JP3278892B2 - Exposure apparatus and method, and device manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus having an illumination device using a laser as a light source , an exposure method, and a device.
The present invention relates to a method of manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, semiconductor devices have been steadily miniaturized, and the minimum line width of a circuit pattern has been approaching from a submicron region to a quarter micron region.
For this reason, in reduction projection exposure apparatuses (such as steppers), a projection lens with a large numerical aperture has been developed.
In order to further advance the miniaturization of semiconductor devices, it is necessary to further shorten the wavelength of exposure light. Therefore, the g-line (435 mm) and i
Excimer lasers that can obtain light of a shorter wavelength instead of the line (365 mm) have begun to be used. Among them, especially K
rF and ArF excimer lasers are promising.

[0003]

In particular, KrF, ArF
The excimer laser light source is of a pulse oscillation type and emits a beam with high spatial coherence. This spatial coherence allows a fly-eye lens (optical integrator) for uniform illumination to be provided in the illumination optical system of the projection exposure apparatus. ) Occurs on the wafer as the photosensitive substrate. This interference pattern can be averaged by oscillating the illumination light during exposure for each pulse oscillation. In the future, if a highly sensitive resist is developed or the output of KrF or ArF excimer laser increases,
The number of pulses required for exposure will be reduced. Also, on the exposure apparatus side, the number of pulses required for erasing the interference pattern in order to increase the throughput tends to be reduced as much as possible. Therefore, it is necessary to manage the state of the spatial coherence of the excimer laser on the exposure apparatus side. That is, since the contrast of the interference pattern generated on the wafer depends on the degree of spatial coherence of the excimer laser, the minimum number of pulses required to expose one region on the wafer is predetermined. In addition, there arises a problem that the interference pattern is not reliably erased due to a change in spatial coherence.

[0004]

In <br/> present invention according to where claim 1 SUMMARY OF THE INVENTION, a laser light source (1) for emitting a beam having a predetermined spatial coherence, illumination target the beam
Of intensity distribution for irradiating with almost uniform intensity distribution
Means (2 to 5, 7, 9, 11, 15, 17, 21, 2
5, 27).
And the lighting system is capable of spatial coherence of the beam.
(CCD 30, image processing
System 31) and the detected value is within a predetermined range.
Adjust the optical conditions in the laser light source so that
Adjustment means (rear mirror 102, drive unit 107)
Illuminating the mask with the beam,
To transfer the pattern of the mask to multiple areas on the substrate.
Step and repeat method or step and scan
And exposing the substrate by a method.
You. Further, the present invention described in claim 9 provides a predetermined spatial code.
Laser light source for emitting beam with coherence (1)
When the beam is incident, the mask is almost uniform in intensity distribution
Illumination optical system (2-5, 7, 9, 11, 15,
17, 21, 25, 27) and the mask pattern
A substrate stage (WST) for holding a substrate to be transferred
In the exposure apparatus equipped with
The divergence angle of the beam
Detecting means (30, 31) for detecting a value corresponding to
Varying the optical conditions in the laser source to diverge its beam
Adjusting means (102, 107) for adjusting the angle and its substrate
Prior to the exposure operation to transfer the pattern to the
It is determined whether the set value is within a predetermined range.
In the case of, the adjustment means is activated and the divergence angle of the beam
And a correction control means (120) for correcting the
It is a sign. Further, the present invention according to claim 12 is provided.
Generates a pulse beam having a predetermined spatial coherence.
Emitted pulsed laser light source (1) and its pulse
An illumination system (2 to 5, 7, 9, 1, 1) for illuminating the mask with the beam
1, 15, 17, 21, 25, 27) and the mask
One area on the substrate where the pattern is to be transferred
Preset target pulse for exposure with beam
Control means for controlling the number of oscillations of the laser light source according to the number
An exposure apparatus having a step (105),
Part of the pulse beam from the light source is received and the pulse
Outputs signals according to changes in the spatial coherence of the beam
Detecting means (30, 31) for detecting
The degree of change in its spatial coherence based on the
Determining means (120) for determining
Target number of pulses set for exposure of that one area
Pulse number correcting means (120) for correcting
It is characterized by the following. The book according to claim 14
The invention provides an exposure apparatus according to any one of claims 1 to 13.
This is a device manufacturing method using a device. Further, claim 1
The present invention as described in 5, wherein the laser light source through the illumination optical system
These pulse beams are irradiated on the mask,
A method of exposing a substrate with the pulse beam through a mask
In accordance with the spatial coherence of the illumination beam
Value and, depending on the detected value, the laser
Adjusting the optical conditions in the light source and changing the number of exposure pulses on the substrate
Or at least one of
You.

