JPH11135414A - Projection aligner and method for manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve throughput, to improve measurement precision, and to reduce running cost of a device. SOLUTION: Related to a TTR microscope wherein a first alignment mark on an original plate 13 and a first reference mark provided on a device are observed at the same time, while a second alignment mark on a substrate where the pattern of the original plate is exposed, and a second reference mark on the substrate or a substrate stage, are observed at the same time, with the substrate or the second reference mark observed through a projection optical system, first optical systems 401-407 wherein the first alignment mark and the first reference mark are observed at the same time, and second optical systems 20a-20f and 71-74, different system wherein the second alignment mark and the substrate or the second reference mark are observed at the same time, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image of an original plate such as a mask (reticle) having a predetermined pattern formed by a projection lens on a photosensitive substrate (a wafer surface coated with a resist).
The present invention relates to a projection exposure apparatus for printing by projection onto a device and a device manufacturing method, and more particularly to an improvement in an alignment technique for aligning an original plate and a substrate in such an apparatus and method.

[0002]

2. Description of the Related Art The progress of semiconductor technology has been increasing at an increasing rate in recent years, and accordingly, the progress of fine processing technology has been remarkable. In particular, the optical processing technology at the center is 1MDRA
We stepped into the submicron region with M as the boundary. A method that has been used so far as a means for improving the resolution is to fix the wavelength and increase the NA of the optical system. However, recently, the exposure wavelength has been changed from g-line to i-line,
An exposure apparatus using an excimer laser of 48 nm or 193 nm as an exposure light source has been proposed. These devices are
After the reticle alignment mark and the wafer alignment mark are photoelectrically detected and aligned, the pattern on the reticle is exposed on the wafer.

As an alignment method at this time, when exposure light is used for observing an alignment mark on a wafer, a large step is formed at the alignment position of the wafer, which adversely affects the actual element pattern. For this reason, a method of performing alignment using light having a wavelength different from the exposure light as a light source has been proposed. In the method of performing alignment using light having a wavelength different from the exposure light as a light source, since the exposure wavelength and the alignment wavelength are different, chromatic aberration exists in the projection lens, and the wafer and the reticle cannot be observed simultaneously. For this reason, TTL off-axis is generally adopted. TT
The alignment method in the form of L off-axis is
Since the reticle and the wafer are observed with different microscopes, an indirect error factor occurs in the relative alignment between the reticle and the wafer. Among the indirect error factors, the fluctuation of the baseline (the distance between the center of the shot at the alignment position and the center of the shot at the exposure position) greatly affects the alignment accuracy.
Therefore, using a TTL off-axis microscope and a TTR microscope, (1) the positional relationship between the exposure apparatus body and the reticle,
Measure the three positional relationships of (2) the positional relationship between the reticle and the fiducial mark, and (3) the positional relationship between the fiducial mark and the TTL off-axis microscope, and easily manage the baseline fluctuation. It has been proposed to be able to do this.

[0004]

In the alignment method in which the TTL off-axis is used, it is necessary to manage the fluctuation of the baseline. In order to measure the baseline fluctuation, (1) the positional relationship between the exposure apparatus body and the reticle, (2) the positional relationship between the reticle and the fiducial mark, and (3) the positional relationship between the fiducial mark and the TTL off-axis microscope. The three positional relationships are measured.

In the positional relationship (1), a mark serving as a reference for aligning a reticle fixed to the exposure apparatus body and a relative position between the reticle and the mark are detected by a TTR microscope. In the positional relationship (2), the relative position between the fiducial mark fixed to the wafer stage and the reticle is detected by a TTR microscope. In the positional relationship (3), the relative position between the fiducial mark and the reference mark in the TTL off-axis microscope is detected by the TTL off-axis microscope. At this time, the detection of the positional relationship of (1) and (2) is performed by a TTR microscope. The marks for detecting the positional relationship of (1) and (2) provided on the reticle are as follows:
Since they cannot be arranged at the same coordinates, they are arranged at different coordinate positions. For this reason, it is necessary to detect the positional relationship of (2) after detecting the positional relationship of (1), which is a cause of a decrease in throughput.

In addition, since the TTR microscope moves to the position for detecting the positional relationship of (2) after detecting the positional relationship of (1), the driving accuracy of the TTR microscope and the structure accompanying the movement of the TTR microscope. Deformation of an object or the like is a factor that deteriorates measurement accuracy.

Further, when an excimer laser is used as the exposure light, an excimer laser is required for detecting the positional relationship of (1) and (2). For this reason, the gas life of the excimer laser light source (the life required for the original exposure, but shorter) is shortened, which causes a rise in the running cost of the apparatus.

SUMMARY OF THE INVENTION An object of the present invention is to provide a projection exposure apparatus and a device manufacturing method using the same, which solve the problems of the prior art, improve throughput, improve measurement accuracy, and reduce the running cost of the apparatus. The goal is to mitigate this.

[0009]

In order to solve the above-mentioned problems, the present invention provides a projection exposure apparatus employing a TTL off-axis alignment method, in which an original plate is aligned. In addition, a TTR microscope for detecting a relative position between a reference mark provided on a substrate stage holding a photosensitive substrate and an original plate is provided as two separate optical systems.

That is, in the present invention, an original plate stage; a pattern to be exposed and held on the original plate stage, and first and second alignment marks (13a, 13b).
A first plate for aligning a master having
A reference mark (30e), a substrate stage, a projection optical system for projecting the pattern of the original plate onto a photosensitive substrate held on the substrate stage, and a second reference provided on the substrate stage. A TTL off-axis microscope (25) for observing the substrate or the second fiducial mark via the projection optical system; and the TT
A third reference mark (25h) provided in or on the optical path of the L off-axis microscope; the substrate or the second reference mark and the third reference mark based on the observation result by the TTL off-axis microscope First mark position detecting means (25g) for detecting a relative position with respect to the mark
And simultaneously observing the first alignment mark (13a) and the first fiducial mark, and simultaneously viewing the second alignment mark (13b) and the substrate or the second fiducial mark, and For the substrate or the second reference mark, via the projection optical system,
A TTR microscope (20) for observing; a relative position between the first alignment mark and the first reference mark, and a second alignment mark and the substrate or the second reference based on the observation result; A second mark position detecting means (20g) for detecting a relative position with respect to a mark, wherein the original plate stage and the substrate stage are driven based on a result of detection by the first and second position detecting means, and A projection exposure apparatus for aligning a substrate and a substrate and exposing the pattern of the original plate onto the substrate; wherein the TTR microscope is configured to observe the first alignment mark and the first reference mark at the same time. Optical system (401-407)
And a second optical system (20a to 20f, 71 to 74) of another system for simultaneously observing the second alignment mark and the substrate or the second reference mark. Features. Here, reference numerals in parentheses indicate reference numerals of corresponding elements in the embodiment.

In the device manufacturing method of the present invention, the original plate stage and the substrate stage are driven based on the detection results of the first and second position detecting means by using such an exposure apparatus. And aligning the substrate with the substrate, and exposing the pattern of the original plate onto the substrate.

Here, the first alignment mark and the first reference mark are observed and the second reference optical mark are observed by a separate system of the first and second optical systems, that is, the TTR microscope constituted by two microscopes. The observation of the alignment mark and the substrate or the second reference mark are all performed at the same time, thereby improving the throughput and the measurement accuracy.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of the present invention, illumination light used in the first optical system and the second optical system is light having different wavelengths. In this case, the illumination light used in the second optical system is usually exposure light, and the illumination light used in the first optical system is non-exposure light.

The first optical system and the second optical system can be driven integrally, and the positional relationship between the observation positions of each optical system is determined by the positional relationship between the first and second alignment marks. This is the same positional relationship as that described above, or the positional relationship in which the first and second alignment marks can be observed simultaneously. In other words, the first and second optical systems are used for positioning the original plate, and for the second reference mark (fiducial mark),
The arrangement does not need to be moved when detecting the relative position of the original plate.

Further, there is provided illuminating means for emitting illumination light used in the first optical system from below the first fiducial mark, wherein the first fiducial mark is located below the original plate, The system is for simultaneously observing the first alignment mark and the first reference mark illuminated by the illumination means from above the original plate.

At the time of exposure, the first alignment mark and the first reference mark are simultaneously observed by a TTR microscope, and the relative position between the first alignment mark and the first reference mark is determined based on the observation result. The position is detected by the second mark detecting means, and based on the detection result, the original plate stage is moved to position the original plate with respect to the first reference mark, and then the second alignment mark is moved by the TTR microscope. And the second reference mark are simultaneously observed, and based on the observation result, the relative position between the second alignment mark and the second reference mark is detected by the second mark detection means, and based on the detection result, The substrate stage is moved to align the substrate stage, and then the second reference mark and the third reference mark are observed with a TTL off-axis microscope. The second mark position detecting means Zui detecting the relative position of the second reference mark and third reference mark. That is, the baseline is measured. Exposure is performed in consideration of this detection result. Hereinafter, more specific embodiments of the present invention will be described through examples.

[0017]

FIG. 1 is a block diagram of a projection exposure apparatus according to one embodiment of the present invention. First, a configuration for performing exposure will be described. In FIG. 1, reference numeral 1 denotes an excimer laser used as an illumination light source. The excimer laser 1 is controlled by the control device 50. The pulse wave from the excimer laser 1 is
The light is expanded to an appropriate size by the diverging lens 2 and guided to the fly-eye lens 10 by the illumination optical system lenses 3, 5, 8 and the mirrors 4, 9. This pulse wave becomes uniform illumination light by the fly-eye lens 10 and illuminates the reticle 13 via the mirror 11 and the condenser lens 12.
The pattern of the reticle 13 to be illuminated
Is projected onto the wafer 19. The control device 50 monitors the position of the stage 15 with the interferometer 16, sends a control signal to the driving device 17, and drives the stage 15. The stage 15 is driven so as to repeat step and repeat. The excimer laser 1 is controlled to emit light in synchronization with the driving of the stage 15. Thereby, the pattern of the reticle 13 is printed on the wafer 19.

Next, a configuration for performing alignment will be described. A TTR microscope 20 is provided above the reticle 13. Illumination light for the TTR microscope 20 is extracted by the mirror 6. That is, the mirror 6 is driven by the driving device 7, and the driving device 7 is controlled by the control device 50. When the mirror 6 is driven into the optical path of the illumination optical system, the optical path of the illumination optical system is switched. The illumination light passes through the mirror 6 and is condensed by the condenser lenses 21 and 22 into the fiber 23.
And is introduced into the TTR microscope 20 via the fiber 23.

A TTL off-axis microscope 25 is provided below the reticle 13. TTL off-axis microscope 25
Is guided from the light source 26 through the fiber 27. The light source 26 is controlled by the control device 50.

FIG. 2 is an enlarged view of a part of FIG. The configuration of the TTR microscope 20 and the TTL off-axis microscope 25 will be described with reference to FIG. The description of the same elements as those in FIG. 1 will be omitted. First, the alignment mark 1 on the wafer is projected by the TTR microscope 20 through the projection lens 14.
9a, the configuration for observing the alignment reference mark 18 provided on the stage 15 will be described.

The illumination light emitted from the fiber 23 to the TTR microscope 20 is transmitted through a lens 20a and a half mirror 20.
b, illuminate the reticle 13 via the objective lens 20c and the mirror 20d. Further, the alignment mark 19 a on the wafer or the alignment reference mark 18 provided on the stage 15 is illuminated via the projection lens 14. The return light from each mark again passes through the projection lens 14, the mirror 20d, and the objective lens 20c, and then returns to the half mirror 20.
The light is reflected by b and forms an image on the imaging surface of the camera 20f by the lens 20e. The image signal of the camera 20f is processed by the processing device 20g.
, And the amount of displacement of each mark is calculated. The result is sent to the control device 50 and the driving device 1
7 and corrects the amount of displacement. Objective lens 20c, half mirror 20b, lens 20a, mirror 20d, lens 20e, camera 20f, processing device 2
0 g is driven by the driving device 24 as the TTR microscope 20. For details of the TTR microscope 20,
It will be described later.

Next, a configuration in which the TTR microscope 20 observes a positioning mark on the reticle 13 and a reference mark for positioning the reticle will be described.
As shown in FIG. 2, a reticle illuminating unit 30 is arranged below the reticle 13, and illuminates a positioning mark provided on the reticle 13 and a reticle positioning reference mark from below the reticle 13. FIG. 3 is an enlarged view of a part of FIG. 2 and shows details of the reticle illumination unit 30. Note that illustration and description of some of the same elements as those in FIGS. 1 and 2 are omitted.

As shown in FIG. 3, the illuminating light is guided by a fiber 30b from a light source 30a, and passes through a lens 30c and a mirror 30d.
And illuminate the alignment mark 13a on the reticle. The light source 30a is controlled by the control device 50. Reticle alignment reference mark 3 illuminated by illumination light
2e, the image of the alignment mark 13a on the reticle is reflected by the half mirror 20b via the mirror 20d of the TTR microscope 20 and the objective lens 20c as described above with reference to FIG. An image is formed on the imaging surface. The image signal of the camera 20f is processed by the processing device 20g, and the positional deviation amount between the alignment mark 13a on the reticle and the reticle alignment reference mark 30e (the deviation amount of the reticle 13 with respect to the reticle alignment reference mark 30e) is calculated. Is calculated. On the basis of this deviation amount, the control device 50 moves the reticle 13 by a reticle holding stage (not shown) and its driving device 41 and an interferometer 40 not shown in FIGS. It is aligned with the reference mark 30e.

Next, a configuration in which the TTL off-axis microscope 25 observes the alignment mark 19a on the wafer and the alignment reference mark 18 provided on the stage 15 via the projection lens 14 will be described. As shown in FIG. 2, the illumination light emitted from the fiber 27 to the TTL off-axis microscope 25 is applied to the projection lens 14 via a lens 25a, a half mirror 25b, an objective lens 25c, and a mirror 25d. Further, the positioning mark 19a on the wafer, the stage 15
Is illuminated.
The return light from each mark is again projected on the projection lens 14,
The light is reflected by the half mirror 25b via the mirror 25d and the objective lens 25c, and is imaged by the lens 25e. A TTL off-axis microscope reference mark 25h is arranged on the image plane. The image of the alignment mark 19a on the wafer or the alignment reference mark 18 provided on the stage 15 and the image of the reference mark 25h are formed on the imaging surface of the camera 25f by the lens 25i. The image signal of the camera 25f is processed by the processing device 25g, and the positional shift amount of each mark is calculated. The result is sent to the control device 50 and fed back to the drive device 17 to correct the position shift amount.

The reference mark 25h is formed in the TTL off-axis microscope 25. Instead, a reference mark is provided at another place and an independent light source for illuminating the reference mark is formed. The image of T
The reference mark image and the image from the wafer may be independently observed by combining with the image forming plane of the TL off-axis microscope 25.

Next, the operation at the time of baseline measurement will be described. First, a conventional measurement operation will be described with reference to FIG. In the figure, reference numeral 20d denotes a mirror 20d in the TTR microscope 20, and 25d denotes the TTL
5 shows a mirror 25d in the off-axis microscope 25.

First, with respect to the reticle 13, the relative position between the alignment mark 13a drawn on the reticle 13 and the reticle alignment reference mark 30e arranged on the exposure apparatus side is detected by the TTR microscope 20. Based on this detection result, the control device 50 causes the interferometer 40 and the driving device 41 to position the reticle 13 with respect to the reticle positioning reference mark 30e. Next, the reference mark 18 on the wafer stage is aligned with the aligned reticle 13. For this reason, the TTR microscope 20
Is moved by the driving device 24 to a position where the mirror 20d is at the position of 20dd. A mark 13b is drawn at a position on the reticle 13 corresponding to the position of 20dd. The position of the mark 13b relative to the mark 18b in the reference mark 18 on the wafer stage is measured by the TTR microscope 20 via the projection lens 14. Based on the measurement result, the control device 50 controls the interferometer 16 and the driving device 17
Moves the wafer stage 15 to align the reference mark 18 on the wafer stage with the mark 13b on the reticle.

Since the reference mark 18 on the wafer stage has been aligned with respect to the reticle 13, the reference mark in the TTL off-axis microscope 25 is compared with the mark 18c in the reference mark on the wafer stage by the TTL off-axis microscope 25. The relative position of 25h is measured. Thereby, the baseline can be measured.

The necessity of moving the TTR microscope 20 to the position of 20dd will be described. FIG. 6 is a plan view of the reticle 13. Reference numeral 601 denotes a range that can be irradiated with illumination light for exposure (a range that can be transmitted through the projection lens 14). 6
Reference numeral 02 denotes an area of a pattern to be exposed (transferred) drawn on the reticle 13. The positions of the marks 13a and 13b must be on the reticle 13 inside the range 601 and outside the area 602. Further, as described above, below the mark 13a, the reference mark 30e and its illumination unit 30 are arranged. For this reason, in order to observe the wafer side (through TTL) through the projection lens 14, it is necessary to use a TTL microscope 20 other than the position of the mark 13 a.
Must be at a position where the illumination light does not interfere with the illumination unit 30. Therefore, the mark 1 is located at a position as shown in FIG.
3b is arranged. Therefore, in order to align the reference mark 18 on the wafer stage with respect to the reticle 13, the TTR microscope moves the mark 1 from the position of the mark 13a.
It has to move to the position 3b, i.e. the position 20dd. Since the marks 13a and 13b are arranged on the left and right, the reference numerals of the left ones are 13a 'and 13a', respectively.
13b '.

Conventionally, the moving time of this TTR microscope is
This was a cause of a decrease in throughput. Further, the driving accuracy of the TTR microscope and the deformation of a structure or the like due to the movement of the TTR microscope are factors that deteriorate the measurement accuracy.

FIG. 7 is a view showing a conventional TTR microscope. The same elements as those shown in FIGS. 1 to 6 are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 7, in the conventional example, light incident on a TTR microscope passes through a mirror 20d and an objective lens 20c, further passes through a mirror 71, a relay lens 72, mirrors 73 and 74, and a half mirror 2
0b, lens 20e, camera 20f via mirror 75
Is formed on the imaging surface of. The same optical system is configured symmetrically. The description of the optical system on the opposite side is omitted.

Further, in this conventional configuration, since the left and right TTR microscopes are each one system, the illumination light is different between when observing the reticle when aligning the reticle and when observing the wafer with TTL. Must have the same wavelength as the exposure light. For this reason, when an excimer laser is used as the illumination light, when the reticle is observed, the TTL
Since the excimer laser is used when observing the wafer, the gas life of the excimer laser light source (the gas life required for the original exposure) is shortened, which increases the running cost of the apparatus. I was FIG. 4 shows the configuration of the TTR microscope used in this embodiment. Elements corresponding to those in FIG. 7 are indicated by the same numbers. The most different point from the conventional one in FIG. 7 is that the left and right TTR microscopes in FIG. 7 are each configured by one optical system, whereas in the present embodiment, each is configured by two optical systems. It is in the point.

In FIG. 4, camera 2 is moved from mirror 20d.
The system reaching 0f is an optical system for observing the wafer (reticle mark 13b and wafer-side mark 18b) by TTL. The system from the mirror 401 to the camera 407 is a reticle (reticle mark 13a and reference mark 30e).
Is an optical system for observing. In this embodiment, an optical system for observing the reticle after the mirror 401 is added. In this added optical system, as shown in FIG. 3, illumination light illuminated from below the reticle 13 enters the mirror 401, and the objective lens 402 and the mirror 40
3. An image is formed on the imaging surface of the camera 407 via the relay lens 404, the mirror 405, and the elector lens 406.

As described above, in this embodiment, independent optical systems for reticle observation and TTL observation are configured in the TTR microscope. For this reason, T
The problem caused by the driving of the TR microscope is that the two optical systems can be moved by the same driving system, and the arrangement of the two optical systems is changed according to the arrangement of the marks 13a and 13b in FIG. Can solve the problem. That is, an optical system after the mirror 401, which is an optical system for observing the reticle 13, is disposed above the mark 13a for aligning the reticle 13. Mark 13
Above b, an optical system after the mirror 20d, which is an optical system for observing the wafer on the TTL, is arranged. The arrangement of these optical systems may be an arrangement having the same positional relationship as the marks 13a and 13b, or an arrangement capable of simultaneously observing these marks even if the TTR microscope 20 does not move.

With this configuration, after measuring the reticle position,
The TTR microscope 20 does not move,
A TL off-axis microscope observation can be performed. For this reason,
Conventionally, the time required for moving the TTR microscope 20 can be reduced. Further, it is possible to eliminate a factor that deteriorates the measurement accuracy due to the movement of the TTR microscope 20. In order to solve the problem caused by the fact that the wavelength used during reticle observation is the same as the exposure light, the TTR microscope 20 is composed of two optical systems, so that the reticle observation optical system uses the exposure light. Light of a different wavelength can be used. This allows
Since an excimer laser is not used during reticle observation during reticle alignment, an increase in running cost can be prevented.

<Embodiment of Device Manufacturing Method> Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described. FIG. 8 shows a micro device (a semiconductor chip such as an IC or an LSI, a liquid crystal panel, a CCD, a thin film magnetic head,
2 shows a flow of manufacturing a micromachine or the like. Step 1
In (Circuit Design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. Step 3 (wafer manufacturing)
Then, a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process,
An actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 9 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. In step 12 (CVD), a green film is formed on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 15
In (resist processing), a resist is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus or exposure method to align and print the circuit pattern of the mask on a plurality of shot areas of the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the method of this embodiment, it is possible to manufacture a large-sized device, which was conventionally difficult to manufacture, at low cost.

[0039]

As described above, according to the present invention, T
A TR microscope is used to simultaneously observe a first alignment mark and a first reference mark simultaneously with a first optical system and a second alignment mark and a substrate or a second reference mark of another system. The second optical system to be observed has the following effects.

(1) The TTR microscope can be kept fixed during baseline measurement. Therefore, T
Compared to the conventional one that required TR microscope movement,
Throughput can be improved. (2) Since the TTR microscope can be kept fixed at the time of baseline measurement, measurement accuracy can be improved. (3) When observing the first alignment mark and the first reference mark, light having a wavelength different from that of the exposure light can be used.
Therefore, even when a light source such as an excimer laser is used as the exposure light, the reduction of running cost is a problem.
In the observation by the first optical system, it is not necessary to use the exposure light, so that the running cost can be reduced. (4) When observing the first alignment mark and the first fiducial mark, light having a wavelength different from that of the exposure light can be used. Therefore, an optical gas such as an excimer laser is used as the exposure light. Even when a light source that needs to be replaced is used, the volume of the portion to be replaced with nitrogen is reduced, so that the consumption flow rate of nitrogen decreases. Therefore, the running cost can be reduced. (5) Similarly, even when an exposure light source that needs to replace the optical system portion with an inert gas such as nitrogen is used, the nitrogen consumption flow rate is reduced, so that the nitrogen replacement time is shortened. Can be.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a projection exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a detailed view showing a part of the apparatus of FIG. 1 in detail.

FIG. 3 is another detailed view showing a part of the apparatus of FIG. 1 in detail.

FIG. 4 is an isometric view showing a configuration of a TTR microscope of the apparatus of FIG.

FIG. 5 is an explanatory diagram at the time of baseline measurement according to a conventional example.

FIG. 6 is an explanatory diagram of mark arrangement on a reticle.

FIG. 7 is an isometric view showing a configuration of a conventional TTR microscope.

FIG. 8 is a flowchart illustrating a device manufacturing example using the exposure apparatus according to the present invention.

FIG. 9 is a flowchart showing a detailed flow of a wafer process in FIG. 8;

[Explanation of symbols]

1: excimer laser, 2: divergent lens, 3, 5, 8: lens, 4, 6, 9, 11: bending mirror, 10: fly-eye lens, 12: condenser lens, 13: reticle, 13a, 13b: Alignment mark, 13a ', 1
3b ': left alignment mark, 14: projection lens, 1
5: Stage, 16: Interferometer, 17: Stage drive, 18: Reference mark, 18b, 18c: Mark, 1
9: wafer, 19a: wafer alignment mark, 20:
TTR microscope, 20a: lens, 20b: half mirror, 20c: objective lens, 20d: mirror, 20e: lens, 20f: camera, 20g: processing device, 21 and 21
2: condensing lens, 23: fiber, 25: TTL off-axis microscope, 25a: lens, 25b: half mirror, 25c: objective lens, 25d: mirror, 25dd:
Position where 25d mirror observes mark 13b, 25e:
Lens, 25f: camera, 25g: processing device, 25h:
Reference mark, 25i: lens, 26: light source, 27: fiber, 30: illumination unit, 30a: light source, 30b: fiber, 30c: lens, 30d: mirror, 30e: reference mark for reticle positioning, 40: reticle stage Interferometer, 41: reticle stage driving device, 50: control device, 71, 73, 74, 75: mirror, 72: relay lens, 401, 403, 405: mirror, 404: relay lens, 406: elector lens, 407: camera,
601: an area through which the exposure light can pass through the projection lens;
2: Pattern on reticle.

Claims (7)

[Claims] An original stage; a pattern to be exposed and held on the original stage, and first and second patterns;
A first fiducial mark for aligning the original having the alignment marks of the above with the apparatus; a substrate stage; and projecting the pattern of the original onto a photosensitive substrate held on the substrate stage. A projection optical system; a second reference mark provided on the substrate stage; a TTL off-axis microscope for observing the substrate or the second reference mark via the projection optical system; and a TTL off-axis microscope A third reference mark provided in or on the optical path thereof; and detecting a relative position between the substrate or the second reference mark and the third reference mark based on an observation result by the TTL off-axis microscope. First mark position detecting means; simultaneously observing the first alignment mark and the first reference mark, and performing the second alignment And a TTR microscope for observing the workpiece and the substrate or the second reference mark at the same time, and for the substrate or the second reference mark via the projection optical system; And a second mark position detecting means for detecting a relative position between the second alignment mark and the first reference mark and a relative position between the second alignment mark and the substrate or the second reference mark. Projection exposure for driving the original plate stage and the substrate stage based on the detection results of the first and second position detecting means to align the original plate and the substrate, and exposing the pattern of the original plate onto the substrate In the apparatus, the TTR microscope includes a first optical system that simultaneously observes the first alignment mark and the first reference mark; Projection exposure apparatus characterized by comprising a second optical system for observing the second alignment mark and the substrate or the second reference mark simultaneously. 2. The projection exposure apparatus according to claim 1, wherein the illumination light used in the first optical system and the illumination light used in the second optical system have different wavelengths. 3. The first optical system and the second optical system can be driven integrally, and the positional relationship between the observation positions of each optical system is determined by the distance between the first and second alignment marks. 3. The projection exposure apparatus according to claim 1, wherein the positional relationship is the same as the positional relationship, or the positional relationship allows the first and second alignment marks to be observed simultaneously. 4. The illumination light used in the second optical system is exposure light, and the illumination light used in the first optical system is non-exposure light. 1
Item 6. The projection exposure apparatus according to Item 1. 5. An illumination device for emitting illumination light used in the first optical system from below the first reference mark, wherein the first reference mark is located below the original plate,
The said 1st optical system is for observing the said 1st alignment mark and the said 1st reference mark illuminated by the said illuminating means simultaneously from the said original plate, The said 1st characterized by the above-mentioned. 5. The projection exposure apparatus according to claim 4. 6. An original plate stage; a pattern to be exposed and held on the original plate stage;
A first fiducial mark for aligning the original having the alignment marks of the above with the apparatus; a substrate stage; and projecting the pattern of the original onto a photosensitive substrate held on the substrate stage. A projection optical system; a second reference mark provided on the substrate stage; a TTL off-axis microscope for observing the substrate or the second reference mark via the projection optical system; and a TTL off-axis microscope A third reference mark provided in or on the optical path thereof; and detecting a relative position between the substrate or the second reference mark and the third reference mark based on an observation result by the TTL off-axis microscope. First mark position detecting means; simultaneously observing the first alignment mark and the first reference mark, and performing the second alignment And a TTR microscope for observing the workpiece and the substrate or the second reference mark at the same time, and for the substrate or the second reference mark via the projection optical system; And a second mark position detecting means for detecting a relative position between the second alignment mark and the first reference mark and a relative position between the second alignment mark and the substrate or the second reference mark. A first optical system for simultaneously observing the first alignment mark and the first reference mark; and a second system of the second alignment mark and the substrate or Second
Using a projection exposure apparatus having a second optical system for simultaneously observing the reference mark, and driving the original plate stage and the substrate stage based on the detection results obtained by the first and second position detecting means. Align the original plate and the substrate,
A method for manufacturing a device, comprising exposing the pattern of the original plate onto the substrate. 7. The first alignment mark and the first reference mark are simultaneously observed by the TTR microscope, and based on a result of the observation, the first alignment mark and the first reference mark are compared with each other. The relative position is detected by the second mark detection means, and based on the detection result, the original plate stage is moved to position the original plate with respect to the first reference mark, and then the TTR microscope The second alignment mark and the second reference mark are simultaneously observed, and the relative position between the second alignment mark and the second reference mark is detected based on the observation result. Means for moving the substrate stage based on the detection result, aligning the substrate stage, and then using the TTL off-axis microscope to detect the position of the second substrate. The quasi-mark and the third fiducial mark are observed, and based on the observation result, the second fiducial mark and the third fiducial mark are detected by the second mark position detecting means.
7. The device manufacturing method according to claim 6, wherein the relative position with respect to the reference mark is detected, and the exposure is performed in consideration of the detection result.