JP2002313697A - Observing device, position detecting device, aligner, and manufacturing method for microdevice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aligner having a position detecting device which can easily detect a mark at a different position with high precision. SOLUTION: This aligner is equipped with a projection optical system 4 which protects an image of a transfer pattern formed on a reticle 3 on a photosensitive substrate 5, and position detecting devices 61R and 61L which detect the position of a mark formed on the reticle. The position detecting devices are equipped with detection optical systems 22R and 23R1, and 22L and 23L1 which converge light from the mark; photoelectric detecting elements 22Ra and 22La which photoelectrically detect the light passed through the optical systems; and optical path switching means 24R and 24L which perform switching to one of a 1st optical path guiding the light from the mark at a 1st position to the detection optical systems, and a 2nd optical path guiding the light from the mark at a 2nd position different from the 1st position to the detection optical systems, while fixing the focus positions of the detection optical systems so as to selectively observe the mark at the 1st position and the mark at the 2nd position on an observation surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an observation apparatus for observing an object to be observed, a position detection apparatus for detecting a position of a mark, an exposure apparatus having the position detection apparatus, and a method for manufacturing a micro device using the exposure apparatus. It is about.

[0002]

2. Description of the Related Art Conventionally, various exposure apparatuses have been used in a lithography process for manufacturing micro devices such as semiconductor elements and liquid crystal display elements. In recent years, for example, as a semiconductor exposure apparatus, a photomask or a reticle (hereinafter, referred to as a “reticle”) has been used.
It is called a reticle. Step-and-repeat, which transfers the fine pattern formed in step (1) onto a substrate (hereinafter, referred to as a wafer) such as a semiconductor wafer or a glass plate coated with a photosensitive agent such as a photoresist via a projection optical system. A projection exposure apparatus such as a reduced projection exposure apparatus of a system (so-called stepper) and a step-and-scan type scanning projection exposure apparatus (a so-called scanning stepper) obtained by improving the stepper are mainly used.

[0003] In the case of manufacturing a semiconductor device or the like, it is necessary to form different circuit patterns on the wafer in a number of layers, so that a reticle on which the circuit pattern is drawn and each shot area on the wafer are already provided. It is important that the formed pattern be exactly overlapped. The required accuracy of the alignment between the reticle and the wafer is becoming stricter as the pattern becomes finer.
Various ideas have been devised for the alignment.

The detection of the position of a wafer by a stepper or the like
This is performed by detecting an alignment mark (alignment mark) formed on the wafer. As a method of detecting the alignment mark, for example, irradiation with light having a wide wavelength bandwidth using a halogen lamp or the like as a light source,
An FIA (Field Im) that measures the position of the mark by performing image processing on the image data of the alignment mark captured by a camera or the like.
age-alignment-based off-axis alignment sensors and the like are known. According to the FIA-based alignment sensor, the position of an aluminum mark, an asymmetric mark, or the like can be detected with high accuracy without being affected by thin film interference caused by the resist layer.

[0005] Similarly, the position of the reticle is detected by detecting a positioning mark (alignment mark) formed on the reticle. In this case, a device using exposure light as a detection light beam is generally used. It is a target. For example, a VRA (Visual Reticle Alignment) type sensor that irradiates exposure light onto an alignment mark formed on a reticle and processes the image data of the alignment mark captured by a CCD camera or the like to measure the mark position is known. ing.

Further, the alignment mark formed on the wafer and the alignment mark formed on the reticle are irradiated with illumination light for alignment, and simultaneously imaged by a CCD camera or the like, and the relative distance between the two marks in a plane is measured. A TTR (Through the reticle) sensor that measures a positional relationship is also used.

The alignment between the reticle and the wafer using these optical alignment sensors is performed by controlling the relative positional relationship between the reticle (reticle stage) and the wafer (wafer stage) based on the detection result of the alignment mark. The exposure is performed in a step-and-repeat method or a step-and-scan method, so that a reticle pattern is sequentially superimposed and transferred onto each shot area on the wafer.

[0008]

Incidentally, the position of the alignment mark formed on the reticle may differ depending on the type of the reticle. FIG. 14 is a diagram for explaining a method of observing an alignment mark by a conventional detection optical system, that is, a method of observing an alignment mark arranged at a different position. As shown in this figure, conventionally, when observing alignment marks (AM1, AM2) arranged at different positions on the reticle R with one detection optical system, the first objective lens 100 and a mirror for epi-illumination are used. The observation of the alignment mark AM1 or the alignment mark AM2 is performed by moving the unit 102 integrally.

However, the alignment marks (A) arranged at different positions on the reticle R by the above-described method.
When observing (M1, AM2), it is necessary to move the position of the first objective lens 100 extremely precisely so as not to cause eccentricity, and further, to prevent the focus position of the detection optical system from changing. In addition, it is necessary to move the first objective lens 100 and the mirror 102 for epi-illumination integrally with high precision.

An object of the present invention is to provide an observation device capable of easily and accurately changing an observation position, a position detection device capable of easily and accurately detecting a mark at a different position, and this position detection device. And a method for manufacturing a micro device using the exposure apparatus.

[0011]

According to a first aspect of the present invention, there is provided an observation apparatus comprising: a detection optical system for condensing light from an object to be observed; a photoelectric detection element for photoelectrically detecting light passing through the detection optical system;
In order to selectively observe a first position and a second position different from the first position on the observation surface on which the object to be observed is installed, the focus position of the detection optical system is made invariable while maintaining the focus position. An optical path switching means for switching between a first optical path for guiding light from a first position to the detection optical system and a second optical path for guiding light from the second position to the detection optical system; It is characterized by having.

According to the first aspect, the light from the first position is guided to the detection optical system while the focus position of the detection optical system remains unchanged by the optical path switching means.
Can be switched between the first optical path and the second optical path for guiding light from the second position to the detection optical system, so that a plurality of objects to be observed can be easily and highly accurately observed by the detection optical system.

According to a second aspect of the present invention, in the observation apparatus, the optical path switching means is provided with a first optical path deflecting means for forming the first optical path, and the second optical path deflecting means is provided interchangeably with the first optical path deflecting means. A second optical path deflecting means for forming an optical path, wherein the optical path length of the first optical path in the first optical path deflecting means and the optical path length of the second optical path in the second optical path deflecting means. The optical path lengths are equal to each other.

According to the second aspect of the present invention, the optical path length of the first optical path in the first optical path deflecting means and the second optical path length are different from each other.
Since the optical path lengths of the second optical path in the optical path deflecting unit are equal to each other, the light from the first position is detected via the first optical path deflecting unit while the focus position of the detection optical system remains unchanged. Guides the light from the second position to the second
The light can be guided to the detection optical system via the optical path deflecting means.

According to a third aspect of the present invention, the first optical path deflecting means includes a first prism forming the first optical path, and the second optical path deflecting means forms the second optical path. It is characterized by including a second prism.

According to a fourth aspect of the present invention, in the observation apparatus, the first optical path deflecting means includes at least two surface reflection mirrors forming the first optical path, and the second optical path deflecting means includes the second optical path. Wherein at least two surface reflecting mirrors are formed.

