predetermined surface of the object, based on a measurement result of the measurement device. A lithographic apparatus for driving the object.

  According to this, surface information of an object driven by a driving device is measured using a measuring device capable of measuring surface information of a predetermined surface of an object with high accuracy, and the measurement result is taken into consideration. Since the object is driven, it is possible to perform a predetermined process on the object with high accuracy.

  FIG. 1 schematically shows a configuration of an exposure apparatus 100 according to an embodiment of the present invention. The exposure apparatus 100 is a step-and-scan type scanning exposure apparatus, that is, a so-called scanner.

  The exposure apparatus 100 holds the reticle R illuminated by the illumination system 10 and the exposure light (illumination light) IL from the illumination system 10 and holds a predetermined scanning direction (here, Y in the left-right direction in FIG. 1). Reticle stage RST moving in the axial direction), projection optical system PL for projecting exposure light (illumination light) IL emitted from reticle R onto wafer W, wafer stage WST on which wafer W is placed, wafer W Including a surface information measuring device 50 for measuring the surface information of these, and a control system thereof.

  The illumination system 10 includes a light source and an illumination optical system. As the light source, for example, an ArF excimer laser light source (output wavelength: 193 nm) is used. The illumination optical system includes, for example, a beam shaping optical system, an energy coarse adjuster, an optical integrator (a uniformizer or a homogenizer), an illumination system aperture stop plate, a beam splitter, and a relay lens arranged in a predetermined positional relationship. , A reticle blind, a mirror for bending an optical path, a condenser lens (all not shown), and the like. The configuration of the illumination system 10 and the function of each optical member are disclosed in, for example, the pamphlet of International Publication No. 2002/103766, and therefore detailed description thereof is omitted here.

  On reticle stage RST, reticle R on which a circuit pattern or the like is formed on its pattern surface (lower surface in FIG. 1) is fixed, for example, by vacuum suction. The reticle stage RST can be driven minutely in the XY plane by a reticle stage drive system 11 including a linear motor, for example, and can be driven at a scanning speed specified in the scanning direction (Y-axis direction).

  The position of the reticle stage RST in the stage moving surface (including rotation around the Z axis) is moved by a reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 16 in a moving mirror 15 (actually in the Y axis direction). Through a Y movable mirror having a perpendicular reflecting surface and an X moving mirror (or a retroreflector etc.) having a reflecting surface perpendicular to the X-axis direction) with a resolution of about 0.5 to 1 nm, for example. Always detected. The measurement value of the reticle interferometer 16 is sent to the main controller 20, and the main controller 20 uses the measurement value of the reticle interferometer 16 to drive the reticle stage RST in the X-axis direction via the reticle stage drive system 11. The position (and speed) in the Y-axis direction and the θz direction (the rotation direction around the Z-axis) are controlled.

  The projection optical system PL is disposed below the reticle stage RST in FIG. 1, and a lens barrel fixing member constituting a body BD disposed on a floor surface (or a base plate or the like) via a vibration isolation mechanism (not shown). It is supported by the board 38 via its flange FLG.

  Projection optical system PL is configured to include a lens barrel and a plurality of optical elements held in a predetermined positional relationship in the lens barrel. As the plurality of optical elements, for example, a refractive optical system including a plurality of lenses (lens elements) having a common optical axis AX in the Z-axis direction is used. The projection optical system PL is, for example, both-side telecentric and has a predetermined projection magnification (for example, 1/4, 1/5, or 1/8). The projection optical system is not limited to a refractive optical system, and for example, a catadioptric system may be used.

  Although not shown, an alignment detection system is disposed on the side surface of the projection optical system PL. In the present embodiment, an imaging type alignment sensor that detects street lines and position detection marks (fine alignment marks) formed on the wafer W is used as an alignment detection system. The detailed configuration of this alignment detection system is disclosed in, for example, Japanese Patent Laid-Open No. 9-219354. The detection result by the alignment detection system is supplied to the main controller 20.

  Wafer stage WST is arranged on a base board 71 arranged on a floor surface (or a base plate or the like) via a vibration isolation mechanism (not shown). On the bottom surface of wafer stage WST, non-contact bearings (not shown), for example, air bearings (also referred to as air pads) are provided at a plurality of locations. With these air bearings, wafer stage WST is placed on upper surface 71a of base board 71. On the other hand, it is levitated and supported through a clearance of about several μm. On wafer stage WST, wafer holder 70 for holding wafer W by vacuum suction or the like is provided.

