JP2002075843A - Exposure system, method of manufacturing device, and illuminator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form wirings which are formed in orthogonal directions with almost equal line widths under various conditions. SOLUTION: In an exposure system which projects the image of a pattern formed on a mask upon a substrate by illuminating the mask with light emitted from a light source and sent through an optical illumination system, a diaphragm device 60 which has an opening 90 for shaping the cross-sectional shape of the light and changes the ratio of the length of the opening 90 in the X-axis direction to that of the opening 90 in the Y-axis direction is provided on the pupil plane of the optical illumination system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and an illuminating apparatus used in a photolithography step which is one of the steps for manufacturing a device such as a semiconductor integrated circuit or a liquid crystal display element, and a device manufactured using the exposure apparatus. And a device manufacturing method for the device.

[0002]

2. Description of the Related Art Microprocessors and DRAMs (Dyna
Devices such as a semiconductor integrated circuit such as a mic random access memory) or a liquid crystal display device are generally manufactured using a photolithography technique. The photolithography technique illuminates a mask or reticle (hereinafter, also referred to as a “mask”) on which a fine pattern is formed with illumination light, and converts an image of the pattern formed on the mask into a photosensitive material such as a photoresist. This is a technique of transferring onto a photosensitive substrate such as a semiconductor wafer or a glass plate coated with an agent.

As an exposure apparatus used in the photolithography technology, a photosensitive substrate is placed on a two-dimensionally movable stage, and the photosensitive substrate is stepped by this stage to form a mask pattern image. 2. Description of the Related Art A step-and-repeat reduction projection exposure apparatus (stepper) that repeats an operation of sequentially exposing and transferring exposure to each shot area on a photosensitive substrate is often used. In recent years, a step-and-scan type exposure apparatus that synchronously scans a mask and a substrate during exposure to perform exposure has also been used. The exposure apparatus includes an ultrahigh-pressure mercury lamp, an excimer laser, or the like as a light source of the illumination light, and is provided with an illumination optical system that equalizes the illuminance of the illumination light emitted from the light source and shapes the cross-sectional shape.

In manufacturing a semiconductor integrated circuit, a large number of identical semiconductor integrated circuits are usually formed on a single semiconductor substrate. Therefore, a step-and-repeat type exposure apparatus is often used. Under the current situation where the circuit area is increased, a step-and-scan type exposure apparatus is often used. Generally, a plurality of fine wirings are formed in parallel in a semiconductor integrated circuit. For example, the interval (pitch) between wirings formed in a logic device such as a microprocessor is very important for the degree of integration. It is set to be relatively large as compared with the distance between wirings formed in a DRAM or the like. Therefore, in order to manufacture a logic device that performs stable high-speed operation, uniformity of isolated line width in an integrated circuit is important.
The performance of microprocessors manufactured in recent years has been dramatically improved, the operating frequency has reached the giga order, and miniaturization has been progressing from the viewpoint of miniaturization and low power consumption. Under such circumstances, it has become difficult to make the isolated line width uniform.

[0005]

In general, a semiconductor integrated circuit is finely divided along a vertical direction (for example, Y-axis direction) and a horizontal direction (for example, X-axis direction) in a plane of a photosensitive substrate. In this structure, various wirings are formed, and these wirings are stacked in the thickness direction of the photosensitive substrate.
Here, the line width uniformity of the wiring formed in the semiconductor integrated circuit means the width of the wiring (vertical wiring) along the vertical direction and the wiring (horizontal wiring) along the horizontal direction at a plurality of positions in the integrated circuit. And the variation of these line widths. Normally, the width of the vertical wiring and the width of the horizontal wiring are not the same but are somewhat different. As the cause, the following causes (1) to (3) can be considered.

[0006] (1) Deviation from the ideal state of the illumination optical system (a state in which the illumination light illuminated on the mask is completely uniform) (2) When the exposure apparatus has a projection optical system, Deviation from ideal imaging state due to aberration (3) Positioning error between mask and wafer or synchronization control error between mask and wafer When vertical wiring width and horizontal wiring width are not the same Is the difference (VH) between the average width of the vertical wiring and the average width of the horizontal wiring over the entire integrated circuit.
A line width difference “HV”) may occur. Usually, the value of the VH line width difference “HV” is required to be equal to or less than a specific value (usually 0) in order to improve device operation characteristics. Therefore, it is convenient if the exposure apparatus can control only the value of the VH line width difference “HV”. However, conventionally, an optical system and a control system are required to reduce the overall line width variation of the integrated circuit. Although optimized, it is rare to optimize a specific member in the exposure apparatus to control only the value of the VH line width difference “HV”. In the future, particularly in the production of semiconductor integrated circuits, it is required to further reduce the width of the wiring.
It is desired to set the value of the line width difference “HV” to a value equal to or less than a specific value.

The present invention has been made in view of such a problem of the prior art, and the line widths of wirings formed in directions perpendicular to each other can be made substantially the same even under various circumstances. An object of the present invention is to provide an exposure apparatus and an illumination apparatus, and further provide a method for manufacturing a device manufactured using the exposure apparatus.

[0008]

Hereinafter, in the examples shown in this section, for ease of understanding, each constituent element of the present invention will be described with typical reference numerals shown in the drawings of the embodiments. The configuration of the present invention or each component requirement is not limited to those restricted by these reference numerals.

In order to solve the above-mentioned problems, an exposure apparatus according to the present invention emits light from a light source (10) and uses an illumination optical system (20,
30, 40, 50, 60) of the illumination light (I
L) illuminates the mask (M) and projects an image of the pattern formed on the mask (M) onto the substrate (W) in an opening for shaping the cross-sectional shape of the illumination light (IL) ( 61, 90, 97, 106), and the first of the openings
A diaphragm device (6) that changes the ratio between the length in the direction (X-axis direction) and the length in a second direction (Y-axis direction) orthogonal to the first direction.
0) with the illumination optical system (20, 30, 40, 50, 6).
0) is provided on the pupil plane.

According to the present invention, a diaphragm device for changing the ratio of the length in the first direction and the length in the second direction orthogonal to each other of the opening for shaping the sectional shape of the illumination light is provided on the pupil plane of the illumination optical system. Since the ratio of the length of the cross section of the illumination light in the first direction to the length of the cross section of the illumination light in the second direction is variable, the exposure amount in the first direction and the exposure amount in the second direction can be adjusted. In addition, the line widths of the wirings formed in the first direction and the second direction orthogonal to each other can be formed substantially the same even under various circumstances.

In other words, according to the present invention, the illumination optical system can be shaped into an ideal state (for example, illumination light having a circular cross section and a uniform illuminance distribution, and as a result, is optimized for dense wiring. State), the σ value (diameter of the stop) in the first direction and the σ value in the second direction are changed. This is because, when an isolated line is formed, its width monotonically decreases with an increase in the effective σ value in a direction orthogonal to the isolated line.

However, the relationship between the line width and the effective .sigma. Value generally differs depending on the pattern pitch. When patterns having different pitches are formed, attention is paid to the pattern of a specific pitch, and the VH line of the pattern is focused on. Optimize width difference. The relationship between the line width and the effective σ value is remarkable for an isolated line, but even in a dense line, the line width depends on the effective σ value. Therefore, the VH line width difference is not necessarily improved for a pattern in which the VH line width difference is not optimized, and may be worse in some cases.

However, a pattern formed by integration is generally classified into a relatively large pitch classified as an isolated line and a line: space = 1: 1 called a dense line or a peripheral pitch. You. In actual use, dense line VH
Since the isolated line VH line width difference is often optimized so that the line width difference is not extremely deteriorated, it is sufficiently practical to control the VH line width difference by giving anisotropy to the effective σ value. .