[0005]

Here, the relationship between the spatial coherence and the beam divergence angle of the excimer laser will be described. KrF, A
rF excimer laser beam divergence angle θd (full angle bea
m divergence) is expressed as θd ≒ 3a / L (1). Here, a is the radius of the laser beam, and L is the length of the resonator.

According to a simple estimation, the coherence length Xc is expressed as Xc = λL / 2a (2) λ is the wavelength of the beam. (1),
From equation (2), Xc · θd ≒ (λL / 2a) (4a / L) = 2λ, which indicates that the coherence length can be obtained by knowing the divergence angle of the beam.

Therefore, in the present invention, a change in the divergence angle of the excimer laser beam is constantly monitored as a change in the spatial coherence on the exposure apparatus side or the like, and the spatial variation of the beam is changed according to the change in the divergence angle. He managed coherence.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an excimer stepper will be described with reference to FIG. The beam emitted from the excimer laser light source 1 is incident on an optical system 11 including a cylindrical lens via ultraviolet reflecting mirrors M ₁ , M ₂ , M ₃ , and M _4, and has a rectangular cross section LB _0. To a substantially square beam LB. The beam LB is bent in Murasakigaiyo reflection mirror M ₅ with the beam expander (or zoom lens) 1
5 and is enlarged to a predetermined cross-sectional dimension.

The parallel beam having a substantially square cross section emitted from the beam expander 15 enters the quartz prism 7 (polarizing means) and is separated into two types of polarized light. Subsequently, the two kinds of separated beams are incident on a quartz glass prism 9 for correction, and correct the traveling direction of the beams. Such a configuration is disclosed in detail in, for example, JP-A-3-16114.

After that, the two kinds of separated beams enter the scanning mirror 17 via the first-stage fly-eye lens 3 and the lens 4. The scanning mirror 17 includes a vibration source 19 such as a galvanometer, a piezo element, or a torsional vibrator.
And is swung at a controlled amplitude (deflection angle) and speed. Such a configuration is described in detail in, for example,
No. 1,598,737.

Next, the beam oscillated by the scanning mirror 17 is incident on the second fly-eye lens 5 through the lens 21, and is diverged after being condensed on its exit side as a number of tertiary light sources (spot lights). After being condensed by the condenser lens 25, the light is bent by the mirror 27 and enters the main condenser lens 2. Beams from each of a number of tertiary light sources are superimposed on the pattern area of the reticle R by the main condenser lens 2 to irradiate the circuit pattern area of the reticle R with a uniform intensity distribution. Then, the image of the circuit pattern area is projected and exposed on the wafer W by the projection lens PL.

In FIG. 1, in order to reduce the interference pattern, the beam emitted from the laser light source 1 is separated into two polarized beams having a predetermined angle by a polarizing means (quartz prism 7) to illuminate the reticle R. ing. Two interference patterns are generated which are shifted by the light and dark period of the interference pattern generated by each beam, and the two interference patterns cancel each other, resulting in a reduction in the contrast of the interference pattern.

Further, since the interference pattern generated on the wafer W also includes a periodic component corresponding to the distance between the element lenses of the fly-eye lens, the scanning mirror 17 is being exposed (a plurality of beam pulses). During the oscillation, the interference pattern is moved and averaged, and the contrast of the interference pattern is eliminated by the integration effect.