According to a fifth aspect of the present invention, there is provided a position detecting device for detecting a position of an object to be observed, a detection optical system for condensing light from a mark formed on the object to be observed, and the detection optical system. A photoelectric detection element for photoelectrically detecting light passing through the system,
In order to selectively observe a mark at a first position and a mark at a second position different from the first position on the observation surface on which the object to be observed is installed, the focus position of the detection optical system is changed. Either a first optical path for guiding the light from the mark at the first position to the detection optical system while maintaining the same or a second optical path for guiding the light from the mark at the second position to the detection optical system. And an optical path switching means for switching between the two.

According to the position detecting device of the fifth aspect, the first optical path for guiding the light from the mark at the first position to the detecting optical system while keeping the focus position of the detecting optical system unchanged by the optical path switching means. And the second optical path for guiding the light from the mark at the second position to the detection optical system can be switched, so that the positions of the plurality of marks can be easily and accurately detected by the detection optical system.

Further, in the position detecting device according to the present invention, the optical path switching means may be a first optical path deflecting means for forming the first optical path and the second optical path deflecting means may be interchangeably provided with the first optical path deflecting means. Second optical path deflecting means for forming an optical path of
The optical path length of the first light path in the first path deflecting means is equal to the optical path length of the second light path in the second path deflecting means.

According to the position detecting device of the sixth aspect, the optical path length of the first optical path in the first optical path deflecting means and the optical path length of the second optical path in the second optical path deflecting means. Since the lengths are equal to each other, the light from the mark at the first position is guided to the detection optical system via the first optical path deflecting unit while the focus position of the detection optical system remains unchanged, and the light from the mark at the second position is Can be guided to the detection optical system via the second optical path deflecting means.

According to a seventh aspect of the present invention, in the position detecting device, the first optical path deflecting means includes a first prism forming the first optical path, and the second optical path deflecting means forms the second optical path. And a second prism.

Further, in the position detecting device according to the present invention, the first optical path deflecting means includes at least two surface reflection mirrors forming the first optical path, and the second optical path deflecting means includes the second optical path deflecting means. It is characterized by including at least two surface reflection mirrors forming an optical path.

According to a ninth aspect of the present invention, there is provided an exposure apparatus, comprising: a projection optical system for projecting an image of a transfer pattern formed on a reticle onto a photosensitive substrate; and a relative alignment between the reticle and the photosensitive substrate. The apparatus according to any one of claims 5 to 8, further comprising a position detecting device configured to detect one of the reticle and the photosensitive substrate as the object to be observed. .

According to the ninth aspect of the present invention, since the position detecting device can accurately detect the position of either the reticle or the photosensitive substrate as an object to be observed, the reticle and the photosensitive substrate can be accurately detected. Relative positioning can be performed very accurately.

According to a tenth aspect of the present invention, there is provided a method of manufacturing a micro device, comprising the steps of: exposing a transfer pattern of a reticle onto a photosensitive substrate using the exposure apparatus of the ninth aspect; And a developing step of developing the photosensitive substrate.

According to the method of manufacturing a micro device according to the tenth aspect, since the image of the transfer pattern formed on the reticle can be faithfully formed on the photosensitive substrate, the micro device can be manufactured with high throughput. be able to.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A projection exposure apparatus according to a first embodiment of the present invention, that is, a step-and-scan type projection exposure apparatus as a scanning exposure type will be described below with reference to the drawings. Do.

FIG. 1 is a partially cutaway front view showing the projection exposure apparatus according to the first embodiment. This figure 1
In exposure, illumination light (exposure light) IL for exposure is emitted from an exposure light source system 1 at the time of exposure, and the emitted exposure light IL passes through an illumination system 2 and has an elongated rectangular illumination area on a pattern forming surface (lower surface) of a reticle 3. 63 (see FIG. 3) is illuminated with a uniform illuminance distribution.

The exposure light source system 1 is composed of an exposure light source, a variable light amount unit, a light beam shaping unit, and the like. As the exposure light source, KrF (oscillation wavelength 248 nm), ArF (oscillation wavelength 193 nm) or F2 laser (oscillation wavelength) is used. 157n
m) and other excimer laser light sources, solid-state laser light sources, YAG
A laser harmonic generator or a mercury lamp can be used. The illumination system 2 includes a fly-eye lens, an optical integrator (homogenizer) such as an internal reflection type glass rod or a diffractive optical element, an aperture stop (σ stop), a relay optical system, a field stop (reticle blind), and a condenser lens system. The shape of the illumination area 63 on the reticle 3 is defined by the field stop.

In FIG. 1, at the time of exposure, the projection optical system 4
The wafer (photosensitive substrate) 5 on which a photoresist as a substrate is applied moves to the exposure region of FIG. And the exposure light I
Under L, the pattern in the illumination area of the reticle 3 is projected through the projection optical system 4 to a projection magnification β (β is 1/4, 1/5, etc.).
Is projected on the wafer 5. The wafer 5 is made of, for example, a semiconductor (such as silicon) or SOI (silicon on insu).
lator).

Hereinafter, Z is set parallel to the optical axis AX of the projection optical system 4.
An axis will be described, and an X axis will be taken parallel to the plane of FIG. 1 and a Y axis will be taken perpendicular to the plane of FIG. 1 in a plane (horizontal plane in this example) perpendicular to the Z axis. In this case, the illumination area 63 on the reticle 3
Is a rectangular shape elongated in the X direction. At the time of exposure, the reticle 3 and the wafer 5 are scanned in synchronization with the Y direction (scanning direction) with the projection magnification β as a speed ratio by a stage system described later.
Thus, the pattern in the pattern area of the reticle 3 is sequentially transferred to each shot area on the wafer 5.

FIG. 2 is a partially cutaway side view of the projection exposure apparatus of FIG. 1 viewed in the -X direction (the position of the reticle stage is different), and FIG. 3 is a reticle stage of FIG. FIG. 4 is a block diagram showing a control system of the projection exposure apparatus.

In FIG. 1, a flat supporting member 13 is provided on a base member 10 via four vibration isolating tables 12, and a projection optical system 4 is provided at an opening at the center of the supporting member 13. . The anti-vibration table 12 is an active anti-vibration table including an air pad and an electromagnetic actuator for vibration control. For example, the support member 13 is provided with a plurality of acceleration sensors, and according to detection values of these acceleration sensors. By driving these electromagnetic actuators, the vibration transmitted from the floor via the base member 10 to the support member 13 and eventually to the exposure main body, and the vibration generated by driving the stage of the exposure main body and the like are rapidly attenuated. Is configured.

The projection optical system 4 is provided on the bottom of the support member 13.
, A flat wafer base 9 is suspended via, for example, four first columns 11 (or a pair of U-shaped columns or the like). In a state where there is no vibration, the upper surface of the wafer base 9 is parallel to a horizontal plane (XY plane), and the wafer frame 8 is mounted on the wafer base 9 via an air bearing so as to be movable in the X and Y directions.
X direction on the wafer frame 8 via an air bearing,
A wafer stage 7 is mounted movably in the Y direction, and a wafer 5 is suction-held on the wafer stage 7 via a wafer holder (not shown).

