JP2006228794A - Illuminating optical device, exposure device, and method of exposure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illuminating optical device which can correct illuminance unevenness good and quickly even if an illumination distribution in the surface to be illuminated is changed in an aging manner. <P>SOLUTION: The illumination optical device illuminates the surface to be illuminated (M, P) by light from a light source (1). The light source section has a plurality of unit areas, a plurality of light emitting regions formed in each of the plurality of the these unit areas, and a controller for controlling light emitting outputs of the plurality of the light emitting regions. Light guiding optical systems (2, 4) for leading luminous fluxes to the lighting region on the surface to be illuminated in a superposition manner after the luminous fluxes are once condensed from each of a plurality of the unit areas are provided in the optical path between the light source and the surface to be illuminated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an illumination optical apparatus, an exposure apparatus, and an exposure method. More particularly, the present invention relates to an illumination optical apparatus suitable for an exposure apparatus used for manufacturing a microdevice such as a semiconductor element or a liquid crystal display element in a lithography process.

  For example, a liquid crystal display element as a micro device is manufactured by patterning a transparent thin film electrode into a desired shape on a glass substrate (plate) by a photolithography technique to form a switching element such as a TFT and an electrode wiring. In the manufacturing process of a liquid crystal display element using this photolithography technique, an exposure apparatus that projects and exposes an original pattern formed on a mask onto a plate coated with a photosensitive agent such as a photoresist via a projection optical system. Is used.

  Conventionally, in this type of exposure apparatus, after the relative alignment between the mask and the plate is performed, the pattern on the mask is collectively transferred to one exposure area (shot area) on the plate to transfer the pattern. Later, a system in which the plate is moved stepwise to perform transfer to other exposure areas in sequence, that is, a step-and-repeat system has been frequently used. In recent years, a liquid crystal display element has been required to have a large area, and accordingly, an exposure area used in an photolithography process is desired to be expanded. In order to enlarge the exposure area in the exposure apparatus, for example, there is a method of increasing the size of the projection optical system. However, it is expensive to design and manufacture a large projection optical system in which residual aberrations are reduced as much as possible. .

  Therefore, a step-and-scan method has been proposed in order to expand the exposure area while avoiding an increase in the size of the projection optical system. In a step-and-scan exposure apparatus, a mask is irradiated with slit-shaped illumination light having a length in the longitudinal direction substantially the same as the effective diameter (diameter) on the object side (mask side) of the projection optical system. Then, with the slit-shaped light passing through the mask forming a partial image of the mask pattern on the plate via the projection optical system, the mask and the plate are moved relative to the projection optical system. Then, the mask pattern is subjected to scanning exposure (scan exposure) on one shot area on the plate. In this way, scanning exposure to each shot area is sequentially repeated while moving the plate stepwise (see, for example, Patent Document 1).

Japanese Patent No. 3482976

  In the conventional exposure apparatus, as the exposure area expands as described above, it becomes a problem to ensure illuminance uniformity in the exposure area. Specifically, illuminance unevenness often occurs such that the illuminance at the periphery is lower than the illuminance at the center of the exposure area. Thus, for example, the required illuminance uniformity in the exposure region is realized by intentionally generating the required distortion by the main condenser lens. However, the illumination distribution may change over time beyond the adjustment range of the main condenser lens due to the clouding or solarization of the lens.

  Conventionally, when the illumination distribution changes over time beyond the adjustment range, a method of exchanging with another main condenser lens that generates a different amount of distortion has been used. However, in the conventional technique for exchanging the main condenser lens, there is a disadvantage that the manufacturing and the exchange directly lead to a relatively large cost increase, and the time loss due to the stoppage of the apparatus for the exchange work is large.

  The present invention has been made in view of the above-described problems, and provides an illumination optical device capable of correcting illuminance unevenness satisfactorily and quickly even if the illuminance distribution on the irradiated surface changes with time. For the purpose. In addition, the present invention uses an illumination optical device that can correct illuminance unevenness satisfactorily and quickly even when the illuminance distribution changes over time, and has high accuracy and high throughput under desired illumination conditions. An object of the present invention is to provide an exposure apparatus and an exposure method capable of performing exposure.