Here, it is preferable that the diaphragm device (60) has the following configuration [1] to [3].

[1] A pair of linear portions (8) arranged to face each other along the first direction (X-axis direction, d1)
3a, 84a, 83b, 84b) and a pair of aperture shaping plates (80a, 80b) each having an arc portion (85a, 85b) continuous with the linear portion. The linear portions are arranged symmetrically so as to overlap with each other, and are slidably supported in a direction substantially parallel to the first direction.

[2] The first direction (X-axis direction, d11)
(92a, 92b, 93c, 93d) along the second direction (Y-axis direction, d12).
a, 93b, 92c, 92d) and the straight portions (92a to 92a).
92d, 93a to 93d) and four aperture shaping plates (91a) each having an arc portion (94a to 94d) continuous therewith.
To 91d), wherein the aperture shaping plates are arranged in a substantially annular shape so that a part of the opposing linear portions of the adjacent aperture shaping plates overlap with each other, and the first direction and the second direction are arranged.
Slidably in directions substantially parallel to the respective directions.

[3] The first direction (X-axis direction, d21)
(101a to 101d) and a pair of arc portions (102a to 102d) connected to both ends of the straight portion.
2d, 103a to 103d) and four opening shaping plates (100a to 100d), and the opening shaping plates are formed in a substantially annular shape such that a part of the opposing arc portions of the adjacent opening shaping plates overlap with each other. The length of the opening (106) in the first direction decreases as the length of the opening (106) decreases, and the length of the opening (106) in the first direction increases. In the second direction (the length is reduced so that the length is reduced.

In the above [1] to [3], the aperture shaping plates (80a, 80b, 91a to 91d, 100
a to 100d), the openings (90, 97, 10).
A rotation table (81) for rotating the aperture shaping plate in the section of the illumination light (IL) in a state where the shape of 6) is determined.
Can be provided.

Further, in the exposure apparatus according to the present invention, the stop device (60) may be configured such that the apertures have different ratios between the length in the first direction (X-axis direction) and the length in the second direction (Y-axis direction). A plurality of aperture members (80a, 80b, 91
a to 91d, 100a to 100d), and an exchange device for selectively arranging any one of the plurality of aperture members on the optical path of the illumination light (IL).

Further, a device manufacturing method of the present invention is characterized by including a step of transferring a device pattern onto a work piece (W) using the above exposure apparatus.

Further, the illumination device of the present invention provides an illumination optical system (20, 30, 40, 50, 6) for uniforming the illuminance distribution of the incident illumination light (IL) and shaping the cross-sectional shape.
0), the openings (61, 90, 97, 10) for shaping the cross-sectional shape of the illumination light (IL).
6), wherein the aperture device changes the ratio of the length of the opening in a first direction (X-axis direction) to the length of a second direction (Y-axis direction) orthogonal to the first direction. , Provided on a pupil plane of the illumination optical system.

The exposure apparatus of the present invention has an illumination optical system for irradiating the mask with illumination light from a light source, and transfers the pattern formed on the mask onto a substrate. When including linear elements extending in the first and second directions, respectively, it is defined along one of the first and second directions on the pupil plane of the illumination optical system and is symmetric with respect to the optical axis of the illumination optical system. 2 having a pair of straight parts
An optical device for forming a secondary light source is provided.

[0023] In this case, the optical device may be configured such that the line width difference of the transferred image between the linear element in the first direction and the linear element in the second direction is substantially maintained at a predetermined value. 1
And a difference between the sizes of the secondary light sources in the second direction can be adjusted. Here, the predetermined value means that, for example, when the line width difference is zero, the line width difference falls within a predetermined allowable range around the zero. Further, in the optical device, the length of the pair of linear portions can be made variable. further,
The optical device may form a secondary light source in which the pair of linear portions are connected by an arc portion. In addition, the secondary light source can be set such that the center of gravity of the light amount substantially coincides with the optical axis of the illumination optical system.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an exposure apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG.
1A and 1B are diagrams illustrating a configuration of an exposure apparatus according to an embodiment of the present invention, wherein FIG. 1A is a plan view and FIG. 1B is a side view. In this embodiment, a case where a step-and-scan exposure apparatus is used will be described as an example.

Incidentally, in the following description, FIG.
(B) The XYZ rectangular coordinate system shown in FIG.
The positional relationship of each member will be described with reference to the YZ orthogonal coordinate system. In the XYZ rectangular coordinate system, the XY plane is actually set as a plane parallel to the horizontal plane, and the Z axis is set in a vertically upward direction. Also, in FIG. 1, the optical axis AX is shown as a straight line for simplification and easy understanding of the drawing, but in practice, the optical axis AX is appropriately adjusted using a mirror, a dichroic mirror, or the like. It is bent.

In FIG. 1, a light source 10 emits illumination light IL which is a parallel light beam having a substantially rectangular cross section. Illumination light I
As L, for example, g-line (436 nm), i-line (365
nm) or KrF excimer laser (248 nm), A
rF excimer laser (193 nm), or _{F 2} laser (157 nm) laser light emitted from the like are used. The illumination light IL emitted from the light source 10 enters the beam shaping optical system 20.

The beam shaping optical system 20 has a refractive power in a direction (Y-axis direction) perpendicular to the plane of FIG.
It is composed of two cylindrical lenses 21 and 22. A cylindrical lens 21 arranged on the light source 10 side
Has a negative refractive power and diverges the illumination light IL in the direction of the paper surface of FIG. 1B (Y-axis direction), while the cylindrical lens 22 on the illuminated surface side has a positive refractive power, and the light source 10 Light I diverged by the side cylindrical lens 21
L is collected and converted into parallel light. Therefore, the illumination light IL from the light source 10 via the beam shaping optical system 20 is reflected in FIG.
(B) is shaped into a rectangular shape having an enlarged cross-sectional width in the paper surface direction (Y-axis direction). The beam shaping optical system 20 may be a combination of a cylindrical lens having a negative refractive power, and may be an anamorphic prism or the like.

The illumination light IL shaped by the beam shaping optical system 20 forms an optical integrator 3 which forms a plurality of light source images linearly arranged in three rows along the Y-axis direction.
Incident at 0. FIG. 2A is a front view of the optical integrator 30. As shown in FIG. 2A, the optical integrator 30 is provided with a plurality of biconvex lens elements 30a having a substantially square lens cross section (3 columns × 9 rows = 27 in this example). The optical integrator 30 has a rectangular cross section as a whole. Each biconvex lens element 30a has the same curvature (refractive power) in the X-axis direction and the Y-axis direction.

For this reason, the optical integrator 3
Illumination light IL passing through the individual lens elements 30a constituting 0 is condensed by the lens elements 30a, and a light source image is formed on the emission side of each lens element 30a. Therefore, the emission side position A of the optical integrator 30
₁ includes a plurality (3 rows ×) corresponding to the number of lens elements 30a.
(9 rows = 27) light source images are formed, where a secondary light source is substantially formed.

Light beams from a plurality of secondary light sources formed by the optical integrator 30 are condensed by the relay optical system 40, and are incident on an optical integrator 50 that forms a plurality of light source images. FIG.
(B) is a front view of the optical integrator 50. The optical integrator 50 is shown in FIG.
As shown in the figure, a plurality of biconvex lens elements 50a having a rectangular lens cross section (9 rows × 3 in this example)
The lens elements 50a are configured such that the cross-sectional shape (aspect ratio) is similar to the cross-sectional shape (aspect ratio) of the optical integrator 30. The optical integrator 50 as a whole has a square cross section. Each lens element 50a has the same curvature (refractive power) in the X-axis direction and the Y-axis direction in FIG.