The wafer stage 7 is driven on the wafer frame 8 in the X and Y directions by, for example, a linear motor. In this projection exposure apparatus, the wafer stage 7
The weight of the wafer frame 8 is set to be 9 times or more the weight of the
When driven by W1, the driving reaction force moves the wafer frame 8 in the opposite direction at an acceleration of αW1 / 9 or less, so that the center of gravity of the stage system including the wafer stage 7 and the wafer frame 8 does not change. Therefore, there is an advantage that vibration during scanning exposure hardly occurs. Further, since the movement amount of the wafer frame 8 is small, the size of the wafer base 9 can be reduced, and the size of the projection exposure apparatus as a whole can be reduced.

The wafer stage 7 also incorporates a Z tilt mechanism for controlling the focus position (position in the Z direction) of the wafer 5 and the tilt angle. The wafer stage 5
Are perpendicular to the mirror surface 29X, which is substantially perpendicular to the X-axis, and are machined into a mirror surface 29Y which is substantially perpendicular to the Y-axis (see FIG. 2). A measurement beam composed of a laser beam is emitted from each of the interferometer main units 18X and 18Y. Reference mirrors 16X and 16Y are fixed to the lower side of the projection optical system 4 corresponding to the mirror surfaces 29X and 29Y, respectively.
A reference beam composed of the laser beam from 18Y is emitted via the light transmitting and receiving units 17X and 17Y. The X-axis interferometer main unit 18X detects the X coordinate of the wafer stage 7 with reference to the reference mirror 16X, and the Y-axis interferometer main unit 18Y detects the Y coordinate of the wafer stage 7 with reference to the reference mirror 16Y. Is detected.

The measurement beams from the interferometer main units 18X and 18Y are actually composed of three axes of measurement beams spaced apart in the horizontal direction and the Z direction. The coordinates or the Y coordinates are measured, and these measured values are supplied to the stage control system 82 in FIG. 4 and the main control system 91 that controls the overall operation of the apparatus. The stage control system 82 performs arithmetic processing on the measured values, thereby performing yawing (rotation angle about the Z axis) and pitching (rotation about the X axis) of the wafer stage 7 together with the X coordinate and the Y coordinate of the wafer stage 7. Rotation angle) and rolling (rotation angle around the Y axis).

Since the optical axes of these measurement beams almost pass through the optical axis AX, an Abbe error due to yawing of the wafer stage 7 is unlikely to occur, but the mirror surfaces 29X, 2
Since the position of 9Y and the surface of the wafer 5 are displaced in the Z direction, the measured values of the X coordinate and the Y coordinate are slightly mixed with Abbe error due to the rolling and pitching of the wafer stage 7. Therefore, the stage control system 82 corrects the X coordinate and the Y coordinate of the wafer stage 7 based on the measured rolling and pitching, and based on the corrected coordinates, the wafer via a wafer stage driving unit 83 such as a linear motor. The operation of the stage 7 is controlled.

As shown in FIG. 1 and FIG.
An optical and oblique incidence type auto focus sensor (not shown) and an off-axis type image processing type alignment sensor 67, for example, are provided on the bottom surface of the projection optical system 4 in proximity to the side surface of the projection optical system 4. The Z-tilt mechanism in the wafer stage 7 is driven by an auto-focus method and an auto-leveling method based on the focus positions of a plurality of points on the wafer 5 measured by the auto-focus sensor. The area is focused on the image plane of the projection optical system 4.

The alignment sensor 67 irradiates a wafer mark on the wafer 5 with illumination light, and supplies an image signal obtained by capturing an image of the mark to the alignment signal processing system 87 shown in FIG. Alignment signal processing system 87
Performs the position detection of the wafer mark based on the image signal, and calculates the array coordinates of each shot area on the wafer 5 from the position detection result by, for example, the enhanced global alignment (EGA) method. Further, a reference mark member 6 having a surface at the same height as the surface of the wafer 5 is fixed near the wafer 5 on the wafer stage 7, and is arranged on the reference mark member 6 at predetermined intervals in the X direction for reticle alignment. Pair of two-dimensional fiducial marks 65A, 6
5B, and two-dimensional reference marks 6 arranged at predetermined intervals in the Y direction from the centers of these reference marks 65A, 65B.
6 are formed.

The alignment sensor 67 measures the amount of displacement from the detection center of the reference mark 66 in a state where the reference marks 65A and 65B are aligned with the corresponding marks on the reticle stage as described later. A baseline amount, which is the distance between the detection center 67 and the center of the pattern image of the reticle 3 (exposure center), can be obtained, and the array coordinates of each shot area on the wafer 5 are corrected to the coordinates corrected by the baseline amount. By driving the wafer stage 7 based on this, alignment is performed with high accuracy.

Next, in FIG. 1, a flat reticle base 15 is installed on the upper surface of the support member 13 via, for example, four second columns 14 arranged so as to surround the projection optical system 4. . Reticle base 1 when there is no vibration
5 is also parallel to the horizontal plane, and the coarse movement stage 28 is slidably movable in the Y direction on the upper surface via an air bearing portion 28a and along a guide (not shown) arranged along the Y axis. Is mounted, and a reticle stage 35 as a fine movement stage is arranged in a coarse movement stage 28 in a nested structure (see FIG. 3), and the reticle 3 is placed on the reticle stage 35.
Is held by suction. The reticle stage 35 is also slidably mounted two-dimensionally on the reticle base 15 via the air bearing portion 35a.

The movers 27R, 2R fixed to both ends of the coarse movement stage 28 in the X direction and each including a permanent magnet are provided.
7L, slider 2 fixed on reticle base 15
Reticle frame 2 slidably arranged in the Y direction along 5R and 25L and including stators each comprising a coil
6R, 26L, and a pair of Y-axis linear motors 62R,
62L, and these linear motors 62R, 62R
L drives coarse movement stage 28 in the Y direction. As shown in FIG. 3, the reticle stage 35 is driven in a non-contact manner with respect to the coarse movement stage 28 in the X direction by an actuator 68 using, for example, Lorentz force.
In the direction, non-contact driving is performed by so-called EI core type actuators 33A to 33D using electromagnetic force (these are collectively referred to as “actuator 33”). At this time, the reticle stage 35 can be minutely rotated by controlling the drive amounts of the plurality of actuators 33A to 33D.

Also in this case, the weight of the reticle frames 26R and 26L is set to be 9 times or more the weight of the stage system including the reticle stage 35 and the coarse movement stage 28, and the coarse movement stage 28 (the reticle stage 35) is used.
Is moved in the Y direction at an acceleration αR1, and the reticle frames 26R, 2R are driven by the driving reaction force.
Since 6L moves in the reverse direction at an acceleration of αR1 / 9 or less, the position of the center of gravity of the stage system including coarse movement stage 28, reticle stage 35, and reticle frames 26R, 26L does not change. Therefore, vibration during scanning exposure hardly occurs, and the amount of movement of the reticle frames 26R, 26L is small.