In order to solve the above problems, in the first embodiment of the present invention, in the illumination optical device that illuminates the illuminated surface with light from the light source unit,
The light source unit includes a plurality of unit areas, a plurality of light emitting regions provided in each of the plurality of unit areas, and a control unit for controlling light emission outputs of the plurality of light emitting regions,
In the optical path between the light source unit and the illuminated surface, the light flux from each of the plurality of unit areas is once condensed and then superimposed on the illumination area on the illuminated surface. Provided is an illumination optical device including a light guide optical system.

In the second embodiment of the present invention, in the illumination optical device that illuminates the irradiated surface with light from the light source unit,
The light source unit includes a plurality of unit areas, and a control unit for controlling the luminance distribution in the plurality of unit areas,
Arranged in an optical path between the light source unit and the illuminated surface, once the light flux from each of the plurality of unit areas is once condensed, and then superimposed on the illumination area on the illuminated surface. There is provided an illumination optical device comprising a light guide optical system.

  According to a third aspect of the present invention, there is provided an exposure apparatus comprising the illumination optical apparatus according to the first or second aspect, and exposing a pattern of a mask illuminated by the illumination optical apparatus onto a photosensitive substrate. To do.

  According to a fourth aspect of the present invention, the method includes an illumination step of illuminating a mask using the illumination optical apparatus of the first or second aspect, and an exposure step of exposing the pattern of the mask onto a photosensitive substrate. An exposure method is provided.

  In the illumination optical device of the present invention, even if the illuminance distribution on the irradiated surface changes with time due to, for example, the cloud of the lens or solarization, the light emitted from the plurality of light emitting regions provided in each of the plurality of unit areas By controlling the output, illuminance unevenness can be corrected satisfactorily and quickly. In the exposure apparatus and exposure method of the present invention, since the illumination optical device that can correct illuminance unevenness satisfactorily and quickly even when the illuminance distribution changes with time, the desired illumination condition can be obtained. Thus, exposure with high accuracy and high throughput can be performed, and as a result, a device such as a liquid crystal display element can be manufactured with high throughput and high accuracy.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a drawing schematically showing a configuration of an exposure apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the internal configuration of the light source unit of FIG. In FIG. 1, the Z-axis is along the normal direction of the surface of a plate (resist-coated glass substrate) P, which is a photosensitive substrate, and the Y-axis is in the direction parallel to the paper surface of FIG. The X axis is set in the direction perpendicular to the paper surface of FIG.

  The exposure apparatus shown in FIG. 1 includes a light source unit 1 for supplying exposure light. As illustrated in FIG. 2, the light source unit 1 includes a plurality of unit areas 11 to 14 (only four are illustrated in FIG. 2) that are densely arranged vertically and horizontally along the XY plane. A plurality of solid light source elements 15 are provided in each unit area (11 to 14). As the solid light source element 15, for example, an LED (light emitting diode) or a laser diode can be used. Further, the light source unit 1 controls the light emission output (luminance, brightness) of the light emitting region (LED or laser diode light emitting unit) 15a of the solid light source element 15 for each unit area, and thus a plurality of unit areas (11 to 14). The control unit 16 is provided for controlling the luminance distributions in parentheses).

  That is, the control unit 16 changes the light emission output of the plurality of light emitting regions 15a for each unit area by uniformly raising and lowering the power applied to the plurality of solid light source elements 15 for each unit area, for example. Hereinafter, in order to simplify the description and the drawings, the solid light source element 15 and the light emitting region 15a thereof are indicated by the same rectangular hatched portion in FIG. 2 and related drawings. For the sake of clarity, FIG. 2 shows only four unit areas (11 to 14) symmetrically arranged with respect to the X axis and the Y axis about the optical axis AX. The number of unit areas and the number of field lenses arranged corresponding to each unit area are displayed smaller than actual.

  In the light source unit 1, all the unit areas including the four unit areas (11 to 14) have the same shape, that is, an elongated rectangular shape along the X direction. And in the 1st unit area 11 and the 2nd unit area 12, the light emission area | region 15a of each solid light source element 15 is arrange | positioned according to a mutually complementary pattern. That is, when the first unit area 11 and the second unit area 12 are overlapped, the plurality of light emitting regions 15a are arranged vertically and horizontally and almost densely in the rectangular effective region of the unit area. Yes.