[0014] In the present embodiment here, a KrF excimer laser, or the purpose of examining the spatial coherence of the ArF excimer laser, a focusing lens L ₁ for monitoring the divergence angle of the laser beam of violet external reflecting mirror M ₅ placed behind, so as to focus the light leakage in the mirror M ₅ at the focal point of the lens L _1, and further established a CCD30 as a two-dimensional image sensor to the focal point. And CCD30
The divergence angle is measured by analyzing the image signal from the processing system 31. Light monitoring divergence angle may not be leaked light of the mirror M _5, it may be a light before entering the first fly's eye 3 after passing through the optical system 11 including a silicon lenses. For example, as shown in FIG. 2, guides the part of the light passing through the optical system 11 including a silicon lenses beam splitter (here low reflectance, high transmittance) branches to the condenser lens L _1, the Similarly to FIG. 1, the divergence angle may be measured by receiving light with the CCD 30.

FIG. 3 shows an overall configuration of a system for controlling the stepper having the configuration shown in FIG. 1 or FIG. In FIG.
In the laser light source 1, a laser tube 100 enclosing a gas serving as a laser medium and an electrode for oscillation trigger, a front mirror 101 having a predetermined reflectance (less than 100%) constituting a resonator, a rear mirror 102, wavelength selection A prism 103 for narrowing the band, a grating 104, and the like are provided as optical elements. Further, the laser light source 1 has an oscillation control unit 105 for applying a high voltage to the electrodes in the laser tube 100 to perform oscillation (trigger), and a grating 104 for always keeping the absolute wavelength of the oscillated laser beam constant. Adjustment drive unit 106 for adjusting the inclination of the mirror and the rear mirror 10
A drive unit 107 and the like for adjusting the inclination of 2 are provided. The drive unit 106 for wavelength adjustment includes the front mirror 1
In accordance with the beam wavelength detected by the wavelength detector (spectroscope) 110 that receives a part of the beam emitted from the light source 01, the angle of the grating 104 is adjusted so that the difference from a predetermined absolute wavelength falls within a standard. To change. Although the wavelength detector 110 is provided outside the main body of the laser light source 1 in FIG. 3, the wavelength detector 110 may be configured as a part of the main body of the laser light source 1.

The CCD 3 shown in FIG. 1 or FIG.
0, a signal corresponding to the beam divergence angle detected by the image processing system 31 (specifically, a value corresponding to the size of the beam spot formed on the CCD 30) is a driving unit 107 of the rear mirror 102 of the laser light source 1. And is also sent to the exposure control system 120. Drive unit 107
When the value of the beam divergence angle actually measured with respect to a predetermined value is out of an allowable range, the rear mirror 10
2 is changed.

The exposure control system 120 sends information such as the number of oscillation pulses, the emission intensity of each pulse, or the oscillation period to the oscillation control unit 105 of the laser light source 1 and the oscillation source 19 of the scanning mirror 17 shown in FIG. And outputs a drive command that is periodic to the pulse oscillation, and, if necessary, an illumination optical system (FIG. 1).
Outputs a command to adjust the extinction ratio of the dimming filter from the mirror M ₁ provided in the main condenser lens 2) in in (aperture diaphragm). Further, the exposure control system 120 inputs a value relating to the divergence angle from the image processing system 31, and
It also has a function of changing the value (Nmin) of the minimum number of pulses required for exposure of the above one shot area in accordance with a change in the beam divergence angle.

A main control device (master control system) 121 includes an exposure control system 120 and a stage control system 12 for controlling movement and positioning of wafer stage WST.
For example, a keyboard KB as an input device and a display unit (CRT, alarm, meter, etc.) 122 as an output device are connected. Wafer stage WST exposes a pattern image of reticle R to each of a plurality of shot areas on wafer W,
It moves in a step-and-repeat manner in the X and Y directions. The keyboard KB is used for various sequence settings and parameter settings, in addition to specifying in advance how many pulses are to be exposed per shot when exposing a certain wafer W. The main controller 121 prepares at least two modes in response to a change in the beam divergence angle at the time of exposure in accordance with designation from the keyboard KB, and switches between which mode is selected and which mode is used. It has. The two modes are a mode in which the divergence angle of the beam from the laser light source 1 is corrected by feedback control, and a mode in which the required minimum number of pulses N per shot according to a change in the divergence angle of the beam.
This is the mode for changing min.