As shown in FIG. 1, reticle stage 35
Moving mirror 30X elongated along the Y direction on the side surface in the -X direction
Is fixed, and the interferometer body 20 is fixed to the column 14.
The measurement beam emitted from X is transmitted and received by the light transmission / reception unit 19X.
Irradiates the movable mirror 30X along the X axis.
An X-axis reference mirror 21X and a Y-axis reference mirror 21Y are fixed to the upper side of the projection optical system 4, and the interferometer main body 20X
The reference beam emitted from the reticle is irradiated on the reference mirror 21X, and the interferometer main unit 20X detects the X coordinate of the reticle stage 35 with reference to the reference mirror 21X. Incidentally, instead of using the movable mirror 30X, the reticle stage 35
May be mirror-finished.

As shown in FIG. 2, the reticle stage 35
Corner mirror movable mirror 30Y on the side in the −Y direction
Is fixed, and the interferometer body 20 is fixed to the column 14.
The measurement beam emitted from the Y
The moving mirror 30 </ b> Y is irradiated along the Y-axis through the openings of the Y and coarse movement stages 28. Then, the reference beam from the interferometer main body 20Y is irradiated on the reference mirror 21Y,
The interferometer main unit 20Y detects the Y coordinate of the reticle stage 35 with reference to the reference mirror 21Y. Interferometer body 2
The measurement beams from 1X and 21Y are actually composed of measurement beams of three axes arranged apart in the horizontal direction and the Z direction, and the X coordinate or the Y coordinate is measured for each measurement beam of each of these axes. These measured values are also supplied to the stage control system 82 and the main control system 91 in FIG. The stage control system 82 calculates the yaw, pitch, and rolling of the reticle stage 35 along with the X and Y coordinates of the reticle stage 35 by arithmetically processing the measured values.

However, as can be seen from FIG. 3, the optical axes of these measurement beams almost pass through the optical axis AX, and as can be seen from FIGS. 1 and 2, the optical axes of these measurement beams are the reticle. 3 is arranged at substantially the same height as the pattern surface of the reticle stage 35,
Abbe errors due to pitching and rolling hardly occur. Therefore, the stage control system 82 controls the reticle stage driving unit 84 (the linear motor 62) based on the X coordinate, Y coordinate, and yaw of the wafer stage 7 to be measured.
R, 62L and actuators 33, 68) to control the operations of coarse movement stage 28 and reticle stage 35.

At the time of scanning exposure, the linear motors 62R, 62R
The coarse movement stage 28 is driven at a constant speed in the Y direction via the 2L, and the reticle stage 35 is two-dimensionally moved relative to the coarse movement stage 28 so as to reduce the synchronization error between the wafer stage 7 and the reticle stage 35. Driven. Further, the pitching and rolling of the reticle stage 35 determine the linear motors 62R and 62L and the actuator 3
3,68 operating states are monitored.

In FIG. 1, the reticle base 15
The illumination system 2 is fixed via a third column (not shown) installed so as to surround the reticle frames 26R and 26L, and the exposure light source system 1 is supported by another support mechanism (not shown). In this projection exposure apparatus, a wafer base 9, a wafer frame 8, a wafer stage 7, a first column 11, a support member 13, a projection optical system 4, a second column 14,
The reticle base 15, the coarse movement stage 28, the reticle stage 35, and the linear motors 62R and 62L constitute an exposure main body. By using the columns 11 and 14, the exposure main body has a hierarchical structure. Further, since the exposure main body is fixed to the support member 13 as a whole, when the exposure main body vibrates in the Z direction, the projection optical system 4, the pattern forming surface of the reticle 3, and the surface of the wafer 5 are simultaneously. It vibrates in the Z direction by the same amount, and the conjugate relationship between the reticle 3 and the wafer 5 does not break.

Next, the alignment system (reticle alignment system) on the reticle stage side will be described in detail. As shown in FIG. 1, a pair of reticle alignment systems 61 are arranged above reticle stage 35 so as to face each other in the X direction.
R and 61L are arranged.

The right reticle alignment system 61R
Optical path switching unit 24R, fixed unit 23R1, optical path division unit 23
R2, a detection unit 22R, and an illumination unit _IS61R .

Here, the reticle alignment system 61R on the right side will be described with reference to FIG.
Illumination light from the light source LS _R in _61R (e.g., light of the same wavelength as the exposure light) AR is a lens LN _R1, deflecting mirror MI
Through _R and lens LN _R2, it is guided to the light splitting member 23R _C of the optical path splitting unit 23R2. Light splitting member 23R illumination light AR reflected deflected by _C, the first objective lens system (objective optical system) in the fixed portion 23R1 23R _b and the deflection mirror 23
R _a , and a reticle mark 64A _R1 (or 64) as a test mark formed on the back surface of the reticle via the prism 24R _a (or 24R _b ) in the optical path switching unit 24R.
A _R2 ) is illuminated. After that, the reflected light from the reticle mark 64A _R1 (or 64A _R2 ) follows the reverse optical path again, and the optical path switching unit 24R and the fixed unit 23R1.
It passes through the light splitting member 23R _C in the optical path splitting unit 23R2 through, guided to the detection unit 22R. The light passes through the light splitting member 23R _C is deflecting mirror 22R _C and the second
Lens system (imaging optical system) the image pickup element (photoelectric detecting element) such as a CCD via a 22R _b is photoelectrically detected by 22R _a.

[0053] Here, the illumination optical system of the reticle alignment system 61R includes an illumination unit IS _61R, consists of a fixed portion 23R1 and the optical path switching section 24R, also the detection optical system of the reticle alignment system 61R is the optical path switching section 24R, It is composed of a fixed part 23R1 and a detection part 22R. For this reason, the fixed part 23R1 and the optical path switching part 24R in the reticle alignment system 61R are connected to the reticle alignment system 61R.
Part of the illumination optical system and part of the detection optical system are also used.

[0054] Incidentally, the light in the case of the illumination light from the light source LS _R in the illumination unit IS _61R and light of the same wavelength as exposure light, a part of the light from the exposure light source system 1 comprises an optical fiber bundle or the like guide may be used in place of the light source LS _R.

Here, as shown in FIG.
The R, fixing section 23R1 light from the reticle mark 64A ₁ formed on the outer edge side of the reticle 3 and the optical path splitting unit 2
First prism for guiding to detection section 22R via 3R2
And (optical path deflecting means) 24Ra, inward from the position of the reticle mark 64A ₁ In another reticle, i.e., the fixed portion 23R1 and the optical path of the light from the reticle mark 64A ₂ formed at a position different from the position of the reticle mark 64A ₁ A second prism (optical path deflecting means) 24Rb for guiding to the detection unit 22R via the division unit 23R2 is arranged in parallel in the Y direction.

In FIG. 6, reticle marks formed on different reticles are shown on the same reticle 3. In addition, not only the reticle marks formed on different reticles, but also the light from the reticle marks formed at different positions on the same reticle using the optical path switching unit 24R is used to reflect light from the epi-illumination mirror 23Ra and the first objective. It is also possible to guide to the lens system 23Rb.