  Similarly, also in the 3rd unit area 13 and the 4th unit area 14, the light emission area | region 15a of each solid light source element 15 is arrange | positioned according to a mutually complementary pattern. Other unit areas not shown include, for example, a pair of unit areas in which the light emitting areas 15a are arranged according to a complementary pattern, unit areas in which the light emitting areas 15a are arranged in parallel over the entire effective area, and the like. It is out.

  In the present embodiment, the light beam from the light source unit 1 enters the field lens array 2. The field lens array 2 is composed of a plurality of field lenses 2 a and 2 b that are densely arranged vertically and horizontally so as to correspond to the plurality of unit areas (11 to 14) of the light source unit 1. Here, the plurality of field lenses 2a are formed by a plurality of convex lenses provided for each unit area of the light source unit 1, and the plurality of field lenses 2b are a plurality of plano-convex lenses provided in a one-to-one correspondence with the plurality of field lenses 2a. It is formed with. Therefore, the light flux from each unit area (11-14) of the light source unit 1, that is, the light flux from the plurality of light emitting areas 15a provided in the effective area of each unit area (11-14), corresponds to the corresponding field lens 2a. , 2b, the light is condensed on a predetermined surface (not shown). Thus, the plurality of field lenses 2a and 2b constitute a plurality of field optical elements for condensing the light beams from the plurality of unit areas (11 to 14), respectively.

  Here, the position in the vicinity of the exit surface of the field lens array 2 is regarded as a secondary light source (substantial surface light source). The light beam from the secondary light source is incident on the aperture stop 3 disposed at or near the formation position of the secondary light source. The aperture stop 3 is disposed at a position substantially optically conjugate with the entrance pupil plane of the projection optical system PL, and has a variable aperture for defining a range that contributes to illumination of the secondary light source. The aperture stop 3 changes the aperture diameter of the variable aperture, thereby determining the illumination σ value (the ratio of the aperture of the secondary light source image on the pupil plane to the aperture diameter of the pupil plane of the projection optical system). ) To the desired value.

  Light from the secondary light source through the aperture stop 3 enters the condenser optical system (main condenser lens) 4. The condenser optical system 4 is positioned so that its front focal plane substantially coincides with the secondary light source formation surface. Therefore, the light from the secondary light source receives the condensing action of the condenser optical system 4 and illuminates the mask M on which the predetermined pattern is formed in a superimposed manner. Thus, a rectangular illumination area similar to the effective area of each unit area (11 to 14) of the light source unit 1 is formed on the mask M as the irradiated surface. That is, the mask M and the plurality of light emitting regions 15 a are optically substantially conjugate with respect to the field lens array 2 and the condenser optical system 4.

  Note that a mask blind and a blind imaging optical system as a field stop for defining the shape of the illumination area formed on the mask M can be arranged in the optical path between the condenser optical system 4 and the mask M. . As described above, the condenser optical system 4 has a function of superimposing the light flux from each of the plurality of field lenses 2 a and 2 b on the illumination area of the mask M. The field lens array 2 and the condenser optical system 4 are arranged in an optical path between the light source unit 1 and the mask M as the irradiated surface, and light beams from each of the plurality of unit areas (11 to 14). Are once condensed, and then a light guide optical system for superposing and guiding the light to the illumination area on the mask M is configured.

  The mask M is held parallel to the XY plane (that is, the horizontal plane) on the mask stage MS via a mask holder (not shown). The mask stage MS can be moved two-dimensionally along the mask surface (that is, the XY plane) by the action of a mask stage drive system (not shown), and its position coordinates are measured by a mask interferometer (not shown). In addition, the position is controlled. The light beam transmitted through the pattern of the mask M forms a rectangular mask pattern image on the plate P through the projection optical system PL.