The minimum pulse number Nmin affects the degree of smoothing when the scanning mirror 17 is swung during the exposure of one shot to move and smooth the interference pattern generated on the wafer W. That is, as the number of beam pulses oscillated while the scanning mirror 17 is swung by a certain angle increases, the amount of movement of the interference pattern per pulse becomes smaller and the smoothing effect is improved. . In the opposite case, the amount of movement of the interference pattern per pulse becomes rough, so that the smoothing effect is reduced. Therefore, the minimum value is set as the number of beam pulses per shot under the condition that the effect of smoothing the interference pattern is not reduced and the throughput is not reduced. Further, when the average contrast of the interference pattern is relatively large, the minimum pulse number Nmin tends to increase accordingly. That is,
When the divergence angle of the beam becomes relatively small as compared with the expected value, the spatial coherence also increases, and the average contrast of the interference pattern also increases, so that the minimum pulse number Nmin increases accordingly, that is, It is preferable to change the amount of movement of the interference pattern per pulse to be small.

The divergence angle detected by the two-dimensional CCD 30 and the image processing system 31 in this way corresponds to the spatial coherence of the beam at the time of detection, as described above. Exposure control system 120 has a spatial coherence value capable of erasing the interference pattern from main controller 121,
That is, the standard value of the divergence angle is set, and when the spatial coherence of the beam becomes higher than the set value, the exposure control system 120 detects an error and the drive unit 107 of the laser light source 1
Give feedback to. FIG. 4 shows a flowchart of the sequence. FIG. 4 shows a sequence example in which one wafer is exposed by the step-and-repeat method using only the mode in which the beam divergence angle itself is corrected by feedback control among the two modes described above.

When an exposure start command is issued in step 200 of FIG. 4, the divergence angle is measured before actually exposing the wafer to check the spatial coherence of the laser beam (step 201). If this is performed at the same time as the energy check (measurement of the average intensity of the beam pulse) performed before the wafer exposure in order to set an appropriate exposure amount, the spatial coherence can be checked without lowering the throughput. If the value of the spatial coherence (the value of the divergence angle) is within the range in which the interference pattern can be eliminated, the initial minimum pulse number Nmin set in the main controller 121 is set in the exposure control system 120 ( Step 204) to start exposure (Step 20)
5). If not, a command is issued to the laser light source 1 to execute recovery (adjustment), and the angle of the rear mirror 102 is adjusted on the laser light source 1 side (step 202). During this time, the stepper is in a standby state, but if a sequence is arranged to execute another operation, for example, wafer alignment, during the recovery operation, there is substantially no standby time. That is, FIG. 1 or FIG.
Place a shutter for beam blocking between the mirror M ₅ and the beam expander 15 shown in, when performing step 201 of FIG. 4 in a closed state the shutter simultaneously wafer alignment (mark detection) by starting the operation If
The recovery operation of Step 202 can be completed during the wafer alignment operation (several seconds to several tens of seconds).

Further, as shown in FIG.
Is completed, it is determined in step 203 whether or not exposure of one wafer has been completed.
, A series of operations until the beam divergence angle is checked again can be executed in parallel with the wafer alignment operation. If it is determined in the first step 201 that the beam divergence angle is within the allowable value, the process proceeds to step 204.
, The exposure of the wafer is started. Needless to say, before that, the wafer alignment operation is executed.