The optical path switching section 24R includes a slide mechanism 86R.
(See FIG. 4) so as to be slidable in the Y direction. That is, when the optical path switching unit 24R slides in the Y direction by the slide mechanism 86R based on a control signal from the optical path switching control system 85 controlled by the main control system 91, the prism located in the optical path of the illumination light AR is moved. The first prism 24Ra and the second prism 24Rb are selectively exchangeable, and are selectively positioned in the optical path of the illumination light AR. First optical path thereby to guide the light from the reticle mark 64A ₁ to through the first prism 24Ra and epi-illumination mirror 23Ra first objective lens system 23Rb
(See FIG. 7 (a)) or the second optical path of light from the reticle mark 64A ₂ for guiding the through second prism 24Rb and epi-illumination mirror 23Ra first objective lens system 23RB (FIG 7 (b) see) is selectively formed, the reticle mark 64A ₁ or reticle mark 64A ₂ can be selectively observed.

First prism 24Ra and second prism 2
4Rb are prisms each having a parallelogram-shaped cross section. As shown in FIG. 8, the optical path length from the incident surface of the first prism 24Ra to the first reflection surface (total reflection surface) is D1, and the first prism is a first prism 24Ra. The optical path length from the first reflecting surface to the second reflecting surface (total reflecting surface) of 24Ra is D2, the optical path length from the second reflecting surface to the emitting surface of the first prism 24Ra is D3, and the material forming the first prism 24Ra. Is N, the optical path length from the entrance surface of the second prism 24Rb to the first reflection surface (total reflection surface) is D1 ', and the first reflection surface to the second reflection surface (total reflection surface) of the second prism 24Rb. ) Is D2 ′, and the optical path length from the second reflection surface to the emission surface of the second prism 24Rb is D2 ′.
3 ′, when the refractive index of the material forming the second prism 24Rb is N ′, (D1 / N) + (D2 / N) + (D3 / N) = (D1 ′)
/ N ') + (D2' / N ') + (D3' / N '). That is, the first prism 24Ra
The optical path length [(optical path length) / (refractive index of the prism)] in the inside and the optical path length in the second prism 24Rb are equal to each other.

On the other hand, the left reticle alignment system 61
L has exactly the same configuration as the right reticle alignment system 61R. For example, as shown in FIG.
4L, a fixing unit 23L1, an optical path division unit 23L2, a detection unit 22L, and an illumination unit IS _61L .

Here, the specific configuration of the left reticle alignment system 61L is the same as that of the right reticle alignment system 61R described with reference to FIG. 5, and a detailed description thereof will be omitted. The state when the left reticle alignment system 61L is viewed from the back corresponds to the configuration of reticle alignment system 61L in FIG.

[0061] Then, the illumination optical system of the reticle alignment system 61L includes an illumination unit IS _61L, consists of a fixed portion 23L1 and the optical path switching section 24L, The detecting optical system of the reticle alignment system 61L, the optical path switching section 24L, fixed It comprises a unit 23L1 and a detection unit 22L. For this reason,
Fixed part 23L1 in reticle alignment system 61L
And the optical path switching unit 24L includes a reticle alignment system 61.
Part of the illumination optical system L and part of the detection optical system are also used.

[0062] The illumination unit IS _61L includes a light source LS _L, lens LN _L1, has a deflection mirror MI _L and lens LN _L2, the optical path splitting unit 23L2 has a light splitting member 23L _C. The fixed portion 23L1 has a first objective lens system (objective optical system) 23L _b and deflection mirrors 23L _a, has a detection unit 22L is deflecting mirror 22L _C, the second lens system (imaging optical system ) 23L _b and an image pickup element such as a CCD (a photoelectric detecting element) has a 22L _a.

Here, as shown in FIG.
The L, a fixed portion 24L1 light from the reticle mark 64B ₁ formed on the outer edge side of the reticle 3 and the optical path splitting unit 23
First prism 2 for guiding to detection section 22L via L2
4La and other reticle (or the same reticle) for guiding the detector 22L light through the fixing portion 23L1 and the optical path splitting unit 23L2 from the reticle mark 64B ₂ formed on the inner side than the position of the reticle mark 64B ₁ in Second
The prisms 24Lb are juxtaposed in the Y direction. The first prism 24La provided in the optical path switching unit 24L
And the second prism 24Lb are provided with the first prism 24Ra and the second prism 24 provided in the optical path switching unit 24R.
Each has the same shape as Rb.

The optical path switching section 24L includes a slide mechanism 86L.
(See FIG. 4) so as to be slidable in the Y direction. That is, when the optical path switching unit 24L slides in the Y direction by the slide mechanism 86L based on a control signal from the optical path switching control system 85 controlled by the main control system 91, the first prism 24La is placed in the optical path of the illumination light AR. And the second
One of the prisms 24Lb is positioned. Thus the light from the reticle mark 64B ₁ first prism 24La,
First objective lens 23 via epi-illumination mirror 23La
First optical path or reticle mark 64B for guiding to Lb
_{A second} optical path for guiding the light from 2 to the first objective lens 23Lb via the second prism 24Lb and the mirror 23La for epi-illumination is formed.

As shown in FIG. 3, a pair of reticle marks 64A ₁ (or 64A ₂ ) and 64B ₁ (or 64B ₂ ) are formed on the pattern surface of reticle 3 so as to sandwich pattern area 69 in the X direction. Have been. Actually, a plurality of pairs of reticle marks are formed at predetermined intervals in the Y direction, and the reticle marks 64A ₁ (or 64A ₂ ) and 64B ₁ (or 64B ₂ ) have a line and space having a predetermined pitch in the X direction. Patterns (hereinafter referred to as “L / S patterns”),
This mark is a combination of an L / S pattern having a predetermined pitch in the Y direction. The reference marks 65A and 65B on the reference mark member 6 shown in FIG. 1 are projected images of the reticle 3 on the reticle marks 64A ₁ (or 64A ₂ ) and 64B.
It is formed of L / S patterns arranged in a frame shape having a size surrounding ₁ (or 64B ₂ ).

At the time of reticle alignment, control from the optical path switching control system 85 depends on the type of the reticle, that is, whether the reticle has the reticle marks 64A ₁ and 64B ₁ or the reticle where the reticle marks 64A ₂ and 64B ₂ have been formed. The optical path switching units 24R and 24L are slid in the Y direction by the slide mechanism 86L based on the signal, and the illumination light AR of each of the reticle alignment systems (61R and 61L).
The first prism (24Ra, 24La) or the second prism (24Rb, 24Lb) is selectively set in the optical path of. Thus the light from the reticle mark 64A ₁ first
The first objective lens system (2) is provided via a prism (24Ra, 24La) and an epi-illumination mirror (23Ra, 23La).
3Rb, light the second prism from the first optical path or the reticle mark 64A ₂ for guiding the 23Lb) (24Rb,
24Lb) and an epi-illumination mirror (23Ra, 23L)
a) through the first objective lens system (23Rb, 23Lb)
Can be selectively formed. In the following description, the case where the first optical path is formed will be described as an example.