For this reason, the optical integrator 5
The light fluxes from the optical integrator 30 passing through the individual lens elements 50a constituting 0 are respectively condensed, and a light source image is formed on the exit side of each lens element 50a. Thus, on the exit side position A ₂ of the optical integrator 50, a plurality of light source images arranged in a square shape is formed, wherein substantially tertiary light sources are formed on.

Here, the optical integrator 50
The number of the plurality of light source images arranged in a square is formed by setting the number of lens elements 30a constituting the optical integrator 30 to N (N is a natural number) and the number of lens elements 50a constituting the optical integrator 50. (M is a natural number), N × M are formed. That is, since the plurality of light source images formed by the optical integrator 30 are formed at the light source image positions of the respective lens elements 50a constituting the optical integrator 50 by the relay optical system 40, the emission side position A ₂ of the optical integrator 50 Has a total of N
× M light source images are formed.

[0033] The relay optical system 40, the incident surface position _{B 2} of the incidence surface position _{B 1} and the optical integrator 50 of the optical integrator 30 as well as a conjugate, an exit surface position _{A 1} of the optical integrator 30
It is conjugate to the exit surface position A ₂ of the optical integrator 50 and. Position A ₂ where this tertiary light source is formed
Alternatively, a diaphragm device 60 having an opening whose shape can be changed as described later is provided at a position near the diaphragm device 60.

The exit surface position A ₂ of the optical integrator 50 which tertiary light sources are formed is set to the pupil plane of the illumination optical system, the exit surface position A ₂ or throttle device 60 in the vicinity thereof is arranged Therefore, the diaphragm device 60 is arranged on the pupil plane of the illumination optical system. The luminous flux from the tertiary light source shaped into a desired shape by the aperture device 60 is condensed by the condenser optical system 70 and is slit-shaped (rectangular shape having long sides and short sides) on the mask M as an object to be illuminated. ) For uniform illumination. In addition, the beam shaping optical system 20 and the optical integrator 3 described above
0, relay optical system 40, optical integrator 5
0 and the aperture device 60 constitute an illumination optical system.

The mask M is held on a mask stage MS, and a substrate and a wafer W as a work piece are coated with a photosensitive agent as a photoresist on the surface thereof and held on the wafer stage WS. The mask M held on the mask stage MS and the wafer W mounted on the wafer stage WS are arranged conjugate with respect to the projection optical system PL, and the pattern image of the mask M illuminated in a slit shape is projected onto the projection optical system PL. It is projected onto wafer W via system PL. The projection optical system PL has a reduction magnification of, for example, about 1/4 to 1/5, and its optical axis AX is set to be orthogonal to the mask M and the wafer W, respectively. The projection optical system PL has an optical element such as a plurality of lenses, and the glass material of the optical element is selected from optical materials such as quartz and fluorite according to the wavelength of the illumination light IL.

The mask stage MS and the wafer stage WS are provided with a laser interferometer (not shown) for measuring position information in an XY plane perpendicular to the optical axis AX of the projection optical system PL. Is constantly measured.
The mask stage MS is configured to move and minutely rotate in the XY plane of FIG. On the other hand, the wafer stage WS is configured to be movable in the XY plane by a linear motor (not shown) or the like, and is supported by three actuators (for example, a piezo element or a voice coil motor), not shown. A table (not shown) is provided with a wafer holder for holding the wafer W. The three actuators allow the table to move in the optical axis AX direction (Z-axis direction) of the projection optical system PL.
Further, it can be arbitrarily tilted with respect to the XY plane, so that its image plane and the surface of the wafer W can be matched within the depth of focus of the projection optical system PL. The table (or wafer holder) may be configured to be slightly rotated in the XY plane.

The main control system (not shown) drives the mask stage MS and the wafer stage WS to perform the alignment between the mask M and the wafer W based on the measurement result of the laser interferometer, and also performs the actual exposure. Figure 1
As shown in (b), the mask stage MS is designated by the code SD1.
The wafer stage WS is synchronously moved in the direction indicated by the symbol SD2 in the direction indicated by the symbol. Thereby, the mask M
Are sequentially transferred to the wafer W.

Although not shown in FIG. 1, the transmittance (=) is set on a rotatable revolver in the illumination optical system.
A plurality of NDs having different (1-dimming rate) × 100 (%)
It is preferable from the viewpoint of controlling the light intensity of the illumination light IL that an energy rough adjuster provided with a filter is provided and the light intensity of the emitted illumination light IL can be switched in a plurality of stages by rotating the revolver. Alternatively, a revolver similar to this revolver may be arranged in two stages so that the transmittance can be more finely adjusted by a combination of two sets of ND filters. Further, it is preferable that the control parameters (voltage, power, etc.) of the light source 10 be changed so that the light intensity of the illumination light IL emitted from the light source 10 can be continuously finely adjusted.

Next, the stop device 60 provided in this exposure apparatus
Will be described in detail. First, before describing the entire diaphragm device 60, the configuration of the opening of the diaphragm device 60 will be described.

[Structure of Opening of Diaphragm Device] FIG. 3 shows a diaphragm device 60 provided in an exposure apparatus according to an embodiment of the present invention.
FIG. 3 is a view for explaining a configuration of an opening included in FIG. FIG.
As shown in the figure, the opening 61 is formed by bisecting a circle having a radius r by a straight line passing through the center thereof, and inserting a rectangle having a length 2r and a width w between two half circles. It is. In other words, the inner circumference of the opening 61 divides the circumference of the radius r by a straight line passing through the center thereof, and inserts two straight lines of length w between the two halved half circles to form two It has a shape with a continuous semicircle.

[0041] defined in accordance pupil plane throttle device 60 of the illumination optical system having an aperture 61 of the shape, i.e. XYZ orthogonal coordinate system in FIG. 3 on the exit surface position A ₂ of the optical integrator 50 which tertiary light sources are formed Assuming that the light intensity of each of the tertiary light sources formed in the pupil plane is the same when the light sources are arranged in the following relationship, the illumination light passed through the diaphragm device 60 having the opening 61 shown in FIG. The ratio between the σ value of the light IL in the X-axis direction and the σ value in the Y-axis direction is (2r + w): 2r.
Here, the σ value is the diameter of the stop.

Now, the conventional opening SA0 has the circular shape shown in FIG. 3, and its diameter (2R) is 2R = 2r.
+ W. If a diaphragm device 60 having an opening 61 is used instead of the conventional opening SA0, the opening 61
Decreases in the Y-axis direction to a value determined by r / R.
Therefore, when forming the horizontal wiring and the vertical wiring along the X-axis direction and the Y-axis direction, respectively, having the same line width, the isolated line width of the horizontal wiring increases.

Here, when the variation of the σ value is small,
The amount of change in the isolated line width is approximately proportional to the amount of change in the σ value. Now, assuming that the proportional constant between the change amount of the isolated line width and the change amount of the σ value is k, the change amount of the horizontal σ value is Δσ _x , and the change amount of the vertical σ value is Δσ _y , V−H The line width difference ΔHV (= H line width−V line width) can be expressed as ΔHV = −k (Δσ _y −Δσ _x ) / σ ₀ . Here, σ ₀ is a σ value corresponding to a circle having a radius R (the opening SA0 in FIG. 3). Also,
Although the specific value of the proportionality constant k differs for each process,
It can be determined by simulation or experiment for each process.

