JPH0521320A - X-ray aligner - Google Patents

Abstract

PURPOSE:To provide an X-ray aligner using synchrotron radiation which can irradiate with X-ray of a required amount to an exposure region on a photosensitive substrate almost uniformly. CONSTITUTION:An oscillation X-ray beam 34 from a beam line 22 is cast to an exposure region of a photosensitive substrate 21 which is held to a movable substrate stage 24 through an irradiation region setting device 19 and a mask 20. The irradiation region setting device 19 is provided with a second X-ray sensor 31 and the substrate stage 24 is provided with a first X-ray sensor 33. Output of both the sensors is compared and measured before actual exposure. An X-ray amount of an exposure region is measured based on output of the second X-ray sensor 31 during actual exposure. A first X-ray sensor 33 and the irradiation region setting device 19 contribute to accurate measurement of X-ray intensity distribution inside an exposure region.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray exposure apparatus which performs exposure using X-rays extracted from synchrotron radiation.

[0002]

2. Description of the Related Art As an exposure technique for transferring a quarter micron fine pattern, a system using soft X-rays contained in synchrotron radiation has been considered.

A so-called X-ray exposure apparatus adopting this method is usually constructed as shown in FIG. That is, reference numeral 1 in the figure indicates a storage ring. This storage ring 1 is equipped with an ultra-high vacuum doughnut-shaped container evacuated to about 10 ^-9 Torr, and a high-energy electron beam travels in this container in a constant orbit. When the electrons travel in this way, when the orbit of the electrons is bent by a magnetic field or the like, radiated light is emitted in the tangential direction.
This radiated light has a continuous spectrum from infrared to soft X-rays, and is generally called synchrotron radiation. In this X-ray exposure apparatus, the synchrotron radiation 2 is extracted via a beam line (not shown) connected to the storage ring 1. Then, the extracted synchrotron radiation 2 is applied to the mask 4 through the reflection mirror 3 for expanding the irradiation area, and the pattern on the mask 4 is applied to the photosensitive substrate 5 such as a resist-coated wafer or the like, for example. It is transferred to a size of 1: 1. Note that reference numeral 6 in the drawing denotes a window member for separating the high vacuum region and the atmospheric region.

The synchrotron radiation 2 is a parallel light beam, and its divergence angle is about 1 mrad. Therefore, the width in the orbital plane direction (horizontal direction) is 1 even at a distance of 10 m from the light source.
It is about 0 mm. That is, synchrotron radiation 2
Is equivalently considered to be light from a linear light source. Therefore, for example, in order to uniformly transfer to a 25 mm square area on the wafer, it is necessary to vertically move the wafer during irradiation so as to expand the irradiation area in the vertical direction. Therefore, in general, the reflection mirror 3 is provided, and by swinging the reflection mirror 3, the irradiation range in the vertical direction is expanded. Further, the synchrotron radiation 2 includes a wide range of wavelengths, as indicated by f ₁ in FIG. But,
Considering the maximum range of photoelectrons in the resist and the Frinel diffraction effect in the mask 4, 7 to 12 can be used for exposure.
It is an angstrom X-ray. It is necessary to provide an appropriate filter in order to set in this proper wavelength range. Therefore, in general, the reflection mirror 3 is formed of, for example, Pt coating so as to also serve as a filter on the short wavelength side as indicated by f ₂ in FIG. 19, and the window member 6 is formed of Be or the like. As indicated by f ₃ in FIG. 19, the long wavelength side filter is also used to extract only the X-rays in the proper wavelength range (hatching area). In addition, in this type of exposure apparatus, in order to accurately transfer the fine pattern on the mask 4 onto the wafer, X is irradiated onto the wafer.
The dose must be precisely controlled according to the sensitivity of the photosensitive material applied to the wafer. For that purpose, it is necessary to precisely control the irradiation time so that the integrated value of the X-ray dose irradiated onto the wafer through the mask 4 becomes constant. But,
Since it is not possible to directly detect the X-ray dose irradiated on the wafer during actual exposure, it is necessary to detect it by some indirect means. The intensity of the synchrotron radiation 2 is determined by the beam energy in the storage ring 1, the radius of curvature of the orbit and the number of electrons. The life of the electron beam in the storage ring 1 depends on the existence of residual gas,
That is, it depends on the degree of vacuum in the storage ring 1. Therefore, the intensity of the synchrotron radiation 2 radiated from the storage ring 1 decreases with time as shown in FIG. When this decrease becomes large, it is necessary to re-inject the electrons into the storage ring 1 using an injection accelerator such as a synchrotron, a linac, or a microtron. In this way, the intensity of the synchrotron radiation 2 is constantly changing. Therefore, in general, Japanese Patent Application No. 64-353
As shown in No. 00, the fact that the magnitude of the electron beam current in the storage ring 1 and the intensity of the synchrotron radiation are in a proportional relationship is used to make the integrated value of the electron beam current constant. The irradiation time is controlled.

However, the X-ray exposure apparatus adopting the above method has the following problems. That is, in the method of managing the irradiation time so that the integrated value of the electron beam current in the storage ring 1 is constant, some elements existing in the path from the storage ring 1 to the wafer surface are aged. When a characteristic change accompanying the change occurs, it cannot be promptly dealt with. Further, the reflection mirror 3 for enlarging the irradiation area has a difference in reflectance depending on the incident angle θ, as shown in FIG. Therefore, as shown in FIG. 22, there is a difference in the irradiation X-ray dose between the start end and the end end of the irradiation region enlarged by the reflection mirror 3. Such a difference is not desirable. However, it is difficult for the conventional device to eliminate the above-mentioned difference. Further, the horizontal intensity distribution of the synchrotron radiation 2 emitted from the storage ring 1 is not necessarily uniform, and may have a non-uniform intensity distribution as shown in FIG. 23, for example. With such an intensity distribution, the distribution of the irradiation X-ray dose on the wafer surface becomes non-uniform, and the degree of the non-uniformity is further emphasized by the difference in the reflectance of the reflection mirror 3. Therefore, it is desired to eliminate such nonuniformity, but it is difficult to eliminate the above nonuniformity in the conventional device.

[0006]

As described above, in the conventional X-ray exposure apparatus using synchrotron radiation, it is theoretically difficult to irradiate the photosensitive substrate with a certain amount of X-rays. However, it was difficult to uniformly irradiate the exposed area on the photosensitive substrate with X-rays. Therefore, an object of the present invention is to provide an X-ray exposure apparatus that can solve the above-mentioned problems.

[0007]

To achieve the above object, according to one embodiment of the present invention, a storage ring and
A means for extracting the synchrotron radiation from the storage ring, a means for extracting the X-ray component in the synchrotron radiation extracted by this means, and a photosensitive substrate to be irradiated with the X-rays extracted by this means are supported. A movable substrate stage, a mask stage arranged in front of the substrate stage to hold an exposure mask, and a swingable or movably arranged path extending from the storage ring to the mask stage. In an X-ray exposure apparatus including a reflection mirror that enlarges an X-ray irradiation area, a first X-ray sensor provided on the substrate stage and the X-ray of the X-ray between the storage ring and the mask stage. A second X, which is provided so that a part of it can be detected, and which is used to simulate the output of the first X-ray sensor during actual exposure.
And a line sensor.

[0008]

Before performing actual exposure, the substrate stage is moved to a position where the first X-ray sensor receives X-ray irradiation. In this state, X-ray irradiation is actually performed, and the first X
The output of the line sensor and the output of the second X-ray sensor are compared. The second X-ray sensor detects part of the X-ray emitted from the storage ring. Therefore, the first X
The output of the line sensor and the output of the second X-ray sensor are in perfect proportion. Therefore, at the time of actual exposure, the irradiation X-ray dose of the actual exposure area can be known from the output of the second X-ray sensor, and eventually, it is possible to irradiate the photosensitive substrate with a desired fixed amount of X-rays. Become. In this case, even if the characteristics of various elements that exist in the path from the storage ring to the mask stage change due to aging, etc., this characteristic change can be quickly responded to, and precise control of the irradiation X-ray dose is possible. Becomes

Since the first X-ray sensor is provided on the substrate stage, the X-ray intensity distribution in the actual exposure area can be obtained. Therefore, it becomes possible to set the irradiation conditions so as to make the intensity distribution uniform.

[0010]

Embodiments will be described below with reference to the drawings. FIG. 1 conceptually shows an X-ray exposure apparatus according to an embodiment of the present invention.

Reference numeral 10 in the figure shows a storage ring for traveling a high-energy electron beam in a constant orbit. A beam line (not shown) is connected to the storage ring 10, and the synchrotron radiation 11 is extracted via this beam line. Then, the extracted synchrotron radiation 11 has a first intensity distribution correction device 12 and a correction path 14 of a second intensity distribution correction device 13,
Through the shutter device 15, it is guided to a reflection mirror 17 for enlarging the irradiation area, which is oscillated by a constant period and a constant amplitude as shown by a solid arrow 16 in the figure. The synchrotron radiation 11 reflected by the reflection mirror 17 passes through the end of the beam line, that is, the window member 18 that separates the ultrahigh vacuum atmosphere and the atmospheric atmosphere, and then finally determines the irradiation area. The mask 20 is irradiated through the window of 19.
Then, the pattern on the mask 20 is transferred onto a photosensitive substrate 21 such as a resist-coated wafer.

Also in this apparatus, the reflecting mirror 17 is formed of, for example, platinum coating so as to serve also as a filter on the short wavelength side. Similarly, the window member 18 is made of Be so as to also serve as a filter on the long wavelength side. Due to these filter functions, the photosensitive substrate 21 has an appropriate wavelength range.
X-rays of ~ 12 Å are irradiated.

The first intensity distribution correction device 12 and the second intensity distribution correction device 13 correct the intensity distribution based on previously obtained data, and the configuration and the correction method will be described later.

The mask 20 is held by a mask stage, and the photosensitive substrate 21 is supported by a movable substrate stage. The mask stage, the substrate stage, and the irradiation area setting device 19 arranged in the atmosphere are configured as shown in FIG.

In the figure, reference numeral 22 denotes a beam line, and the above-mentioned Be window member 18 is attached to the end of the beam line 22. And the beam line 22
The irradiation area setting device 19, the mask stage 23, and the substrate stage 24 are arranged in this order from the window material 18 side on the extension line of the axis line. The irradiation area setting device 19
It is arranged as close to the mask stage 23 as possible.

With reference to the Cartesian coordinates shown in the figure, the irradiation area setting device 19 has two light shield plates 25a and 25b arranged movably in the x direction on the xy plane, and xy so as to overlap them. It is provided with two light shield plates 26a and 26b arranged on a plane so as to be movable in the y direction. The light shielding plates 25a and 25b are independent of the actuator 27.
a, 27b, and these actuators 2
The position in the x direction is freely set by 7a and 27b. Similarly, the light shielding plates 26a and 26b are independently connected to the actuators 28a and 28b, respectively, and the positions in the y direction can be freely set by these actuators 28a and 28b. In addition, each of the light shielding plates 25a, 25
b, 26a, and 26b are positioned based on a reference position that is obtained in advance. As a result, the size of the window 29 that determines the final irradiation area, that is, the exposure area, and its position on the xy axes are determined.

In this embodiment, as shown in FIG. 3, an amorphous silicon semiconductor or an avalanche photodiode is formed on the surface of the light shielding plates 25a and 26a on the window material 18 side along the edge of the window 29. X-ray sensors 31 and 32 (second X-ray sensor) having a width of several 100 μm formed by (APD) or the like are attached.

A mask stage 23 for holding the mask 20.
Further, the substrate stage 24 supporting the photosensitive substrate 21 having the surface coated with the photosensitive material is usually shown with a total of 6 axes in the x-axis, y-axis and z-axis (z ₁ , z ₂ , z ₃ including tilt) directions. Not equipped with a precision movement mechanism. Then, the mask 20 and the photosensitive substrate 2 are aligned by an alignment method that optically aligns them.
The relative position with respect to 1 and the gap are set. In this embodiment, an X-ray sensor 33 (first with a diameter of several 100 μm formed by an amorphous silicon semiconductor, an avalanche photodiode (APD), or the like is formed on the surface of the substrate stage 24 on the mask stage 23 side. 1
X-ray sensor) is attached.

Here, an irradiation area setting device 19 capable of freely setting the size of the window 29 for determining the irradiation area and its position on the xy axes is provided, and X-rays are provided along the edge of the window 29. The meaning of providing the sensors 31 and 32 and providing the X-ray sensor 33 on the movable substrate stage 24 will be described.

The irradiation area of the synchrotron radiation 11 emitted from the storage ring 10 is expanded by the swinging movement of the reflection mirror 17. Now, let us say that the hatched portion in FIG. 3 is the cross-sectional shape of the oscillating X-ray beam 34 actually taken out, and the area surrounded by the two-dot chain line 35 is the expanded irradiation area, and the window 29 It is assumed that the defined area is the exposure area 36 used for actual transfer. The X-ray sensor 33 is moved to the exposure area 36 by moving the substrate stage 24.
Located inside. When the irradiation region 35 is actually irradiated with X-rays in this state, the X-ray sensor 31 (32) and the X-ray sensor 3
3 and 3 simultaneously detect the oscillating X-ray beam 34. Therefore, the X-ray intensity of the actual exposure area 36 on the substrate stage 24 can be known by the output of the X-ray sensor 33, and X-ray intensity can be obtained based on the ratio of the output of the X-ray sensor 31 and the output of the X-ray sensor 33. From the output of the line sensor 31, the X of the actual exposure area 36 on the substrate stage 24 is also measured.
You can know the line strength. Since it is necessary to position the photosensitive substrate 21 in the exposure area 36 at the time of actual exposure, the intensity of the irradiated X-ray cannot be detected by the X-ray sensor 33, but this intensity can be detected by the X-ray sensor 31 (32). It can be detected accurately. Thus, the X-ray sensor 31 (32) is provided in order to know the X-ray intensity of the actual exposure area 36 on the photosensitive substrate 21 during the actual exposure.

On the other hand, the irradiation area setting device 19 can freely set the size of the window 29 that determines the exposure area 36 and its position on the xy axes. Therefore, as shown in FIG. 4, the size of the window 29 is made sufficiently small, X-rays are irradiated in this state, and the position of the window 29 is set to x within the exposure region 36.
If the X-ray sensor 33 is moved in the y direction and the substrate stage 24 is controlled to position the X-ray sensor 33 behind the window 29 and the X-ray intensity at each position is measured, the distribution of the X-ray intensity in the exposure area 36 can be obtained. It becomes possible to investigate. In this way, the exposure area 36
An irradiation area setting device 19 is provided to realize the setting and the X-ray intensity distribution measurement in the exposure area 36. Then, the obtained X-ray intensity distribution data in the exposure area 36 is used for the first intensity distribution correction device 13 and the second intensity distribution correction device 13 described below.
It is used as a material for determining the correction amount in the intensity distribution correction device 14.

The first intensity distribution compensator 12 includes a synchrotron radiation 11 emitted from the storage ring 10.
Is for correcting the intensity distribution in the horizontal direction, that is, the direction along the track surface of the storage ring 10, and is configured as shown in FIG. 5, for example. This figure shows an example in which an X-ray beam having an intensity distribution characteristic in which the X-ray intensity at the center in the horizontal direction is higher than that at both ends is corrected to a substantially flat intensity distribution. The oscillating X-ray beam 34 having such intensity distribution characteristics is shown in FIG.
As shown in FIG. 6, when the area is expanded by the reflection mirror 17 and the irradiation area 35 is irradiated, the X-ray intensity distribution at each position in the exposure area 36 defined by the window 29 is shown in FIG.
As shown in (b). As described above, the horizontal intensity distribution of the oscillating X-beam 24 is higher in the central portion than in the both end portions, so that the tendency also appears in the exposure region 36, the central portion V ₂ is high, and both end portions V ₁ , V ₃ becomes lower. In the vertical intensity distribution, the influence of the incident angle on the reflection mirror 17 appears, and the C-line with the smallest incident angle is high and the A-line with the largest incident angle is low.

Such intensity distribution characteristics are not preferable. Therefore, the first intensity distribution correction device 12 has a function of flattening the intensity distribution in the horizontal direction. That is, as shown in FIG. 5, a beam shaping mechanism 37 that shapes the cross-sectional shape of the synchrotron radiation 11 emitted from the storage ring 10 is provided. The beam shaping mechanism 37 has a rectangular shaping window 38 similar to the original cross-sectional shape of the synchrotron radiation 11 emitted from the storage ring 10. The upper frame 39 in the figure forming the shaping window 38 has the characteristics shown in FIG.
In order to limit the light passing through the center of the shaping window 38, it has a protrusion 39a protruding downward in a mountain shape.

Since such a shaping window 38 is provided,
Light passing through both ends of the shaping window 38 is not restricted,
The light passing through the center is narrowed down by the protrusion 39a. That is, the amount of light in the central portion is reduced. Therefore, when the light passing through the beam shaping mechanism 37 is irradiated, the exposure area 36
The X-ray intensity of each part inside is shown in FIG. 7 corresponding to FIG.
become that way. As can be seen from this figure, the presence of the first intensity distribution correction device 12 improves the intensity distribution characteristic to be substantially flat in the horizontal direction.

However, as is clear from FIG. 7, there is a difference in the X-ray intensities on the A line, B line, and C line in the exposure area 36 only by the above correction, and good transfer cannot be expected. The above difference is caused by the difference in reflectance due to the difference in the angle of incidence on the reflection mirror 17. The second intensity distribution correction device 13 is responsible for making the difference zero.

As described above, the first intensity distribution correction device 12
From this, a shaped radiation light beam shaped into a cross-sectional shape 40 in FIG. 8 is emitted. Second intensity distribution correction device 13
Guides the shaped radiation beam 40 emitted from the first intensity distribution correction device 12 to the correction path 14. In this correction path 14, a light shield for further correcting the cross-sectional shape of the shaping radiation light beam 40 by adjoining to the side 41 forming the cross section of the shaping radiation light beam 40 and extending horizontally in a straight line. A plate 42 is provided so as to be movable in a direction indicated by a solid arrow 43 in the figure. The light shield plate 42 is reciprocally driven in the direction indicated by a solid arrow 43 by an eccentric cam or the like driven by a drive device 45 in synchronization with the swinging movement of the reflection mirror 17.

Explaining with reference to the exposure area 36 shown in FIG. 6A, the light shield plate 42 is driven as follows. That is, as shown in FIG. 8, the shaped radiation beam 40 is not blocked at the position of the A line where the incident angle to the reflecting mirror 17 is the largest, and the C line position where the incident angle to the reflecting mirror 17 is the smallest is shown in FIG. As shown in (a), the blocking width of the shaped radiation beam 40 is increased, and the reflection mirror 1
At the position of the B line where the incident angle on 7 is intermediate, as shown in FIG. 9B, the shaping radiation light beam 40 is driven to be blocked by about half of the blocking width shown in FIG. 9A. Therefore, the light blocking action of the light blocking plate 42 that operates in synchronization with the swinging movement of the reflection mirror 17 can prevent a change in the light amount caused by a change in the incident angle on the reflection mirror 17.

As described above, the first intensity distribution correction device 12
10, the X-ray intensity distribution of the exposure area 36 is almost equal on the A line, the B line, and the C line, and the intensity distribution in the horizontal direction is combined, as shown in FIG. Are almost equal.

On the other hand, the shutter device 15 is constructed as follows. That is, as shown in FIG. 8, the correction path 14 is movably arranged in front of or behind the light shield plate 42 with reference to the traveling direction of the shaped radiation beam 40, as indicated by a solid arrow 46 in the figure. That is, a shutter plate 47 that selectively blocks the optical path is provided. The shutter plate 47 is driven by the drive device 48.
When the irradiation start signal S ₁ is given, the driving device 48 causes the shutter plate 47 to be opened stepwise in synchronization with the swing of the reflection mirror 17, as shown in FIG. Then, a signal S ₂ indicating the X-ray irradiation amount of the exposure area 36 converted based on the output of the X-ray sensor 31 (32) is introduced, and the X-ray irradiation amount of the exposure area 36 reaches the required irradiation amount. The shutter plate 47 is closed stepwise in synchronization with the swing of the reflection mirror 17, and the shutter plate 47 is completely closed at the timing when the required irradiation amount is finally reached. With such a shutter control method, it is possible to control the irradiation X-ray dose with higher accuracy as compared with a control method in which the shutter plate 47 is suddenly fully opened or fully closed.

Thus, according to the present X-ray exposure apparatus, the X-ray sensor 33 is provided on the substrate stage 24, and the X sensor 31 (32) is provided at a position along the edge of the window 29 of the irradiation area setting device 19. Therefore, before performing the actual exposure, the substrate stage 24 is moved to position the X-ray sensor 33 within the exposure area 36, and in this state, the irradiation area 35 is actually irradiated with X-rays and the X-ray sensor 31 ( 32) and X-ray sensor 33
The oscillating X-ray beam 34 is detected at the same time, and the outputs of the two sensors are comparatively measured. At the time of actual exposure, the photosensitive substrate 2 is output based on the output of the X-ray sensor 31 (32).
It is possible to know the X-ray intensity of the exposure area 36 above 1. Therefore, not only when the intensity of the synchrotron radiation 11 from the storage ring 10 changes, but also when the characteristics of various elements existing in the path from the storage ring 10 to the mask stage 23 change due to aging or the like. Even if there is, it is possible to quickly respond to this change, and it is possible to precisely control the irradiation X-ray dose to the exposure region 36.

Further, as in the embodiment, the substrate stage 24
If the X-ray sensor 33 is provided on the upper side and the irradiation area setting device 19 that can freely set the size of the window 29 that determines the exposure area 36 and the position on the xy axis is provided, the inside of the exposure area 36 X-ray intensity distribution can be measured. Therefore, it is possible to perform adjustment or control using the obtained X-ray intensity distribution data so that the X-ray intensity distribution in the exposure area 36 becomes more uniform.

Further, as in the embodiment, the first intensity distribution correction device 12 which uses the above X-ray intensity distribution data and makes the X-ray intensity distribution in the exposure region 36 substantially uniform by shaping the cross-sectional shape of the beam. When the second intensity distribution correction device 13 is provided, adjustment and control are facilitated as compared with the case where the swing speed of the reflection mirror 17 which is a precision processed product is changed to make the X-ray intensity distribution uniform. Can be planned.

Further, when the shutter device 15 for performing the opening / closing control as in the embodiment is provided, the irradiation X-ray dose is accurately controlled while the reflection mirror 17 is always oscillated with a constant period and a minimum amplitude. be able to.

The present invention is not limited to the above embodiment. That is, in the above-described embodiment, the X-ray sensor 31 (32) is provided at a position along the edge of the window 29 of the irradiation area setting device 19, and the X-ray sensor 31 (32) is provided.
Although the X-ray intensity of the exposure region 36 is measured at the time of actual exposure using, the X-ray sensor 31 (32) may be provided at a position other than the above position. For example, as shown in FIG.
A frame-shaped sensor base 50 is arranged on the front surface of the window 29 of the irradiation area setting device 19, and a thin support member 51 is provided on the sensor base 50 so as to cross the frame portion.
The line sensor 31 may be supported. In this case, since the support material 51 in the central portion becomes a shadow, the mask used has no pattern in the central portion as shown in FIG.
It becomes a combination with the mask 20a having a transfer pattern in the lower two areas 52a and 52b.

With such a configuration, it is necessary to combine it with the mask 20a shown in FIG. 14, but since the X-ray sensor 31 is attached to the fixed member called the sensor base 50, wiring, setting and the like can be facilitated. There is.

FIG. 15 shows an example in which an X-ray sensor 31 for measuring the X-ray intensity of the exposure area 36 at the time of actual exposure is provided in the beam line. In this example, the transmitted light of the reflection mirror 17 is used. That is, synchrotron radiation 1
1 has an emission spectrum indicated by f ₁ in FIG. 19, but part 11a is not reflected by the reflection mirror 17 made of platinum coating, for example. Therefore, the radiation spectrum indicated by f ₂ is in front of the reflection mirror 17.
Then, the radiation spectrum that passes through the window member 18 formed of Be and is applied to the mask is as shown by f ₃ . In this way, the shape of the radiation spectrum with which the mask is irradiated is determined by the materials of the reflection mirror 17 and the window member 18, and therefore the X-ray dose with which the mask is irradiated and the transmission X-ray dose through the reflection mirror 17 are proportional. Therefore, in this example, the X-ray sensor 31 is arranged behind the reflection mirror 17, and the substrate stage 24 is previously arranged.
The relative relationship between the output of the upper X-ray sensor 33 and the output of the X-ray sensor 31 is obtained, and the irradiation X-ray dose of the exposure region 36 is measured from the output of the X-ray sensor 31 during actual exposure. The X-ray sensor 31 may be arranged in this way.

As described above, the X-ray exposure apparatus of the present invention is a combination of many devices such as a storage ring, a beam line, a mask stage, a substrate stage, first and second intensity distribution correction devices, and an irradiation area setting device. It is made up. Therefore, it may be difficult to align the center of each device with the center of the emitted light beam.

FIG. 16 shows a method for facilitating the fitting. That is, the irradiation area setting device 1 described above
9 is mounted on a table 60 capable of remote control of position control in the xy axis direction and the z axis direction. At the center of the table 60, a rectangular opening 61 is formed for passing the X-rays having the enlarged irradiation area. This opening 6
A positioning jig 62 having a rectangular cross section is selectively mounted on the spigot 1. Beam line 22 of alignment jig 62
The surface of the surface 63 located on the side is coated with fluorescent paint. A tapered hole is formed in the center of the surface 63 (center of the opening 61). A television camera 65 is installed on a frame 64 supporting the table 60 so that the surface 63 can be photographed.

In this method, the television camera 65 takes an image of fluorescence generated when the oscillating X-ray beam 34 is applied to the surface 63 of the positioning jig 62. In this case, irregular reflection occurs at the tapered hole portion, so that it is projected as a black dot. Therefore, the position of the table 60 is controlled so that the tapered hole is aligned with the center of the fluorescent light emitting region. By this control, the center of the irradiation area setting device 19 can be aligned with the center of the oscillating X-ray beam 34. In the matched state, as shown in FIG. 17, the side surface of each of the light shielding plates 25a, 25b, 26a, 26b is applied to the side surface of the positioning jig 62, and the position in this state is set to the light shielding plate 25a. , 25b, 26
The reference positions a and 26b are used. Therefore, after that,
The position of each of the light shielding plates 25a, 25b, 26a, 26b is controlled with reference to the reference position. After the alignment, the alignment jig 62 is removed through the removal port 66.

On the other hand, the substrate stage 24 side is aligned as follows. That is, the substrate stage 24
Are usually arranged on the vibration isolation table 67, and the whole of them are arranged in the constant temperature chamber 68. Then, the vibration isolation table 67
A pedestal 69 is arranged on the front surface of the substrate stage 24 above the mask stage 23.
An alignment optical system 70 for arranging the mask 20 and the photosensitive substrate 21 relative to each other is arranged.
The vibration isolation table 67 is configured so that its position can be adjusted in the height direction (y-axis direction). The pedestal 69 is supported by an air bearing so that its position can be adjusted in the x, y direction and the z-axis direction.

The irradiation area setting device 1 is provided at the center of the pedestal 69.
A rectangular opening 71 through which the oscillating X-ray beam 34 that has passed through 9 is formed, and a positioning jig 72 is selectively mounted in the spigot in this opening 71. The positioning jig 72 has the same configuration as the positioning jig 62 described above, that is, a surface 73 positioned on the irradiation area setting device 19 side.
Fluorescent paint is applied to the center of the surface 73 (opening 7
A tapered taper hole is formed at the center of 1). A television camera 74 is installed at the front position of the gantry 69 so that the surface 73 can be photographed. Also in this case, the oscillating X-ray beam 34 moves the surface 73 of the alignment jig 72.
The fluorescent light generated when it is illuminated by the television camera 7
4, and the positions of the vibration isolation table 67 and the pedestal 69 are controlled so that the tapered hole is aligned with the center of the fluorescence emission region.
By this control, the opening 7 is formed at the center of the oscillating X-ray beam 34.
The centers of 1 can be matched. Then, after the alignment is completed, the alignment jig 72 is removed. Note that reference numeral 75 in FIG. 16 denotes a laser interferometer for performing positioning. By adopting such a method, the center of each device can be easily aligned with the center of the emitted light beam.

Further, in the embodiment shown in FIG. 1, the first intensity distribution correction device 12 and the second intensity distribution correction device 13 are provided separately, but some elements are shared. Good. Further, although the reflecting mirror is swung in the above-described embodiment, the reflecting mirror having an arc reflecting surface may be reciprocated.

[0043]

EFFECTS OF THE INVENTION (1) The first X on the movable substrate stage.
A line sensor is provided and a second X sensor is provided between the storage ring and the mask stage so that a part of the X-rays can be detected. Therefore, the outputs of both sensors can be comparatively measured before actual exposure. Then, during the actual exposure, the X-ray intensity of the exposure area on the photosensitive substrate can be measured based on the output of the second X-ray sensor. Therefore, not only when the intensity of the synchrotron radiation from the storage ring changes, even when the characteristics of various elements existing in the path from the storage ring to the mask stage change due to aging, etc. This change can be dealt with promptly, and precise control of the irradiation X-ray dose to the exposure area becomes possible.

(2) Since the first X-ray sensor is provided on the movable substrate stage, and the irradiation area setting device that can freely set the size and position of the window that determines the exposure area is provided. The X-ray intensity distribution in the exposure area can be accurately measured. Therefore, it is possible to adjust or control the obtained X-ray intensity distribution data so that the X-ray intensity distribution in the exposure area becomes substantially uniform.

(3) Using the X-ray intensity distribution data, the first intensity distribution correcting device and the second intensity distribution correcting device for shaping the cross-sectional shape of the beam to make the X-ray intensity distribution in the exposure region substantially uniform. Since the apparatus is provided, adjustment and control can be facilitated as compared with the case where the swing speed of the reflection mirror, which is a precision processed product, is changed to make the X-ray intensity distribution uniform.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an X-ray exposure apparatus according to an embodiment of the present invention,

FIG. 2 is a schematic perspective view showing an irradiation area setting device, a mask stage and a substrate stage incorporated in the same device,

FIG. 3 is a diagram for explaining the functions of X-ray sensors provided in an irradiation area setting device and a substrate stage,

FIG. 4 is a diagram for explaining an example of measuring an X-ray intensity distribution in an exposure area by using an irradiation area setting device and an X-ray sensor provided on a substrate stage.

FIG. 5 is a structural explanatory view of a first intensity distribution correction device,

FIG. 6 is a view for explaining the operation of the first intensity distribution correction device,

FIG. 7 is a diagram for explaining the operation of the first intensity distribution correction device,

FIG. 8 is a configuration explanatory view of a second intensity distribution correction device and a shutter device,

FIG. 9 is an operation explanatory view of the second intensity distribution correction device,

FIG. 10 is a diagram for explaining an X-ray intensity distribution in an exposure area obtained by a combination of a first intensity distribution correction device and a second intensity distribution correction device;

FIG. 11 is an operation explanatory view of the shutter device,

FIG. 12 is a view for explaining a different installation example of the second X-ray sensor,

13 is a view seen in the direction of the arrow along line XX in FIG.

14 is a view for explaining an example of a pattern area of a mask when an X-ray sensor is provided at the position shown in FIG.

FIG. 15 is a view for explaining a further different installation example of the second X-ray sensor,

FIG. 16 is a diagram for explaining a method of optical axis alignment;

FIG. 17 is a diagram for explaining a procedure after optical axis alignment,

FIG. 18 is a conceptual diagram for explaining the basic configuration of an X-ray exposure apparatus that uses synchrotron radiation.

FIG. 19 is a spectrum diagram of synchrotron radiation and X-rays used for actual exposure;

FIG. 20 is a diagram showing an example of intensity change of synchrotron radiation with time;

FIG. 21 is a diagram showing a relationship between an incident angle on a reflection mirror and reflectance.

FIG. 22 is a diagram showing an X-ray intensity distribution in an exposure area,

FIG. 23 is a diagram showing an intensity distribution in a direction orthogonal to the swinging direction of a swinging X-ray beam.

[Explanation of symbols]

10 ... Storage ring, 11 ... Synchrotron radiation, 12 ... First intensity distribution correction device,
13 ... Second intensity distribution correction device, 14 ... Correction path, 15 ...
Shutter device, 17 ... Reflective mirror,
18 ... Window material, 19 ... Irradiation area setting device, 2
0 ... Mask, 21 ... Photosensitive substrate, 22 ... Beam line, 23 ... Mask stage, 24 ...
Substrate stage, 25a, 25b ... Light shielding plate,
26a, 26b ... Light shielding plate, 27a, 27b ... Actuator, 28a, 28b ... Actuator, 29 ...
Window, 31, 32 ... X-ray sensor (second), 33 ... X-ray sensor (first), 34 ... Oscillating X-ray beam, 35 ...
Irradiation area, 36 ... Exposure area, 37
... Beam shaping mechanism, 38 ... Shaping window, 40
Shaped radiation beam 42, light shielding plate, 44, 45 ... Drive device, 47 ... Shutter plate, 48 ... Drive device 62, 72 ... Jig for alignment, 65, 74 ... Television camera.

Claims (5)

[Claims] 1. A storage ring, means for taking out synchrotron radiation from the storage ring, means for taking out X-ray components in the synchrotron radiation taken out by this means, and X-rays taken out by this means. A movable substrate stage that supports the photosensitive substrate that is the target of beam irradiation, a mask stage that is placed in front of this substrate stage and holds an exposure mask, and a path from the storage ring to the mask stage. In an X-ray exposure apparatus provided with a reflecting mirror that is movably or movably arranged and expands an irradiation area of the X-ray beam,
A first X-ray sensor provided on the substrate stage and a part of the X-ray beam are provided between the storage ring and the mask stage so as to be able to detect a part of the X-ray beam. Second X used to simulate the output of
An X-ray exposure apparatus comprising a line sensor. 2. A storage ring, means for taking out synchrotron radiation from the storage ring, means for taking out X-ray components in the synchrotron radiation taken out by this means, and X-rays taken out by this means. A movable substrate stage that supports the photosensitive substrate that is the target of beam irradiation, a mask stage that is placed in front of this substrate stage and holds an exposure mask, and a path from the storage ring to the mask stage. In an X-ray exposure apparatus provided with a reflecting mirror that is movably or movably arranged and expands an irradiation area of the X-ray beam,
A first X-ray sensor provided on the substrate stage and a part of the X-ray beam are provided between the storage ring and the mask stage so as to be able to detect a part of the X-ray beam. Second X used to simulate the output of
An X-ray exposure apparatus comprising: a line sensor; and an irradiation area setting device that is provided on the front surface of the mask stage and that can freely set an irradiation area of the X-ray beam onto the photosensitive substrate. . 3. A storage ring, means for extracting synchrotron radiation from the storage ring, means for extracting X-ray components in the synchrotron radiation extracted by this means, and X-rays extracted by this means. A movable substrate stage that supports the photosensitive substrate irradiated with the beam, a mask stage that is arranged in front of the substrate stage and holds a mask for exposure, and swings in a range from the storage ring to the mask stage. An X-ray exposure apparatus comprising a reflection mirror which is movably or movably arranged and enlarges the X-ray irradiation area, and a first X-ray sensor provided on the substrate stage and the mask from the storage ring. A part of the X-ray beam can be detected up to the stage so that the first
Second X-ray sensor used to simulate the output of the X-ray sensor, and an irradiation area setting device provided on the front surface of the mask stage and capable of freely setting the irradiation area of the X-ray beam to the photosensitive substrate. And an intensity distribution correction provided on the path from the storage ring to the reflection mirror, for correcting the beam cross-sectional shape of the synchrotron radiation emitted from the storage ring and correcting the X-ray intensity distribution in the irradiation region. An X-ray exposure apparatus comprising: 4. The intensity distribution correction means includes a first correction means for correcting the intensity distribution in a direction orthogonal to the swinging or moving direction of the reflection mirror, and the reflection in synchronization with the movement of the reflection mirror. The X-ray exposure apparatus according to claim 3, further comprising a second correction unit that corrects an intensity distribution in a swinging direction or a moving direction of the mirror. 5. The second X-ray sensor according to claim 2, wherein the second X-ray sensor is fixed to a surface of the irradiation area setting device which receives the irradiation of the X-ray beam. X-ray exposure device.