Imaging apparatus, exposure apparatus, and method for manufacturing article

Abstract

The invention relates to an imaging apparatus, an exposure apparatus, and a method of manufacturing an article. A small imaging apparatus capable of adopting a plurality of illumination modes is provided. An imaging device according to the present invention is characterized by being provided with: an illumination unit for causing illumination light to enter an object, the illumination unit including an illumination region adjustment unit capable of performing a first adjustment in which illumination light is emitted to the object, and a second adjustment in which illumination light is emitted to the object; a first adjustment for adjusting an illumination region in which the object is illuminated by the illumination light such that the illumination light including the light of the predetermined wavelength enters a large amount of the first region of the first region and the second region of the object, and a second adjustment for adjusting the illumination region such that the illumination light enters a large amount of the second region of the first region and the second region; an imaging unit that acquires an image of the object by receiving light from the object; and a mounting table having a mounting surface on which an object is mounted and which reflects light having a predetermined wavelength.

Description

Technical Field

[0001] The present invention relates to an imaging device, an exposure device, and a method for manufacturing an article. Background Art

[0002] Conventionally, there is known an imaging device that adopts an epi-illumination method in which illumination light is incident perpendicularly on an object from the side where an imaging optical system is provided, that is, from the front side of the object, and an imaging element receives regular reflected light from the object.

[0003] An imaging device adopting such an epi-illumination method is relatively used for imaging various objects, and is particularly suitable for imaging objects with clear outlines.

[0004] In addition, in the past, it is known that there is an imaging device that uses an oblique incident illumination (side illumination) method in which illumination light having an incident angle greater than the numerical aperture of the imaging optical system is obliquely incident on an object in a non-vertical and non-parallel direction from the surface side, and the imaging element receives scattered light from the object.

[0005] In an imaging device that adopts such an oblique incident illumination method, it is possible to obtain an image in which the outline of an object is emphasized.

[0006] Patent document 1 discloses an imaging device that improves the contrast of edges, notches, text, etc. in an acquired image by obliquely incident illumination light from multiple non-perpendicular and non-parallel directions onto the main surface of a substrate having edges, notches, text, etc.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2022-169211 Summary of the invention

[0010] Also, as an imaging device, there is known an example of a backside transmission illumination method in which illumination light is incident on an object from the back side of the object opposite to the side where an imaging optical system is provided, and the imaging element receives the transmitted light that has passed through the object.

[0011] In an imaging device adopting such a back-transmission illumination method, when an object is provided with both a transmissive portion and a light-shielding portion, a difference in brightness is generated between the two portions, and therefore a high-contrast image can be obtained for such an object.

[0012] That is, depending on the structure and optical characteristics of the object, the illumination method suitable for obtaining a high-contrast image of the object varies among the epi-illumination method, the oblique-incidence illumination method, and the back-transmission illumination method.

[0013] Therefore, in an imaging device that adopts a plurality of illumination methods and can select an appropriate illumination method according to the structure and optical characteristics of an object, it is possible to obtain high-contrast images of various objects.

[0014] However, for example, in order to adopt both oblique incident illumination and back transmission illumination, light sources for emitting illumination light are provided on the same side and opposite side relative to the imaging optical system, and when multiple illumination methods are adopted in the imaging device, there is a concern that the imaging device may become larger.

[0015] Therefore, an object of the present invention is to provide a small imaging device capable of adopting a plurality of lighting methods.

[0016] The imaging device of the present invention is characterized in that it comprises: an illumination unit for causing illumination light to be incident on an object, the illumination unit including an illumination area adjustment unit capable of performing a first adjustment and a second adjustment, wherein in the first adjustment, the illumination area for illuminating the object with illumination light is adjusted in such a manner that illumination light including light of a predetermined wavelength is incident on a first area of ​​the object and a first area of ​​a second area in large quantities, and in the second adjustment, the illumination area is adjusted in such a manner that illumination light including light of a predetermined wavelength is incident on a first area of ​​the object and a first area of ​​a second area in large quantities; an imaging unit for acquiring an image of the object by receiving light from the object; and a mounting table having a mounting surface for mounting the object and reflecting light of a predetermined wavelength.

[0017] According to the present invention, a small imaging device capable of adopting a plurality of lighting methods can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic cross-sectional view of an exposure apparatus including the position measuring device according to the present embodiment.

[0019] Figure 2 This is a top view of an alignment mark formed on a flat plate.

[0020] Figure 3 It is a cross-sectional view of the position measuring device according to the first embodiment.

[0021] Figure 4 FIG. 1 is a diagram showing an example of an image formed on an imaging surface in the position measuring device according to the first embodiment.

[0022] Figure 5 It is a cross-sectional view of the position measuring device according to the first embodiment.

[0023] Figure 6 It is a cross-sectional view of a position measuring device according to a second embodiment.

[0024] Figure 7It is a cross-sectional view of a position measuring device according to a second embodiment.

[0025] Figure 8 It is a cross-sectional view of a position measuring device according to a third embodiment.

[0026] Fig. 9 It is a cross-sectional view of a position measuring device according to a third embodiment.

[0027] Fig.10 This is a cross-sectional view of a conventional position measuring device.

[0028] Fig.11 The diagrams show examples of images formed on an imaging surface in each of the conventional position measuring devices adopting the epi-illumination method, the oblique incident illumination method, and the back-transmitted illumination method. DETAILED DESCRIPTION

[0029] Hereinafter, the imaging device according to the present embodiment will be described in detail with reference to the attached drawings. In addition, in the drawings shown below, the present embodiment is depicted with a scale different from the actual scale in order to facilitate understanding of the present embodiment.

[0030] In addition, below, the direction parallel to the optical axis of the projection optical system 40 is defined as the Z direction, and in a plane perpendicular to the Z direction (the flat surface of the flat plate 60), the scanning direction of the mask 20 and the flat plate 60 is defined as the Y direction, and the non-scanning direction orthogonal to the Y direction is defined as the X direction.

[0031] [First embodiment]

[0032] In the photolithography process included in the manufacturing process of semiconductor devices, liquid crystal displays, etc., an exposure device is used to transfer a pattern formed on an original plate such as an intermediate mask or a mask to a substrate such as a wafer or a glass plate coated with a photosensitive agent via a projection optical system.

[0033] Furthermore, in the exposure device, in order to accurately transfer the pattern of the original plate to the substrate, the original plate and the substrate must be aligned with high precision, so a position measuring device for measuring the positions of the original plate and the substrate is provided according to this requirement.

[0034] Generally, when measuring the positions of the original plate and the substrate, the positions of the alignment marks drawn on the original plate and the substrate are measured by imaging the alignment marks respectively using a dedicated imaging device (observation device, microscope).

[0035] In addition, in the original plate and the substrate, the alignment marks are generally drawn using materials such as metals and insulating films, and the optical properties, thickness, taper angle, etc. of the materials vary depending on the conditions of the manufacturing process.

[0036] In addition, a photosensitive agent for exposure is often applied to the surface of the alignment mark drawn on the substrate.

[0037] As the photosensitive agent, various photosensitive agents having mutually different optical characteristics are used according to the manufacturing process of semiconductor devices, liquid crystal displays, and the like.

[0038] Therefore, in particular, an imaging device for measuring the position of an alignment mark formed on a substrate is required to be able to cope with various optical characteristics of a coated photosensitive agent, that is, to have high measurement robustness.

[0039] That is, in an imaging device for measuring the position of an alignment mark formed on a substrate, it is preferable to be configured so that optical parameters can be changed in order to cope with various optical characteristics of a photosensitive agent applied on the substrate.

[0040] Such optical parameters include, for example, illumination methods such as incident illumination, oblique incident illumination (side illumination), and back-transmitted illumination.

[0041] In the epi-illumination method, illumination light is vertically incident on the object from the side where an imaging optical system such as an objective lens is provided, that is, from the front side of the object, and mainly regular reflected light from the object is received by an imaging element.

[0042] This type of epi-illumination method is relatively used for imaging various objects, and is particularly suitable for imaging objects with clear outlines.

[0043] In the oblique incident illumination method, illumination light having an incident angle greater than the numerical aperture of the imaging optical system is obliquely incident on the object from the front side of the object, and scattered light from the object is received by the imaging element.

[0044] In such an oblique incident illumination method, in order to increase the intensity of scattered light by increasing the intensity of illumination light, a relatively bright light source is required.

[0045] On the other hand, since it can emphasize the outline of the object, it may be useful for objects whose outline contrast becomes low under other lighting methods.

[0046] In the back transmission illumination method, illumination light is incident on the object from the back side of the object, which is the side opposite to the side where the imaging optical system is provided, and the transmitted light that has passed through the object is received by the imaging element.

[0047] In such a back-transmission illumination method, when a transmissive portion and a light-shielding portion are formed on an object, a difference in brightness is generated between the two portions, and thus such an object can be imaged with a high contrast.

[0048] As described above, in an imaging device, effective illumination methods differ among the epi-illumination method, the oblique incident illumination method, and the back-transmitted illumination method, depending on the structure and optical characteristics of the object.

[0049] That is, in order to achieve higher measurement robustness in the imaging device, it is preferable to have a plurality of the above-mentioned illumination methods.

[0050] However, in order to perform illumination by back transmission illumination, generally, a light source is embedded in a mounting table for mounting an object, or illumination light is guided from an external light source to the back side of the mounting table for mounting an object.

[0051] In this case, the structure of the lower portion of the mounting table becomes complicated, and there is a concern that the size and cost may increase.

[0052] Furthermore, in an imaging device that adopts an epi-illumination method or an oblique-incident illumination method, if such a structure is added in order to implement a back-transmitted illumination method, this also leads to an increase in size and cost.

[0053] Furthermore, when illuminating light is emitted from a light source provided on the back side of an object in an imaging device adopting a back transmission illumination method, a region through which the illuminating light passes on a placement surface of a placement table on which the object is placed needs to be formed as a transmission region.

[0054] That is, in an exposure device that uses a camera device that adopts such a back-side transmission illumination method to measure the position of the alignment mark on the substrate, there is a concern that the exposure performance of the exposure device will be reduced due to the area of ​​a part of the substrate mounting surface of the substrate mounting table being formed as a transmission area.

[0055] For example, when the substrate is made of glass, after the exposure light passes through the substrate, reflected light and scattered light are generated on the substrate mounting surface of the mounting table, and the photosensitive agent coated on the substrate is exposed using the generated reflected light and scattered light.

[0056] At this time, when a part of the substrate mounting surface of the substrate mounting table is formed as a transmission area, since the intensity of the generated reflected light and scattered light varies depending on the position within the substrate surface, uneven exposure occurs in the photosensitive agent coated on the substrate, thereby reducing the resolution performance during exposure.

[0057] Furthermore, in order to improve productivity, the exposure apparatus is configured to enable rapid acceleration and rapid stop of a substrate stage, and therefore the substrate is often sucked and held on the substrate stage by vacuum suction or the like.

[0058] In this case, when a part of the substrate placement surface of the substrate placement table is formed as a transmission area, the suction function of the substrate in the substrate placement table is reduced.

[0059] In addition, in the exposure apparatus, the substrate mounting surface formed as the substrate mounting table has high flatness.

[0060] Therefore, when a part of the substrate placement surface of the substrate placement table is formed as a transmission area, it is difficult to maintain a high flatness of the substrate placement surface.

[0061] In view of the above, an object of the present embodiment is to provide an imaging device that adopts a plurality of illumination methods, is compact and low-cost, and can suppress a decrease in the exposure performance of an exposure device when mounted on the exposure device.

[0062] Figure 1 A schematic cross-sectional view of an exposure apparatus 1 including a position measuring device 50 as an imaging device according to the first embodiment is shown.

[0063] The exposure apparatus 1 includes an illumination optical system 10 , a mask stage 30 , a projection optical system 40 , a position measuring device 50 according to the present embodiment, and a plate stage 70 (substrate stage).

[0064] The illumination optical system 10 is configured to uniformly illuminate a mask 20 (original plate) on which a pattern is drawn by irradiating exposure light with a predetermined light amount and angle distribution.

[0065] The mask stage 30 is configured to be driven in the X direction, the Y direction, and the rotation direction around an axis parallel to the Z direction while holding the mask 20 .

[0066] The projection optical system 40 is arranged between the mask stage 30 and the plate stage 70 , and guides the exposure light passing through the mask 20 to the plate 60 to project an image of the pattern formed on the mask 20 onto the plate 60 (substrate).

[0067] The plate stage 70 is configured to be driven in the X direction, the Y direction, the Z direction, and the rotation direction around an axis parallel to the Z direction while holding the plate 60 to be exposed.

[0068] When the exposure apparatus 1 adopts a scanning method in which the mask stage 30 and the plate stage 70 are scanned simultaneously to perform exposure, the mask stage 30 and the plate stage 70 need to be synchronized with each other.

[0069] Furthermore, in order to synchronize the two, it is necessary to perform alignment between the mask stage 30 and the plate stage 70 using the alignment marks drawn on the mask 20 and the alignment marks 601 drawn on the plate 60 .

[0070] Therefore, the exposure apparatus 1 is provided with the position measuring device 50 according to the present embodiment for measuring the position of the alignment mark 601 on the flat plate 60 .

[0071] Specifically, the control unit (not shown) obtains (measures) the position of the alignment mark 601 in the plane perpendicular to the optical axis of the projection optical system 40 from the image of the alignment mark 601 on the flat plate 60 obtained by the position measuring device 50 according to this embodiment.

[0072] Then, the control unit adjusts the position of the plate stage 70 according to the acquired position of the alignment mark 601 .

[0073] Specifically, the position measuring device 50 according to the present embodiment adopts an OFF-AXIS method, and the detailed structure will be described later.

[0074] In addition, the exposure device 1 is also provided with a position measuring device of a through-the-lens (TTL) or through-the-mirror (TTM) method (not shown).

[0075] Then, the relative position between the position measuring device and the position measuring device 50 according to the present embodiment is acquired in advance.

[0076] Thus, by measuring the position of the alignment mark 601 on the plate 60 using the position measuring device 50 according to the present embodiment, it is possible to align the alignment mark on the mask 20 with the alignment mark 601 on the plate 60 .

[0077] Furthermore, the position measuring device 50 according to the present embodiment may also have a function of adjusting the focus of the measurement plate 60 .

[0078] Next, the detailed structure of the position measuring device 50 according to the present embodiment will be described.

[0079] first, Fig.10 A schematic cross-sectional view of a conventional position measuring device 550 for measuring the position of an alignment mark provided on a plate 60 of an exposure device is shown.

[0080] Specifically, the position measurement device 550 adopts an epi-illumination method and includes an illumination unit 51 and an imaging unit 52 .

[0081] The lighting unit 51 is provided with a light source 511 and an illumination optical system 512 .

[0082] As the light source 511 , an LED, a lamp, or the like can be used. Instead of providing the light source 511 , a light guide such as an optical fiber may be used to guide light to the illumination optical system 512 .

[0083] The illumination optical system 512 includes a condenser lens, a field stop, and the like, converts light emitted from the light source 511 into illumination light, and guides the illumination light to the beam splitter 513 .

[0084] The imaging unit 52 is provided with a beam splitter 513 , an aperture stop 521 , an objective lens 522 , a relay lens 523 , and an imaging element 542 .

[0085] Then, the illumination light guided to the beam splitter 513 is reflected by the beam splitter 513 and condensed at the position of the aperture stop 521 .

[0086] Thereafter, the illumination light having passed through the aperture stop 521 is guided to the region on the flat plate 60 where the alignment mark is formed through the objective lens 522 , so that the alignment mark is illuminated.

[0087] Then, the reflected light reflected by the alignment mark on the illuminated flat plate 60 passes through the objective lens 522 , the aperture stop 521 , the beam splitter 513 , and the relay lens 523 in this order, and is guided to the imaging surface of the imaging element 542 .

[0088] As a result, an image of the alignment mark on the flat plate 60 is formed on the imaging surface of the imaging element 542 .

[0089] Then, by processing the image of the alignment mark formed on the imaging surface of the imaging element 542 , the position of the alignment mark on the plate 60 is measured.

[0090] Here, it is assumed that the flat plate 60 is formed with Figure 2 Alignment mark 601 is shown.

[0091] Specifically, in the alignment mark 601 , three rectangles (first portion) extending in the Y direction and spaced apart from each other at equal intervals in the X direction are formed in the center.

[0092] In the alignment mark 601 , two sets of two rectangles extending in the X direction and spaced apart from each other in the Y direction are formed so as to sandwich the three rectangles in the Y direction.

[0093] Furthermore, each rectangle in the alignment mark 601 is formed of a metal film such as chromium, and reflects the irradiated light with a high reflectivity.

[0094] In addition, a glass portion 602 (second portion) is provided around each rectangular shape in the alignment mark 601, and the glass portion 602 transmits the irradiated light with a high transmittance.

[0095] Here, the above-mentioned rectangles and the glass portion 602 are Figure 2 The rectangle indicated by the dashed line is called the alignment mark 601.

[0096] Furthermore, the area around the alignment mark 601 in the flat plate 60 is also formed by the glass portion 602 .

[0097] Also, consider using Fig.10 The conventional position measuring device 550 shown in FIG. Figure 2 The position of the alignment mark 601 is shown.

[0098] At this time, on the imaging surface of the imaging element 542 in the position measuring device 550, a Fig.11 The image shown in (a).

[0099] That is, the illumination light irradiated onto the alignment mark 601 is regularly reflected by each rectangle included in the alignment mark 601 , so that a bright image of each rectangle is formed on the imaging surface of the imaging element 542 .

[0100] On the other hand, since the illumination light passes through the glass portion 602 and almost no regular reflected light is generated, the light does not reach the inside of the imaging portion 52 , and the area corresponding to the glass portion 602 on the imaging surface of the imaging element 542 becomes dark.

[0101] Therefore, in the image formed on the imaging surface of the imaging element 542, a difference in brightness (contrast difference) occurs between each rectangular image and the region corresponding to the glass portion 602, thereby enabling the alignment mark 601 to be imaged, that is, the position of the alignment mark 601 to be measured.

[0102] Next, consider measuring with oblique incident illumination Figure 2 The position of the alignment mark 601 is shown.

[0103] Fig.11 (b) shows the position measurement device using the oblique incident illumination method in the past. Figure 2 The position of the alignment mark 601 shown is an image formed on the imaging surface of the imaging element.

[0104] In a conventional position measuring device adopting the oblique incident illumination method, an illumination unit is provided so that illumination light is obliquely incident from a non-perpendicular and non-parallel direction onto the flat surface of the flat plate 60 on which the alignment mark 601 is formed.

[0105] Furthermore, an imaging unit is provided at a position facing the flat plate surface of the flat plate 60 in a direction perpendicular to the flat plate surface so as to receive light from the flat plate surface.

[0106] In such an oblique incident illumination structure, illumination light obliquely incident on the alignment mark 601 at an incident angle greater than the numerical aperture of the imaging optical system provided in the imaging unit is reflected in a direction non-perpendicular to the flat surface at the center of each rectangle included in the alignment mark 601.

[0107] Therefore, on the imaging surface of the imaging element provided in the imaging unit, a bright image of the central portion of each rectangle of the alignment mark 601 is not formed, that is, the area corresponding to the central portion of each rectangle becomes dark.

[0108] In addition, since the illumination light is transmitted through the glass portion 602 and almost no regular reflected light is generated, the light does not reach the inside of the imaging portion, and the area corresponding to the glass portion 602 on the imaging surface of the imaging element becomes dark.

[0109] On the other hand, near the end portions of each rectangle included in the alignment mark 601, the incident illumination light is scattered.

[0110] Then, part of the scattered light generated by scattering near the end portions of each rectangle reaches the inside of the imaging unit and is received on the imaging surface of the imaging element.

[0111] Therefore, if Fig.11 As shown in (b) of FIG. 1 , when the alignment mark 601 is illuminated in a conventional position measuring device using an oblique incident illumination method, an area corresponding to the vicinity of the end of each rectangle included in the alignment mark 601 becomes bright on the imaging surface of the imaging element.

[0112] That is, scattered light is dominantly detected in the area corresponding to the vicinity of the end of each rectangle on the imaging surface of the imaging element, and the area becomes brighter, while no scattered light is generated in the other areas and no regular reflected light reaches the other areas, and the area becomes darker.

[0113] Next, consider measuring the Figure 2 The position of the alignment mark 601 is shown.

[0114] Fig.11 (c) shows the measurement of the position in the conventional position measuring device using the back transmission illumination method. Figure 2 The position of the alignment mark 601 shown is an image formed on the imaging surface of the imaging element.

[0115] In a conventional position measuring device using back transmission illumination, illumination light is incident from a vertical direction on the back side of the plate 60 opposite to the plate surface on which the alignment mark 601 is formed. Then, an illumination unit is provided so that the illumination light passes through the inside of the plate 60 and illuminates the alignment mark 601.

[0116] Furthermore, an imaging unit is provided at a position facing the flat plate surface of the flat plate 60 in a direction perpendicular to the flat plate surface so as to receive light from the flat plate surface.

[0117] In such a back transmission illumination system, for example, when each rectangle included in the alignment mark 601 is formed of a metal film such as chromium, the illumination light incident on each rectangle is shielded.

[0118] Therefore, on the imaging surface of the imaging element provided in the imaging unit, a bright image of each rectangle of the alignment mark 601 is not formed, that is, the area corresponding to each rectangle becomes dark.

[0119] On the other hand, since the illumination light passes through the glass portion 602 , the light reaches the inside of the imaging portion, and the area corresponding to the glass portion 602 on the imaging plane of the imaging element becomes brighter.

[0120] Therefore, if Fig.11 As shown in (c) of FIG. 1 , when the alignment mark 601 on the plate 60 is illuminated in a conventional position measuring device using a back transmission illumination method, the area corresponding to each rectangle included in the alignment mark 601 becomes dark on the imaging surface of the imaging element.

[0121] On the other hand, on the imaging surface of the imaging element, the area other than the rectangular areas of the alignment mark 601, that is, the area corresponding to the glass portion 602, becomes bright.

[0122] Figure 3 (a) is a schematic cross-sectional view of a position measuring device 50 according to the present embodiment.

[0123] The position measuring device 50 according to the present embodiment includes an illumination unit 53 for illuminating a flat plate 60 as an object (test object) by causing illumination light to enter the flat plate 60 , and a flat plate mounting table 70 (mounting table) having a mounting surface on which the flat plate 60 is mounted.

[0124] Furthermore, an alignment mark 601 is formed on the flat surface of the flat plate 60 .

[0125] Furthermore, the position measurement device 50 according to the present embodiment includes an imaging unit 54 that acquires an image of the flat plate 60 by receiving light from the flat plate 60 .

[0126] like Figure 3 As shown in (a) of FIG. 5 , the illumination unit 53 is arranged so that illumination light is incident obliquely on the flat surface (predetermined surface) of the flat plate 60 from a non-vertical and non-parallel direction.

[0127] In other words, the optical axis of the illumination unit 53 is neither perpendicular nor parallel to the flat surface of the flat plate 60 .

[0128] Furthermore, in other words, the lighting unit 53 is configured so that the illumination light is incident on the flat surface of the flat plate 60 at an incident angle greater than the numerical aperture of the imaging optical system 541 provided in the imaging unit 54 in such a manner that the regular reflected light generated by the alignment mark 601 cannot be detected in the imaging unit 54.

[0129] Specifically, the illumination unit 53 includes a light source 531 and an illumination optical system 532 .

[0130] As the light source 531 , an LED, a lamp, or the like can be used. Instead of providing the light source 531 , a light guide such as an optical fiber may be used to guide light to the illumination optical system 532 .

[0131] In addition, the light source 531 is preferably configured so that the amount of light emitted can be variable.

[0132] In addition, the light source 531 is configured to emit light having wavelengths with different transmittances between each rectangle included in the alignment mark 601 and the glass portion 602 .

[0133] In addition, although the illumination unit 53 includes a single light source 531 , a plurality of light sources 531 may be used to change the wavelength, or the wavelength may be changed by using a plurality of wavelength cutoff filters in a single light source 531 that emits light in a wider wavelength band.

[0134] In addition, the light source 531 does not need to be configured to emit light of a single wavelength, that is, the light emitted from the light source 531 only needs to include light of a predetermined wavelength.

[0135] The illumination optical system 532 includes a condenser lens, a field aperture 533 , an illumination region adjustment unit 534 , an aperture stop 535 , and a projection lens, converts light emitted from the light source 531 into illumination light, and guides the illumination light to the flat surface of the flat plate 60 .

[0136] Specifically, in the illumination optical system 532 , a field stop 533 for limiting the beam diameter of the illumination light is provided at a position optically conjugate with the flat plate 60 , and an aperture stop 535 for adjusting the light amount of the illumination light is also provided.

[0137] In addition, the illumination optical system 532 preferably further includes a wavelength plate or the like capable of changing the polarization of the illumination light as necessary.

[0138] In addition, the illumination optical system 532 is preferably configured to be able to adjust the numerical aperture.

[0139] In addition, the illumination unit 53 is preferably configured to be able to adjust the incident angle of the illumination light on the flat surface of the flat plate 60 so that an image of the alignment mark 601 with a high contrast is formed on the imaging unit 54 .

[0140] Specifically, the illumination unit 53 is preferably configured to be able to adjust the emission angle of the illumination light so that the illumination light can be incident on the flat surface of the flat plate 60 at an incident angle greater than the numerical aperture of the imaging optical system 541 included in the imaging unit 54 .

[0141] In addition, in the position measuring device 50 according to the present embodiment, a plurality of illumination units 53 may be provided so that the illumination unit 53 that irradiates illumination light can be selected according to the optical characteristics of the alignment mark 601 .

[0142] For example, when the alignment mark 601 has an optical property that is sensitive to the incident angle of the illumination light in the XY plane, the alignment mark 601 may be illuminated from all directions in the XY plane using the ring-shaped light source 531 .

[0143] In addition, for example, in addition to the light source 531 for oblique incident illumination described above, a light source for epi-illumination for illuminating the alignment mark 601 from a vertical direction may be provided.

[0144] Furthermore, in the position measuring device 50 according to the present embodiment, an illumination region adjustment unit 534 for adjusting an illumination region on the plate surface of the plate 60 is provided near the field aperture 533 .

[0145] In other words, the illumination region adjustment unit 534 is disposed closest to the field stop 533 included in the optical element of the illumination unit 53 .

[0146] Specifically, the illumination region adjustment unit 534 provided in the position measurement device 50 according to the present embodiment is a light shielding unit such as an aperture that shields a part of the illumination light.

[0147] Then, by rotating the illumination region adjustment portion 534 as such a light shielding portion around the optical axis of the illumination portion 53 and arranging it at a predetermined angle, it is possible to adjust the illumination region on the flat plate surface of the flat plate 60 .

[0148] Furthermore, by disposing the illumination region adjustment unit 534 in a displaced manner in a predetermined direction perpendicular to the optical axis of the illumination unit 53 , it is possible to adjust the illumination region on the flat surface of the flat plate 60 .

[0149] In addition, a plurality of light shielding portions having different shapes are provided in the illumination region adjusting portion 534 , and the illumination region on the flat surface of the flat plate 60 can be adjusted by selecting a predetermined light shielding portion, in other words, replacing the light shielding portion.

[0150] In addition to the above-mentioned structure, the illumination area in the alignment mark 601 may be adjusted by driving the flat plate stage 70 .

[0151] The imaging unit 54 includes an imaging element 542 that receives light from the flat plate 60 , and an imaging optical system 541 that includes an objective lens, an aperture stop, and a relay lens, guides light from the flat plate 60 to the imaging element 542 , and has an optical axis perpendicular to the flat surface of the flat plate 60 .

[0152] The plate stage 70 is a stage having a driving shaft and is used in the exposure apparatus 1 adopting the scanning method, the stepper method, etc. as described above, and is provided with a vacuum chuck or the like for sucking and holding the plate 60 .

[0153] In addition, the flat plate stage 70 preferably has a high-flatness mounting surface formed of a material with a low thermal expansion coefficient that is not easily reflected or scattered against the illumination light in the position measuring device 50 involved in this embodiment, and is not easily reflected or scattered against the exposure light in the exposure device 1.

[0154] Figure 3 (b) shows a state where the illumination is performed without adjusting the illumination area on the flat plate surface of the flat plate 60 by the illumination area adjustment unit 534 in the position measurement device 50 according to the present embodiment.

[0155] At this time, if Figure 3 As shown in FIG. 2 ( b ), the illumination light from the illumination unit 53 is incident on both the alignment mark 601 on the flat surface of the flat plate 60 and the glass portion 602 around the alignment mark 601 .

[0156] In addition, Figure 3 In (b), the alignment mark 601 is shown enlarged to make the regular reflected light and scattered light from the alignment mark 601 easier to observe, and attention should be paid to the fact that the illumination light 55 from the illumination unit 53 is incident on the entire alignment mark 601.

[0157] in addition, Figure 3 The arrows in (b) represent the directions in which each representative light ray travels.

[0158] About these Figure 5 The same is true for (a) and (b).

[0159] First, of the illumination light 55 included in the illumination light from the illumination unit 53 and directly incident on the alignment mark 601 , light incident on the central portion of each rectangle included in the alignment mark 601 is reflected by the central portion of each rectangle to generate regular reflection light 551 .

[0160] Furthermore, since the generated regular reflection light 551 has a reflection angle greater than the numerical aperture of the imaging optical system 541 provided in the imaging section 54 , it does not reach the imaging surface of the imaging element 542 .

[0161] Therefore, a bright image in the center of each rectangle is not formed on the imaging plane of the imaging element 542 .

[0162] Next, light incident on the vicinity of the ends of each rectangle included in the alignment mark 601 among the illumination light 55 included in the illumination light from the illumination unit 53 and directly incident on the alignment mark 601 is scattered near the ends of each rectangle to generate scattered light 552 .

[0163] Furthermore, since the scattered light 552 has a scattering angle smaller than the numerical aperture of the imaging optical system 541 provided in the imaging section 54, a part of the generated scattered light 552 reaches the imaging surface of the imaging element 542 and is received.

[0164] Therefore, the areas corresponding to the ends of the rectangles on the imaging plane of the imaging element 542 become brighter.

[0165] That is, from the regular reflected light 551 and the scattered light 552, Fig.11 (b) The same result as the oblique incident illumination method shown above.

[0166] Next, most of the illumination light 56 ​​included in the illumination light from the illumination unit 53 and incident on the glass portion 602 around the alignment mark 601 passes through the incident glass portion 602 .

[0167] Thus, the incident light 561 reaches the placement surface of the flat plate 60 in the flat plate placement table 70 .

[0168] Incident light 561 is reflected by the placement surface of flat plate placement table 70 to generate reflected light 562 , and is scattered by the placement surface to generate scattered light 563 .

[0169] At this time, since the flat plate 60 has a thickness, a part of each of the reflected light 562 and the scattered light 563 is incident on each rectangle included in the alignment mark 601 from the lower side in the Z direction.

[0170] Furthermore, when viewed in the XY plane, the portion of each of the reflected light 562 and the scattered light 563 is totally reflected and scattered multiple times inside the flat plate 60 and diffused in various directions, thereby entering each rectangle included in the alignment mark 601 from various directions.

[0171] In this way, the portion of each of the reflected light 562 and the scattered light 563 indirectly illuminates the alignment mark 601 .

[0172] Moreover, light 564 transmitted through the flat surface of the flat plate 60 in the reflected light 562 and the scattered light 563, which travels in a direction forming an angle smaller than the numerical aperture of the imaging optical system 541 relative to the normal line of the flat surface of the flat plate 60, arrives at the imaging surface of the imaging element 542.

[0173] On the other hand, light 565 of the reflected light 562 and the scattered light 563 that is shielded by being incident on each rectangle included in the alignment mark 601 does not reach the imaging surface of the imaging element 542 .

[0174] Therefore, the area corresponding to the glass portion 602 other than the rectangles included in the alignment mark 601 becomes bright on the imaging surface of the imaging element 542 .

[0175] That is, from the reflected light 562 and the scattered light 563, Fig.11 (c) The same result as the back transmission lighting method shown above.

[0176] As described above, in the position measurement device 50 according to the present embodiment, when the illumination area on the flat surface of the flat surface 60 is not adjusted by the illumination area adjustment unit 534, a picture such as the following is obtained on the imaging surface of the imaging element 542. Figure 4 Image shown.