Therefore, if a VH line width difference ΔHV (> 0) occurs when exposure is performed using the opening SA0, the VH line width difference ΔHV is corrected and the value is set to 0.
In order to achieve this, for example, if the value of w and the value of r shown in FIG. 3 are expressed by the formulas (1) and (2), respectively, the opening 61 having a long shape in the Y-axis direction in FIG. good.

W = 2RΔσ _x / σ ₀ = 2RΔHV / k (1) r = R−w / 2 (2) On the other hand, when ΔHV (<0) occurs, this VH line width In order to correct the difference ΔHV so that the value becomes 0, for example, the value of w and the value of r shown in FIG. 3 are expressed by the equations (3) and (4), respectively, in the X-axis direction in FIG. The opening 61 having a long shape may be used.

W = 2RΔσ _y / σ ₀ = 2R | ΔHV | / k (3) r = R−w / 2 (4) In the case of an isolated line, the VH line width difference is almost equal to that of the aperture device. In many cases, it is determined depending only on the difference between the diameter in the X-axis direction and the diameter in the Y-axis direction of the opening 61 arranged on the pupil plane of the provided illumination optical system. However, in the case of dense lines, it may depend on the σ value itself. That is, the difference between the line width of the isolated vertical line and the line width of the isolated horizontal line (isolated VH line width difference) is the diameter of the opening 61 in the vertical direction (Y-axis direction) and the horizontal direction (X-axis direction). The difference between the line width of the dense vertical line and the line width of the dense horizontal line (dense VH line width difference) is the stop diameter and the vertical direction of the opening 61 (Y-axis direction). ) And the difference between the diameter in the lateral direction (X-axis direction) and the diameter in general.

Therefore, if a large number of openings 61 in which the combinations of the values of r and w shown in FIG. 3 are variously changed are prepared in advance, isolated vertical and horizontal lines are formed on the wafer W. In this case, when an isolated VH line width difference is observed, by correcting the observed isolated VH line width difference and selecting an aperture which does not greatly deteriorate the dense VH line width difference,
A desired VH line width difference correction result can be obtained. This is a case where the isolated VH line width difference is emphasized. If the dense VH line width difference is emphasized, the dense VH line width difference is corrected, and the isolated VH line width difference is increased. What is necessary is just to select an aperture that does not deteriorate. Further, a mechanism for installing any one of these openings 61 in the exposure apparatus shown in FIG. 1 and inserting the selected opening 61 into the optical path of the illumination light IL as necessary is provided in the diaphragm device 60. By keeping
Exposure can be performed using a stop having an aperture 61 that is optimal according to the observed VH line width difference.

FIG. 4 is a perspective view showing a first example of the configuration of the aperture device according to the embodiment of the present invention, and FIG. 5 is a front view of the same. The aperture device 60 shown in FIGS. 4 and 5 has a substantially U-shaped aperture shaping plate 80a, 80.
b, and a rotary table 81 for rotating the aperture shaping plates 80a and 80b in the XY plane. FIG. 6 is a front view showing only the opening shaping plate 80a and the opening shaping plate 80b. The aperture shaping plates 80a and 80b are formed by forming U-shaped notches 82a and 82b in a substantially rectangular plate, respectively.

The notch 82a has a pair of straight portions 83a, 84a arranged opposite to each other so as to extend along the direction indicated by the symbol d1 in the drawing, and a circular arc portion 85a continuous with the straight portions 83a, 84a. Defines its shape. Similarly, the notch portion 82b has a pair of straight portions 83b and 84b and a pair of straight portions 83b and 84b that are arranged so as to face each other along the direction indicated by the symbol d1 in the drawing.
The shape is defined by the circular arc portions 85b which are respectively continuous with. Further, the aperture shaping plate 80a has a pair of holes 86a whose longitudinal directions are set in the direction indicated by the symbol d1.
Similarly, the aperture shaping plate 80b includes a pair of holes 86 whose longitudinal directions are set in the direction indicated by the symbol d1.
b, 87b. As described above, the aperture shaping plate 80b according to the present configuration example has a plane-symmetric relationship with the aperture shaping plate 80a with respect to a plane perpendicular to the direction denoted by the symbol d1.

The aperture device 60 of the first configuration cuts the aperture shaping plates 80a and 80b having the U-shaped notches 82a and 82b shown in FIG. 6 as shown in FIGS. 4 and 5, respectively. The notch portions 82a and 82b are arranged so as to face each other, and the straight portions 83a formed on the aperture shaping plate 80a,
84a and a straight portion 8 formed on the aperture shaping plate 80b
3b and 84b are arranged so as to overlap with each other. With this arrangement, the opening 90 is formed.

The aperture shaping plate 80a has a hole 86
The legs of the T-shaped support members 88a and 89a are penetrated by the a and 87a, and are supported by the rotary table 81. Similarly, the aperture shaping plate 80b has the holes 86b and 87 thereof.
Each of the T-shaped support members 88b and 89b penetrates through b and is supported by the turntable 81. Hole 86
Since a, 87a, 86b, and 87b have a long shape, the aperture shaping plates 80a, 80b have the holes 86a, 87a, 86, respectively.
b and 87b can be continuously slid in the longitudinal direction (in the X-axis direction in the drawings in the arrangement shown in FIGS. 4 and 5).

The rotary table 81 is formed in an annular shape.
The inner diameter is set to a size that does not block the opening 90 even when the shape of the opening 90 is deformed by sliding of the opening shaping plates 80a and 80b. In addition, the rotary table 81
By rotating the aperture shaping plates 80a and 80b in XY
It can be rotated in the plane.

FIG. 7 is a diagram showing a state in which the shape of the opening changes when the opening shaping plates 80a and 80b are slid or rotated in the XY plane. FIG.
(A) shows a straight portion 83 formed on the aperture shaping plate 80a.
a, 84a (see FIG. 6) and the overlapping portion of the linear portions 83b, 84b (see FIG. 6) formed on the aperture shaping plate 80b (the opening shaping plate 80a is in the −X axis direction, and the aperture shaping plate 80b is It is a figure which shows the mode of the opening part 90 formed when each of the opening shaping plates 80a and 80b is slid in the (X-axis direction). As shown in FIG.
When the opening shaping plates 80a and 80b are slid in a direction in which the overlapping portions of the a and 84a and the linear portions 83b and 84b increase, the shape of the opening 90 becomes substantially circular, and
The σ value in the X-axis direction and the σ value in the Y-axis direction of 0 can be set substantially equal.

On the other hand, FIG. 7B shows the linear portions 83a, 84
a (see FIG. 6) and the direction in which the overlap between the straight portions 83b and 84b (see FIG. 6) is reduced (the aperture shaping plate 80a is in the X-axis direction,
The aperture shaping plate 80b is in the −X axis direction).
It is a figure which shows the mode of the opening part 90 formed when each of a and 80b is slid. As shown in FIG. 7B, when the opening shaping plates 80a and 80b are slid in the direction in which the overlapping portions of the straight portions 83a and 84a and the straight portions 83b and 84b decrease, the opening 90 in the Y-axis direction in the drawing is reduced. The length in the X-axis direction can be made longer than the length, so that the ratio between the σ value in the X-axis direction and the σ value in the Y-axis direction can be changed.

FIG. 7C shows the aperture shaping plates 80a and 80b set in the state of FIG.
FIG. 3 is a diagram illustrating a state where the image is rotated 90 degrees in the XY plane using the number 1; As shown in FIG. 7C, the aperture shaping plate 8
By rotating 0a and 80b, the length of the opening 90 in the Y-axis direction can be made longer than the length in the X-axis direction, and the ratio between the σ value in the X-axis direction and the σ value in the Y-axis direction is obtained. Can be set opposite to the case of FIG. 7B.