Next, the reference mark 6 on the reference mark member 6
After positioning the wafer stage 7 so that the centers of 5A and 65B substantially coincide with the optical axis AX, the reference marks 65A and 65B are aligned.
Reticle mark 64A on image formed by projection optical system 4 of 65B
Reticle stage 35 so that ₁ , 64B ₁ almost matches.
Position. Then, the right side of the reticle alignment systems 61R, illumination light AR having the same wavelength as exposure light IL from the illumination unit IS _61R is reflected by the half mirror for example, the optical path splitting unit 23R2, the first objective of the internal fixed unit 23R1 Lens system 23Rb and mirror 23Ra for epi-illumination
Is bent downward through Thereafter, the light reflected and deflected by the epi-illumination mirror 23Ra is transmitted to the optical path switching unit 24R.
Mark 64A via the first prism 24Ra
₁ to epi-illumination a. At this time, the illumination light AR is the exposure light IL
Is the same wavelength as the illumination light AR passing through the periphery of the reticle mark 64A ₁ is irradiated on the reference mark 65A through the projection optical system 4, the illumination light AR reflected by the reference mark 65A is a projection optical through the system 4 forms an image of the reference mark 65A in the vicinity of the reticle mark 64A _1.

The illumination light reflected by the reference mark 65A and transmitted through the reticle 3, and the reticle mark 64A
_The illumination light directly reflected at ₁ is transmitted to the first light path switching unit 24R.
Prism 24Ra, fixed part 23R1, and optical path dividing part 2
It is guided to the detection unit 22R via 3R2. As a result, the image of the reticle mark 64A ₁ and the reference mark 65A is formed at the imaging surface of the imaging element 22Ra, each mark (64A
₁ , 65A) is transmitted to the image sensor 22Ra.
Are supplied to a mark detection system control system 85 shown in FIG.
The mark detection system control system 85 processes the image signal,
Reticle mark 64A _{1 with} respect to reference mark 65A image
Of the image in the X and Y directions is detected.

[0069] In the same manner, in imaging field of the imaging element L22 _a of the reticle alignment system 61L, the reticle mark image regarding the reticle mark 64B ₁ on the reference mark image and the reticle 3 with respect to a reference mark 65B on the reference mark member 6 Are formed, and each mark (64B ₁ , 65
FIG image signal from the image sensor 22L _a related image of B) 4
Are supplied to a mark detection system control system 85 shown in FIG. The mark detection system control system 85 processes the image signal to thereby control the reticle mark 64 for the image of the reference mark 65B.
X direction of the image of B _1, it is possible to detect the positional deviation amount in the Y direction. These displacement amounts are determined by the main control system 91 in FIG.
The main control system 91 controls the stage control system 82 so that, for example, the amount of displacement thereof is symmetrically minimized.
The position of the reticle stage 35 is adjusted via. As a result, the reticle 3 is positioned with high accuracy with respect to the coordinate system on the wafer stage 7 side, and the reticle alignment is completed.

After the reticle alignment is completed, a transfer pattern formed on the reticle 3 on the wafer 5 is exposed. In this case, the optical path switching units 24R and 24R are exposed.
When the first optical path is formed by 4L, the optical path switching unit 2
Exposure can be performed without retracting the 4R and 24L from above the reticle. Note that the light path switching unit 24
Of course, R and 24L may be retracted from the reticle.

According to the reticle alignment system provided in the projection exposure apparatus, it is possible to detect reticle marks formed at different positions on the reticle without moving the first objective lens of the detection optical system. . Further, even when a reticle mark at a different position is detected, the focus position of the detection optical system does not shift, so that it is not necessary to refocus. Further, even when the prism of the optical path switching unit is replaced, the spherical aberration of the detection optical system does not change, so that there is no need to adjust the optical characteristics such as correcting the aberration again.

Further, in this projection exposure apparatus, a reticle alignment device having optical path switching means for guiding light from reticle marks formed at different positions on the reticle to the detection optical system without changing the focus position of the detection optical system. Since the system is provided, the position of the reticle mark can be accurately detected even when the reticle is changed to a position where the reticle mark is formed.

In the above-described embodiment, an example is shown in which each of the optical path switching sections (24R, 24L) includes the first prism and the second prism. However, the optical path switching section includes the first prism to the n-th prism. The first prism
The optical path length from the entrance surface of the prism to the first reflection surface is D1
1. The optical path length from the first reflecting surface to the second reflecting surface of the first prism is D12, the optical path length from the second reflecting surface to the exit surface of the first prism is D13, and the refractive index of the material forming the first prism Is N1, the optical path length from the incident surface of the second prism to the first reflecting surface is D21, the optical path length from the first reflecting surface to the second reflecting surface of the second prism is D22, and the second is the second optical path of the second prism.
The optical path length from the reflecting surface to the emitting surface is D23, the refractive index of the material forming the second prism is N2, the optical path length from the incident surface of the n-th prism to the first reflecting surface is Dn1, and the first optical path of the n-th prism is The optical path length from the reflecting surface to the second reflecting surface is Dn2,
The optical path length from the second reflecting surface to the exit surface of the n-th prism is D
n3, where Nn is the refractive index of the material forming the n-th prism, (D11 / N1) + (D12 / N1) + (D13 / N1) = (D21 / N2) + (D22 / N2) + (D23) / N2) = (Dn1 / Nn) + (Dn2 / Nn) + (Dn3 / Nn). That is, the first prism
Optical optical path length in the n-th prism [(optical path length) /
(Refractive index of prism)] are equal to each other.

In this case, the positions of the reticle marks formed at a plurality of different positions can be detected.

Next, a description will be given of a projection exposure apparatus according to the second embodiment. The projection exposure apparatus according to the second embodiment is obtained by changing the optical path switching unit of the projection exposure apparatus according to the first embodiment to an optical path switching unit described with reference to FIG. Since the configuration of the pair of reticle alignment systems (61R, 61L) in the second embodiment is the same, one reticle alignment system 61R will be described as a representative.

[0076] FIG. 9 (a), the (b), the optical path switching section 24R is mirror reflected illumination light from the reticle mark 64A ₁ formed on the outer edge side of the reticle 3 23Ra and the first objective lens the first surface reflection mirror pair for guiding the 23Rb (light path deflecting means) 70R (see Fig. 9 (a)), the inner side than the position of the reticle mark 64A ₁ in another reticle, i.e., the position of the reticle mark 64A ₁ different positions in the formation reticle mark 64A ₂ second surface reflecting mirror pair for guiding the reflected illumination light mirror 23Ra and the first objective lens 23Rb light from (the optical path deflecting means) 71R
(See FIG. 9B) are arranged side by side in the Y direction. Although FIG. 9 shows a case where reticle marks formed at different positions on different reticles are detected, it is also possible to detect reticle marks formed at different positions on the same reticle. is there.

