JP3201025B2 - Exposure method and apparatus, and element 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 used for exposing a reticle pattern onto a photosensitive substrate when, for example, a semiconductor device or a liquid crystal display device is manufactured by a photolithography process. The present invention relates to an exposure apparatus including a control mechanism for setting an exposure amount on a substrate to an appropriate exposure amount.

[0002]

2. Description of the Related Art When manufacturing a circuit pattern of a semiconductor element or a liquid crystal display element by a photolithography process, an exposure apparatus (hereinafter referred to as a "reticle") for exposing a pattern of a photomask or a reticle onto a photosensitive substrate. For example, a stepper is used. The photosensitive substrate
A photosensitive material such as a photoresist is applied on a substrate such as a semiconductor wafer or a glass substrate, and a reticle pattern is transferred onto the photosensitive material. In this case, since an appropriate exposure amount is determined for the photosensitive material, the conventional exposure apparatus controls the exposure amount on the photosensitive substrate to be an appropriate exposure amount as follows.

That is, first, a reticle on which a pattern to be exposed is drawn is mounted on an exposure apparatus,
Exposure (test print) is performed on the photosensitive substrate while changing each condition little by little in order to obtain an appropriate focus position and an appropriate exposure amount, and the pattern formed on the photosensitive material is subjected to an optical microscope or a scanning electron microscope. Observe the optimum conditions by using the above method. However, this operation need not be performed for a reticle for which the optimum conditions are known in advance.

Thereafter, when actually exposing the photosensitive substrate, the exposure amount is controlled using an integrator sensor including a photoelectric conversion element provided in an illumination optical system of the exposure apparatus. The integrator sensor is arranged at a position substantially conjugate with a secondary light source forming surface of a fly-eye lens as an optical integrator also in the illumination optical system, and is irradiated to the photosensitive substrate side via the fly-eye lens. Part of the exposure light is guided to the integrator sensor by the beam splitter. At this time, the conversion coefficient from the photoelectric conversion signal of the integrator sensor to the exposure energy on the photosensitive substrate is obtained in advance, and the photoelectric conversion signal of the integrator sensor is integrated and multiplied by the conversion coefficient to obtain the conversion coefficient on the photosensitive substrate. An integrated exposure energy is required. Then, when the integrated exposure energy reaches an appropriate exposure amount, the exposure light on the photosensitive substrate is controlled by shielding the exposure light with a shutter or the like.

[0005] In the case of a conventional ordinary illumination optical system, the relationship between the photoelectric conversion signal of the integrator sensor and the exposure energy on the photosensitive substrate is almost constant and simple. Good results were also obtained with the method. In this regard, in recent years, circuit patterns such as LSIs have been miniaturized, and there has been an increasing demand for exposing finer patterns on a photosensitive substrate with high resolution. One of the techniques to respond to this is the numerical aperture (NA) of the projection optical system.
, But because it has its limits,
Recently, the following various other attempts have been made.

First, in a method called a phase shift method disclosed in Japanese Patent Publication No. 62-50811, for example, a phase film is provided between chromium patterns or the like in order to shift the phase of light passing through a reticle. Exposure is performed using a phase shift reticle. In this phase shift method, the so-called σ value, which is a coherency factor of the illumination optical system, has a great influence on the imaging performance. In order to form a finer pattern, the σ value is set to a relatively small value. Is done.

Further, an actual semiconductor device is usually formed by superposing circuit patterns of 20 layers or more. However, since the resolution required for the circuit patterns of each layer is different, a normal reticle and a phase shift reticle are different from each other. Are likely to be mixed. Accordingly, for example, Japanese Patent Application Laid-Open No. 2-50417
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, an exposure apparatus having an illumination optical system having a variable σ value is required. As a method of changing the σ value, for example, near the exit surface of the fly-eye lens in the illumination optical system, that is, the Fourier transform plane (pupil plane) of the illumination optical system
Is used to open and close an aperture stop provided in the vicinity of. When the σ value is changed in this manner, the amount of light incident on the integrator sensor naturally changes, and the exposure amount control is performed based on the changed amount of light.

Another method for improving the imaging characteristics of a pattern exposed on a photosensitive substrate by changing the configuration of an illumination optical system is an annular illumination method (for example, Japanese Patent Application Laid-Open No. 61-91).
662) or a so-called modified light source method (see, for example, JP-A-4-268715). In the annular illumination method, the distribution of the secondary light source on the Fourier transform surface of the illumination optical system becomes annular, and in the modified light source method, the distribution of the secondary light source on the Fourier transform surface of the illumination optical system is the transfer target. Two or four discrete light sources are arranged around the optical axis according to the pattern. Therefore, the distribution state and the coherency factor of the secondary light source on the Fourier transform surface of the illumination optical system are different from those of the ordinary illumination method in any of the illumination methods. Accordingly, the distribution of the amount of light incident on the integrator sensor and the angle of incidence is also changing.

[0009]

In the prior art as described above, the distribution of the incident angle of each light beam of the exposure light guided to the integrator sensor is changed by changing the distribution of the secondary light source on the Fourier transform plane of the illumination optical system. If it changes, the photoelectric conversion signal of the integrator sensor changes according to the distribution of the incident angle even for the same amount of received light, and the sensitivity characteristic of the integrator sensor changes. Therefore, there has been a disadvantage that the exposure energy on the photosensitive substrate cannot be accurately calculated from the photoelectric conversion signal of the integrator sensor.

[0010] In view of the above, the present invention has been developed in consideration of the σ of the illumination optical system.
An object of the present invention is to provide an exposure method and apparatus capable of controlling the exposure energy for a photosensitive substrate to an appropriate exposure amount even when the value or the like is changed to change the light amount distribution on the Fourier transform surface of the illumination optical system. Furthermore, the present invention
Another object of the present invention is to provide a device manufacturing method using the method.
You.

[0011]

SUMMARY OF THE INVENTION First exposure according to the present invention
The equipment consists of illumination optics that illuminates the mask with exposure light from a light source.
And a projection optical system that projects the exposure light onto a photosensitive substrate.
In an exposure apparatus provided with
First photoelectric detection means (8) for receiving a part of the exposure light;
Angle distribution of the exposure light incident on the first photoelectric detection means
From the output signal of the first photoelectric detection means
The conversion coefficient for calculating the exposure amount on the photosensitive substrate is
The exposure coefficient on the photosensitive substrate based on the conversion coefficient.
An exposure amount control means (4, 9) for controlling the amount of light;
It is. In this case, the first photoelectric detecting means is configured to
The surface is arranged almost conjugate with the Fourier transform surface of the illumination optical system
It is desirable to be done. Also, the light passing through the projection optical system
Second photoelectric detecting means (19) for receiving the exposure light of
According to the change of the incident angle distribution, the detection of the second photoelectric detecting means is performed.
Corrects the adjustment of the imaging characteristics of the projection optical system based on the output signal
It is desirable to further include an imaging characteristic control unit that performs the operation.
Further, the second exposure apparatus according to the present invention includes an
An illumination optical system that illuminates the mask with light, and the exposure light is exposed
An exposure apparatus having a projection optical system for projecting onto a substrate
And a second light receiving the exposure light passing through the projection optical system.
Charge detecting means (19) and the second photoelectric detecting means.
The second light in response to a change in the incident angle distribution of the exposure light.
Imaging characteristic of the projection optical system based on the detection signal of the electric detection means
Image quality control means for correcting the adjustment of the image quality.
is there. Next, the first exposure method according to the present invention employs illumination optics.
Illuminating the mask with exposure light from a light source through the system
Then, the photosensitive substrate is exposed to the exposure light through the projection optical system.
Exposure light passing through the illumination optical system in the exposure method
Is received by the first photoelectric detection means (8),
The incident angle of the exposure light incident on the first photoelectric detection means
In response to the change of the cloth, the output signal of the first photoelectric detection means
Conversion factor for calculating the amount of exposure on the photosensitive substrate
Is determined, and based on the conversion coefficient,
This controls the exposure amount. In this case, the projection optics
Receiving light the exposure light passing through the system at the second photoelectric detecting means (19)
And, depending on the change in the incident angle distribution,
(2) The connection of the projection optical system based on the detection signal of the photoelectric detection means
It is desirable to correct the adjustment of the image characteristics. In addition, the present invention
Is a method of exposing a light source through an illumination optical system.
The mask is illuminated with the exposure light of
Exposure method to expose the photosensitive substrate with the exposure light
And transmits the exposure light passing through the projection optical system to a second photoelectric detection means.
Receiving light at the stage (19) and the second photoelectric detecting means thereof;
In accordance with the change in the incident angle distribution of the exposure light
Projection optical system based on the detection signal of the second photoelectric detection means
The adjustment of the imaging characteristics is corrected. Next, the present invention
The device manufacturing method according to any one of the exposure apparatus of the present invention,
Or photolithography using any of the exposure methods of the present invention
It includes a luffy step. Next, as shown in FIG. 1, for example, as shown in FIG. 1, a third exposure device of the present invention includes an illumination optical system (1, 3, 12), the pattern for transfer is exposed on the photosensitive substrate (15), and the photosensitive substrate (1) is exposed.
5) Input means (22) for inputting a state of distribution of the exposure light on the Fourier transform surface of the illumination optical system in an exposure apparatus which controls the integrated exposure amount of the exposure light upward to an appropriate exposure amount. And illumination state changing means (10, 5) for setting the distribution state of the input exposure light by the illumination optical system.

Further, a third exposure apparatus of the present invention is a photoelectric conversion means for receiving a part of the exposure light generated by the illumination optical system near a plane conjugate with the Fourier transform plane of the illumination optical system. (8) and a conversion coefficient for obtaining the exposure amount on the photosensitive substrate (15) from the output signal of the photoelectric conversion means (8)
It is stored in advance as a function for the distribution state of the exposure light on the Fourier transform plane of the illumination optical system, and the output signal of the photoelectric conversion means (8), the distribution state of the exposure light input from the input means (22), and the Exposure amount calculating means (21) for calculating the integrated exposure amount of the exposure light to the photosensitive substrate (15) from the stored conversion coefficient, and the integrated exposure amount calculated by the exposure amount calculating means (21) is used to determine the proper exposure value. Exposure control means (4, 9) for stopping exposure to the photosensitive substrate (15) when the exposure amount is reached.

[0013]

According to the present invention, according to the mask (13), its illumination optical system is changed to any one of an ordinary illumination method, an illumination method corresponding to a phase shift method, an annular illumination method, a modified light source method, and the like. In order to set the illumination method, for example, the input means (22) inputs the exposure amount calculation means (21) to the Fourier transform plane (pupil plane) of the illumination optical system in the illumination method.
Input the distribution state of the exposure light in the step. In this case, when the illumination method changes, the distribution state of the incident angle of the exposure light received by the photoelectric conversion means (8) changes, so that the relationship between the output signal and the exposure amount on the photosensitive substrate (15) is shifted. come.

Therefore, the exposure calculating means (21) uses the conversion coefficient determined in advance as a function for the distribution state of the exposure light on the Fourier transform surface of the illumination optical system, and outputs the output of the photoelectric conversion means (8). From the signal, the photosensitive substrate (1
5) Obtain the above exposure amount accurately. Then, when the integrated value of the exposure amount reaches the appropriate exposure amount, the exposure amount control means (4, 9) stops the exposure, so that the integrated exposure to the photosensitive substrate (15) is always performed regardless of the illumination method. The amount can be set to an appropriate exposure amount.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the exposure apparatus according to the present invention will be described below with reference to the drawings. In the present embodiment, the present invention is applied to a projection exposure apparatus that can change the illumination method of the illumination optical system according to the reticle. FIG. 1 shows a projection exposure apparatus of the present embodiment. In FIG. 1, exposure light emitted from a mercury lamp 1 is condensed by an elliptical mirror 2 and then converted into a substantially parallel light beam by an input lens (not shown). The light is converted and enters the fly-eye lens 3. As a light source for the exposure light, an excimer laser light source or the like can be used in addition to a mercury lamp. A shutter 4 is disposed in an optical path between the mercury lamp 1 and the fly-eye lens 3 so as to be freely inserted and removed, and the shutter 4 controls an exposure amount on the photosensitive substrate.

Rear side of fly-eye lens 3 (reticle side)
A number of secondary light sources are formed on the focal plane, and a variable aperture stop 5 is arranged on the secondary light source forming surface. The arrangement surface of the variable aperture stop 5 is also a Fourier transform surface (pupil surface) of the illumination optical system of the present example, and by changing the distribution state of the secondary light source on the Fourier transform surface by the variable aperture stop 5, Optimize the illumination method for the reticle. That is, the variable aperture stop 5 can set the coherency factor (σ value) of the illumination optical system to a desired value, and can also realize, for example, an annular illumination method or a so-called deformed light source method. Note that, instead of changing the shape and size of the aperture of the variable aperture stop 5, the aperture may be replaced with another aperture stop.

Exposure light I passing through the aperture of the variable aperture stop 5
L is a beam splitter 6 having a high transmittance and a low reflectance.
And the exposure light reflected by the beam splitter 6 is incident on the light receiving surface of an integrator sensor 8 composed of a photoelectric conversion element (such as a silicon photodiode) by a condenser lens 7. In this case, the arrangement surface of the variable aperture stop 5, that is, the Fourier transform surface of the illumination optical system and the light receiving surface of the integrator sensor 8 are substantially conjugated by the condenser lens 7. The output signal of the integrator sensor 8 is supplied to the exposure control unit 9, and the exposure control unit 9 controls the opening and closing operation of the shutter 4. Also, the illumination system control unit 10 sets the shape and size of the aperture of the variable aperture stop 5 to the specified state.

Exposure light I transmitted through beam splitter 6
After L is reflected vertically downward by the mirror 11, it is condensed by the main condenser lens 12 and illuminates the reticle 13 with uniform illuminance. The image of the pattern formed on the reticle 13 is reduced at a predetermined reduction magnification via the projection optical system 14, and is projected and exposed on a wafer 15 coated with a photosensitive material.

A variable aperture stop 16 is disposed on the Fourier transform plane (pupil plane) of the projection optical system 14, and a numerical aperture control unit 17 controls the state of the aperture of the variable aperture stop 16 so that the projection optical system 14 is controlled. The numerical aperture (NA) of the system 14 is set to a predetermined value. The wafer 15 is placed on a wafer stage 18. The wafer stage 18 is positioned on an XY stage for positioning the wafer 15 in a plane perpendicular to the optical axis of the projection optical system 14, and in the direction of the optical axis of the projection optical system 14. It comprises a Z stage for positioning the wafer 15 and the like. In addition, an irradiation amount monitor 19 made of a photoelectric conversion element is arranged near the wafer 15 on the wafer stage 18, and when the exposure energy passing through the projection optical system 14 is directly obtained, the exposure operation on the wafer 15 is started. Before that, the exposure monitor 19 is moved to the exposure field of the projection optical system 14 to measure the exposure light.

The detection signal from the irradiation amount monitor 19 is supplied to a lens controller 20 and the lens controller 20
Is controlled by the central controller 21. The central controller 21 controls the operations of the exposure controller 9, the illumination system controller 10, and the numerical aperture controller 17, and supplies the opening / closing information of the shutter 4 from the exposure controller 9 to the lens controller 20. In general, when the exposure light continuously passes through the projection optical system 14, the arrangement and shape of the lens elements constituting the projection optical system 14 change due to the irradiation energy of the exposure light, and the imaging characteristics of the projection optical system 14 are changed. Is known to fluctuate over time. Then, the lens controller 20 obtains the detection signal of the irradiation amount monitor 19 which has been measured in advance, and the opening / closing information of the shutter 4 which is constantly supplied.
The temporal variation of the imaging characteristics of the projection optical system 14 is constantly monitored. Further, the lens controller 20 corrects the imaging characteristic of the projection optical system 14 so that the fluctuation of the imaging characteristic falls within a predetermined allowable range.

The temporal variation of the imaging characteristics of the projection optical system 14 includes, for example, a magnification variation and a focus variation. Lens controller 2 to correct magnification fluctuation
0 is to change the pressure of some lens chambers in the projection optical system 14 to change the refractive index of air in the lens chambers,
Alternatively, some lenses in the projection optical system 14 are moved. To correct the focus fluctuation, the lens controller 20 adds an offset to a focus system (not shown) so that the position of the wafer stage 18 in the optical axis direction of the projection optical system 14 at the time of exposure is set to a desired height. To

An input device 22 composed of a keyboard is connected to the central processing unit 21. The operator specifies the distribution state of the secondary light source on the Fourier transform plane of the illumination optical system from the keyboard 22 to the central processing unit 21. However, the type of the reticle 13 and the minimum pitch of the pattern to be transferred are input from the input device 22 to the central processing unit 21 so that the central processing unit 2
On the one side, the distribution state of the optimal secondary light source on the Fourier transform plane of the illumination optical system may be obtained from the information. As the input device 22, for example, an input device including a CRT display and a so-called mouse, or a data file storing various exposure conditions (eg, exposure area, exposure energy, focus position offset, etc.) may be used. Can also. In FIG. 1, the exposure control unit 9 and the lens controller 20 are connected via the central processing unit 21. However, the exposure control unit 9 and the lens controller 20 may be integrated as a control unit from the beginning. It is possible.

Next, an example of the exposure operation of the projection exposure apparatus of this embodiment will be described. First, in FIG. 1, when the reticle 13 is the phase shift reticle described above, it is necessary to perform exposure with a small σ value of the illumination optical system. Therefore, the operator inputs the σ value of the illumination optical system to the central processing unit 21 via the input device 22. However, from the input device 22, information on the pattern density on the reticle and whether or not the reticle is a phase shift reticle is input to the central processing unit 1
2 may automatically determine the σ value. The central processing unit 12 specifies the σ value to the illumination system control unit 10, and the illumination system control unit 10 sets the aperture diameter of the variable aperture stop 5 to a value corresponding to the σ value.

Similarly, when the reticle 13 is, for example, a normal reticle and the minimum pitch of the pattern is extremely small, exposure is performed by setting the illumination optical system to the annular illumination method or the modified light source method. There is a need. Then, the operator specifies the annular illumination method or the modified light source method or the like to the central processing unit 21 via the input device 22 so that the illumination system control unit 10 changes the shape of the opening of the variable aperture stop 5 to the corresponding shape. Set to.

At this time, part of the exposure light that has passed through the variable aperture stop 4 is reflected by the beam splitter 6 and enters the light receiving surface of the integrator sensor 8, and the photoelectric conversion signal of the integrator sensor 8 is sent to the exposure controller 9. Supplied. The exposure control unit 9 calculates the exposure (exposure energy) on the wafer 15 from the photoelectric conversion signal of the integrator sensor 8.
Is calculated indirectly, and when the exposure amount reaches a predetermined appropriate exposure amount for the wafer 15, the shutter 4 is closed. However, the distribution of the angle of incidence of the light beam incident on the integrator sensor 8 varies depending on the shape and size of the aperture of the variable aperture stop 5, and a conversion coefficient for obtaining the exposure amount on the wafer 15 from the photoelectric conversion signal of the integrator sensor 8. Is also different. Therefore, a conversion coefficient previously obtained as a function of the shape and size of the aperture of the variable aperture stop 5 is stored in the exposure control unit 9.

With reference to FIGS. 2 and 3, the manner in which the conversion coefficient changes will be specifically described. First, FIG.
FIG. 2A shows a case where the σ value of the illumination optical system is large.
3 shows the case where the σ value of the illumination optical system is small, and FIG. 3 shows the case where the illumination optical system uses the modified light source method. The light receiving surface of the integrator sensor 8 is almost conjugate with the arrangement surface of the variable aperture stop 5. For example, comparing FIG. 2A and FIG. 2B, it can be seen that the distribution of the incident angle of the incident light on the integrator sensor 8 and the size of the light spot on the light receiving surface of the integrator sensor 8 change. Also in FIG. 3, the distribution of the incident angle of the light on the light receiving surface of the integrator sensor 8 and the distribution shape of the light are changed.

As the integrator sensor 5, for example, a photoelectric conversion element such as a silicon photodiode (SPD) is used. The photoelectric conversion signal of such a photoelectric conversion element generally has an angle-dependent characteristic depending on the incident angle and a light receiving surface. There is uneven sensitivity due to the upper position. Therefore, FIG. 2 or FIG.
When the distribution state of the secondary light source on the Fourier transform surface of the illumination optical system changes as in the above, accurate exposure amount control cannot be performed.

Therefore, the exposure control unit 9 in FIG. 1 performs the correction by simultaneously obtaining the distribution information of the secondary light sources output from the central processing unit 21 to the illumination system control unit 10. That is, the exposure controller 9 does not use the output of the integrator sensor 8 as it is, but obtains in advance a series of conversion coefficients that change according to the distribution state of the secondary light source, and uses the conversion coefficients to calculate the photoelectric conversion of the integrator sensor 8. The exposure amount on the wafer 15 is calculated from the conversion signal. Then, by controlling the open / close state of the shutter 4 based on the integrated value of the exposure amount, accurate exposure amount control becomes possible. Also, in the case of using, for example, an annular illumination method in addition to the modified light source method, since the state of the aperture of the variable aperture stop 5 changes, accurate exposure amount control can be performed by performing the same correction. The same applies to the case where the variable aperture stop 5 is replaced instead of changing the aperture of the variable aperture stop 5.

In the above embodiment, the correction for the output of the integrator sensor 8 has been considered. However, the same phenomenon occurs for the dose monitor 19. That is, for example, when a phase shift reticle is used as the reticle 13, the 0th-order component of the exposure light after passing through the reticle disappears, and a pattern image of the reticle is formed by the diffracted ± 1st-order diffracted light. Accordingly, the light incident on the irradiation amount monitor 19 has many components that are inclined and the output obtained by the irradiation amount monitor 19 is different even if the same amount of light passes through the projection optical system 14. In this case, the lens controller 20 may perform the same correction as that performed by the exposure controller 9. It is also effective to perform similar correction depending on the state of the variable aperture stop 16.

The present invention is not limited to the above embodiment,
It goes without saying that various configurations can be taken without departing from the gist of the present invention.

[0031]

According to the present invention, the conversion coefficient for determining the amount of exposure on the photosensitive substrate is changed according to the light amount distribution on the Fourier transform surface of the illumination optical system. Even if the light amount distribution on the Fourier transform surface of the illumination optical system is changed by changing the above, there is an advantage that the exposure energy for the photosensitive substrate can be controlled to an appropriate exposure amount. Therefore, it is not necessary to perform a test print for obtaining the optimum exposure condition every time the illumination optical system is changed as in the related art.

[Brief description of the drawings]

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

FIG. 2A is an optical path diagram showing a state of a light flux reaching an integrator sensor 8 when a σ value of an illumination optical system is large,
(B) is an optical path diagram showing a state of a light beam reaching the integrator sensor 8 when the σ value of the illumination optical system is small.

FIG. 3 is an optical path diagram showing a state of a light beam reaching an integrator sensor 8 when the illumination optical system uses a modified light source method.

[Explanation of symbols]

 Reference Signs List 3 fly-eye lens 4 shutter 5 variable aperture stop 8 integrator sensor 9 exposure amount control unit 10 illumination system control unit 12 main condenser lens 13 reticle 14 projection optical system 15 wafer 16 variable aperture stop 19 irradiation amount monitor 20 lens controller 21 central processing unit 22 Input device

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/027 G03F 7/20

Claims (23)

(57) [Claims] 1. An exposure apparatus comprising: an illumination optical system for illuminating a mask with exposure light from a light source; and a projection optical system for projecting the exposure light onto a photosensitive substrate, wherein the exposure light passing through the illumination optical system First to receive part of
A photoelectric detection unit, for calculating an exposure amount on the photosensitive substrate from an output signal of the first photoelectric detection unit in accordance with a change in an incident angle distribution of the exposure light incident on the first photoelectric detection unit. An exposure control means for determining a conversion coefficient and controlling an exposure amount on the photosensitive substrate based on the conversion coefficient. 2. An exposure apparatus according to claim 1, wherein said first photoelectric detecting means has a light receiving surface arranged substantially conjugate with a Fourier transform surface of said illumination optical system. 3. A second photoelectric detection means for receiving the exposure light passing through the projection optical system, and the projection optical system based on a detection signal of the second photoelectric detection means according to a change in the incident angle distribution. The exposure apparatus according to claim 1, further comprising: an imaging characteristic control unit configured to correct adjustment of the imaging characteristic. 4. A lighting optical system for illuminating a mask with exposure light from a light source, an exposure apparatus having a projection optical system for projecting the exposure light on the photosensitive substrate, the exposure light passing through the projection optical system And an imaging of the projection optical system based on a detection signal of the second photoelectric detection means according to a change in an incident angle distribution of the exposure light incident on the second photoelectric detection means. An exposure apparatus comprising: an imaging characteristic control unit that corrects adjustment of characteristics. Wherein said second photoelectric detecting means, an exposure apparatus according to claim 3 or 4, characterized in that it comprises a photoelectric element arranged on the image plane side with respect to the projection optical system. 6. The projection optical system according to claim 3 , further comprising a stop for changing a numerical aperture of the projection optical system, wherein the incident angle distribution is changed by changing the numerical aperture. Exposure apparatus according to the above. 7. An optical member for changing a distribution state of the exposure light on a Fourier transform surface of the illumination optical system,
The exposure apparatus according to claim 1, wherein the incident angle distribution changes by changing the distribution state. Wherein said optical member, an exposure apparatus according to claim 7, characterized in that to change the distribution state in accordance with the information of the pattern to be transferred onto the photosensitive substrate. 9. The optical member according to claim 1 , wherein the distribution state is changed such that a coherency factor of the illumination optical system is changed, or an annular illumination method or a modified light source method is performed. Item 7. The exposure apparatus according to Item 7 or 8. 10. The optical member according to claim 7, wherein the optical member distributes the exposure light on the Fourier transform plane outside the optical axis of the illumination optical system in accordance with a pitch of the pattern. The exposure apparatus according to claim 1. 11. The optical member includes a plurality of optical elements used for changing the distribution state, and the plurality of optical elements are respectively replaced and arranged in the illumination optical system. Item 11. The exposure apparatus according to any one of Items 7 to 10. 12. The illumination optical system includes an optical integrator for forming a secondary light source on the Fourier transform plane with the exposure light from the light source, the optical member, the shape and size of the secondary light source The exposure apparatus according to claim 7, wherein the exposure apparatus is changeable. 13. An element manufacturing method, comprising a photolithography step using the exposure apparatus according to claim 1. Description: 14. An exposure method for illuminating a mask with exposure light from a light source through an illumination optical system and exposing a photosensitive substrate with the exposure light via a projection optical system, wherein the exposure light passing through the illumination optical system is A part of the light is received by the first photoelectric detection means, and the first light is received in accordance with a change in the incident angle distribution of the exposure light incident on the first photoelectric detection means.
An exposure method comprising: determining a conversion coefficient for calculating an exposure amount on the photosensitive substrate from an output signal of a photoelectric detection unit; and controlling the exposure amount on the photosensitive substrate based on the conversion coefficient. . 15. The projection optical system according to claim 2, wherein the exposure light passing through the projection optical system is received by a second photoelectric detection unit, and based on a detection signal of the second photoelectric detection unit in accordance with a change in the incident angle distribution. 15. The exposure method according to claim 14, wherein the adjustment of the image forming characteristics is corrected. 16. An exposure method for illuminating a mask with exposure light from a light source through an illumination optical system and exposing a photosensitive substrate with the exposure light via a projection optical system, wherein the exposure light passing through the projection optical system is An image of the projection optical system is received based on a detection signal of the second photoelectric detection unit in accordance with a change in an incident angle distribution of the exposure light incident on the second photoelectric detection unit, while being received by the second photoelectric detection unit. An exposure method, wherein the adjustment of characteristics is corrected. 17. The apparatus according to claim 1 , wherein the distribution of the incident angle is changed by changing a numerical aperture of the projection optical system.
The exposure method according to 4, 15 or 16. 18. The method according to claim 14 , wherein the distribution of the incident light is changed by changing a distribution state of the exposure light on a Fourier transform plane of the illumination optical system. Exposure method according to the above. 19. The exposure method according to claim 18, wherein the distribution state is changed according to information on a pattern to be transferred onto the photosensitive substrate. 20. The method according to claim 18, wherein the coherency factor of the illumination optical system is changed, or the distribution state is changed so that an annular illumination method or a modified light source method is performed. Exposure apparatus according to the above. 21. The method according to claim 18, wherein the exposure light is distributed outside the optical axis of the illumination optical system on the Fourier transform plane in accordance with a pitch of the pattern. Exposure method according to the above. 22. The exposure method according to claim 18, wherein a plurality of optical elements used for changing the distribution state are exchanged and arranged in the illumination optical system. . 23. A method for manufacturing an element, comprising a photolithography step using the exposure method according to any one of claims 14 to 22.