As described above, the aperture shaping plates 80a, 80
Since b is configured to be continuously slidable, the ratio between the σ value of the opening 90 in the X-axis direction and the σ value in the Y-axis direction can be continuously varied. FIG.
In (c), only the case where the rotary table 81 is rotated by 90 degrees has been described, but it may be configured such that the rotary table 81 can be continuously rotated. In this case, for example, the XY plane It is also possible to use the opening shaping plates 80a and 80b in a direction at an angle of 60 degrees with respect to the X axis and at an angle of 30 degrees with the Y axis.

Further, the aperture shaping plates 80a and 80b are configured to be continuously slidable, and the rotary table 81 is configured to be continuously rotatable. , 80b can be adjusted by sliding or rotating. Specifically, for example, a pattern for measuring a VH line width difference while changing the ratio of the σ value in the X-axis direction to the σ value in the Y-axis direction for each shot to be exposed is formed on one wafer or a plurality of wafers. The VH line width difference for each shot is determined by measuring the pattern transferred to the wafer and the formed pattern. As a result, a shot having an optimum VH line width difference is specified, so that the diameter of the opening 90 in the X-axis direction and Y
The diameter in the axial direction is checked, and the wafer W may be exposed during exposure by setting the diameter in the X-axis direction and the diameter in the Y-axis direction of the opening 90 to a diameter at which an optimum VH line width difference is obtained.

FIG. 8 is a perspective view showing a second example of the configuration of the aperture device according to the embodiment of the present invention, and FIG. 9 is a front view of the same. The diaphragm device 60 shown in FIGS. 8 and 9 has four substantially L-shaped aperture shaping plates 91a.
To 91d. FIG.
It is the front view which showed only 1a-91d. As shown in FIG. 10, the aperture shaping plate 91a includes a straight portion 92a extending in a direction indicated by reference numeral d11 and a straight line portion extending in a direction indicated by reference numeral d12 orthogonal to the direction indicated by reference numeral d11. 9
3a and an arc portion 94a continuous with the straight portions 92a and 93a. Similarly, the aperture shaping plate 91b includes a linear portion 92b along the direction denoted by reference numeral d11, a linear portion 93b along the direction denoted by reference numeral d12, and an arc portion continuous with the linear portions 92b and 93b. 94b.

The aperture shaping plate 91c has a straight portion 92c extending in the direction indicated by the reference symbol d12, a straight portion 93c extending in the direction indicated by the reference symbol d11, and arc portions continuous with the straight portions 92c, 93c, respectively. 94c. Similarly, the aperture shaping plate 91d includes a straight portion 92d extending in a direction indicated by reference symbol d12, a straight portion 93d extending in a direction indicated by reference symbol d11, and an arc portion continuous with the straight portions 92d, 93d. 94d.

In addition, the aperture shaping plate 91a has a hole 95a whose longitudinal direction is set in the direction denoted by d11 and a hole 9a whose longitudinal direction is set in the direction denoted by d12.
6a are formed in the aperture shaping plate 91b, and a hole 95b whose longitudinal direction is set in the direction denoted by d11 and a hole 9 whose longitudinal direction is set in the direction denoted by d12.
6b are formed. Similarly, the aperture shaping plate 91c,
Holes 95c and 95d whose longitudinal directions are set in the direction indicated by reference numeral d12 and holes 96c and 96d whose longitudinal directions are set in the direction indicated by reference numeral d11 are formed in 91d. .

The aperture device 60 of the second configuration is configured so that the aperture shaping plates 91a to 91d shown in FIG.
The linear portions 1a to 91d are arranged in a substantially annular shape so that a part of the opposed straight portions overlap each other. For example, a part of the linear portion 92a of the opening shaping plate 91a and a part of the linear portion 93c of the opening shaping plate 91c overlap each other, and the opening shaping plate 91a
Of the straight portion 93a of the opening portion and the straight portion 92 of the aperture shaping plate 91d.
It is arranged so that a part of d overlaps each other. With this arrangement, the opening 97 shown in FIGS. 8 and 9 is formed.

The head 99a of the T-shaped support member 98a is disposed so as to penetrate the hole 95a formed in the opening shaping plate 91a and the hole 96c formed in the opening shaping plate 91c. A head 99b of a T-shaped support member 98b is arranged to penetrate a hole 95b formed in the plate 91b and a hole 96d formed in the opening shaping plate 91d.
Similarly, a head 99c of a T-shaped support member 98c is disposed to penetrate a hole 95c formed in the opening shaping plate 91c and a hole 96b formed in the opening shaping plate 91b. The head 99d of a T-shaped support member 98d is disposed so as to penetrate through the hole 96a formed in the hole and the hole 95d formed in the opening shaping plate 91d.

As shown in FIG. 8 and FIG.
The heads 99a to 99d of 8a to 98d are provided with aperture shaping plates 91.
holes 95a to 95d, 96a to
It is arranged so as to penetrate along the longitudinal direction of 96d, and supports each of the opening shaping plates 91a to 91d so as to be continuously slidable in the longitudinal direction of the heads 99a to 99d in the XY plane. The support members 98a and 98b are configured to be movable in the Y-axis direction in FIGS.
d is configured to be movable in the X-axis direction in FIGS. 8 and 9.

FIG. 11 is a diagram showing a state where the shape of the opening changes when the opening shaping plates 91a to 91d are slid. FIG. 11A shows a state in which the opening shaping plates 91a to 91d are slid so that the opening 97 becomes the largest. That is, by driving the support members 98a to 98d in the −Y-axis direction, the + Y-axis direction, the −X-axis direction, and the + X-axis direction, the opening shaping plates 91a to 98d are slid to the maximum stroke position. . In this state, the σ value in the Y-axis direction of the opening 97 and the σ value in the X-axis direction
The values are the same.

From this state, for example, when the σ value in the X-axis direction of the opening 97 is set to be small while the σ value in the Y-axis direction is reduced, as shown in FIG.
Set the support member 98a in the + Y axis direction and set the support member 98b in the -Y direction.
By driving in the axial direction, that is, by driving the support members 98a and 98b to a desired position so as to be close to each other, an elliptical opening 97 as shown in the figure can be realized. Further, when it is desired to further reduce the σ value of the opening 97 in the X-axis direction, the supporting members 98a and 98b are similarly driven so as to be closer to each other, so that the opening 97 as shown in FIG. Can be realized.

On the contrary, σ of the opening 97 in the Y-axis direction
When the value is not changed and the σ value in the X-axis direction is set to be small, although not shown in detail, the supporting member 98
By driving c in the + X-axis direction and driving the support member 98d in the -X-axis direction, that is, by driving the support members 98c and 98d to desired positions so as to approach each other,
A desired shape of the opening 97 can be realized.

Further, by simultaneously driving the support members 98a and 98b and the support members 98c and 98d, the .sigma. Value in the X-axis direction and the .sigma. Value in the Y-axis direction of the opening 97 can be freely adjusted. Not only can the ratio of the σ value in the X-axis direction to the σ value in the Y-axis direction of the opening 97 be set arbitrarily, but also the absolute values of the σ values in the X-axis direction and the Y-axis direction can be set arbitrarily. Can be.

In the present configuration example, the σ value in the X-axis direction, the σ value in the Y-axis direction, and their ratio are continuously calculated without using the turntable 81 required in the first configuration example. Can be changed. However, also in this configuration example, the rotary table 8 used in the first configuration example is used.
A rotary table similar to 1 is provided to form aperture shaping plates 91a to 91a.
1d may be rotated in the XY plane. In the case of such a configuration, when the rotary table rotates, the support members 98a to 98d together with the aperture shaping plates 91a to 91d.
Is also configured to rotate. However, the aperture shaping plates 91a-
You may comprise so that only 91d may rotate. At this time, the heads 99a to 99d of the support members 98a to 98d are rotated before rotation.
9d is formed into a hole 9 formed in the aperture shaping plates 91a to 91d.
5a-95d, 96a-96d, once detached, turn the rotary table 90 degrees and open the aperture shaping plates 91a-91d
Is rotated, the heads 99a of the support members 98a to 98d are rotated.
To 99d need to be inserted into holes 95a to 95d and 96a to 96d formed in the aperture shaping plates 91a to 91d.

In the above description, the support members 98a opposed to each other
And 98b and support members 98c and 98d relative to each other,
It is assumed to move in a mirror image. This is to make the center of the opening 97 coincide with the optical axis AX. Therefore, if necessary, support members 98a and 98b and support member 98
It is also possible to move only one of c and 98d, make the other movement amount different from one movement amount, or move both in the same direction.

Generally, the σ value is continuously varied by an iris diaphragm.
According to 0, it is possible to easily realize independently varying the σ value in the X-axis direction and the σ value in the Y-axis direction, which are difficult to realize with the iris diaphragm. Further, in this configuration example, the σ value of the opening 97 is continuously varied by moving all of the support members 98a to 98d and changing the diameter of the opening 97 while maintaining the substantially circular shape. Therefore, although the shape of the opening 97 may not be a perfect circle, there is an advantage that the same effect as the iris diaphragm can be obtained with a simple configuration.

The movement of the support members 98a to 98d may be performed manually, or may be controlled automatically. Further, arc portions 94a to 94d having different curvatures
(See FIG. 10) Opening shaping plates 91a to 91 having formed therein
If a plurality of sets of 1d are prepared and one of the sets is selectively arranged on the optical path of the illumination light IL, 4
It is also possible to continuously vary the σ value of the opening formed by the aperture shaping plates over a wide range. Furthermore,
Also in this configuration example, since the aperture shaping plates 91a to 91d are configured to be continuously slidable, similar to the first configuration example, for example, the aperture shaping plates 91a to 91d during exposure are performed.
It is also possible to adjust the exposure amount by sliding a to 91d.

[Third Configuration Example of the Aperture Device] FIG. 12 is a perspective view showing a third configuration example of the aperture device according to the embodiment of the present invention, and FIG. 13 is a front view thereof. 12 and 13
The aperture device 60 shown in FIG. 1 includes four aperture shaping plates 100a to 100d as in the second configuration example, but the shapes of the aperture shaping plates 100a to 100d are different. FIG. 14 is a front view showing only the aperture shaping plates 100a to 100d. As shown in FIG. 14, the aperture shaping plate 100a is oblique to the direction indicated by the reference symbol d21 (45 in this example).
The straight portion 101a intersects at a right angle, and a pair of circular arc portions 102a and 103a continuous with both ends of the straight portion 101a. Similarly, the aperture shaping plate 100b includes a straight portion 101b obliquely intersecting (in this example, intersecting at 45 degrees) with a direction denoted by reference numeral d21 in the figure, and a pair of circular arc portions connected to both ends of the straight portion 101b. 102b and 103b.

The aperture shaping plate 100c is indicated by a symbol d in the figure.
The straight portion 101c obliquely intersects (intersects at 45 degrees in this example) with respect to the direction indicated by 21 and a pair of circular arc portions 102c and 103c continuous at both ends of the straight portion 101c. Similarly, the aperture shaping plate 100d includes a straight portion 101d obliquely (intersecting at 45 degrees in this example) with respect to the direction indicated by the reference numeral d21 in the figure, and a pair of circular arc portions connected to both ends of the straight portion 101d. 102d and 103d. Further, the arc-shaped hole portion 104 is formed in the arc-shaped portion 102a of the aperture shaping plate 100a.
a is formed, and the arc-shaped hole 103 is formed in the arc-shaped portion 103a.
5a are formed. Similarly, the aperture shaping plates 100b-
Arc-shaped holes 104b to 104d are respectively formed in the arc-shaped portions 102b to 102d of 100d, and arc-shaped holes 105b to 104d in the arc-shaped portions 103b to 103d.
5d are respectively formed.

The diaphragm device 60 of the third configuration is configured such that the aperture shaping plates 100a to 100d shown in FIG. 14 are formed in a substantially annular shape so that the opposing arc portions of the adjacent aperture shaping plates 100a to 100d partially overlap each other. Arranged and configured. For example,
A portion of the arc portion 102a of the aperture shaping plate 100a and a portion of the arc portion 103c of the aperture shaping plate 100c overlap each other,
Part of the circular arc 103a of the aperture shaping plate 100a and part of the circular arc portion 102d of the aperture shaping plate 100d are arranged so as to overlap each other. With such an arrangement, FIGS.
The opening 106 shown in FIG.

The hole 104a formed in the opening shaping plate 100a and the hole 1 formed in the opening shaping plate 100c are formed.
In FIG. 05c, the cross section in the YZ plane is I-shaped, and the curvature in the longitudinal direction in the XY plane is
a, support member 1 formed to have almost the same curvature as 105c
07a is penetrated, and a support member 107b having the same shape as the support member 107a is disposed through a hole 104b formed in the opening shaping plate 100b and a hole 105d formed in the opening shaping plate 100d. You. Similarly, a support member 107b having the same shape as the support member 107a is arranged to penetrate the hole 104c formed in the opening shaping plate 100c and the hole 105b formed in the opening shaping plate 100b. The support member 107d having the same shape as that of the support member 107a is arranged to penetrate the hole 105a formed in the hole and the hole 104d formed in the opening shaping plate 100d.

These support members 107a to 107d are
Hole portions 104a to 105d, 105a to
The aperture shaping plates 100a to 100d are supported so as to be continuously movable along the circumferential direction of 106d. Therefore, the opening 1 formed by the opening shaping plates 100a to 100d
06, the length in the X-axis direction increases as the length in the Y-axis direction decreases, and conversely, the opening 106 decreases the length in the X-axis direction as the length in the Y-axis direction increases. The plates 100a to 100d are supported. Next, a change in the shape of the opening 106 will be described.

FIG. 15 is a diagram showing how the shape of the opening changes when the opening shaping plates 100a to 100d are slid. FIG. 13 shows a state in which the σ value in the X-axis direction and the σ value in the Y-axis direction of the opening 106 are set to be the same, and this state is a neutral state.

From the state shown in FIG. 13, the support member 107a is moved in the + Y-axis direction as indicated by the arrow in FIG.
07b in the −Y-axis direction or the support member 107
When c is driven in the −X-axis direction and the support member 107d is driven in the + X-axis direction, as shown in FIG.
0a and 100c and the aperture shaping plates 100b and 100d have larger overlapping portions, and the aperture shaping plates 100a and 100d and the aperture shaping plates 100b and 100c have smaller overlapping portions.
Slides along the supporting members 107a to 107d, respectively.

Thus, the linear portion 101a of the aperture shaping plate 100a and the linear portion 1 of the aperture shaping plate 100d
01d becomes smaller (below 90 degrees),
The angle formed by the linear portion 101b of the aperture shaping plate 100b and the linear portion 101c of the aperture shaping plate 100c also becomes smaller (90 degrees or less). As a result, FIG. 13 and FIG.
As can be seen from comparison with (a), the length of the opening 106 in the X-axis direction increases, and the length in the Y-axis direction decreases.

On the other hand, from the state shown in FIG.
As shown by an arrow in (b), when the support member 107a is driven in the −Y axis direction and the support member 107b is driven in the + Y axis direction,
Alternatively, the support member 107c is moved in the + X-axis direction,
When d is driven in the −X-axis direction, as shown in the figure, the aperture shaping plates 100 a and 100 c and the aperture shaping plates 100 b and 1 b are driven.
00d becomes large, and the aperture shaping plates 100a and 100d and the aperture shaping plates 100b and 100c
Each opening shaping plate 100a
To 100d slide along the supporting members 107a to 107d, respectively.

Thus, the straight portion 101a of the aperture shaping plate 100a and the straight portion 1 of the aperture shaping plate 100d
01d becomes larger (90 degrees or more),
The angle formed by the linear portion 101b of the aperture shaping plate 100b and the linear portion 101c of the aperture shaping plate 100c also becomes large (90 degrees or more). As a result, FIG. 13 and FIG.
As can be seen from comparison with (b), the length of the opening 106 in the X-axis direction is reduced, and the length in the Y-axis direction is increased.

As described above, also in the present configuration example, the opening 10 formed by the opening shaping plates 100a to 100d.
6 can be continuously varied. As a result, the σ value in the X-axis direction and the σ value in the Y-axis direction of the opening 106 and their ratio can be continuously varied.

The third configuration example of the diaphragm device 60 has been described above. In this configuration example, similarly to the second configuration example, a rotary table is provided to rotate the aperture shaping plates 100a to 100d in the XY plane. It may be. In the case of this configuration, the support members 107a to 107d are not fixed to the rotary table but are movably arranged along the holes 104a to 104d and 105a to 105d of the aperture shaping plates 100a to 100d. Also in this configuration example, the shape of the opening 106 may be changed manually or automatically.

Further, a plurality of sets of aperture shaping plates 100a to 100d in which arc portions 102a to 102d and 103a to 103d having different curvatures are prepared as in the second configuration example, and any of those sets is prepared. By selectively disposing them on the optical path of the illumination light IL, it is possible to continuously vary the σ value of the opening formed by the four aperture shaping plates over a wide range. Furthermore, also in this configuration example, since the aperture shaping plates 100a to 100d are configured to be continuously slidable, the aperture shaping plates 100a to 100d are, for example, opened during exposure, as in the first and second configuration examples. It is also possible to adjust the exposure amount by sliding the shaping plates 100a to 100d. Further, in each of the first to third configuration examples of the aperture device, the aperture shaping plate is configured to slide. However, the aperture device is not limited to this configuration. A configuration may be adopted in which a plurality of aperture devices having different lengths of the linear portion are exchanged and arranged. Further, a plurality of aperture devices different in at least one of the length of the straight portion and the curvature of the arc portion may be replaced and arranged. Further, in the above-described embodiment, the use of the stop device is premised. However, instead of the stop device, for example, a beam shaping optical system or a diffractive optical element is used, and the illumination light IL on the pupil plane of the illumination optical system is used. (The shape of the secondary light source or the tertiary light source) may be adjusted. Therefore, in the present invention, a diaphragm device for adjusting the shape of the secondary light source or the tertiary light source may be collectively referred to as an “optical device”. Further, in the above-described embodiment, the VH line width difference ΔHV is set to zero or less than a predetermined value, because it is assumed that the vertical wiring and the horizontal wiring have the same line width. When the line width is different between the horizontal wiring and the horizontal wiring, the vertical and horizontal diameters (σ values) of the opening are set so that the line width difference is maintained at the initial value. Further, the center of the light amount of the secondary light source (or the tertiary light source) formed by such an optical device (aperture device) is set so as to substantially coincide with the optical axis of the illumination optical system.

The embodiments described above have been described in order to facilitate understanding of the present invention, but are not described to limit the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, in the above-described embodiment, the case where two optical integrators 30 and 50 are used has been described as an example. However, the present invention is not limited to this, and the present invention is also applicable to an exposure apparatus having only one optical integrator. can do. Also, fly-eye lens, rod type (internal reflection type) as optical integrator
Optical integrators or diffractive optical elements having a diffractive action can be used alone or in combination. However, in any of these cases, the diaphragm device is disposed on the pupil plane of the illumination optical system (in the above-described embodiment, a predetermined plane of the illumination optical system conjugate with the pupil plane of the projection optical system PL) or in the vicinity thereof. . In a rod type (internal reflection type) optical integrator, a light source image formed on a pupil plane of the illumination optical system is formed as a virtual image. In the above-described embodiment, for clarity of description, the optical integrator 30 forms a secondary light source, and the optical integrator 50 forms a tertiary light source. However, in the present invention, the secondary light source and the tertiary light source are distinguished. , A surface light source composed of a plurality of light source images (virtual images) formed on the pupil plane of the illumination optical system may be collectively referred to as a “secondary light source”. Further, the stop device may be disposed between the optical integrator and the mask, or may be disposed between the light source 10 and the optical integrator.

The present invention can be applied to any type of exposure apparatus such as a step-and-repeat type or step-and-stitch type reduction projection type exposure apparatus and a mirror projection aligner. is there. Further, not only an exposure apparatus used for manufacturing a semiconductor element and a liquid crystal display element, but also an exposure apparatus used for manufacturing a plasma display, a thin-film magnetic head, an imaging element (such as a CCD), a micromachine, a DNA chip, and a reticle. Alternatively, the present invention can be applied to an exposure apparatus that transfers a circuit pattern onto a glass substrate, a silicon wafer, or the like in order to manufacture a mask. That is, the present invention is applicable irrespective of the exposure method and application of the exposure apparatus.

The illumination light IL of the exposure apparatus of the present embodiment is
G-line or i-line, or KrF excimer laser, ArF
Excimer lasers, it is assumed to use the light emitted from the F ₂ laser, these limited without X-ray (including EUV light), or may be uses charged particle beams such as ion beams or electron beams. Further, the light source 10 is not limited to a mercury lamp or an excimer laser, but may use a harmonic generator such as a YAG laser or a semiconductor laser. For example, when using an electron beam,
Lanthanum hexaborite (LaB ₆ ) of thermionic emission type,
Tantalum (Ta) can be used. Further, for example, a single-wavelength laser in the infrared or visible region oscillated from a DFB semiconductor laser or a fiber laser is amplified by a fiber amplifier doped with erbium (or both erbium and ytterbium), and further, a nonlinear optical crystal. May be used to convert the wavelength to ultraviolet light. In addition, as a single wavelength oscillation laser,
A doped fiber laser is used.

The projection optical system may be not only a reduction system but also an equal magnification system or an enlargement system. Further, the projection optical system may be not only a refraction system but also a catadioptric system or a reflection system. Further, the illumination optical system for irradiating the mask M with EUV light as the illumination light IL is composed of only a plurality of reflection optical elements, but the aperture device may be either a reflection type or a transmission type.

The above-described exposure apparatus (FIG. 1) according to the embodiment of the present invention can precisely control the position of the wafer W at high speed, and can perform exposure with high exposure accuracy while improving throughput. , Light source 10, beam shaping optical system 2
0, optical integrator 30, relay optical system 4
0, optical integrator 50, and aperture device 6
Optical system, mask stage MS including zero
After the components shown in FIG. 1 such as a mask alignment system including a wafer stage WS, a wafer alignment system including a wafer stage WS, and a projection optical system PL are electrically, mechanically or optically connected and assembled, comprehensive adjustment is performed. (Electrical adjustment, operation check, etc.)
It is manufactured by doing. In addition, the manufacture of the exposure apparatus
It is desirable to perform in a clean room where the temperature and cleanliness are controlled.

To produce a device (semiconductor chip such as IC or LSI, liquid crystal panel, CCD, thin film magnetic head, micromachine, etc.) using the exposure apparatus according to the embodiment of the present invention, first, in the design step, (For example, circuit design of a semiconductor device) and a pattern design for realizing the function. Subsequently, in a mask manufacturing step, a mask on which the designed circuit pattern is formed is manufactured. On the other hand, in a wafer manufacturing step, a wafer is manufactured using a material such as silicon.

Next, in the wafer process step,
Using the mask and wafer prepared in the above steps, an actual circuit or the like is formed on the wafer by lithography technology. Next, in an assembling step, chips are formed using the wafer processed in the wafer process step. This assembling step includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). Finally, in an inspection step, inspections such as an operation confirmation test and a durability test of the device manufactured in the assembly step are performed. After these steps, the device is completed and shipped.

[0093]

As described above, according to the present invention,
A diaphragm device for changing the ratio of the length of the opening in the first direction and the length in the second direction orthogonal to each other of the opening for shaping the cross-sectional shape of the illumination light is provided on the pupil plane of the illumination optical system. Since the ratio between the length of the cross section and the length of the cross section of the illumination light in the second direction can be varied to adjust the amount of exposure in the first direction and the amount of exposure in the second direction, the first direction and the second direction orthogonal to each other can be adjusted. There is an effect that the line widths of the wirings formed in two directions can be formed substantially the same under various circumstances.

[Brief description of the drawings]

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

FIG. 2 is a front view of the optical integrator of FIG.

FIG. 3 is a diagram for explaining a configuration of an opening included in a diaphragm device provided in the exposure apparatus according to the embodiment of the present invention.

FIG. 4 is a perspective view showing a first configuration example of a diaphragm device according to the embodiment of the present invention.

FIG. 5 is a front view showing a first configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 6 is a front view of an aperture shaping plate in the first configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 7 is a diagram showing a state in which the shape of the opening changes when the aperture shaping plate is slid or rotated in the XY plane in the first configuration example of the aperture device according to the embodiment of the present invention. .

FIG. 8 is a perspective view showing a second configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 9 is a front view showing a second configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 10 is a front view of an aperture shaping plate in a second configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 11 is a diagram showing a state where the shape of the opening changes when the aperture shaping plate is slid in the second configuration example of the aperture device according to the embodiment of the present invention.

FIG. 12 is a perspective view showing a third configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 13 is a front view showing a third configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 14 is a front view of an aperture shaping plate in a third configuration example of the diaphragm device according to the embodiment of the present invention.

FIG. 15 is a diagram showing a state where the shape of the opening changes when the aperture shaping plate is slid in the third configuration example of the aperture device according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 light source 20 beam shaping optical system 30 optical integrator 40 relay optical system 50 optical integrator 60 aperture device 61, 90, 97, 106 aperture 80a, 80b aperture shaping plate (diaphragm member) 81 rotation Tables 83a, 83b, 84a, 84b: Linear portions 85a, 85b: Arc portions 91a to 91d: Opening shaping plates (aperture members) 92a to 92d, 93a to 93d: Linear portions 94a to 94d: Arc portions 100a to 100d: Opening shapes Plates (aperture members) 101a to 101d: linear portions 102a to 102d, 103a to 103d: arc portions d1, d11, d21: first direction d12, d22: second direction IL: illumination light M: mask W: wafer (substrate)

Claims (13)

[Claims] 1. An exposure apparatus that illuminates a mask with illumination light emitted from a light source and sent through an illumination optical system, and projects an image of a pattern formed on the mask onto a substrate, wherein a cross-sectional shape of the illumination light is provided. A diaphragm device having an opening for shaping the aperture, and changing a ratio of a length of the opening in a first direction to a length of a second direction orthogonal to the first direction. An exposure apparatus, comprising: 2. The diaphragm device according to claim 1, further comprising: a pair of aperture shaping plates having a pair of straight portions and a circular arc portion respectively connected to the straight portions and arranged along the first direction. The aperture shaping plate is symmetrically arranged so that a part of the opposed linear portions of the aperture shaping plate overlap with each other, and is supported so as to be slidable in a direction substantially parallel to the first direction. The exposure apparatus according to claim 1, wherein 3. The aperture device according to claim 1, wherein the aperture device comprises four aperture shaping plates each having a linear portion along the first direction, a linear portion along the second direction, and an arc portion continuous with the linear portion. The plates are arranged in a substantially annular shape so that a part of the opposed linear portions of the adjacent aperture shaping plates overlap with each other, and are slidable in directions substantially parallel to the first direction and the second direction, respectively. The exposure apparatus according to claim 1, wherein the exposure apparatus is supported by: 4. The aperture device includes four opening shaping plates each having a straight portion obliquely oblique to the first direction and a pair of circular arc portions at both ends of the straight portion. A portion of the circular arc portion of the adjacent opening shaping plate is arranged in a substantially annular shape so as to overlap with each other, and the length of the opening in the second direction decreases as the length of the opening in the first direction decreases. 2. The exposure apparatus according to claim 1, wherein the length of the opening in the first direction increases and the length of the opening in the second direction decreases. 5. A rotating table for rotating the aperture shaping plate in a cross section of the illumination light in a state where the shape of the opening is determined by the aperture shaping plate. 5. The exposure apparatus according to 3 or 4. 6. The aperture device, wherein the aperture device has a plurality of aperture members each having an opening shape having a different ratio between the length in the first direction and the length in the second direction, and any one of the plurality of aperture members. 2. The exposure apparatus according to claim 1, further comprising: an exchange device for selectively arranging one on an optical path of the illumination light. 7. A device manufacturing method, comprising a step of transferring a device pattern onto a workpiece using the exposure apparatus according to claim 1. Description: 8. An illumination device having an illumination optical system for uniforming the illuminance distribution of incident illumination light and shaping a cross-sectional shape, comprising: an opening for shaping a cross-sectional shape of the illumination light. An illumination device, wherein a diaphragm device for changing a ratio between a length of the opening in a first direction and a length in a second direction orthogonal to the first direction is provided on a pupil plane of the illumination optical system. 9. An exposure apparatus having an illumination optical system for irradiating illumination light from a light source onto a mask, and transferring a pattern formed on the mask onto a substrate, wherein the patterns are respectively arranged in first and second directions. When including a linear element extending, the linear element has a pair of linear portions defined along one of the first and second directions on a pupil plane of the illumination optical system and symmetric with respect to an optical axis of the illumination optical system. An exposure apparatus comprising an optical device for forming a secondary light source. 10. The optical apparatus according to claim 1, wherein the first and the second direction linear elements have a line width difference of a transferred image substantially maintained at a predetermined value. The exposure apparatus according to claim 9, wherein a difference in size of the secondary light source in a second direction is adjusted. 11. The exposure apparatus according to claim 9, wherein the optical device has a variable length of the pair of linear portions. 12. The exposure apparatus according to claim 9, wherein the optical device forms a secondary light source in which the pair of linear portions are connected by an arc portion. 13. The exposure apparatus according to claim 9, wherein the secondary light source has a light amount center of gravity substantially coincident with an optical axis of the illumination optical system.