  Wafer stage WST is driven by stage drive system 27 in the XY plane (including θz rotation) and in the Z-axis direction, θx, and θy directions. Note that the stage drive system 27 includes, for example, a linear motor (or a planar motor).

  The position information of wafer stage WST is, for example, 0 by a wafer laser interferometer (hereinafter referred to as “wafer interferometer”) 18 that irradiates a length measuring beam onto a reflection surface formed by mirror processing of the end surface (side surface) of wafer stage WST. It is always detected with a resolution of about 5 to 1 nm. At least a part of the wafer interferometer 18 is supported in a suspended state from the lens barrel surface plate 38.

More specifically, as shown in FIG. 2, the −X side surface of the wafer stage WST is actually the reflecting surface 17X, and the −Y side surface is the reflecting surface 17Y. Laser interferometers 18X ₁ and 18X ₂ for measuring the X-axis direction position and a laser interferometer 18Y for measuring the Y-axis direction position are provided. When wafer stage WST is at a position (for example, exposure position) indicated by a solid line in FIG. 2, measurement is performed by laser interferometers 18X ₁ and 18Y, and wafer stage WST is at a position indicated by a virtual line in FIG. When it is at the indicated position (for example, a measurement position), it is measured by the laser interferometers 18X ₂ and 18Y. Among these, at least one of the laser interferometer for measuring the position in the X-axis direction and the laser interferometer for measuring the position in the Y-axis direction is a multi-axis interferometer having a plurality of measurement axes, and the X and Y positions of the wafer stage WST. In addition, rotation (including at least rotation (yawing) in the θz direction) can be measured.

  A multi-axis interferometer is used as both the laser interferometer for measuring the X-axis direction position and the laser interferometer for measuring the Y-axis direction position. In addition to yawing, pitching (rotation in the θx direction), rolling (θy direction) (Rotation) may also be measured.

  In the present embodiment, as shown in FIG. 1, a reflecting mirror 17Z having a reflecting surface inclined by 45 ° with respect to the XY plane is provided in the lower half portion of the end surface of wafer stage WST. 17Z is irradiated with a measurement beam in a direction parallel to the XY plane from the wafer interferometer 18. This length measurement beam is reflected by the reflecting mirror 17Z and irradiated to a fixed mirror (not shown) made of a plane mirror having a reflecting surface parallel to the XY plane fixed to the lower surface (−Z side surface) of the lens barrel surface plate 38. After being reflected by the fixed mirror, it is reflected again by the reflecting surface of the reflecting mirror 17Z and returns to the wafer interferometer 18. Wafer interferometer 18 receives this return light beam and measures it as Z position information of wafer stage WST. Here, in reality, reflecting mirrors are provided on each of the −X side surface and the −Y side surface of wafer stage WST, and the length measurement beams are irradiated to each of two locations of each reflecting mirror. In addition to the position of wafer stage WST in the Z-axis direction, interferometer 18 tilts in the Y direction (inclination (rotation) in the θx direction with respect to the XY plane, that is, the aforementioned pitching), tilt in the X direction (inclination in the θy direction with respect to the XY plane ( Rotation), that is, the aforementioned rolling) can also be measured.

  When pitching (rotation in the θx direction) and rolling (rotation in the θy direction) can be measured using the reflection surfaces 17X and 17Y, only the Z direction may be measured in the measurement using the reflection mirror 17Z. good.

  The position information (or speed information) of wafer stage WST described above is sent to main controller 20. Main controller 20 controls the position of wafer stage WST in the 6-degree-of-freedom direction via wafer stage drive system 27 based on the position information (or speed information) of wafer stage WST.

  The surface information measuring device 50 is fixed to the lower surface of the lens barrel surface plate 38, as shown in FIG. As shown in the perspective view of FIG. 3, the surface information measuring device 50 includes a large number of sensor mechanisms (sensor units or sensor modules) SR1, SR2, SR3,... Arranged along the X-axis direction. .