The optical path switching section 24R includes a slide mechanism 86R
(See FIG. 4) so as to be slidable in the Y direction. That is, when the optical path switching unit slides in the Y direction by the slide mechanism 86R based on a control signal from the optical path switching control system 85 controlled by the main control system 91, the first surface reflection mirror is placed in the optical path of the illumination light AR. Either the pair 70R or the second surface reflection mirror pair 71R is set. Thus the light from the reticle mark 64A ₁ first
Surface reflection mirror pair 70R and mirror 23Ra for epi-illumination
Through the first optical path (see Fig. 9 (a)) or second surface reflection mirror pair 71R and incident-light illumination mirror 23Ra light from the reticle mark 64A ₂ for guiding the first objective lens system 23Rb through A second optical path (see FIG. 9B) for guiding to the first objective lens system 23Rb can be selectively formed.

The first pair of surface reflection mirrors 70R is composed of two surface reflection mirrors 70Ra and 70Rb whose reflection surfaces are arranged in parallel, and the second surface reflection mirror pair 71R has a parallel reflection surface. 2 which is located in
Surface reflection mirrors 71Ra and 71R
b. The first surface reflection mirror pair 70R and the second surface reflection mirror pair 71R are in a virtual space formed by the surface reflection mirrors 70Ra and 70Rb of the first surface reflection mirror pair 70R (FIG. 10).
In (a), the surface reflection mirror 70Ra, the surface reflection mirror 70Rb and the space represented by the broken line), and the second
Optics in a virtual space formed by the surface reflection mirror 71Ra and the surface reflection mirror 71Rb of the surface reflection mirror pair 71R (in FIG. 10B, in the space represented by the surface reflection mirror 71Ra, the surface reflection mirror 71Rb, and the broken line). The optical path lengths are made equal.

On the other hand, reticle alignment system 61L
Since it is the same as the reticle alignment system 61R on the right side described with reference to FIG. 9 and FIG.
Reticle alignment system 6 from the back to left side of FIG.
The state when looking at 1L corresponds to the configuration of reticle alignment system 61L in FIGS.

[0080] As shown in FIG. 9, the optical path switching section 24L at the reticle alignment system 61L, the mirror reflected illumination light from the reticle mark 64B ₁ formed on the outer edge side of the reticle 3 23La and the first objective lens 23Lb second for directing the first and the surface reflecting mirror pairs 70L, mirror reflected illumination light from the reticle mark 64B ₂ formed on the inner side than the position of the reticle mark 64B ₁ 23La and the first objective lens 23Lb for guiding The surface reflection mirror pair 71L is arranged in the Y direction. The first surface reflection mirror pair 70 provided in the optical path switching unit 24L
L and the second surface reflection mirror pair 71L are connected to the optical path switching unit 24.
It has the same configuration as the first surface reflection mirror pair 70R and the second surface reflection mirror pair 71R provided on R.

The optical path switching section 24L includes a slide mechanism 86L.
(See FIG. 4) so as to be slidable in the Y direction. That is, when the optical path switching unit 24L slides in the Y direction by the slide mechanism 86L based on a control signal from the optical path switching control system 85 controlled by the main control system 91, the first surface reflection is caused in the optical path of the illumination light AR. Mirror pair 70L
Alternatively, one of the second pair of surface reflection mirrors 71L is set. Thus the light from the reticle mark 64B ₁ first surface reflection mirror pair 70L and epi-illumination mirror 23
The first objective lens system 23Lb through the first optical path or the second surface reflecting mirror pair 71L and epi-illumination mirror 23La the light from the reticle mark 64B ₂ for guiding the first objective lens system 23Lb through the La The second optical path for guiding can be selectively formed.

This projection exposure apparatus also has a reticle alignment system having optical path switching means for guiding light from reticle marks formed at different positions on the reticle to the detection optical system without changing the focus position of the detection optical system. Therefore, even when the reticle is changed to a position where the reticle mark is formed,
The position of the reticle mark can be accurately detected.

In the second embodiment described above,
For example, a virtual space formed by two surface reflection mirrors in the first surface reflection mirror pair (70R, 70L), and a virtual space formed by two surface reflection mirrors in the second surface reflection mirror pair (71R, 71L). The virtual space is
In FIG. 9, the thicknesses are made equal in the vertical direction (up and down direction) in the plane of the paper, and then the optical path lengths of both virtual spaces are compared. That is, in the above second embodiment,
Although the lengths of the end faces of each pair of surface reflection mirrors (70R and 71R or 70L and 71L) are made to match in the vertical direction (up and down direction) on the paper surface in FIG. 9, actually, each surface reflection mirror pair ( 70R, 70L, 71R, 71L) need only be large enough to allow the effective light flux to pass through the optical path between the falling illumination mirrors (23Ra, 23La) and the reticle 3 without any excess or deficiency. Each of the surface reflection mirrors in each of the surface reflection mirror pairs (70R, 70L, 71R, 71L) can have a size as shown by oblique lines in FIG.

In the above-described second embodiment, the optical path switching units 24R and 24L are provided with two surface reflection mirrors. However, three or more surface reflection mirrors may be provided. Also in this case, it is necessary to equalize the optical path length in the virtual space formed by three or more surface reflection mirrors.

In the second embodiment, the first pair of surface reflection mirrors (70R, 70L) or the second
The reticle marks formed at the two positions are detected by switching and using the pair of surface reflection mirrors (71R, 71L), but the optical path lengths in the virtual space formed by the pair of surface reflection mirrors are equal. By continuously changing the inclination and the distance of the surface reflection mirror pair while maintaining the state, the detection position can be changed continuously.

In each of the above embodiments, the optical path switching means is used in the reticle alignment system.
Although the position of the reticle mark formed at a different position is detected, the present invention is not limited to this.
(A system), it is also possible to detect the position of a wafer mark formed at a different position by using the optical path switching means.

Referring to the flow chart of FIG. 12, the manufacture of a semiconductor device as a micro device for forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the projection exposure apparatus shown in FIGS. The method will be described.

First, in step S301 in FIG. 12, a metal film is deposited on one lot of wafers. In the next step S302, a photoresist is applied on the metal film on the wafer of the lot. Thereafter, in step S303, using the projection exposure apparatus shown in FIGS. 1 to 4, the image of the pattern on the mask is transferred to each shot area on the wafer of the lot through the projection optical system (projection optical module). Are sequentially exposed and transferred. Thereafter, in step S304, the photoresist on the one lot of wafers is developed, and in step S305, etching is performed on the one lot of wafers using the resist pattern as a mask, thereby forming a pattern on the mask. A corresponding circuit pattern is formed in each shot area on each wafer. Thereafter, a device such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer and the like. According to the above-described semiconductor device manufacturing method, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput.

In the projection exposure apparatus shown in FIGS. 1 to 4, a predetermined pattern (circuit pattern, electrode pattern, etc.) is formed on a plate (glass substrate).
A liquid crystal display element as a micro device can also be obtained. Hereinafter, a method of manufacturing a liquid crystal display device will be described with reference to the flowchart of FIG. 13, in a pattern forming step S401, a so-called photolithography step of transferring and exposing a mask pattern to a photosensitive substrate (a glass substrate coated with a resist) using the projection exposure apparatus shown in FIGS. Be executed. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. After that, the exposed substrate is
A predetermined pattern is formed on the substrate by going through the respective steps such as a developing step, an etching step, and a reticle peeling step, and the process proceeds to the next color filter forming step S402.