Next, main controller 121 proceeds to step 205.
To open the shutter and start exposure for one shot area on the wafer. At this time, the exposure control system 120 issues a setting command for the neutral density filter, a driving command to the vibration source 19,
And outputs an oscillation trigger command and the like to the oscillation control unit 105,
One shot exposure is performed with the minimum pulse number Nmin. This one
During exposure to a shot, the CCD 30 and the image processing system 3
1. The exposure control system 120 continues to detect a change in the beam divergence angle.
At 07, it is detected whether or not the beam divergence angle has deviated from the allowable value (initial setting value), that is, whether or not an error has occurred. If it is determined in step 207 that an error has occurred,
The stepper stops the wafer stage WST by stepping on the next shot area on the wafer. Then, the user closes the shutter and proceeds to steps 202, 203,
01 to return the divergence angle of the beam to within the tolerance. Thereafter, in step 204, the minimum pulse number Nmin is set for the next shot area, the shutter is opened, and the execution of steps 205, 206, and 207 is resumed.

After the exposure of one shot, if it is determined in step 207 that there is no error, it is determined in step 208 whether or not the exposure of all shots on one wafer has been completed. Step 205 for exposing the next shot area.
Repeat the operation from. At this time, if the return destination when the determination in step 208 is negative is made to step 204, the minimum pulse number Nmin can be delicately changed for each shot area. That is, in the case of the sequence of FIG. 4, the image processing system 31 sequentially detects a change in the beam divergence angle during the exposure of one shot area. If the standard coherence is sufficiently small), the minimum pulse number Nmin set in advance as a standard is slightly (5-10
%) The exposure time for one wafer can be shortened because it can be reset slightly.

In general, the spatial coherence of a beam emitted from this type of laser light source 1 changes depending on the state of the gas in the laser tube 100 and the state of the electrodes. It hardly changes. Therefore, step 207 in the sequence shown in FIG. 4 may be omitted, and step 201 or 202 may be performed only once immediately before the start of exposure on one wafer. In order to realize such a sequence, it is necessary to perform step 20 before exposing the wafer.
When the beam divergence angle is checked in step 1, the amount of allowance for the allowable value is quantitatively obtained. If there is no allowance, the angle of the rear mirror 102 is adjusted in step 202 for safety for safety. Is desirably corrected in a direction to increase.

On the other hand, the sequence shown in FIG. 5 shows a case in which the mode for correcting the beam divergence angle itself and the mode for changing the minimum pulse number Nmin are actively used. In FIG. 5, steps having the same functions as those in FIG. 4 have the same reference numerals (200 to 202, 204, 205 to 208).
Is attached. The difference from FIG. 4 is that when an error of the beam divergence angle is detected in step 207 after the exposure of one shot is completed, steps 209 and 210 are executed.

When the wafer is exposed by the step-and-repeat method (or the step-scan method), when it is detected in step 207 that the beam divergence angle exceeds an allowable value during exposure of a certain shot area, step 209 is performed. Is negative (No), so that step 210 is executed. As described above, as the beam divergence angle decreases, the contrast of the interference pattern generated on the wafer increases, so the initially set minimum pulse number Nmin
Is set in the direction of increasing (raising). Minimum pulse number N
The extent to which min is increased can be determined by previously obtaining the correlation between the change from the allowable value of the beam divergence angle and the contrast of the interference pattern through experiments or the like. Also, as described above, since the spatial coherence of the beam does not fluctuate rapidly in a short time, step 210
The increase amount of Nmin in the above is set to a constant value which is expected based on the time required to expose all of the shot areas (or all of the remaining shot areas) of the wafer and the rate of change of the beam divergence angle. good. In this way, when the error of the beam divergence angle occurs during the exposure of one wafer, Nmi
The reset operation of n (step 210) can be performed only once.

If it is determined in step 209 that the exposure of one wafer has been completed, even if the next wafer exposure is to be executed as it is, an error has been detected in the previous step 207. The correct operation of erasing is not guaranteed. Therefore, step 209
After one wafer exposure is completed, the shutter is closed and the recovery operation of step 202 is immediately executed to correct the beam divergence angle itself.