  Each of these sensor mechanisms includes a base 44 fixed to the lower surface of the lens barrel surface plate 38 and a lower surface of the base 44, as can be seen from FIG. A leaf spring 46 having a substantially inverted Z shape when viewed from the + X direction to the -X direction, a floating body 48 secured to the lower end of the leaf spring 46, and the floating body A capacitance sensor 54 is provided on the lower surface of the base 44 so as to face the upper surface of the 48, and measures a gap with the upper surface of the floating body 48.

  Further, the sensor mechanism SR1 includes a holding mechanism 52 for holding the floating body at a predetermined height (predetermined Z position). The holding mechanism 52 includes an electromagnet mechanism 52a including a coil fixed to the lower surface of the base 44, and a magnetic member fixed to the upper surface of the floating body 48 at a position facing the electromagnet mechanism 52a in the Z-axis direction. 52b. According to the holding mechanism 52, when an electric current is supplied to the coil constituting the electromagnet mechanism 52a, a magnetic attractive force is generated between the electromagnet mechanism 52a and the magnetic member 52b as shown in FIG. As shown in FIG. 4B, when the floating body 48 is held at a predetermined height, while the supply of current to the coils constituting the electromagnet mechanism 52a is stopped. In addition, the magnetic attractive force (holding force for holding the floating body 48) is released, and the floating body 48 moves downward (down) due to its own weight.

  The levitation body 48 is made of, for example, stainless steel, and when the wafer W is in contact with the surface of the wafer W as shown in FIG. When it moves, as shown in FIG. 4C, it floats by a predetermined distance (referred to as distance L) by the dynamic pressure of the air flow generated by the movement of the wafer W. Note that a chamfered portion 48 a is provided at the −Y side end of the lower surface (−Z side surface) of the floating body 48, whereby an air flow is formed between the upper surface of the wafer W and the lower surface of the floating body 48. It is easy to be done.

  According to the sensor mechanism SR1 configured as described above, when the wafer W moves at a predetermined speed, the levitated body 48 is lifted by a distance corresponding to the speed. Therefore, by maintaining the speed at, for example, the speed V, the wafer W It is possible to keep the distance between the levitation body 48 and the floating body 48 constant (L). Therefore, since the height position (Z-axis direction position) of the floating body 48 changes according to the unevenness on the surface of the wafer, by measuring the position of the upper surface of the floating body 48 using the capacitance sensor 54, In particular, position information on the surface of the wafer W can be measured.

  Returning to FIG. 3, the other sensor mechanisms SR2, SR3,... In the following, for convenience of explanation, even when explanation is given using the sensor mechanisms SR2, SR3,... When the width of the floating body 48 of each sensor mechanism in the X-axis direction is, for example, 5 mm and the wafer W has a diameter of 300 mm, about 60 sensor mechanisms are arranged along the X-axis direction. become.

  In the surface information measuring apparatus 50 of the present embodiment configured as described above, the distribution of the Z position information on the surface of the wafer is measured in the procedure as shown in FIGS. 5 (A) to 6 (C). Prior to this measurement, in order to detect a measurement error between the sensor mechanisms, for example, a substrate with a guaranteed flatness (such as a super flat wafer) is placed on the wafer holder 70, and the surface information measuring device 50 performs the measurement. It is good also as performing calibration between each electrostatic capacitance sensor using the measurement result of a board | substrate. At this time, by using the tilt information of the wafer stage WST by the wafer interferometer 18 (tilt in the X and Y directions described above), for example, the calibration substrate is set parallel to the XY plane before the measurement, or the measurement result May be corrected. Further, the measurement value (Z position information) of the wafer interferometer 18 and the measurement value of each sensor mechanism are associated with each other.

  In FIG. 5A, the exposure of the wafer placed on wafer stage WST is completed, and the wafer replacement position (in this example, the exposed wafer is unloaded from wafer stage WST and the next exposure target is set). The wafer stage WST is positioned at a position where a certain wafer W is loaded onto the wafer stage WST, and a new wafer W is loaded. In this state, as can be seen from FIG. 5A, the wafer W and the floating body 48 constituting each sensor mechanism are not opposed to each other. In this state, current is supplied to the magnetic body mechanism 52a (coil) of the holding mechanism 52 of each sensor mechanism, and the height of the floating body 48 of each sensor mechanism is the height shown in FIG. Is set to