Next, in the color filter forming step S402, three colors corresponding to R (Red), G (Green), and B (Blue)
Many sets of dots are arranged in a matrix,
Alternatively, a color filter in which a set of three stripe filters of R, G, and B are arranged in a plurality of horizontal scanning line directions is formed. Then, after the color filter forming step S402,
The cell assembling step S403 is performed. In the cell assembling step S403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern forming step S401, the color filter obtained in the color filter forming step S402, and the like. In the cell assembling step S403, for example, a liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern forming step S401 and the color filter obtained in the color filter forming step S402, and a liquid crystal panel (liquid crystal cell) is formed. ) To manufacture.

Thereafter, a module assembling step S404
Then, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display device, a liquid crystal display device having an extremely fine circuit pattern can be obtained with high throughput.

[0092]

According to the observation apparatus of the present invention, the first optical path and the second optical path for guiding the light from the first position to the detection optical system while the focus position of the detection optical system remains unchanged by the optical path switching means. Since it is possible to switch between the second optical path for guiding light from the position to the detection optical system, it is possible to easily and highly accurately observe a plurality of objects to be observed by the detection optical system.

Further, according to the position detecting device of the present invention,
The light from the mark at the first position and the light from the mark at the second position are guided to the detection optical system while the focus position of the detection optical system is kept unchanged by the light path switching means. Since the switching between the second optical path and the second optical path can be performed, the positions of the plurality of marks can be easily and accurately detected by the detection optical system.

Further, according to the exposure apparatus of the present invention, since one of the reticle and the photosensitive substrate can be accurately detected as an object to be observed by the position detecting device, the reticle and the photosensitive substrate can be accurately detected. Can be performed very accurately.

Further, according to the method of manufacturing a micro device of the present invention, an image of a transfer pattern formed on a reticle can be faithfully formed on a photosensitive substrate. Can be.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing a projection exposure apparatus according to a first embodiment.

FIG. 2 is a projection exposure apparatus according to the first embodiment (FIG. 1).
FIG. 3 is a side view in which a part is cut away when viewed in the −X direction.

FIG. 3 is a plan view of a main part showing a reticle stage and the like of the projection exposure apparatus (FIG. 2) according to the first embodiment;

FIG. 4 is a block diagram showing a control system of the projection exposure apparatus according to the first embodiment.

FIG. 5 is a diagram for explaining a configuration of a reticle alignment system according to the first embodiment.

FIG. 6 is a diagram for explaining a configuration of an optical path switching unit according to the first embodiment.

FIG. 7 is a diagram for explaining an optical path switching state according to the first embodiment.

FIG. 8 is a diagram for explaining a configuration of an optical path switching unit according to the first embodiment.

FIG. 9 is a diagram for explaining a configuration of an optical path switching unit according to a second embodiment.

FIG. 10 is a diagram for explaining a virtual space formed by a pair of surface reflection mirrors of an optical path switching unit according to the second embodiment.

FIG. 11 is a diagram illustrating a modification of the pair of surface reflection mirrors of the optical path switching unit according to the second embodiment.

FIG. 12 is a flowchart illustrating a method for manufacturing a micro device according to an embodiment of the present invention.

FIG. 13 is a flowchart illustrating a method for manufacturing a micro device according to an embodiment of the present invention.

FIG. 14 is a diagram for explaining a conventional alignment mark observation method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Exposure light source system, 2 ... Illumination system, 3 ... Reticle, 4 ... Projection optical system, 5 ... Wafer, 35 ... Reticle stage, 24
R, 24L: optical path switching unit, 24Ra, 24Rb: prism, 61R, 61L: reticle alignment system, 64
a, 64b: reticle mark, 70R, 70L: surface reflection mirror pair.

Claims (10)

[Claims] 1. A detection optical system for condensing light from an object to be observed, a photoelectric detection element for photoelectrically detecting light passing through the detection optical system, and a first element on an observation surface where the object to be observed is installed In order to selectively observe the position of the first position and the second position different from the first position, light from the first position is transmitted to the detection optical system while keeping the focus position of the detection optical system unchanged. An observation apparatus comprising: an optical path switching unit that switches between a first optical path for guiding light and a second optical path for guiding light from the second position to the detection optical system. 2. An optical path switching unit comprising: a first optical path deflecting unit for forming the first optical path; and a second optical path deflecting unit for forming the second optical path interchangeably provided with the first optical path deflecting unit. Means, wherein the optical path length of the first light path in the first path deflecting means is equal to the optical path length of the second light path in the second path deflecting means. Claim 1.
Observation device as described. 3. The apparatus according to claim 2, wherein said first optical path deflecting means includes a first prism forming said first optical path, and said second optical path deflecting means includes a second prism forming said second optical path. The observation device according to claim 2, wherein 4. The first optical path deflecting means includes at least two surface reflecting mirrors forming the first optical path, and the second optical path deflecting means includes at least two surface reflecting mirrors forming the second optical path. The observation device according to claim 2, further comprising: 5. A detection optical system for condensing light from a mark formed on the object to be observed in order to detect a position of the object to be observed, and a photoelectric device for photoelectrically detecting light passing through the detection optical system. A detection element, and the detection optical system for selectively observing a mark at a first position and a mark at a second position different from the first position on an observation surface on which the object to be observed is installed. A first optical path that guides light from the mark at the first position to the detection optical system and a second optical path that guides light from the mark at the second position to the detection optical system while keeping the focus position unchanged. And a light path switching means for switching between the two. 6. The optical path switching means includes a first optical path deflecting means for forming the first optical path and a second optical path deflecting for forming the second optical path interchangeably provided with the first optical path deflecting means. Means, wherein the optical path length of the first light path in the first path deflecting means and the optical path length of the second light path in the second path deflecting means are equal to each other. Claim 5
The position detecting device as described in the above. 7. The light path deflecting means includes a first prism forming the first light path, and the second light path deflecting means includes a second prism forming the second light path. The position detecting device according to claim 6. 8. The first optical path deflecting means includes at least two surface reflecting mirrors forming the first optical path, and the second optical path deflecting means includes at least two surface reflecting mirrors forming the second optical path. The position detecting device according to claim 6, further comprising: 9. A projection optical system for projecting an image of a transfer pattern formed on a reticle onto a photosensitive substrate, and the reticle and the photosensitive substrate are used to perform relative positioning between the reticle and the photosensitive substrate. An exposure apparatus comprising: the position detection device according to any one of claims 5 to 8, which detects a position of any one of the conductive substrates as the object to be observed. 10. An exposure step of exposing a transfer pattern of a reticle onto a photosensitive substrate using the exposure apparatus according to claim 9, and a developing step of developing the photosensitive substrate exposed in the exposure step. A method for manufacturing a micro device, comprising: