JP2002151377A - Projection aligner, projection aligning method, device- manufacturing method, and maintenance method for semiconductor manufacturing factory, and the projection aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate downtime of a device, caused by the processes of printing to and developing a pilot wafer by minimizing the number of the processes. SOLUTION: A device for projecting and aligning a pattern on the first substrate to the second substrate via a projecting optical system is provided with a detecting optical system for detecting the position of the second substrate via the first substrate and the projecting optical system, a detecting optical system for detecting the position in the direction of the optical axis of the projecting optical system of the first substrate, and means for controlling the focusing position, when the pattern on the first substrate is projected to the second substrate, based on the detection result of both the substrates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of semiconductor device manufacturing, and more particularly to a stepper, a scanner and a projection exposure apparatus for projecting a circuit pattern on a reticle onto a semiconductor wafer surface by repeatedly reducing and projecting the same. The present invention relates to an exposure method, a device manufacturing method, a semiconductor manufacturing factory, and a maintenance method of a projection exposure apparatus, and particularly to a projection exposure apparatus having an automatic focus adjustment function and a method thereof.

[0002]

2. Description of the Related Art In recent years, semiconductor devices, LSI devices, super LS
Due to the demand for finer patterns and higher integration of I-elements,
The projection exposure apparatus requires an imaging optical system having a high resolution. Accompanying this, the NA of the imaging optical system has been increased, and the depth of focus of the imaging optical system has become smaller. Therefore, in a projection exposure apparatus, it is necessary to match the wafer surface with the focal plane of the imaging optical system. An effective autofocusing method is an important theme.

In a projection exposure apparatus, the focus position of the exposure apparatus fluctuates due to a change in temperature around the projection optical system, a change in atmospheric pressure, a rise in temperature due to a light beam applied to the projection optical system, and the like. There is a need. As means for detecting the focus position for this correction, a so-called TTL that detects the focus position through a projection optical system is used.
There is a method called auto focus (TTLAF).

FIG. 11 is a schematic view of a projection exposure apparatus having a TTL autofocus function disclosed in Japanese Patent Application Laid-Open No. 9-260269. In FIG. 11, reference numeral 106 denotes a reticle, which is held on a reticle stage 107. The circuit pattern on the reticle 106 is subjected to reduction projection exposure on the wafer 112 on the xyz stage 111 by the reduction projection lens 109. On the other hand, at a position adjacent to the wafer 112, a reference plane mirror 113 is disposed at a position substantially coincident with the upper surface of the wafer 112 with respect to the focus direction of the reduction projection optical system, and a stage having a vertical and horizontal pattern shown in FIG. A reference mark (focus detection mark) 113a is formed.

The xyz stage 111 is movable in the optical axis direction (z direction) of the reduction projection lens 109 and in a plane (x, y) orthogonal to this direction, and can be rotated around the optical axis.

The reticle 106 includes elements 101 to 1 shown in FIG.
The illumination optical system denoted by 05 illuminates the screen area where the circuit pattern is transferred.

The elements 110, 113 and 114 form a well-known off-axis autofocus optical system. The light flux of the non-exposure light emitted from the light projecting optical system 110 is condensed and reflected at a point on the reference plane mirror 113, and enters the detection optical system 114.

Although not shown in the drawing, a light detecting element for position detection is provided in the detection optical system 114, and the light receiving element for position detection and the reflection point of the light beam on the reference plane mirror 113 are arranged to be conjugate. The positional deviation of the reference plane mirror 113 in the optical axis direction of the reduction projection lens 109 is measured as the positional deviation of the incident light beam on the position detecting light receiving element in the detection optical system 114.

The displacement of the reference plane mirror 113 from a predetermined reference plane measured by the detection optical system 114 is as follows:
The signal is transmitted to the auto focus control system 132. The auto-focus control system 132 gives a movement instruction in the z-direction to a stage drive system 133 that drives the xyz stage 111. When the focus position is detected by TTL by the detection optical system 127, the reference plane mirror 113 is driven in the optical axis direction of the reduction projection lens 109 near a predetermined reference position. The position control of the wafer 112 during exposure (the wafer 112 is arranged at the position of the reference plane mirror 113 in FIG. 11) is also performed by the autofocus control system 132.

Next, the focus position detecting optical system of the reduction projection lens 109 will be described. Reference numeral 127 denotes a TTL autofocus detection optical system.
3, 124, 140, and 141. Fiber 1
The illumination light beam emitted from 40 passes through the half mirror 141 and is condensed near the reticle 106 via the objective lens 124 and the mirror 123. As shown in FIG. 12, on the reticle 106, a light-transmitting portion (window cutout) 108 having a predetermined size is provided at a position RW outside the actual element region.

After passing through the window opening 108, the illuminating light beam passes through a reduction projection lens 109 and is used as a reference plane mirror 11
3 is focused. A focus detection mark 113a as shown in FIG. 13 is provided on the surface of the reference plane mirror 113. Then, the reflected light from the reference plane mirror 113 returns to the original optical path, passes through the reduction projection lens 109, the window opening section 108, the mirror 123, and the objective lens 124 in order.
The light is reflected by the half mirror 141 and is incident on the position sensor 126.

This reference plane mirror 113
2 is arranged on the same wafer stage 111 and is fixed on a focus surface which is substantially coincident with the wafer 112. The focus position of each of the wafer surface 112a and the stage reference mark 113a or the focus offset amount between both surfaces is managed by the auto focus detection system 131. Thus, focusing on the reference plane mirror 113 is performed in accordance with the following procedure, and focusing on the actual wafer is automatically performed only by giving a predetermined offset amount.

[0013] As shown in FIG.
The stage reference mark 113a on 3 is formed of a vertical and horizontal pattern having a predetermined line width. Focus detection mark 1
The light beam emitted from 13a returns to the forward path and reaches the objective lens 124. The light beam that has passed through the objective lens 124 is reflected by the half mirror 141, and forms an image on the sensor surface 126a of the position sensor 126. This position sensor 126
It may be a one-dimensional array sensor or a two-dimensional sensor represented by a CCD. Stage reference mark 113
Only one-way pattern (vertical or horizontal) corresponding to a
If the focus detection is sufficient, a one-dimensional array sensor is sufficient, and if focus detection of a two-way pattern (simultaneous vertical and horizontal lines) is required, a two-dimensional array sensor is used.

The reference plane mirror surface 113 is swung in the optical axis direction of the reduction projection lens 109 in order to obtain an optimum focus plane. At this time, on the position sensor 126, information that the focus state of the stage reference mark 113a has changed correspondingly is obtained.

As to which kind of focus information is used as a signal, for example, there is a method in which the light intensity contrast of the focus detection mark is highest at the best focus position, and decreases at the defocus position. Alternatively, the differential value (corresponding to the tilt angle) of the light profile of the focus detection mark may be used as the evaluation amount. These signal processings are performed by the image signal analysis circuit 147. As is clear from the above description, in the projection exposure apparatus shown in FIG. 11, the outward path is the illumination optical path, and the information on the focus is obtained through only one optical path on the return path.

In the TTL autofocus method as the prior art shown here, the pattern on the reticle 106 is first actually exposed and transferred to the wafer 112,
The wafer surface 112 with respect to the best image formation surface of the projection lens 109
a first step of focusing a, a second step of detecting the best imaging position of the wafer surface 112a or an equivalent surface thereof by the TTL focus detection optical system 127 at approximately the same first time, In the middle or at a second time different from the first time, the wafer surface 112
a or a third step of detecting the optimum focus position of the equivalent surface by the detection optical system 127, and based on the detection result of the optimum focus surface obtained in the third step, the reticle surface 106a and the wafer A means for always correcting the surface 112a to the optimum focus state is used.

FIG. 14 is a flowchart showing a sequence of TTL autofocus detection in the prior art. In FIG. 14, first, reticle pattern surface 106
The focus of the detection optical system 127 is adjusted to a. This purpose is only for the purpose of preventing the measurement position from largely deviating from the measurement range. Originally, the reticle surface 106a and the wafer surface 112a are roughly focused beforehand. Therefore, if the reticle surface 106a and the sensor surface 126a are extremely displaced, the sensor surface 126a and the wafer surface 112a are greatly displaced as a result. As a result, the peak of the signal is lost. In such a case, focusing of the objective lens 124 is performed using the driving unit 148. One of the functions of the controller 146 is to judge the necessity of the operation. The controller 146 obtains the output of the image signal analyzer 147 and issues a command to the driving unit 148 of the objective lens 124.

Next, the focus origin is adjusted by burning the reticle 106 and the wafer 112. Specifically, a reticle pattern (for example, a resolution chart or an actual element pattern) is printed at a plurality of positions on the wafer 112 while changing the focus of the wafer surface 112a. Then, the wafer 112 is once developed, and a printed image is measured by means such as an SEM to determine an optimum focus plane.

On the other hand, at about the same time (meaning that the focus state of the apparatus does not change within a sufficiently short time), the above-described detection optical system 127 is used to send the stage reference mark 113a to the Z-axis of the wafer stage 111.
The focus measurement is repeated while changing the position in the direction (optical axis direction of the projection lens). Then, the optimal focus plane is automatically determined using the signal obtained by the position sensor 126.

When the optimum focus plane is determined, the information is input to the apparatus as a focus offset. This offset input means that the original point shift amount between the actual optimum exposure focus and the optimum focus surface promoted by the autofocus detection system 131 is corrected. Such origin search is first performed for each process, and is filed as a process offset.

Once the exposure of the actual wafer (process wafer) is started, the stage reference mark 113a is periodically sent between the actual wafers, and the focus is changed by the detection optical system 127 similarly to the above while changing the focus. Repeat measurement. Then, the optimum focus plane is automatically determined, and the amount of offset change from the initially determined focus origin is calculated. The wafer stage 111 is driven in the z direction by that value to bring the wafer surface 112a to the optimum focus surface of the projection lens 109. The above sequence is executed periodically or at a predetermined timing during exposure.

The position of the reference plane mirror 113 on the wafer stage 111 when the wafer 112 is positioned on the focus surface of the projection lens 109 (the position in the optical axis direction of the projection lens 109) is provided on the reference plane mirror 113. The image of the focus detection mark 113a is formed on the position sensor 126 of the detection optical system 127 via the projection lens 109,
The signal obtained by the position sensor 126 at this time is the focus position of the projection lens 109. At this time, the signals obtained by the off-axis auto focus detection systems 110, 114, and 132 are used as reference signals, that is, signals at the time of focusing.

When repeatedly exposing, the wafer 11 is exposed.
The positions of the two surfaces in the optical axis direction are detected using off-axis autofocus detection systems 110, 114, and 132, which are easy to detect, and based on the detection results, a stage drive system 133 is provided.
The wafer stage 111 is driven in the optical axis direction to perform focusing. The detection of the focus position by the detection optical system 127 is performed at predetermined time intervals.

[0024]

In the prior art described above, once the reticle is changed, the focus origin is determined for each reticle by burning (first step), and the TTL of the stage reference mark is approximately at the same time. It is necessary to perform focus measurement (second step) and obtain a correlation between the two.

Hereinafter, the reason will be described. (1) In a projection exposure apparatus, projection exposure is performed by a change in temperature around the projection optical system, a change in atmospheric pressure, a rise in temperature due to a light beam applied to the projection optical system, or a rise in temperature due to heat generation in an apparatus including the projection optical system. The focus position of the device fluctuates. The time-dependent change as this device occurs equally in the TTL focus measurement performed in the first step and the second step, so that it is not necessary to take a correlation.

(2) However, since the reticle surface accuracy varies from reticle to reticle, the surface accuracy of the effective patterning region is further deteriorated due to the fact that suction is performed on the reticle stage particularly at the periphery of the reticle where the surface accuracy deteriorates. In some cases. This error factor is measured in the first step, but cannot be measured in the second step because it does not depend on the position of the reticle pattern surface 106a. Therefore, in consideration of the influence of the reticle surface accuracy, it is necessary to correlate the two for each reticle.

(3) Further, there is a problem of a reticle thickness error. In the first step, the thickness error of the reticle 106 is not affected. However, in the second step, since the detection optical system 127 observes the stage reference mark 113a through the reticle 106, the detection optical system 127 is affected by the thickness error of the reticle 106, and the TT of the stage reference mark 113a is
The L focus measurement value changes. According to the SEMI standard, for example, the thickness for a 6-inch reticle is 6.
35 ± 0.10 mm. 6.35 mm of reticle A with a reference thickness of 6.35 mm and reticle B with a thickness of 6.25 mm
Compare the equivalent optical path lengths in air. Assuming that the refractive index at the exposure wavelength of the reticle (the observation wavelength of the detection optical system 127) is 1.51, reticle A: 6.35 / 1.51 = 4.2053 mm reticle B: 6.25 / 1.51 + 0.10 = 4.23
At 91 mm 2, the difference between the two is 0.0338 mm. This amount is
This corresponds to a focusing difference between the reticle A and the reticle B on the reticle equivalent surface by the objective lens 24. Assuming that the reduction ratio of the reduction projection lens 109 is 1/5, the focus shift in the optical axis direction is proportional to the square of the magnification. Therefore, the focus shift of 0.0388 mm on the reticle surface is 1/25 when considered on the wafer surface, and the focus of 1.35 μm is shifted on the wafer surface. This amount is unacceptable in view of the requirement that the wafer be focused at about 0.10 μm during recent exposure.

In view of the above, it can be said that it is essential to correlate the first step and the second step with the factors (2) and (3). If the correlation value is to be managed as an offset for each reticle, the first step and the second step may be performed once for each reticle and the offset may be input, but generally the number of reticles becomes enormous. Therefore, the load of finding the origin by the baking in the first process is large, and the downtime of the apparatus is prolonged.

An object of the present invention is to solve the above-mentioned problems of the prior art and to minimize the number of times of baking development and development processing on a pilot wafer, thereby eliminating downtime of the apparatus due to these processings. It is in.

[0030]

In order to achieve the above object, an exposure apparatus according to the present invention comprises: (1-1) a pattern on a first substrate on a second substrate via a projection optical system; In a projection exposure apparatus, a detection optical system for detecting a position of a second substrate via a first substrate and a projection optical system, and a detection optical system for detecting a position of the first substrate in an optical axis direction of the projection optical system And a means for controlling a focus position when projecting and exposing the first substrate onto the second substrate based on the detection results of both substrates.

Further, specifically, the above object can be achieved by, for example, the following configuration and operation. (1-1-1) In the detection optical system that detects the position of the first substrate, the lens in the detection optical system is sequentially moved in the optical axis direction, so that the position on the position detection sensor in the optical system is changed. By changing the imaging state, the position of the first substrate can be detected. (1-1-2) In the detection optical system for detecting the position of the second substrate, the position of the second substrate in the direction of the optical axis of the projection optical system is sequentially moved, so that the position in the detection optical system is obtained. By changing the imaging state on the detection sensor, the position of the second substrate can be detected. (1-1-3) At least a part of the detection optical system for detecting the position of the first substrate and the detection optical system for detecting the position of the second substrate are the same optical system, and A dedicated mark for focus detection is provided on the substrate and the second substrate, and on a position detection sensor in the detection optical system that detects the position of the second substrate via the first substrate and the projection optical system. By configuring so that both marks form an image, a user can visually confirm the effects of the present invention. (1-1-4) The detection optical system that detects the positions of the first substrate and the second substrate performs position measurement in the optical axis direction of the projection optical system and also performs position measurement in the direction orthogonal to the optical axis. It may be something. That is, an alignment optical system for aligning the first substrate and the second substrate, or a part thereof, may be used as the detection optical system of the present invention. (1-1-5) Further, for example, a configuration may be employed in which the position of the projection optical system in the optical axis direction is detected using an alignment mark in a peripheral region on the first substrate. Is measured through a window cutout on the first substrate. (1-1-6) In (1-1-5), at least a part of the optical system for detecting the position of the first substrate aligns the first substrate with the reference mark held on the apparatus. May be used as an optical system for alignment. In this case,
An optical system for detecting the position of the second substrate is provided separately from another optical system.

(1-2-1) Further, a display, a network interface,
By providing a computer that executes network software, it becomes possible to perform data communication of maintenance information of the exposure apparatus via a computer network. The network software is connected to an external network of a factory where the exposure apparatus is installed, and provides a user interface on a display for accessing a maintenance database provided by an exposure apparatus vendor or a user. To obtain information from the database.

The exposure method according to the present invention may further comprise the following steps: (2-1) A method of projecting and exposing a pattern on a first substrate onto a second substrate via a projection optical system. A first step of detecting the position in the optical axis direction by a detection optical system, a second step of detecting the position of a second substrate by a detection optical system via a first substrate and a projection optical system, A third step of controlling a focus position when projecting and exposing the first substrate on the second substrate based on the detection result.

(2-1-1) In the first step in (2-1), after the focus measurement of the pattern on the first substrate by the detection optical system, the focus of the position sensor in the detection optical system is changed to the first substrate. It is preferable to focus on the above pattern. (2-1-2) Here, immediately after the first substrate is replaced, the pattern on the first substrate is usually changed to the second process by following the procedure of the first step, the second step, and the third step. Projection exposure on the substrate, but depending on a predetermined time or the number of the second substrate, without performing the first step or the first and second steps together, on the second substrate The control of the focus position at the time of the projection exposure may be performed based on the focus position on the second substrate immediately before. Thereby, the total throughput of the projection exposure processing is improved.

Further, the device manufacturing method according to the present invention comprises: (2-2-1) a step of installing a group of manufacturing apparatuses for various processes including an exposure apparatus in a semiconductor manufacturing plant; Manufacturing a semiconductor device by a process. A step of connecting a group of manufacturing apparatuses via a local area network;
Data communication between at least one manufacturing apparatus group and the local area network and an external network outside the semiconductor manufacturing plant. Also, a database provided by an exposure apparatus vendor or user is accessed via an external network to obtain maintenance information of the manufacturing apparatus by data communication, or an external network is connected to a semiconductor manufacturing factory different from a semiconductor manufacturing factory. The production management may be performed by data communication via the PC.

The semiconductor manufacturing plant according to the present invention includes: (3-1) a group of manufacturing apparatuses for various processes including the above-described exposure apparatus of the present invention, a local area network connecting the group of manufacturing apparatuses, and a local area network. It has a gateway that allows access from the network to an external network outside the factory, and enables data communication of information on at least one of the manufacturing equipment groups.

The method for maintaining an exposure apparatus according to the present invention includes the following steps: (4-1) a step in which a vendor or user of the exposure apparatus provides a maintenance database connected to an external network of the semiconductor manufacturing plant; , A step of permitting access to the maintenance database via an external network, and a step of transmitting maintenance information stored in the maintenance database to the semiconductor manufacturing factory via the external network.

[0038]

(Embodiment 1) FIG. 1 is a schematic view showing a main part of a projection exposure apparatus according to Embodiment 1 of the present invention. This embodiment shows a schematic configuration of a TTLAF system using a reference plane mirror on a wafer stage in a sequential exposure system (stepper). In FIG. 1, reference numeral 1 denotes a reticle, which is held on a reticle stage 2. On the reticle 1, there is a focus detection mark RW as shown in FIG. The circuit pattern on the reticle 1 is imaged by the projection lens 3 on the wafer 6 on the xyz stage 8 at a predetermined reduction rate, and exposure is performed. At a position adjacent to the wafer 6, a reference plane mirror 7 whose mirror surface almost coincides with the upper surface of the wafer 6 is arranged. Reference plane mirror 7
Is provided with a stage reference mark (focus detection mark) 7a as shown in FIG.

The xyz stage 8 is movable in the optical axis direction (z direction) of the reduction projection lens 3 and in a plane (x, y) orthogonal to this direction, and can be rotated around the optical axis. .

The reticle 1 is illuminated by an exposure illumination system (not shown) in a screen area where a circuit pattern is transferred.

The mark elements 4, 7 and 5 form a well-known off-axis surface position detecting optical system. The luminous flux of the non-exposure light emitted from the surface position detection light projecting system 4 is condensed and reflected on a point on the reference plane mirror 7 and enters the surface position detection light receiving system 5.

Although not shown, there is a position detecting light receiving element in the surface position detecting light receiving system 5, and the position detecting light receiving element and the reflection point of the light beam on the reference plane mirror 7 are arranged to be conjugate. The positional deviation of the reference plane mirror 7 in the optical axis direction of the reduction projection lens 3 is measured as the positional deviation of the incident light beam on the position detecting light receiving element in the surface position detecting light receiving system 5.

The displacement of the reference plane mirror 7 from the predetermined reference plane measured by the surface position detection light receiving system 5 is transmitted to the surface position detection system 61 and the autofocus control system 71. The autofocus control system 71 gives an instruction for movement in the z direction to the stage drive system 51 that drives the xyz stage 8.

When the focus position is detected by the TTL by the observation microscope 41 serving as a detection optical system, the reference plane mirror 7 is driven in the optical axis direction of the reduction projection lens 3 near a predetermined reference position. The position control of the wafer 6 at the time of exposure (the wafer 6 is arranged at the position of the reference plane mirror 7 in FIG. 1) is also performed by the autofocus control system 71.

Next, in the present embodiment, first, the focus state of the reticle 1 surface is detected, the focus of the observation microscope 41 is adjusted with respect to the reticle 1, and then the focus state of the wafer 6 is detected. The focus position of the lens 3 is detected and the wafer 6 is exposed. The details will be described below.

An observation microscope 41 detects the focus on the reticle surface and the focus on the wafer surface by TTL. Although the observation microscope 41 has a left-right two-eye configuration, the position of the objective lens 12 may be left-right symmetric or not, and may be a left-right one-eye configuration.

An illumination light beam emitted from a fiber 21 guided from an exposure illumination system (not shown) passes through a beam splitter 13 via a lens 22, and passes through an objective lens 12 and a mirror 11 to a focus detection mark RW on the reticle 1. The area is Koehler-illuminated. The objective lens 12 and the mirror 11 can be integrally moved in the x direction by an objective lens driving system 52, and the observation microscope 41 can be moved by an observation microscope driving system 54.
The whole can be moved in the y direction. Therefore, the focus detection mark RW may be at a fixed position somewhere outside the maximum real element region, or may be arranged with a light-shielding band interposed therebetween so as not to be transferred onto the wafer 6 outside the real element region. When the objective lens 12 and the mirror 11 are moved in the x direction, the light flux between the objective lens 12 and the relay lens 14 is a parallel light so that the focus of the position sensor 18 does not change.

As shown in FIG. 2, the focus detection mark RW is formed at a position outside the actual element area by a pattern 1 having a predetermined line width.
a and a light-transmitting portion (window-less portion) 1b of a predetermined size
, And the size of the field of view of the objective lens 12 includes both.

The light reflected from the pattern 1 a passes through the mirror 11, the objective lens 12, the beam splitter 13, the relay lens 14, the mirror 15, and combines the left and right fields of view with the roof prism 16. An image is formed on the sensor 18.

First, in order to focus the observation microscope 41 on the reticle, the relay lens driving system 53
The position sensor 18 obtains information depending on the focus state by changing the position of the relay lens 14 in the optical axis direction.
The position sensor 18 may be a one-dimensional array sensor or a two-dimensional sensor represented by a CCD.
A one-dimensional array sensor is sufficient if focus detection of only one direction pattern (vertical line or horizontal line) is sufficient, and focus detection of two direction patterns (simultaneous vertical line and horizontal line) corresponding to pattern 1a is required. For example, a two-dimensional array sensor is used.

In this embodiment, there is no particular limitation on what kind of focus information is used as a signal. For example, there is a method in which the light intensity contrast of a focus detection mark such as the mark RW, 7a is highest at the best focus position, and decreases at the defocus position. FIG. 5 shows the relationship between the light intensity contrast and the focus when the relay lens 14 is swung in the optical axis direction at this time. With respect to this light intensity contrast curve, a method of obtaining a peak position by approximating the curve with a quadratic curve, a method of cutting the light intensity contrast curve at a certain slice level and obtaining a middle point where the curve intersects, or the like can be considered. As another method, a differential value (corresponding to the inclination angle) of the light profile of the focus detection mark may be used as the evaluation amount. These signal processes are performed by the TTL focus detection system 62.

After detecting the focus state with respect to the pattern 1a, the position of the relay lens 14 is changed to the relay lens driving system 5
The focus is changed to the best focus position on the left and right separately by 3, and the focusing of the observation microscope 41 on the reticle 1 ends.

On the other hand, the illumination light beam illuminates the reference plane mirror 7 via the reduction projection lens 3 after passing through the window cutout 1b. A stage reference mark (focus detection mark) 7 as shown in FIG.
a are provided at two places on the left and right. The interval between the two stage reference marks on the left and right is a position corresponding to the focus detection mark RW on the reticle 1. Then, the reflected light from the reference plane mirror 7 returns to the original optical path, and the reduction projection lens 3, the window opening 1 b, the mirror 11, the objective lens 12
, Is reflected by the beam splitter 13, passes through the relay lens 14, and combines the left and right visual fields with the roof prism 16.
The image is further enlarged by the elector 17 and is incident on the position sensor 18 to obtain an image of the focus detection mark 7a and the RW as shown in FIG.

The reference plane mirror surface 7 is swung in the optical axis direction of the reduction projection lens 3 in order to obtain the optimum focus plane. At that time, information indicating that the focus state of the stage reference mark 7a has changed is obtained on the position sensor 18 correspondingly. This method is the same as that when the observation microscope 41 is focused on the pattern 1a.

The reference plane mirror 7 is arranged on the same wafer stage 8 as the wafer 6, and
It is fixed on the focus plane which is almost coincident. The focus position of each of the wafer surface 6a and the stage reference mark 7a surface or the focus offset amount between both surfaces is managed by the auto focus control system 71. Thus, in the subsequent procedure, focusing on the reference plane mirror 7 and focusing on the actual wafer are automatically performed only by giving a predetermined offset amount.

As is clear from the above description, in the projection exposure apparatus shown in FIG. 1, the dwelling path to the reference plane mirror surface 7 is an illumination light path, and the information regarding focus is obtained by only one light path on the return path. .

In the TTL autofocus method according to this embodiment, the observation microscope 41 first detects the focus state of the focus detection mark 1a on the reticle 1, and the focus of the focus detection mark 1a is adjusted based on the detection result. A first step of changing the position of the relay lens 14 in the optical axis direction so as to be the best on the sensor 18, and the observation microscope 41 detects the best imaging position on the wafer surface 6a or its equivalent surface (for example, 7a). And a means for constantly correcting the reticle surface and the wafer surface to an optimum focus state based on the detection result of the optimum focus surface obtained in the second process. FIG. 6 is a flowchart illustrating a TTL autofocus detection sequence according to the present embodiment.

Using the flowchart of FIG. 6, TTLA
The F detection step will be described. <First Step> First, the position of the relay lens 14 in the optical axis direction is sequentially moved by the relay lens driving system 53, and the focus measurement is repeated by the observation microscope 41. Then, using the signal obtained by the position sensor 18, the optimum focus position for the focus detection mark 1 a is obtained, and the position of the relay lens 14 is moved to the optimum focus position by the relay lens drive system 53.

<Second Step> Next, the above-mentioned observation microscope 41
And focus measurement is repeated while the position of the wafer stage 8 in the z direction (the optical axis direction of the projection lens 3) is changed by sending the stage reference mark 7a. Then, using the signal obtained by the position sensor 18, the stage reference mark 7
The optimum TTL focus plane for a is automatically determined.

<Test Wafer Exposure> Further, at about the same time as the first step and the second step, an actual pattern is exposed on a test wafer to determine an optimum focus plane, as has been conventionally performed. Keep it. The difference between the two is input to the apparatus as a focus offset. This offset means that the origin shift amount between the actual optimum exposure focus and the optimum focus surface promoted by the TTL focus detection system 62 is corrected. Since the TTL focus detection system 62 detects the origin shift amount at two image heights, if the reduction lens has a curvature of field, there will be a difference from the optimal exposure focus determined over the entire exposure area. And so on. It also occurs due to the flatness error of the reference plane mirror. However, since the origin shift amount does not depend on the reticle and the process, it does not change once the correlation between them is obtained. This is a decisive difference from the prior art.

<Third Step> Once the exposure of the process wafer has started, the stage reference mark 7a is periodically sent between the actual wafers while changing the focus thereof.
Similar to the above, the focus measurement is repeated by the TTL focus detection system 62. At this time, focusing on the focus detection mark 1a on the reticle 1 is not necessarily required. The position of the relay lens 14 only needs to be maintained after focusing on the first focus detection mark 1a. If necessary, the position may be stored and the relay lens 14 may be driven to the position before the focus measurement of the stage reference mark 7a.
As a method of detecting the position of the relay lens, there is a method of measuring the number of pulses of a pulse motor for driving the relay lens in the optical axis direction or measuring the position of the relay lens with an external sensor. Then, the optimum focus plane is automatically determined, and the amount of offset change from the initially determined focus origin is calculated. The wafer stage 8 is driven in the z direction by that value to bring the wafer surface 6a to the optimum focus surface of the projection lens 3.
The above sequence is executed periodically or at a predetermined timing during exposure.

As described above, in this embodiment, the projection lens 3
The position of the reference plane mirror 7 on the wafer stage 8 (the position in the optical axis direction of the projection lens 3) on the wafer stage 8 when the wafer 6 is positioned on the focal plane of the projection lens is an image of the stage reference mark 7a provided on the reference plane mirror 7. An image is formed on the position sensor 18 of the observation microscope 41 via the lens 3, and the signal obtained by the position sensor 18 at this time is used as the focus position of the projection lens 3.
At this time, the signals obtained by the off-axis surface position detecting optical systems 4, 7, and 5 are used as reference signals, that is, signals when focus is achieved.

During repeated exposure, the position of the surface of the wafer 6 in the direction of the optical axis is detected by using the surface position detecting optical systems 4, 7 and 5 which are easy to detect. The wafer stage 8 is driven in the optical axis direction to perform focusing. The detection of the focus position with respect to the stage reference mark 7a by the observation microscope 41 is performed at predetermined time intervals.

(Embodiment 2) FIG. 7 shows a projection exposure apparatus according to the present invention.
It is a principal part schematic diagram which shows 2nd Embodiment of an installation. Shown in the figure
The difference between the apparatus shown in FIG. 1 and the apparatus shown in FIG.
Since the mark detection mark RW is just a window,
The focus of the observation microscope 41 on the
RA for tickle alignment_U Using the mark 29a
Are different. The details will be described below. FIG.
, From an exposure light source (not shown) or a separately provided light source
The luminous flux emitted from the light-guiding fiber 25 is collected by the condenser lens 2.
6, reticle fiducial mark 2 reflected by mirror 27
RA on 8_D Mark 28a and RA on reticle 1_U Mar
The lamp 29a is illuminated. In the case of another light source, the wavelength
Not only the wavelength but also if the aberration is corrected by the observation microscope 41
It is good The reticle reference mark 28 is a stepper book.
It is held against the body and is several tens of
μm gap for reticle alignment
It is used for RA on reticle 1 in FIG. _U 
Below the mark 29a, the reticle reference mark in FIG.
RA on 28_D There is a mark 28a, and the relative position of both
Reticle alignment is performed by matching. Objective
The lens 12 and the mirror 11 are connected to an objective lens driving system 52 and
By the observation microscope drive system 54, RA_D Mark 28a and R
A_U Move to a position where you can observe the mark 29a in advance.
It is. RA_D Mark 28a and RA_U Through the mark 29a
The luminous flux that has passed is placed on the position sensor 18 as in the first embodiment.
Form an image.

Next, a specific operation of the TTL autofocus method according to the present embodiment will be described. RA _D on <First Step> First reticle reference mark 28
Mark 28a (or RA _U mark 29 on reticle 1)
With respect to a), focus measurement is repeated while the relay lens drive system 53 moves the relay lens 14 in the optical axis direction. And from the signals obtained by the position sensor 18, so that the focus of the RA _D mark 28a on the reticle reference mark 28 (or RA _U mark 29a on the reticle 1) is optimum on the position sensor 18, a relay lens drive system 53
Changes the position of the relay lens 14 in the optical axis direction.

<Second Step> Further, the objective lens 12 and the mirror 11 are moved by the objective lens drive system 52 and the observation microscope drive system 54 to the windowless portion RW where there is no pattern on the reticle whose coordinates have been confirmed and set in advance. I do. As in the first embodiment, the focus measurement is repeated using the observation microscope 41 while sending the stage reference mark 7a and changing the position of the wafer stage 8 in the z direction (the optical axis direction of the projection lens). Then, using the signal obtained by the position sensor 18, the optimum focus plane for the stage reference mark 7a is automatically determined.

[0067] Here, RA _D on the reticle reference mark 28
When the mark 28a is used, since the gap between the reticle 1 and the reticle 1 is several tens μm, the focus of the observation microscope 41 is shifted from the reticle 1. However, this shift is not a problem because the actual exposure does not depend on the reticle and only needs to take a focus offset once.

Although the TTL autofocus method has been described above, the alignment of the reticle 1 with respect to the reticle reference mark 28 can be performed before or after the first step.

(Embodiment 3) FIG. 10 is a schematic view showing a main part of a projection exposure apparatus according to a third embodiment of the present invention. In the third embodiment, the focusing on the pattern on the stage reference mark is the same as that in the second embodiment, but the focusing on the reticle reference mark 28 (or the mark on the reticle 1) uses another reticle alignment. Perform with a microscope.

In FIG. 10, the light source 25 is, for example, a light emitting diode, a laser diode or the like, and the wavelength does not need to be the exposure wavelength. Of course, as in the second embodiment,
Light may be guided from an exposure light source (not shown) by a fiber. Light emitted from the light source 25 passes through the condenser lens 26 and a mirror 27, illuminates the RA _D marks 28a and RA _U mark 29a on the reticle 1 on the reticle reference mark 28. The light passing therethrough is reflected by the mirror 81 and the objective lens 8.
2, relay lens 83, mirror 84 and erecta 85
To form an image on the position sensor 86.

Next, a specific operation of the TTL autofocus method according to the present embodiment will be described. RA _D on <First Step> First reticle reference mark 28
Mark 28a (or RA _U mark 29 on reticle 1)
With respect to a), focus measurement is repeated while the relay lens 83 is moved in the optical axis direction by the relay lens driving system 55. And from the signals obtained by the position sensor 86 determines the position where the focus of the RA _D mark 28a on the reticle reference mark 28 (or RA _U mark 29a on the reticle 1) is the best on the position sensor 86. Then, the shift of the best focus position from the reference position by the driving of the relay lens 83 is converted into a reticle surface or a wafer surface, and this time, the shift from the reference position of the relay lens 14 in the observation microscope 41 is converted. The position of the relay lens 14 is changed to the position by the relay lens driving system 53. Since the reference position of the relay lens 83 and the relay lens 14 are respectively separately with, in the observation microscope 41, RA _D mark 28a on the reticle reference mark 28
Against (or RA _U mark 29a on the reticle 1), does not mean that focus is achieved. However, the focus deviation from the best focus is not a problem because it becomes a constant focus offset at the time of exposure.

<Second Step> Further, the objective lens 12 and the mirror 11 are moved from the initial position where the exposure light is not blocked by the objective lens drive system 52 and the observation microscope drive system 54 onto the reticle whose coordinates have been previously confirmed and set. Move to windowless portion RW where there is no pattern. As in the first embodiment, the stage reference mark 7a is fed using the observation microscope 41 to move the wafer stage 8 in the z direction (the optical axis direction of the projection lens).
Focus measurement while changing the position of. Then, using the signal obtained by the position sensor 18, the optimum focus plane for the stage reference mark 7a is automatically determined.

[0073] Here, RA _D on the reticle reference mark 28
When the mark 28a is used, there is a gap of several tens of μm from the reticle 1. However, since the gap may be used as the focus offset as described in the second embodiment, there is no problem.

The relay lens driving systems 53 and 55 can be mechanically simplified by using a common one even if they are left and right individually. At this time, the objective lens 12
If the focal lengths of the relay lens 83 and the relay lens 14 are the same, the reference positions of the relay lens 83 and the relay lens 14 in the first step can be made common, and the stage driven by the relay lens can be used. The sensitivity of the focus shift of the reference mark becomes the same.
However, a constant focus offset is still required during exposure.

While the TTL autofocus method has been described above, the alignment of the reticle 1 with respect to the reticle reference mark 28 can be performed prior to or subsequent to the first step.

(Embodiment of Semiconductor Production System) Next, an example of a production system for semiconductor devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, etc.) will be described. This includes maintenance services such as troubleshooting and periodic maintenance of manufacturing equipment installed in semiconductor manufacturing plants, and software provision.
This is performed using a computer network outside the manufacturing factory.

FIG. 15 shows the whole system cut out from a certain angle. In the figure, reference numeral 301 denotes a vendor that supplies a semiconductor device manufacturing apparatus (apparatus supplier).
Is a business establishment. Examples of manufacturing equipment include semiconductor manufacturing equipment for various processes used in semiconductor manufacturing factories, for example, pre-processing equipment (lithography equipment such as exposure equipment, resist processing equipment, etching equipment, heat treatment equipment, film formation equipment, planarization). Equipment) and post-process equipment (assembly equipment, inspection equipment, etc.). In the business office 301, a host management system 3 that provides a maintenance database for manufacturing equipment
08, a plurality of operation terminal computers 310, and a local area network (LAN) 309 connecting these to construct an intranet. Host management system 3
Reference numeral 08 includes a gateway for connecting the LAN 309 to the Internet 305, which is an external network of the business office, and a security function for restricting external access.

On the other hand, reference numerals 302 to 304 denote manufacturing factories of a semiconductor manufacturer as users of the manufacturing apparatus. The manufacturing factories 302 to 304 may be factories belonging to different manufacturers, or factories belonging to the same manufacturer (for example, a factory for a pre-process, a factory for a post-process, etc.). In each of the factories 302 to 304, a plurality of manufacturing apparatuses 306, a local area network (LAN) 311 for connecting them and constructing an intranet, and a host management as a monitoring apparatus for monitoring the operation status of each manufacturing apparatus 306 are provided. A system 307 is provided. Each factory 30
The host management system 307 provided in each of the servers 2 to 304 includes:
A gateway is provided for connecting the LAN 311 in each factory to the Internet 305 which is an external network of the factory. This allows access to the host management system 308 on the vendor 301 side from the LAN 311 of each factory via the Internet 305, and access is permitted only to users limited by the security function of the host management system 308. More specifically, the factory notifies the vendor of status information indicating the operation status of each manufacturing apparatus 306 (for example, the symptom of the manufacturing apparatus in which a trouble has occurred) via the Internet 305, and responds to the notification. Response information (for example, information instructing a coping method for a trouble, software and data for coping), and maintenance information such as the latest software and help information can be received from the vendor. Each factory 30
For data communication between the vendors 2 to 304 and the vendor 301 and data communication on the LAN 311 in each factory, a communication protocol (TCP) generally used on the Internet is used.
/ IP) is used. Instead of using the Internet as an external network outside the factory, it is also possible to use a dedicated line network (such as ISDN) that cannot be accessed by a third party and has high security. Further, the host management system is not limited to the one provided by the vendor, and a user may construct a database and place the database on an external network, and permit a plurality of factories of the user to access the database.

FIG. 16 is a conceptual diagram showing the whole system of the present embodiment cut out from a different angle from FIG. In the above example, a plurality of user factories each having a manufacturing device and a management system of a vendor of the manufacturing device are connected via an external network, and the production management of each factory and at least one device are connected via the external network. The data of the manufacturing apparatus was communicated. In contrast, this example
A factory provided with manufacturing apparatuses of a plurality of vendors is connected to a management system of each vendor of the plurality of manufacturing apparatuses via an external network outside the factory, and data communication of maintenance information of each manufacturing apparatus is performed. In the figure, reference numeral 201 denotes a manufacturing factory of a manufacturing apparatus user (semiconductor device maker), and a manufacturing line for performing various processes, for example, an exposure apparatus 202, a resist processing apparatus 203, and a film forming apparatus 204 have been introduced. Although only one manufacturing factory 201 is illustrated in FIG. 16, a plurality of factories are actually networked similarly. Each device in the factory is connected by a LAN 206 to form an intranet, and the host management system 205 manages the operation of the production line. On the other hand, the exposure apparatus maker 210,
Resist processing equipment maker 220, film forming equipment maker 230
Each of the offices of such vendors (equipment suppliers) is provided with host management systems 211, 221, and 231 for performing remote maintenance of the supplied equipment, and as described above, the maintenance management database and the gateway of the external network are provided. Prepare. The host management system 205 that manages each device in the user's manufacturing factory and the management systems 211, 221, and 231 of the vendors of each device are connected by the Internet or the dedicated line network that is the external network 200. In this system, if a trouble occurs in any of a series of manufacturing equipment on the production line, the operation of the production line will be stopped,
Troubled equipment vendor Internet 20
By receiving the remote maintenance via the network 0, quick response is possible, and downtime of the production line can be minimized.

Each manufacturing apparatus installed in the semiconductor manufacturing factory has a display, a network interface, and a computer for executing network access software and apparatus operation software stored in a storage device. The storage device is a built-in memory, a hard disk, a network file server, or the like. The network access software includes a dedicated or general-purpose web browser, and provides, for example, a user interface having a screen as shown in FIG. 17 on a display. The operator who manages the manufacturing equipment at each factory refers to the screen and refers to the manufacturing equipment model (401), serial number (402), trouble subject (403), date of occurrence (404), and urgency (40).
5), symptom (406), coping method (407), course (40)
8) Input information such as in the input items on the screen. The input information is transmitted to the maintenance database via the Internet, and the resulting appropriate maintenance information is returned from the maintenance database and presented on the display. Further, the user interface provided by the web browser further realizes a hyperlink function (410 to 412) as shown in the figure, so that the operator can access more detailed information of each item or use the software library provided by the vendor for the manufacturing apparatus. The latest version of software to be extracted can be extracted, and an operation guide (help information) can be extracted for reference by a factory operator.

Next, a semiconductor device manufacturing process using the above-described production system will be described. FIG. 18 shows a flow of the whole semiconductor device manufacturing process.
In step 1 (circuit design), the circuit of the semiconductor device is designed. Step 2 is a process for making a mask on the basis of the circuit pattern design. On the other hand, in step 3 (wafer manufacturing), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and 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 assembly such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). Process. 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). The pre-process and the post-process are performed in separate dedicated factories, and maintenance is performed for each of these factories by the above-described remote maintenance system. Also, information for production management and equipment maintenance is communicated between the pre-process factory and the post-process factory via the Internet or a dedicated line network.

FIG. 19 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film 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 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto 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. Since the manufacturing equipment used in each process is maintained by the remote maintenance system described above, troubles can be prevented beforehand, and if troubles occur, quick recovery is possible. Productivity can be improved.

[0083]

As described above, according to the present invention,
This eliminates the need to perform the correlation between the actual exposure focus by the pilot wafer and the TTL autofocus measurement value, which had to be conventionally performed for each reticle, thereby eliminating downtime of the apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic view of a projection exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram of a reticle according to the first embodiment of the present invention.

FIG. 3 is a diagram of a reference plane mirror according to the first embodiment of the present invention.

FIG. 4 is an image observed by a position sensor according to the first embodiment of the present invention.

FIG. 5 is a correlation diagram of focus and contrast on a reticle surface or a wafer surface according to the first embodiment of the present invention.

FIG. 6 is a flowchart of a TTLAF operation according to the first embodiment of the present invention.

FIG. 7 is a schematic view of a projection exposure apparatus according to a second embodiment of the present invention.

FIG. 8 is a diagram of a reticle according to a second embodiment of the present invention.

FIG. 9 is a diagram of a reticle reference mark according to the second embodiment of the present invention.

FIG. 10 is a schematic view of a projection exposure apparatus according to a third embodiment of the present invention.

FIG. 11 is a schematic view of a projection exposure apparatus according to the related art.

FIG. 12 is a diagram of a reticle according to the related art.

FIG. 13 is a diagram of a reference plane mirror in the related art.

FIG. 14 is a flowchart of a TTLAF operation according to the related art.

FIG. 15 is a conceptual diagram of a semiconductor device production system viewed from a certain angle.

FIG. 16 is a conceptual diagram of a semiconductor device production system viewed from another angle.

FIG. 17 is a specific example of a user interface.

FIG. 18 is a diagram illustrating a flow of a device manufacturing process.

FIG. 19 is a diagram illustrating a wafer process.

[Explanation of symbols]

1,106: reticle, 2,107: reticle stage, 3,109: reduction projection lens, 4,110: surface position detection light projecting system, 5,114: surface position detection light receiving system, 6,11
2: wafer, 7, 113: reference plane mirror, 7a: focus detection mark, 8, 111: xyz stage, 1
1, 15, 27, 81, 84, 123: mirror, 12,
82, 124: objective lens, 13, 141: beam splitter, 14, 83: relay lens, 16: roof prism, 17, 85: elector, 18, 86, 126: position sensor, 21, 140: fiber, 22: lens, 2
5: fiber, 26: condenser lens, 28: reticle reference mark, 28a: reticle alignment mark on reticle reference mark, 29a: reticle alignment mark on reticle, 41: observation microscope, 51, 133: stage drive system, 52 , 148: objective lens driving system, 53,
55: relay lens driving system, 54: observation microscope driving system,
61: surface position detection system, 62: TTL focus detection system,
71: autofocus control system, RW: focus detection mark, 108: window cutout, 127: detection optical system, 1
31: autofocus detection system, 132: autofocus control system, 146: controller, 147: image signal analyzer.

Claims (18)

[Claims] 1. An apparatus for projecting and exposing a pattern on a first substrate onto a second substrate via a projection optical system, wherein the first substrate and the second substrate are exposed via the projection optical system. A detection optical system for detecting a position, comprising a detection optical system for detecting the position of the first substrate in the optical axis direction of the projection optical system, based on the detection results of both substrates, the first substrate A means for controlling a focus position at the time of projecting and exposing on the second substrate. 2. In a detection optical system for detecting a position of the first substrate, an image on a position detection sensor in the optical system is formed by sequentially moving a lens in the detection optical system in an optical axis direction. The projection exposure apparatus according to claim 1, wherein the state is changed. 3. A detection optical system for detecting a position of the second substrate, wherein the position of the second substrate in the direction of the optical axis of the projection optical system is sequentially moved, thereby obtaining a position in the detection optical system. 3. The projection exposure apparatus according to claim 1, wherein an image formation state on a detection sensor is changed. 4. A detection optical system for detecting a position of the first substrate and a detection optical system for detecting a position of the second substrate, at least a part of the same optical system, and On one substrate and on the second substrate, there is a dedicated mark for focus detection, and a detection optical system that detects the position of the second substrate via the first substrate and the projection optical system. The projection exposure apparatus according to any one of claims 1 to 3, wherein both marks form an image on a position detection sensor in the inside. 5. A detection optical system for detecting the positions of the first substrate and the second substrate performs position measurement in the optical axis direction of the projection optical system and also performs position measurement in a direction orthogonal to the optical axis. The projection exposure apparatus according to claim 1, wherein: 6. A position of the projection optical system in an optical axis direction is detected using an alignment mark in a peripheral region on the first substrate, and the position of the projection optical system is detected through a windowed portion on the first substrate. The projection exposure apparatus according to claim 1, wherein a focus-only mark on the second substrate is measured. 7. At least a part of an optical system for detecting a position of the first substrate is an alignment optical system for aligning a reference mark held on an apparatus with the first substrate. 7. The projection exposure apparatus according to claim 6, wherein the optical system for detecting the position of the second substrate has another optical system separately therefrom. 8. A method of projecting and exposing a pattern on a first substrate onto a second substrate via a projection optical system, wherein a position of the first substrate in an optical axis direction of the projection optical system is detected. A first step of detecting by a system, a second step of detecting the position of the second substrate by the detection optical system via the first substrate and the projection optical system, based on the detection results of both substrates And a third step of controlling a focus position when projecting and exposing the first substrate onto the second substrate. 9. The method according to claim 1, wherein, after the focus measurement on the pattern on the first substrate by the detection optical system,
9. The projection exposure method according to claim 8, wherein a focus of a position sensor in the detection optical system is focused on a pattern on the first substrate. 10. Immediately after the first substrate has been replaced,
The pattern on the first substrate is projected and exposed on the second substrate by performing a procedure of the first step, the second step, and the third step. Projection exposure method. 11. A projection exposure is performed on the second substrate without performing the first step or the first and second steps depending on a predetermined time or the number of the second substrates. The projection exposure method according to claim 10, wherein the control of the focus position is performed based on a focus position with respect to the second substrate immediately before. 12. A step of installing a group of manufacturing apparatuses for various processes including the exposure apparatus according to claim 1 in a semiconductor manufacturing plant, and a step of manufacturing a semiconductor device by a plurality of processes using the group of manufacturing apparatuses. A device manufacturing method comprising: 13. A method for connecting said group of manufacturing apparatuses via a local area network, and performing data communication between said local area network and an external network outside said semiconductor manufacturing factory, the information relating to at least one of said group of manufacturing apparatuses. 13. The method of claim 12, further comprising the step of: 14. A semiconductor manufacturing plant different from the semiconductor manufacturing plant by accessing a database provided by a vendor or a user of the exposure apparatus via the external network to obtain maintenance information of the manufacturing device by data communication. 13. The method according to claim 12, wherein data is communicated with the device via the external network to control production. 15. A manufacturing apparatus group for various processes including the exposure apparatus according to claim 1, a local area network connecting the manufacturing apparatus group, and an external network outside the factory can be accessed from the local area network. A semiconductor manufacturing factory having a gateway for performing data communication of information on at least one of the manufacturing apparatus groups. 16. The semiconductor device according to claim 1, which is installed in a semiconductor manufacturing plant.
7. The maintenance method of an exposure apparatus according to any one of claims 7 to 7, wherein a vendor or a user of the exposure apparatus provides a maintenance database connected to an external network of the semiconductor manufacturing plant; A step of permitting access to the maintenance database via the external device, and a step of transmitting maintenance information stored in the maintenance database to the semiconductor manufacturing plant via the external network. Method. 17. The exposure apparatus according to claim 1, wherein a display, a network interface,
An exposure apparatus, further comprising: a computer that executes network software, and capable of performing data communication of maintenance information of the exposure apparatus via a computer network. 18. The network software,
Provided on the display is a user interface for accessing a maintenance database provided by a vendor or a user of the exposure apparatus connected to an external network of a factory where the exposure apparatus is installed, and from the database via the external network. 18. The device according to claim 17, which makes it possible to obtain information.