From this state, main controller 20 moves wafer stage WST at a constant speed V in the + Y direction at a constant speed by wafer stage drive system 27 based on the measurement results of laser interferometers 18X ₂ and 18Y. Then, the wafer W and the floating body 48 of a part of the sensor mechanisms face each other (in FIG. 5B, the sensor mechanism facing the wafer W among the plurality of sensor mechanisms is shown in black). Thus, main controller 20 releases the magnetic attractive force (holding force) of holding mechanism 52 constituting these sensor mechanisms. Here, the holding of the floating body 48 by the holding mechanism 52 is released when the plurality of floating bodies 48 face the wafer W. However, the present invention is not limited to this, and the floating body 48 facing the wafer W is not limited thereto. The holding may be released in order. Further, for example, when the wafer W is placed on the wafer stage WST so that the surface thereof substantially coincides with the surface of the wafer W, the holding of all the floating bodies is simultaneously released after facing the wafer stage WST. Alternatively, the holding may be canceled in order from the floating body arranged near the center. At this time, release of the holding of the floating body 48 may be performed at the time of facing the wafer W, or may be performed immediately before that.

  By releasing the holding force as described above, the floating bodies 48 of those sensor mechanisms try to move from the state of FIG. 4A to the state of FIG. Since it is moving at a constant velocity V, the floating body 48 is kept floating by a predetermined distance L with respect to the wafer W due to the dynamic pressure of the airflow generated between the lower surface of the floating body 48 and the upper surface of the wafer W. (See FIG. 4C).

Here, main controller 20 detects the gap between the upper surface of floating body 48 and capacitance sensor 54 using the sensor mechanism shown in black in FIG. Then, main controller 20 maps the detection result in association with the values of interferometers 18X ₂ and 18Y.

  Thereafter, as shown in FIG. 5C, as the wafer stage WST moves in the + Y direction, the number of sensor mechanisms facing the wafer W increases. The holding force of the holding mechanism 52 is released. During this time, measurement using each sensor mechanism is performed at a predetermined sampling interval.

  In this way, main controller 20 increases the number of sensor mechanisms to be measured while wafer stage WST moves to the position shown in FIG. After the state of FIG. 6 (A), as shown in FIGS. 6 (B) and 6 (C), the number of sensor mechanisms that do not face the wafer W gradually increases. Supply of current to the holding mechanism 52 (coil of the electromagnet mechanism 52a) of the sensor mechanism (or the sensor mechanism just before facing the wafer W) that is no longer opposed to the wafer W is started, and the floating body 48 that constitutes the sensor mechanism is started. Is held at a predetermined height (the height shown in FIG. 4A).

  As described above, when the measurement (mapping) over almost the entire surface of the wafer W is completed, the measurement of the distribution of the Z position information on the surface of the wafer W is completed.

  Here, the measurement result of the electrostatic capacity sensor 54 indicates that the attitude of the wafer stage WST (the position in the Z-axis direction and the inclination in the θy (rotation around the Y axis) direction (or the inclination in the θx (rotation around the X axis) direction). )). Therefore, in this embodiment, each measurement result is corrected based on the measurement value of the interferometer 18 at the time of the measurement. That is, the distribution of the Z position information on the wafer surface is measured in consideration of the variation factor that fluctuates the measurement result by the capacitance sensor 54.

Thereafter, main controller 20 moves wafer stage WST to an alignment position (just below an alignment system not shown) for aligning wafer W. Incidentally, during this movement, the measurement beam from the interferometer 18X ₂ can not impinge on the reflecting surface of the wafer stage WST, main controller 20, the interferometer 18X ₂ interferometer 18X ₁ and at the same time the wafer stage WST The interferometer is connected in the same manner as in the prior art while it is in contact with the reflecting surface.

  Then, main controller 20 uses EGA (enhanced global alignment) disclosed in, for example, Japanese Patent Laid-Open No. 61-44429, using an alignment system (not shown) in a state where wafer stage WST is at the alignment position. Thereafter, an exposure operation by the step-and-scan method is performed on the wafer W on the wafer stage WST.

  In the present embodiment, main controller 20 controls the position / posture of wafer stage WST in the Z-axis direction based on the measurement result by surface information measuring device 50 described above during the exposure operation. In other words, the projection optical system uses the distribution of the Z position information on the surface of the wafer W measured by the surface information measuring device 50 and the measurement value of the wafer interferometer 18 (including Z position information, pitching, and rolling in this example). In the exposure area IA where the pattern image of the reticle is projected within the field of view of the system PL, the exposed area of the wafer W matches the best imaging plane of the projection optical system PL (within the range of the focal depth of the projection optical system PL). Wafer stage WST is controlled so as to match. Note that the best imaging plane of the projection optical system PL can be measured using an aerial image measuring instrument or the like provided on the wafer stage WST, for example, before performing the exposure operation. In this example, the best imaging plane is measured in association with the measurement value (Z position information, etc.) of the wafer interferometer 18.

  Then, at the stage where the exposure for all shot areas on wafer W is completed, main controller 20 moves wafer stage WST to the position shown in FIG. 6A again, unloads wafer W, and creates a new wafer. After the loading, the measurement of the Z position information distribution of the new wafer, the alignment operation, and the exposure operation are sequentially executed in the same manner as described above.

  As described above in detail, according to the surface shape measuring apparatus 50 of this embodiment, the moving speed of the wafer W from the surface (upper surface) of the wafer W due to the dynamic pressure of the airflow generated by the movement of the wafer W in the Y-axis direction. Since the electrostatic sensor 54 measures the position information of the upper surface of the floating body 48 that floats by an amount corresponding to the surface information, the surface information of the wafer surface is indirectly measured without directly measuring the wafer surface. be able to. For this reason, even when a resist is applied on the wafer W, the surface information on the surface of the wafer W can be measured without being affected by the thickness (uniformity) of the resist or the dielectric constant. Is possible.

  Further, according to the exposure apparatus 100 of the present embodiment, the wafer is being moved by the wafer stage WST using the surface shape measuring apparatus 50 capable of measuring the surface information of the wafer surface with high accuracy as described above. Since surface information of W is measured and exposure (pattern formation on the wafer) is performed by controlling the driving of wafer stage WST based on the measurement result, exposure (pattern formation) on wafer W is performed with high accuracy. Is possible.

  In the present embodiment, since the holding mechanism 52 that holds the floating body 48 at a predetermined height is provided in each sensor mechanism, the wafer W and the floating body are in a state where the wafer W and the floating body 48 do not face each other. It is possible to avoid contact between the wafer peripheral portion (edge portion) and the levitated body 48 (mechanically interfere) while the two are opposed to each other. Further, particularly when the wafer W is placed on the wafer stage WST so that the surface thereof substantially coincides with the surface of the wafer W, by releasing the holding after the floating body 48 faces the wafer stage WST, Contact between wafer stage WST and floating body 48 can also be avoided.

  Further, in the present embodiment, since a capacitance sensor is used, the size can be reduced as compared with a conventional multipoint focal position detection system. As a result, it is possible to reduce the overall size of the exposure apparatus, and in turn reduce the footprint.

  In the above embodiment, the wafer surface information is measured prior to the exposure of the wafer W. However, the present invention is not limited to this, and a sensor mechanism is provided in the vicinity of the exposure area IA of the projection optical system PL. The surface information of the wafer may be measured in parallel with at least a part of the exposure operation of the wafer W. In this case, the sensor mechanism can be used as a prefetch sensor. Further, in the above embodiment, as shown in FIG. 5A, when the wafer stage WST is disposed at the wafer exchange position, the surface information measuring device 50 so that each sensor mechanism (the floating body 48) faces the wafer stage WST. However, the present invention is not limited to this. For example, the surface information measuring device 50 is provided in the vicinity of the above-described alignment detection system, and is parallel to at least a part of the detection operation of the alignment mark of the wafer by the alignment detection system. Thus, the wafer surface information may be measured. Further, for example, between a wafer exchange position and a position (measurement position) where mark detection is performed by the alignment detection system, or a measurement position and a position (a reticle pattern image is transferred via the projection optical system PL). The surface information measuring device 50 may be provided on the wafer movement path between the exposure position and the surface information may be measured while the wafer is moving between the two positions. In the above embodiment, when measuring the wafer surface information, the wafer is moved along the direction (Y direction) orthogonal to the arrangement direction (X direction) of the sensor mechanism. However, the present invention is not limited to this. The wafer may be moved in a direction different from both the arrangement direction of the sensor mechanisms and the direction orthogonal thereto. In the above embodiment, the wafer loading and unloading are performed at the same position. However, the present invention is not limited to this, and the loading position and the unloading position may be different. In this case, it is preferable that the wafer exchange position is a load position.

  In the above embodiment, each sensor mechanism (floating body 48) of the surface information measuring device 50 is disposed close to the wafer. For example, all the sensor mechanisms are integrally fixed to the holding member, or a large number of sensor mechanisms. Are individually or separately divided and supported in a suspended state from the lens barrel surface plate. For this reason, for example, a measurement error may occur between the sensor mechanisms of the surface information measuring device 50 due to expansion and contraction of the support portion of the sensor mechanism due to temperature change, heat transfer, or the like. Therefore, for example, by providing a heat insulating member between the lens barrel base plate and the support portion of the sensor mechanism, or by providing a mechanism for adjusting the temperature of the support portion, expansion / contraction of the support portion can be prevented (suppressed). preferable. Alternatively, for example, it is preferable to measure the temperature of the support portion of the sensor mechanism or its surroundings, and calibrate the surface information measuring device 50 (for example, set the offset of the sensor mechanism) using the measurement result.

  Further, in the above embodiment, the position and orientation (tilt) in the Z direction of wafer stage WST are controlled based on the measurement result of surface information measuring device 50. However, the present invention is not limited to this, but instead. Alternatively, or in combination therewith, for example, the position and inclination of the imaging plane (pattern image) of the projection optical system PL are changed by at least one of the movement of the optical element of the projection optical system PL and the movement of the reticle R. good.

  In the above embodiment, the capacitance sensor is used as a measuring instrument for measuring the displacement (positional information) of the levitated body. However, the present invention is not limited to this, and the measuring instrument may be an optical sensor, for example. It is also possible to adopt.

  In the above embodiment, a plurality of sensor mechanisms are provided in a row along the X-axis direction. However, the present invention is not limited to this, and in a direction intersecting the Y-axis direction in a horizontal plane other than the X-axis direction. A plurality of arrangements may be provided in a row, or a plurality of arrangements may be performed without forming a row, for example, in a state of being distributed in at least a direction other than the Y-axis direction (so as not to overlap in the Y-axis direction). It is also good to do. Moreover, it is good also as providing not only when providing a plurality of sensor mechanisms but only one. Furthermore, a plurality of detection units having a plurality of sensor mechanisms with different positions in the X-axis direction may be provided apart in the Y-axis direction. In this case, the position of the sensor mechanism in the X-axis direction may be different among the plurality of detection units.

  In the above embodiment, the holding mechanism 52 uses a magnetic attractive force. However, the holding mechanism 52 is not limited to this. For example, electrostatic adsorption or vacuum adsorption may be used, or a mechanical mechanism may be used. Etc. may be used.

  In the above embodiment, the sensor mechanism is provided with the holding mechanism 52 that holds the floating body 48 at a predetermined height when the floating body 48 does not face the wafer W. For example, when the upper surface of wafer stage WST and the surface of wafer W are set flat (for example, when the wafer holder is embedded in wafer stage WST), the floating body is held at a predetermined height. In some cases, the peripheral portion (edge portion) of the wafer W and the floating body 48 may not mechanically interfere (not contact). In such a case, the holding mechanism 52 may not be provided in the sensor mechanism. good.

  In the above embodiment, the interferometer is used to measure the position of the wafer W in the Z direction and the amount of rotation in the θy direction. However, the present invention is not limited to this. For example, sensors at both ends of a sensor mechanism forming a row The mechanism may be used to measure two height positions (displacements) of wafer stage WST, and to measure the position of wafer W in the Z direction and the amount of rotation in the θy direction based on the measurement result.

  In the above embodiment, the wafer alignment operation is performed after the distribution of the Z position information on the surface of the wafer W is measured. However, the present invention is not limited to this, and the distribution of the Z position information on the surface of the wafer W is measured. The wafer alignment operation may be performed before, or both operations may be performed in parallel. Note that performing both operations in parallel can be realized, for example, by moving the alignment system in synchronization with wafer stage WST.