  On the pupil plane of the projection optical system PL or in the vicinity thereof, an aperture stop AS for defining the numerical aperture is disposed. The plate P is held parallel to the XY plane on the plate stage PS via a plate holder (not shown). The plate stage PS can be moved two-dimensionally along the plate surface (ie, the XY plane) by the action of a plate stage drive system (not shown), and its position coordinates are measured by a plate interferometer (not shown) and The position is controlled.

  Thus, by performing projection exposure in a stationary state in which the mask M and the plate P are aligned with respect to the projection optical system PL, the pattern of the mask M is collectively exposed to the shot area (exposure area) of the plate P. In this case, batch exposure is sequentially performed on each shot area of the plate P while stepping the plate P along the XY plane according to the step-and-repeat method.

  Alternatively, by performing projection exposure while moving the mask M and the plate P along the scanning direction (for example, the Y direction) with respect to the projection optical system PL, the pattern of the mask M is scanned and exposed on the shot area of the plate P. The In the scanning exposure, the size of the rectangular mask pattern image formed in a stationary state in one shot area on the plate P along the scanning orthogonal direction (direction orthogonal to the scanning direction, for example, the X direction) A rectangular pattern defined by a dimension corresponding to the moving distance along the scanning direction is formed. In this case, scanning exposure is sequentially performed on each shot area of the plate P while stepping the plate P along the XY plane according to the step-and-scan method.

  In the present embodiment, for example, by applying the same power to the solid light source elements 15 in all unit areas of the light source unit 1, in the rectangular illumination region on the mask M, the rectangular exposure region on the plate P (by extension) A substantially uniform illuminance distribution can be obtained in the still exposure region). However, as described above, two-dimensional convex illuminance unevenness (see FIG. 3A) is initially generated such that the illuminance at the peripheral portion is lower than the illuminance at the center of the exposure region. There is. In this case, for example, the power applied to all the solid state light source elements 15 in the fourth unit area 14 is uniformly increased, or the power applied to all the solid state light source elements 15 in the third unit area 13 is uniformly decreased. As a result, the illuminance at the center of the exposure area can be relatively lowered, and as a result, the convex illuminance unevenness as shown in FIG.

  Also, in this embodiment, the illumination distribution that has been initially adjusted almost uniformly changes over time due to, for example, the lens cloud or solarization, and the illuminance at the peripheral portion with respect to the illuminance at the central portion of the exposure area Two-dimensionally concave illuminance unevenness (see FIG. 3B) may occur. In this case, for example, the power applied to all the solid state light source elements 15 in the fourth unit area 14 is uniformly decreased, or the power applied to all the solid state light source elements 15 in the third unit area 13 is uniformly increased. By doing so, it is possible to relatively reduce the illuminance at the periphery of the exposure region, and thereby correct the concave illuminance unevenness as shown in FIG.

  Similarly, for example, the power applied to all the solid state light source elements 15 in the first unit area 11 is uniformly lowered or raised, or the power applied to all the solid state light source elements 15 in the second unit area 12 is uniform. By lowering or raising, it is possible to correct uneven illumination unevenness along the X direction as indicated by a solid line or a broken line in FIG. Incidentally, in the present embodiment, when scanning exposure is performed while moving the mask M and the plate P in the Y direction with respect to the projection optical system PL, the scanning area is in the scanning direction due to the averaging effect of the scanning exposure. Even if a certain amount of illuminance unevenness remains in the Y direction, it does not cause a big problem. The illuminance unevenness that should be corrected well in the exposure region on the plate P is the illuminance unevenness in the X direction, which is the direction orthogonal to the scanning.

  As described above, in the illumination optical device according to the present embodiment, even if the illuminance distribution on the irradiated surface (mask M and plate P) changes with time due to, for example, clouding or solarization of the lens, the light emitting region 15a. Is generally provided in each of the plurality of unit areas (11-14) by adjusting the power applied to the pair of unit areas (11, 12; 13, 14) arranged according to the complementary pattern. By controlling the light emission output of the plurality of light emitting regions 15a, it is possible to correct illuminance unevenness satisfactorily and quickly. Further, in the exposure apparatus of the present embodiment, an illumination optical apparatus that can correct illuminance unevenness satisfactorily and quickly even when the illuminance distribution changes with time is used. Projection exposure with high accuracy and high throughput can be performed.

  In the above-described embodiment, convex or concave illuminance unevenness is corrected by adjusting the power applied to the third unit area 13 and the fourth unit area 14. However, in addition to the third unit area 13 and the fourth unit area 14, or instead of the third unit area 13 and the fourth unit area 14, the light emitting region 15a is as shown in FIGS. 4 (a) and 4 (b). It is also possible to correct convex or concave illuminance unevenness by adjusting the power applied to a pair of unit areas arranged according to a complementary pattern.

  In general, various embodiments are possible with respect to the number of a pair of unit areas arranged according to mutually complementary patterns, the arrangement thereof, the form of the arrangement pattern of the light emitting regions, and the like. What is important in the present embodiment is that the light source unit 1 includes at least one pair of unit areas arranged according to mutually complementary patterns, and the light emitting region 15a extends over the entire effective region. It is common to have one or more unit areas arranged in parallel.

  In the above-described embodiment, the uneven illuminance uneven along the X direction is corrected by adjusting the power applied to the first unit area 11 and the second unit area 12. However, when performing batch exposure in a stationary state in which the mask M and the plate P are aligned with respect to the projection optical system PL, the light emitting region 15a is shown in FIGS. 5A and 5B as necessary. By adjusting the power applied to a pair of unit areas arranged according to such a complementary pattern, it is possible to correct the uneven illumination unevenness along the Y direction.

  In the above-described embodiment, since the mask M and the plurality of light emitting regions 15a in the unit area are optically substantially conjugate, when the plurality of light emitting regions 15a are discretely arranged, the unit The uneven luminance distribution in the area may adversely affect the illuminance distribution formed in the illumination area on the mask M (and thus in the exposure area on the plate P). In this case, as shown in FIG. 6, by disposing the diffusion plate 5 in the optical path between the light source unit 1 and the field lens array 2, the influence of the non-uniform luminance distribution in the unit area is suppressed and substantially uniform. Illuminance distribution can be obtained. Here, unlike the field lens array 2 of FIG. 1, the field lens array 2 of FIG. 6 includes a plurality of biconvex field lenses 2c. Note that the field lens array 2 constituted by the plurality of biconvex field lenses 2c can also be applied as the field lens array 2 of FIG. Further, for example, the field lens array 2 is defocused on the light emitting surface of the light source unit 1 (the surface on which the plurality of light emitting regions 15a are arranged), or the mask M is defocused on the condenser optical system 4. As a result, it is possible to obtain an almost uniform illuminance distribution while suppressing the influence of the nonuniform luminance distribution in the unit area.

  In the above-described embodiment, the field lens array 2 is provided in the optical path between the light source unit 1 and the condenser optical system 4. For example, by using an LED with a field lens as the solid light source element 15, the field lens array 2 is used. The arrangement of the lens array 2 can be omitted.

  In the above-described embodiment, the field lenses 2a and 2b are used as visual field optical elements for collecting the light beams from the unit areas (11 to 14). However, the present invention is not limited to this, and a field mirror, DOE, or the like can be used as the field optical element instead of the field lens.

  In the above-described embodiment, an example in which the light source unit 1 has four or more rectangular unit areas arranged densely in the vertical and horizontal directions is generally described. However, in general, the number of unit areas and the shape of the unit areas are described. Various embodiments of the arrangement and the like are possible. This also applies to a modification of the light source unit 1 described later.

  FIG. 7 is a diagram schematically illustrating a main configuration of the light source unit according to the first modification of the present embodiment. In the light source unit of the first modification, for example, a plurality of rectangular unit areas in which a plurality of light emitting regions are arranged in parallel over the entire rectangular effective region are arranged densely in the vertical and horizontal directions. However, FIG. 7 shows only the unit area 17 having a characteristic configuration among the plurality of unit areas. Specifically, in at least one unit area 17 among the plurality of unit areas, the light emission output of the light emitting region 15a of the solid light source element 15 is controlled individually or in groups by the control unit 16a, and in other unit areas (not shown) The light emission output of the light emitting region 15a of the solid light source element 15 is controlled for each unit area by the control unit 16a.

  In the light source unit of the first modification, for example, by applying the same power to the solid state light source elements 15 in all unit areas, in the rectangular illumination region on the mask M, and in the rectangular exposure region on the plate P, for example. An almost uniform illuminance distribution can be obtained. When two-dimensionally convex illuminance unevenness is initially generated such that the illuminance at the peripheral portion is lower than the illuminance at the central portion of the exposure area, By increasing the power applied to the solid light source element 15 or decreasing the power applied to the plurality of solid light source elements 15 arranged in the central part of the unit area 17, the relative illuminance at the central part of the exposure region is changed. Therefore, the uneven illumination unevenness can be corrected satisfactorily and promptly.

  In addition, the illumination distribution that has been initially adjusted almost uniformly changes over time due to, for example, the lens's cloud and solarization, and the illuminance at the periphery is higher than the illuminance at the center of the exposure area. When the dimensional uneven illumination unevenness occurs, for example, the power applied to the plurality of solid state light source elements 15 arranged in the peripheral part of the unit area 17 is lowered, or the plurality of parts arranged in the central part of the unit area 17 are reduced. By increasing the electric power applied to the solid state light source element 15, the illuminance at the periphery of the exposure region can be relatively decreased, and the concave illuminance unevenness can be corrected favorably and promptly. As described above, in the first modification, by controlling the light emission output of the light emitting region 15a of the solid state light source element 15 individually or group by group in at least one unit area 17, even if the illuminance distribution changes with time, the illuminance Unevenness can be corrected satisfactorily and quickly.

  FIG. 8 is a diagram schematically illustrating a main configuration of a light source unit according to a second modification of the present embodiment. In the light source unit of the second modification, a plurality of rectangular unit areas in which a plurality of light emitting regions are arranged in parallel over the entire cross-shaped effective region are arranged densely in the vertical and horizontal directions. However, FIG. 8 shows only the unit area 18 having a characteristic configuration among the plurality of unit areas. Specifically, in at least one unit area 18 out of the plurality of unit areas, the first partial effective area elongated in the lateral direction in the cross-shaped effective area (see FIG. a) the light emission output of the light emitting region 15a of the solid state light source elements 15 arranged in parallel in the rectangular region formed as a whole by a plurality of rectangular shaded portions in a), and the rectangular second portion effective in the longitudinal direction. The light emission output of the light emitting region 15a of the solid state light source elements 15 arranged in parallel in the region (rectangular region formed by a plurality of hatched portions as a whole in FIG. 8B) is controlled individually or in groups. The

  On the other hand, in other unit areas (not shown) other than the unit area 18, the light output of the light emitting region 15 a of the solid light source element 15 arranged in parallel in the first partial effective region and the second portion are obtained by the action of the control unit 16 b. The light emission output of the light emitting area 15a of the solid state light source elements 15 arranged in parallel in the effective area is controlled for each partial effective area. Therefore, in the second modification, for example, in all unit areas including the unit area 18, the power is applied only to the solid light source elements 15 arranged in parallel in the first partial effective region, so that the X direction on the mask M is applied. An elongated rectangular illumination area can be formed on the plate P, and an elongated rectangular exposure area can be formed on the plate P in the X direction.

  Further, by applying electric power only to the solid state light source elements 15 arranged in parallel in the second partial effective area, a rectangular illumination area elongated in the Y direction on the mask M is formed, and as a result, the Y direction on the plate P. An elongated rectangular exposure region can be formed. In other words, by switching the power supply between the first partial effective area and the second partial effective area, the shape of the illumination area on the mask M can be changed on the plate P without substantially losing the amount of light. The shape of the exposure area can be switched. Further, in the second modification, by controlling the light emission output of the light emitting region 15a of the solid light source element 15 individually or in groups in the first partial effective region or the second partial effective region of at least one unit area 18, Even if the illuminance distribution changes over time, the illuminance unevenness can be corrected satisfactorily and quickly.

  FIG. 9 is a diagram schematically showing the internal configuration of the light source unit according to the third modification of the present embodiment. As shown in FIG. 9, the light source section of the third modification has a plurality of light emitting regions 15a (4 × 7 = 28 in the example shown in FIG. 9) arranged in parallel over the entire rectangular effective region. A plurality of rectangular unit areas 19 are arranged vertically and horizontally and densely (4 × 4 = 16 in FIG. 9 exemplarily). In each unit area 19, the light emission output of the light emitting region 15a of the solid light source elements 15 arranged in parallel in the effective region is controlled for each unit area by the action of the control unit 16c.

  Further, in at least one unit area 19a (not shown) of the plurality of unit areas 19, the light emission output of the light emitting regions 15a of the solid light source elements 15 arranged in parallel in the effective region is individually generated by the action of the control unit 16c. Or controlled by group. Accordingly, in the third modification, for example, solids in 12 unit areas arranged in the peripheral part are supplied without supplying power to the solid light source elements 15 in the four unit areas arranged in the central part of the light source part. By supplying power to the light source element 15, it is possible to form a secondary light source having a centrally shielded form in the vicinity of the exit surface of the field lens array 2.

  In general, by switching the power supply to the plurality of unit areas 19 for each unit area, various forms of secondary light sources can be formed in the vicinity of the exit surface of the field lens array 2, and thus various forms Modified illumination can be performed. In the third modification, the illuminance distribution changes over time by controlling the light emission output of the light emitting region 15a of the solid light source element 15 individually or group by group in the effective region of at least one unit area 19a. Also, it is possible to correct illuminance unevenness satisfactorily and quickly.

  The exposure apparatus according to the present embodiment is obtained by electrically, mechanically, or optically coupling the optical members and the stages in the embodiment shown in FIG. 1 so as to achieve the functions described above. Can be assembled. Next, in the exposure apparatus shown in FIG. 1, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG.

  In FIG. 10, in the pattern forming process 401, a so-called photolithography process is performed in which the pattern of the mask (reticle) is transferred and exposed to a photosensitive substrate (such as a glass substrate coated with a resist) using the exposure apparatus of the present embodiment. Is done. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step 402.

  Next, in the color filter forming step 402, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three of R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning line direction. Then, after the color filter forming step 402, a cell assembly step 403 is executed.

  In the cell assembly step 403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step 401, the color filter obtained in the color filter formation step 402, and the like. In the cell assembly step 403, for example, liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern formation step 401 and the color filter obtained in the color filter formation step 402, and a liquid crystal panel (liquid crystal cell) is obtained. ).

  Thereafter, in a module assembling step 404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, a liquid crystal display element having an extremely fine circuit pattern can be obtained with high throughput.

  In addition, a semiconductor device as a micro device can be obtained by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the exposure apparatus according to the embodiment shown in FIG. Hereinafter, an example of a method for obtaining a semiconductor device as a micro device will be described with reference to the flowchart of FIG.

  First, in step 301 of FIG. 11, a metal film is deposited on one lot of wafers. In the next step 302, a photoresist is applied on the metal film on the one lot of wafers. Thereafter, in step 303, using the exposure apparatus shown in FIG. 1, the image of the pattern on the mask (reticle) is sequentially exposed and transferred to each shot area on the wafer of one lot via the projection optical system PL. The

  Thereafter, in step 304, the photoresist on the one lot of wafers is developed, and in step 305, the resist pattern is etched on the one lot of wafers to form a pattern on the mask. Corresponding circuit patterns are formed in each shot area on each wafer. Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the semiconductor device manufacturing method described above, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput.

  In the above-described embodiment, the present invention is applied to the illumination optical apparatus of the exposure apparatus. However, the present invention is not limited to this, and a general illumination optical apparatus that illuminates an irradiated surface other than the mask. However, the present invention can be similarly applied.

It is a figure which shows schematically the structure of the exposure apparatus concerning embodiment of this invention. It is a figure which shows schematically the internal structure of the light source part of FIG. It is a figure which shows the form of the illumination intensity nonuniformity correctable in this embodiment exemplarily. It is a figure which shows the form of a pair of unit area arrange | positioned according to a complementary pattern in order to correct | amend a convex-shaped or concave illuminance nonuniformity. It is a figure which shows the form of a pair of unit area arrange | positioned according to a complementary pattern in order to correct | amend inclination-shaped illumination unevenness. It is a figure which shows the example which has arrange | positioned the diffuser plate in the optical path between a light source part and a field lens array in this embodiment. It is a figure which shows schematically the principal part structure of the light source part concerning the 1st modification of this embodiment. It is a figure which shows roughly the principal part structure of the light source part concerning the 2nd modification of this embodiment. It is a figure which shows schematically the internal structure of the light source part concerning the 3rd modification of this embodiment. It is a figure which shows the flowchart about an example of the method at the time of obtaining the liquid crystal display element as a microdevice. It is a figure which shows the flowchart about an example of the method at the time of obtaining the semiconductor device as a microdevice.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source part 2 Field lens array 3 Aperture stop 4 Condenser optical system 5 Diffusion plates 11-14, 17-19 Unit area 15 Solid light source element 15a Light emission area 16, 16a-16c of solid light source element Control part M Mask MS Mask stage PL Projection optical system AS Aperture stop P Plate PS Plate stage

Claims (13)

In the illumination optical device that illuminates the irradiated surface with light from the light source unit,
The light source unit includes a plurality of unit areas, a plurality of light emitting regions provided in each of the plurality of unit areas, and a control unit for controlling light emission outputs of the plurality of light emitting regions,
In the optical path between the light source unit and the illuminated surface, the light flux from each of the plurality of unit areas is once condensed and then superimposed on the illumination area on the illuminated surface. An illumination optical apparatus comprising a light guide optical system. The light guide optical system includes a plurality of field optical elements for condensing light beams from the plurality of unit areas, and a light beam from each of the plurality of field optical elements for superimposing on the illumination area. The illumination optical apparatus according to claim 1, further comprising a condenser optical system. The illumination optical device according to claim 1, wherein the light source unit includes a plurality of solid light source elements provided in each of the plurality of unit areas. The illumination optics according to claim 2 or 3, wherein the plurality of field optical elements condense light beams from each of the plurality of unit areas respectively on a front focal plane of the condenser optical system or in the vicinity thereof. apparatus. 5. The optical system according to claim 2, wherein the irradiated surface and the plurality of light emitting regions are optically substantially conjugate with respect to the plurality of field optical elements and the condenser optical system. The illumination optical device according to 1. 6. The illumination optical apparatus according to claim 2, wherein the plurality of field optical elements include a plurality of field lenses. The illumination optical apparatus according to any one of claims 1 to 6, wherein the plurality of unit areas include a pair of unit areas in which the plurality of light emitting regions are arranged according to mutually complementary patterns. . The illumination optical apparatus according to claim 1, wherein the control unit controls light emission outputs of the plurality of light emitting regions for each unit area. The control unit according to any one of claims 1 to 7, wherein the control unit controls the light emission outputs of the plurality of light emitting regions individually or in groups in at least one unit area of the plurality of unit areas. The illumination optical device according to Item. In the illumination optical device that illuminates the irradiated surface with light from the light source unit,
The light source unit includes a plurality of unit areas, and a control unit for controlling the luminance distribution in the plurality of unit areas,
Arranged in an optical path between the light source unit and the illuminated surface, once the light flux from each of the plurality of unit areas is once condensed, and then superimposed on the illumination area on the illuminated surface. An illumination optical device comprising a light guide optical system for the purpose. The light guide optical system is configured to superimpose a plurality of field optical elements for condensing light beams from the plurality of unit areas and a light beam from each of the plurality of field optical elements on the irradiated surface. A condenser optical system,
The illumination optical apparatus according to claim 10, wherein the irradiated surface and the plurality of unit areas are optically substantially conjugate with respect to the plurality of field optical elements and the condenser optical system. An exposure apparatus comprising the illumination optical apparatus according to claim 1, wherein a mask pattern illuminated by the illumination optical apparatus is exposed on a photosensitive substrate. An exposure process comprising: an illumination process for illuminating a mask using the illumination optical apparatus according to claim 1; and an exposure process for exposing a pattern of the mask onto a photosensitive substrate. Method.

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