As described above, according to the sequence of FIG.
During the exposure of at least one wafer, the contrast of the interference pattern is effectively homogenized only by changing the minimum pulse number Nmin, so that the step-and-repeat operation does not have to wait for the recovery of the laser light source 1; This is advantageous in terms of throughput as compared with the above sequence. When the throughput is considered more faithfully, the time required for exposing all the remaining shots on one wafer is increased by increasing the minimum pulse number Nmin from the initial value, and Compare the time of the recovery operation (including the opening and closing operation of the shutter) with the time of the recovery operation, and if the time of the recovery operation is shorter,
The recovery operation may be executed before starting the next shot exposure as in the sequence of (1). In this case, immediately before step 210, there is provided a step of comparing the time that increases when Nmin is raised with the time of the recovery operation, and further according to the comparison result, step 210 is performed.
And then go to step 205 or execute the recovery operation and then go to step 205.

The operation of the apparatus according to the present embodiment has been described above. If the spatial coherence of the beam is too low, the beam divergence angle increases and the beam transmission path (in the illumination optical system or in the laser light source 1) is increased. In some cases, the light amount loss in the transmission section from the exposure apparatus to the exposure apparatus becomes large. Therefore, when the value of the beam divergence angle sequentially detected by the image processing system 31 becomes extremely large, this fact is indicated on the display unit 12.
The error may be displayed as 2 or the like. Of course, even when the beam divergence angle becomes extremely large, if the divergence angle can be corrected to be smaller by adjusting the rear mirror 102 in the laser light source 1, a recovery operation may be performed as in step 202.

In this embodiment, the beam divergence angle (spatial coherence) in both the short side direction and the long side direction of the laser beam cross section is measured at a time by using the two-dimensional CCD 30 and the image processing system 31. However, in an illumination device using a normal excimer laser, the spatial coherence in the short side direction of the laser beam cross section becomes high, so that a two-dimensional CCD is used.
A one-dimensional line sensor may be used instead of 30 to measure only the short side direction of the laser beam cross section. Furthermore, a beam splitter for 2 divides the laser beam in the middle of the condenser lens L ₁ and the sensor is provided, by placing a one-dimensional line sensor in each of the two divided light paths, the long and the short side direction of the laser beam cross section It is also conceivable to separately measure the beam divergence angle with respect to the side direction. Further, the present embodiment has described the illumination device using the excimer laser,
Naturally, the invention is not limited to excimer lasers, but also other lasers with high spatial coherence, such as copper vapor lasers, Y
It is also effective for a lighting device using an AG laser.

In the embodiment of the present invention, the spatial coherence (divergence angle) of the beam is changed by minutely changing the inclination of the rear mirror 102 in the laser light source 1. May be finely moved, or the arrangement of the optical element capable of changing the beam divergence angle may be finely moved.

[0033]

As described above, according to the present invention, the state of the spatial coherence of the illumination beam is constantly controlled, so that the number of pulses required to reduce the interference pattern can be reduced. Even if a highly sensitive resist is used or the laser power is increased, exposure can be performed without lowering the throughput, which is very useful.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing a modification of the apparatus shown in FIG.

FIG. 3 is a block diagram showing a configuration of a control system of the apparatus shown in FIG.

FIG. 4 is a flowchart illustrating a first operation sequence of the apparatus shown in FIG. 1;

FIG. 5 is a flowchart illustrating a second operation sequence of the device shown in FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser light source 3, 5 fly-eye lens 30 CCD 31 image processing system 100 laser tube 101 front mirror 102 rear mirror 107 driver R reticle PL projection lens W wafer

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁷ Identification code FI H01L 21/30 527

Claims (15)

(57) [Claims] 1. An exposure apparatus comprising: a laser light source that emits a beam having a predetermined spatial coherence; and an illumination apparatus including an intensity distribution uniforming unit that irradiates the beam with an almost uniform intensity distribution to an illumination target. An apparatus, wherein the illuminating device includes a detecting unit configured to detect a value corresponding to a spatial coherence of the beam, and the laser light source so that the detected value is set within a predetermined range. Adjusting means for adjusting the optical conditions of the mask, while illuminating the mask with the beam,
Step to transfer the pattern to multiple areas on the substrate
Pull-and-repeat method or step-and-scan method
An exposure apparatus for exposing the substrate by using 2. The exposure apparatus according to claim 1, wherein the adjustment unit includes an angle adjustment member that adjusts the optical condition by changing an angle of a rear mirror that forms the laser light source. 3. A feedback control system for automatically correcting an optical condition in the laser light source by feedback control according to a deviation between a value detected by the detection means and a preset target value. The exposure apparatus according to claim 1, further comprising: 4. A prohibition unit for prohibiting a beam from the laser light source from reaching the illumination target when the value detected by the detection unit is out of a predetermined range, and the prohibition state is set. The exposure apparatus according to any one of claims 1 to 3, further comprising a display unit for displaying the fact. 5. The exposure apparatus according to claim 1, wherein the detection unit detects a value corresponding to spatial coherence in at least a short side direction in the beam cross section. 6. The exposure apparatus according to claim 1, wherein the detection unit includes a photodetector that receives the beam and outputs information according to a divergence angle of the beam. <br/> Device. 7. An exposure apparatus, wherein the laser light source emits a pulse beam, controls the laser light source so that the pattern is transferred to each of the regions, and changes the number of exposure pulses based on the detected value. according to any one of claims 1 to 6, further comprising a control means
Of the exposure apparatus. 8. When the value detected by the detection means is out of a predetermined range, at least one of the adjustment of the optical condition by the adjustment means and the change of the number of exposure pulses by the exposure control means. 8. The exposure apparatus according to claim 7 , further comprising control means for performing one of the operations. 9. A laser light source for emitting a beam having a predetermined spatial coherence, an illumination optical system for illuminating the mask with a substantially uniform intensity distribution by entering the beam, and a pattern of the mask is transferred. An exposure apparatus comprising: a substrate stage for holding a substrate; a detecting unit configured to receive at least a part of a beam incident on the illumination optical system and detect a value corresponding to a divergence angle of the beam; and the laser light source. Adjusting means for adjusting the divergence angle of the beam by changing the optical conditions within, and prior to an exposure operation of transferring the pattern to the substrate,
And determining whether or not the detected value is within a predetermined range, and when the detected value is outside the range, operating the adjusting unit to correct the divergence angle of the beam. Exposure equipment. 10. The substrate stage may be configured to transfer the pattern to a plurality of regions on the substrate.
The correction control unit monitors a value detected by the detection unit when exposure is performed on one region on the substrate, and based on the monitoring result, a next region 10. The exposure apparatus according to claim 9 , wherein the adjusting unit is operated before the exposure of the exposure is started. 11. The illumination optical system includes an optical integrator for equalizing the intensity distribution, the detection unit includes: a beam splitter that splits the pulse beam before entering the optical integrator; A lens system for condensing a part of the divided beams at a predetermined position, and a photoelectric detector for measuring a change in a cross-sectional dimension of the condensed beam.
The exposure apparatus according to 9 or 10 . 12. A pulsed laser light source for emitting a pulse beam having a predetermined spatial coherence, an illumination system for illuminating a mask with the pulse beam, and one region on a substrate on which a pattern of the mask is to be transferred. Control means for controlling the number of oscillations of the laser light source according to a preset target number of pulses, in order to expose a plurality of pulse beams, a part of the pulse beam from the laser light source Receiving
Detecting means for outputting a signal corresponding to a change in spatial coherence of the pulse beam; determining means for determining a degree of change in the spatial coherence based on a signal from the detecting means; and An exposure apparatus comprising: a pulse number correcting unit configured to correct a target pulse number set for exposure of the one area. 13. The exposure apparatus according to claim 12 , wherein the pulse number correction unit corrects the target pulse number to be increased when the spatial coherence is higher than a predetermined value. apparatus. 14. The device manufacturing method using the exposure apparatus according to any one of claims 1 to 13. 15. A method of irradiating a mask with a pulse beam from a laser light source through an illumination optical system, and exposing a substrate with the pulse beam through the mask, wherein a value corresponding to a spatial coherence of the illumination beam is determined. An exposure method, comprising: detecting and adjusting at least one of an optical condition in the laser light source and a change in the number of exposure pulses of the substrate according to the detection value.