  In the above embodiment, the case where only one wafer stage WST is provided has been described. However, the present invention is not limited to this, and a twin stage type stage device including two wafer stages can be adopted. It is also possible to employ a stage apparatus including a wafer stage and a measurement stage as disclosed in the publication No. 2005/074014 pamphlet. In a twin stage type stage apparatus, the wafer surface is detected using the above-mentioned surface information measuring device or the mark detection of the wafer on the other wafer stage in the time during the exposure operation for the wafer on one wafer stage. Therefore, it is possible to improve the throughput. When a measurement stage is provided, various measurements can be performed during the time between wafer exchange and wafer surface information measurement on the wafer stage side. It is possible to improve throughput, and it is not necessary to mount a measuring device on the wafer stage side, so that the wafer stage can be made smaller and lighter and the positioning accuracy of the wafer stage can be improved accordingly. It becomes possible.

  Note that the present invention can also be applied to an immersion exposure apparatus disclosed in International Publication No. 2004/53955 pamphlet. Further, as disclosed in International Publication No. 2001/035168, an exposure apparatus that forms line and space patterns on a wafer by forming interference fringes on the wafer using a diffraction grating. The present invention can also be applied. Further, for example, as disclosed in JP-T-2004-51850, two reticle patterns are synthesized on a wafer via a projection optical system, and one shot area on the wafer is obtained by one scan exposure. The present invention can also be applied to an exposure apparatus that performs double exposure almost simultaneously.

  Further, the projection optical system in the exposure apparatus of the above embodiment may be not only a reduction system but also an equal magnification system or an enlargement system, and the projection optical system PL may be not only a refraction system but also a reflection system or a catadioptric system, The projected image may be an inverted image or an erect image. Further, the exposure light source is not limited to the excimer laser, and may be, for example, a DFB semiconductor laser or fiber laser harmonic generator disclosed in International Publication No. 99/46835 pamphlet, or a mercury lamp.

  In the above-described embodiment, the case where the present invention is applied to a scanning exposure apparatus such as a step-and-scan method has been described, but it is needless to say that the scope of the present invention is not limited to this. That is, the present invention can be suitably applied to a step-and-repeat reduction projection exposure apparatus. Furthermore, the present invention can be applied to a proximity type exposure apparatus, a mirror projection aligner, an X-ray exposure apparatus, an EUV exposure apparatus, an exposure apparatus using a charged particle beam such as an electron beam or an ion beam, and the like. .

  In the above embodiment, a light transmissive mask (reticle) in which a predetermined light shielding pattern (or phase pattern / dimming pattern) is formed on a light transmissive substrate is used. Instead of this reticle, for example, As disclosed in US Pat. No. 6,778,257, an electronic mask (variable molding mask) that forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed is disclosed. It may be used. The exposure apparatus is not limited to an exposure apparatus for manufacturing a semiconductor. For example, an exposure apparatus for liquid crystal that transfers a liquid crystal display element pattern to a square glass plate, an organic EL, a thin film magnetic head, and an image sensor. The present invention can be widely applied to exposure apparatuses for manufacturing (CCD, etc.), micromachines, and DNA chips. Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., glass substrates or silicon wafers, etc. The present invention can also be applied to an exposure apparatus that transfers a circuit pattern.

  In the above embodiment, the case where the surface information measuring device 50 is provided in the exposure apparatus 100 has been described. However, the pattern forming apparatus that forms a pattern on an object is not limited to the above-described exposure apparatus (lithography apparatus). However, for example, as disclosed in Japanese Patent Application Laid-Open No. 2003-80694, a functional film is formed by applying a liquid onto a substrate having a film formation surface using an inkjet nozzle, and the applied liquid is subjected to heat treatment. The surface information measuring device 50 may be provided in the pattern forming apparatus that executes the process of converting to a liquid crystal, and the liquid may be applied onto the substrate by inkjet in consideration of the measurement result of the surface information measuring device.

  Further, the surface information measuring device 50 of the above embodiment can be provided not only in the exposure apparatus and the pattern forming apparatus but also in a lithography apparatus including an inspection apparatus for inspecting the wafer W after completion of exposure, for example. In this lithographic apparatus (device manufacturing apparatus), for example, using a measurement result obtained by the surface information measuring apparatus 50, a driving apparatus that drives a wafer provided in the inspection apparatus can be controlled.

  Furthermore, the object (measurement target) whose surface information is to be measured in the above embodiment is not limited to the wafer, but may be another object such as a glass plate, a ceramic substrate, or mask blanks.

  The semiconductor device was formed on the reticle by the step of designing the function / performance of the device, the step of manufacturing a reticle based on this design step, the step of manufacturing a wafer from a silicon material, and the exposure method of the above embodiment. It is manufactured through a lithography step for transferring a pattern onto an object such as a wafer, a device assembly step (including a dicing process, a bonding process, and a packaging process), an inspection step, and the like. In this case, in the lithography step, the exposure method of the above embodiment is executed, and a device pattern is formed on the object. Therefore, it is possible to improve the productivity of a highly integrated device.

  As described above, the measurement apparatus of the present invention is suitable for measuring surface information of a predetermined surface of an object. The pattern forming apparatus of the present invention is suitable for forming a pattern on an object. The lithographic apparatus of the present invention is suitable for performing various processes including a lithography process.

It is the schematic which shows the exposure apparatus which concerns on one Embodiment. It is a figure for demonstrating the structure and interferometer arrangement | positioning of wafer stage WST. It is a perspective view which shows the schematic structure of a surface information measuring device. FIG. 4A to FIG. 4B are diagrams for explaining the configuration and function of the sensor mechanism. FIG. 5A to FIG. 5C are views (No. 1) for explaining a measurement method by the surface information measurement apparatus. FIG. 6A to FIG. 6C are diagrams (No. 2) for explaining a measurement method by the surface information measurement device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 18 ... Laser interferometer (position information measuring device), 20 ... Main control device (calculation device), 27 ... Wafer stage driving system (part of driving device), 48 ... Floating body, 50 ... Surface information measuring device (measuring device) ), 52... Holding mechanism, 54... Capacitance sensor (measuring instrument), 100... Exposure apparatus (pattern forming apparatus), W .wafer (object), WST.

Claims (16)

A measuring device that measures surface information of a predetermined surface of an object,
A levitating body that is disposed on a predetermined surface side of the object and floats from the predetermined surface of the object by an amount corresponding to the moving speed of the object by dynamic pressure of an air flow generated by movement of the object in a predetermined movement direction; ;
A measuring instrument that measures position information of a surface of the levitating body opposite to the surface facing the object.   The measurement apparatus according to claim 1, further comprising a calculation apparatus that calculates the surface information from a measurement result obtained by the measurement instrument.   The measurement apparatus according to claim 2, wherein the calculation apparatus calculates the surface information in consideration of a variation factor that varies a measurement result obtained by the measuring instrument.   The measuring device according to claim 1, wherein the measuring instrument is a capacitance sensor.   The measuring apparatus according to claim 1, wherein the measuring instrument is an optical sensor. A plurality of the floating bodies are distributed and arranged in at least a direction other than the moving direction of the object,
The measuring apparatus according to claim 1, wherein a plurality of the measuring instruments are provided corresponding to the floating body.   The measuring apparatus according to claim 1, further comprising a holding mechanism that holds the floating body at a predetermined height in a state where the floating body does not face the object.   The measuring device according to claim 1, wherein the measuring device measures position information in a direction perpendicular to a plane including the moving direction.   The measuring apparatus according to claim 1, wherein a photosensitive agent is applied to a predetermined surface of the object. A pattern forming apparatus for forming a pattern on an object,
A driving device for driving the object;
The measuring device according to any one of claims 1 to 9, wherein surface information of a predetermined surface of the object is measured while the object is moving in the moving direction by the driving device.
A pattern forming unit configured to form a pattern on the object in consideration of a measurement result of the measurement device.   The pattern forming apparatus according to claim 10, wherein the driving apparatus drives the object in consideration of a measurement result of the measuring apparatus when the pattern forming unit forms a pattern on the object. . When the pattern forming unit forms a pattern on the object, the pattern forming unit further includes a position information measuring device that measures position information of the object,
The pattern forming apparatus according to claim 11, wherein the driving apparatus drives the object further considering a measurement result of the position information measuring apparatus.   The pattern forming apparatus according to claim 10, wherein the measurement by the measuring apparatus is performed before the pattern forming unit starts forming a pattern on the object.   The pattern forming apparatus according to claim 10, wherein the measurement by the measuring apparatus is performed in parallel with forming a pattern on the object in the pattern forming unit.   The pattern forming apparatus according to claim 10, wherein the pattern forming unit exposes the object to form a pattern. A driving device for driving an object;
Measuring the surface information of the predetermined surface of the object, and the measuring device according to any one of claims 1 to 9,
A lithography apparatus, wherein the object is driven based on a measurement result of the measurement apparatus.

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