[0177] Right now, Figure 4 The image formed on the imaging surface of the imaging element 542 by both the oblique incident illumination method and the back transmission illumination method is shown, and it can be seen that the contrast between each rectangle included in the alignment mark 601 and the glass portion 602 outside the rectangle is reduced.

[0178] Furthermore, when an attempt is made to measure the position of the registration mark 601 based on an image having a low contrast, there is a possibility that an undesirable result such as erroneous measurement may occur.

[0179] That is, the positioning accuracy of the plate 60 may be reduced due to the erroneous measurement of the position of the alignment mark 601 , and there is a possibility that the superposition accuracy may be reduced when the plate 60 is exposed in the exposure apparatus 1 .

[0180] Therefore, in the position measurement device 50 according to the present embodiment, an illumination region adjustment unit 534 for adjusting the illumination region on the plate surface of the plate 60 is provided near the field aperture 533 included in the illumination unit 53 .

[0181] Thus, by illuminating the alignment mark 601 by selecting either the oblique incident illumination method or the back transmission illumination method while using the same light source 531 , a high-contrast image of the alignment mark 601 can be obtained on the imaging plane of the imaging element 542 .

[0182] Figure 5 (a) shows a state in which the illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 534 is illuminated in the position measurement device 50 according to the present embodiment.

[0183] Specifically, in Figure 5 In the structure shown in (a) of FIG. 6 , the illumination light 56 ​​incident on the glass portion 602 around the alignment mark 601 is shielded by the illumination region adjustment portion 534 .

[0184] Thus, the illumination area on the plate surface of the plate 60 is illuminated only by the illumination light 55 directly incident on the alignment mark 601 .

[0185] In this case, by selecting the above-mentioned oblique incident illumination method, it is possible to reduce the reflected light 562 and the scattered light 563 that illuminate the alignment mark 601 from below.

[0186] Therefore, scattered light 552 generated by scattering near the ends of each rectangle included in the alignment mark 601 reaches the imaging surface of the imaging element 542 and is received, so that only the ends of each rectangle are bright, as shown in FIG. Fig.11 (b) is an image with higher contrast.

[0187] Figure 5 (b) shows a state where another illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 534 is illuminated in the position measurement device 50 according to the present embodiment.

[0188] Specifically, in Figure 5 In the structure shown in (b) of FIG. 6 , the illumination light 55 directly incident on the alignment mark 601 is shielded by the illumination area adjustment unit 534 .

[0189] Thus, the illumination area on the flat plate surface of the flat plate 60 is illuminated only by the illumination light 56 ​​incident on the glass portion 602 around the alignment mark 601 .

[0190] In this case, by selecting the above-mentioned back transmission lighting method, the illumination light 55 that illuminates the alignment mark 601 from above can be reduced.

[0191] Therefore, the reflected light 562 generated on the placement surface of the flat plate 60 in the flat plate stage 70 and the light 564 transmitted through the flat plate surface of the flat plate 60 among the scattered light 563 reach the imaging surface of the imaging element 542 and are received.

[0192] Thus, only the area outside the rectangles of the alignment mark 601 is bright, as shown in FIG. Fig.11 (c) is an image with higher contrast.

[0193] In the position measuring device 50 according to the present embodiment, the illumination area on the flat surface can be switched so that the illumination light is incident only on the alignment mark 601 or the illumination light is incident only on the glass portion 602 around the alignment mark 601 as described above.

[0194] In other words, in the position measuring device 50 according to the present embodiment, the illumination area on the flat plate surface illuminated by the illumination light can be adjusted so that a large amount of illumination light is incident on one of the first area and the second area on the flat plate surface.

[0195] For example, the illumination area on the flat surface is adjusted using the illumination area adjustment unit 534 (first adjustment) so that a large amount of illumination light is incident on the first area including at least a portion of the alignment mark 601 and the second area including at least a portion of the glass portion 602.

[0196] Thus, the alignment mark 601 can be illuminated by the oblique incident illumination method, and an image of the flat surface including the alignment mark 601 corresponding to the oblique incident illumination method can be acquired.

[0197] In addition, the illumination area on the flat surface is adjusted by the illumination area adjustment unit 534 (second adjustment) so that a large amount of illumination light is incident on the first area including at least a portion of the alignment mark 601 and the second area including at least a portion of the glass portion 602.

[0198] Thus, the alignment mark 601 can be illuminated by the back surface transmission illumination method, and an image of the flat surface including the alignment mark 601 corresponding to the back surface transmission illumination method can be acquired.

[0199] In this way, the illumination region adjustment unit 534 of the illumination unit 53 provided in the position measurement device 50 according to the present embodiment is configured to be able to perform the above-mentioned first adjustment and the above-mentioned second adjustment.

[0200] That is, by using the same light source 531 to illuminate the alignment mark 601 in an illumination method selected from the oblique incident illumination method and the back surface transmission illumination method, an image of the alignment mark 601 with a high contrast can be obtained.

[0201] In this case, a control unit (not shown) may be provided to select one of the oblique incident illumination method and the back transmission illumination method based on parameters (input parameters) input to the control unit and obtain an image of the flat plate 60 using the imaging unit 54 .

[0202] Such parameters include, for example, the material of the plate 60, the photosensitive agent coated on the plate surface of the plate 60, the rectangles included in the alignment mark 601, and the glass portion 602, specifically, optical properties such as reflectivity and transmittance with respect to incident light.

[0203] For example, when the plate 60 is made of metal, for example, which has no portion that transmits illumination light, the alignment mark 601 cannot be illuminated by the back transmission illumination method, so the oblique incident illumination method is selected.

[0204] On the other hand, when the flat plate 60 has a portion such as the glass portion 602 that transmits illumination light, it is possible to select one of the oblique incident illumination method and the back transmission illumination method for obtaining an image with a higher contrast according to the above-mentioned optical properties.

[0205] Furthermore, when it is not possible to select either the oblique incident illumination method or the back transmission illumination method based on the optical properties, the image of the flat plate 60 can be acquired by the imaging unit 54 and the image with higher contrast can be selected from the two images.

[0206] In addition, the position measuring device 50 according to the present embodiment can be combined with the above-mentioned epi-illumination method.

[0207] That is, for example, in a position measuring device using the epitaxial illumination method, the position measuring device can be provided which can easily switch between the three illumination methods of the epitaxial illumination method, the oblique incident illumination method, and the back surface transmission illumination method by providing the illumination unit 53 .

[0208] As described above, in the position measuring device 50 according to the present embodiment, the illumination region on the plate surface of the plate 60 can be adjusted by providing the illumination region adjusting portion 534 as a light shielding portion that shields a portion of illumination light in the illumination portion 53 .

[0209] Thus, by illuminating the alignment mark 601 with the illumination method selected from the oblique incident illumination method and the back surface transmission illumination method, it is possible to obtain an image of the alignment mark 601 with a high contrast.

[0210] That is, in the present embodiment, it is possible to provide the position measuring device 50 that can adopt both the back transmission illumination method and the oblique incident illumination method under the constraint of the limited space in the exposure device 1 .

[0211] Thus, it is possible to provide the exposure apparatus 1 including the position measuring device 50 having high measurement robustness with a simple and low-cost configuration.

[0212] In addition, in the position measuring device 50 according to the present embodiment, Figure 5 When illumination is performed by the back transmission illumination method shown in (b), it is preferable that the illumination light 56 ​​is shielded as little as possible before reaching the mounting surface of the flat plate 60 in the flat plate mounting table 70 .

[0213] For example, when a portion of the illumination light 56 ​​is shielded by a rectangle included in another alignment mark 601 before reaching the placement surface of the plate 60 in the plate placement table 70 , reflected light 562 and scattered light 563 are generated due to the missing portion.

[0214] Then, the alignment mark 601 is illuminated by the partially missing reflected light 562 and scattered light 563 , and uneven illumination occurs in the image formed on the imaging surface of the imaging element 542 .

[0215] Therefore, when illuminating a predetermined alignment mark 601 by back transmission illumination, it is preferable that the illumination light 56 ​​be transmitted through the glass portion 602 on the plate surface of the plate 60 where no other alignment mark 601 is formed.

[0216] In the above, an example in which the position measuring device 50 according to the present embodiment is provided in the exposure device 1 is shown, but the present invention is not limited thereto and the position measuring device 50 may be provided in a pattern forming device such as a printing device or a drawing device.

[0217] Here, the printing device refers to a device that forms a pattern of a cured product to which the pattern of the mold is transferred by bringing an imprint material supplied to a substrate and a mold into contact with each other and then supplying energy for curing the imprint material.

[0218] The drawing device refers to a device that forms a pattern (latent image pattern) on a substrate by drawing on the substrate using a charged particle beam (electron beam) or a laser beam.

[0219] In addition, the present embodiment is not limited to the position measuring device 50 , but can be applied to various types of observation devices such as microscopes.

[0220] Furthermore, the position measuring device 50 according to the present embodiment is not limited to the exposure device 1 adopting the scanning method, and may be provided in an exposure device adopting other exposure methods such as the stepper method.

[0221] [Second Embodiment]

[0222] Figure 6 (a) is a schematic cross-sectional view of a position measuring device 150 according to the second embodiment.

[0223] The position measuring device 150 according to this embodiment has the same structure as the position measuring device 50 according to the first embodiment except that an illumination area adjusting unit 536 is provided instead of the illumination area adjusting unit 534 . Therefore, the same reference numerals are given to the same components and their description is omitted.

[0224] Specifically, in the position measurement device 150 according to the present embodiment, the illumination region adjustment section 536 formed of the transmission section in the illumination section 53 is provided in the vicinity of the field stop 533 .

[0225] In other words, the illumination region adjustment unit 536 is disposed closest to the field stop 533 included in the optical element of the illumination unit 53 .

[0226] More specifically, the illumination area adjustment unit 536 is, for example, a flat plate (transmission element) that transmits light emitted from the light source 531 , and is configured to be rotatable around a rotation axis that is perpendicular to the optical axis of the illumination optical system 532 .

[0227] Furthermore, by rotating the illumination region adjusting unit 536 about the rotation axis, the illumination light can be incident on the flat surface of the flat plate 60 at a position shifted in directions perpendicular to the optical axis of the illumination optical system 532 and the rotation axis.

[0228] That is, in the position measuring device 150 according to the present embodiment, the illumination area can be adjusted by changing the irradiation position of the illumination light on the flat surface of the flat plate 60 .

[0229] Figure 6 (b) shows a state in which the illumination is performed on the flat plate surface of the flat plate 60 without adjusting the illumination area on the flat plate surface by the illumination area adjustment unit 536 in the position measurement device 150 according to the present embodiment.

[0230] At this time, if Figure 6 As shown in FIG. 2 ( b ), the illumination light from the illumination unit 53 is incident on both the alignment mark 601 on the flat surface of the flat plate 60 and the glass portion 602 around the alignment mark 601 .

[0231] In addition, Figure 6 In (b), the alignment mark 601 is shown enlarged to make the regular reflected light and scattered light from the alignment mark 601 easier to observe, and attention should be paid to the fact that the illumination light 55 from the illumination unit 53 is incident on the entire alignment mark 601.

[0232] in addition, Figure 6 The arrows in (b) represent the directions in which each representative light ray travels.

[0233] About these Figure 7 The same is true for (a) and (b).

[0234] In this case, in the position measuring device 50 according to the first embodiment, if Figure 3 As described in (b) of FIG. 5 , both the illumination lights 55 and 56 are incident, thereby generating regular reflection light 551 , scattered light 552 , reflection light 562 , and scattered light 563 .

[0235] Then, part of the scattered light 552 , the reflected light 562 , and part of the light 564 transmitted through the flat plate surface of the flat plate 60 among the scattered light 563 reach the imaging surface of the imaging element 542 and are received.

[0236] Thus, in the position measurement device 150 according to the present embodiment, when the illumination area on the flat surface of the flat surface 60 is not adjusted by the illumination area adjustment unit 536, the image is obtained on the imaging surface of the imaging element 542. Figure 4 Image shown.

[0237] That is, by forming an image on the imaging surface of the imaging element 542 using both the oblique incident illumination method and the back transmission illumination method, the contrast between the rectangles included in the alignment mark 601 and the glass portion 602 outside the rectangles is reduced.

[0238] Furthermore, when an attempt is made to measure the position of the registration mark 601 based on an image having a low contrast, there is a possibility that an undesirable result such as erroneous measurement may occur.

[0239] That is, the positioning accuracy of the plate 60 may be reduced due to the erroneous measurement of the position of the alignment mark 601 , and there is a possibility that the superposition accuracy may be reduced when the plate 60 is exposed in the exposure apparatus 1 .

[0240] Therefore, in the position measurement device 150 according to the present embodiment, an illumination region adjustment unit 536 for adjusting the illumination region on the plate surface of the plate 60 is provided near the field aperture 533 included in the illumination unit 53 .

[0241] Thus, the alignment mark 601 can be illuminated by either the oblique incident illumination method or the back transmission illumination method while using the same light source 531 .

[0242] Therefore, it is possible to obtain an image of the alignment mark 601 with a high contrast on the imaging surface of the imaging element 542 .

[0243] Figure 7 (a) shows a state in which the illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 536 is illuminated in the position measurement device 150 according to the present embodiment.

[0244] Specifically, in Figure 7 In the structure shown in (a) of FIG. 5 , the illumination area adjustment section 536 is rotated so that the illumination light from the illumination section 53 directly enters the alignment mark 601 , thereby adjusting the illumination area on the flat surface of the flat plate 60 .

[0245] That is, the illumination area adjustment unit 536 does not generate the illumination light 56 ​​incident on the glass portion 602 around the alignment mark 601 , but generates only the illumination light 55 directly incident on the alignment mark 601 , thereby illuminating the illumination area.

[0246] In this case, by selecting the above-mentioned oblique incident illumination method, it is possible to reduce the reflected light 562 and the scattered light 563 that illuminate the alignment mark 601 from below.

[0247] Therefore, scattered light 552 generated by scattering near the ends of each rectangle included in the alignment mark 601 reaches the imaging surface of the imaging element 542 and is received, so that only the ends of each rectangle are bright, as shown in FIG. Fig.11 (b) is an image with higher contrast.

[0248] Figure 7 (b) shows a state in which another illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 536 is illuminated in the position measurement device 150 according to the present embodiment.

[0249] Specifically, in Figure 7 In the structure shown in (b), the illumination area on the flat surface of the flat plate 60 is adjusted by rotating the illumination area adjustment unit 536 so that the illumination light from the illumination unit 53 is incident on the glass unit 602 around the alignment mark 601 .

[0250] That is, the illumination area adjustment unit 536 does not generate the illumination light 55 that directly enters the alignment mark 601 , but generates only the illumination light 56 ​​that enters the glass portion 602 around the alignment mark 601 , thereby illuminating the illumination area.

[0251] In this case, by selecting the above-mentioned back transmission lighting method, the illumination light 55 that illuminates the alignment mark 601 from above can be reduced.

[0252] Therefore, the reflected light 562 generated on the placement surface of the flat plate 60 in the flat plate stage 70 and the light 564 transmitted through the flat plate surface of the flat plate 60 among the scattered light 563 reach the imaging surface of the imaging element 542 and are received.

[0253] Thus, only the area outside the rectangles of the alignment mark 601 is bright, as shown in FIG. Fig.11(c) is an image with higher contrast.

[0254] In the position measuring device 150 according to the present embodiment, the illumination area on the flat surface can be switched so that the illumination light is incident only on the alignment mark 601 or the illumination light is incident only on the glass portion 602 around the alignment mark 601 as described above.

[0255] That is, by using the same light source 531 to illuminate the alignment mark 601 in an illumination method selected from the oblique incident illumination method or the back transmission illumination method, an image of the alignment mark 601 with a high contrast can be obtained.

[0256] As described above, in the position measuring device 150 according to this embodiment, the illumination region on the plate surface of the plate 60 can be adjusted by providing the illumination region adjusting section 536 as a transmission section in the illumination section 53 for shifting the optical axis of the illumination section 53 in a direction perpendicular to the optical axis.

[0257] Thus, by illuminating the alignment mark 601 with the illumination method selected from the oblique incident illumination method and the back surface transmission illumination method, it is possible to obtain an image of the alignment mark 601 with a high contrast.

[0258] Furthermore, in the position measuring device 150 according to this embodiment, the light from the light source 531 can be completely incident on the flat surface of the flat plate 60 without partially shielding the light, so that a wider illumination area can be illuminated with higher illumination efficiency than the position measuring device 50 according to the first embodiment.

[0259] Furthermore, in the position measuring device 150 according to the present embodiment, in addition to the illumination region adjusting unit 536 composed of a rotatable flat plate, the illumination region adjusting unit 534 composed of a light shielding unit used in the position measuring device 50 according to the first embodiment may be provided.

[0260] [Third Embodiment]

[0261] Figure 8 (a) is a schematic cross-sectional view of a position measuring device 250 according to the third embodiment.

[0262] The position measuring device 250 according to this embodiment has the same structure as the position measuring device 50 according to the first embodiment except that an illumination area adjusting unit 537 is provided instead of the illumination area adjusting unit 534 . Therefore, the same reference numerals are given to the same components and their description is omitted.

[0263] Specifically, in the position measuring device 250 according to the present embodiment, the illumination region adjustment portion 537 formed of a reflection portion in the illumination portion 53 is provided in the vicinity of the aperture stop 535 .

[0264] In other words, the illumination region adjustment unit 537 is disposed closest to the aperture stop 535 included in the optical element of the illumination unit 53 .

[0265] More specifically, the illumination area adjustment unit 537 is, for example, a galvanometer mirror (reflection element) that reflects light emitted from the light source 531 , and is configured to be rotatable around axes perpendicular to the optical axis of the illumination optical system 532 and the normal to the reflection surface.

[0266] Furthermore, by rotating the illumination region adjusting unit 537 , that is, adjusting the angle of the reflection surface, the illumination region adjusting unit 537 changes the reflection angle of the illumination light, thereby changing the irradiation position of the illumination light on the flat plate surface of the flat plate 60 .

[0267] That is, in the position measuring device 250 according to the present embodiment, the illumination area can be adjusted by changing the irradiation position of the illumination light on the flat surface of the flat plate 60 .

[0268] Figure 8 (b) shows a state where the illumination is performed without adjusting the illumination area on the flat surface of the flat surface 60 by the illumination area adjustment unit 537 in the position measurement device 250 according to the present embodiment.

[0269] At this time, if Figure 8 As shown in FIG. 2 ( b ), the illumination light from the illumination unit 53 is incident on both the alignment mark 601 on the flat surface of the flat plate 60 and the glass portion 602 around the alignment mark 601 .

[0270] In addition, Figure 8 In (b), the alignment mark 601 is shown enlarged to make the regular reflected light and scattered light from the alignment mark 601 easier to observe, and attention should be paid to the fact that the illumination light 55 from the illumination unit 53 is incident on the entire alignment mark 601.

[0271] in addition, Figure 8 The arrows in (b) represent the directions in which each representative light ray travels.

[0272] About these Fig. 9 The same is true for (a) and (b).

[0273] In this case, in the position measuring device 50 according to the first embodiment, if Figure 3As described in (b) of FIG. 5 , both the illumination lights 55 and 56 are incident, thereby generating regular reflection light 551 , scattered light 552 , reflection light 562 , and scattered light 563 .

[0274] Then, part of the scattered light 552 , the reflected light 562 , and part of the light 564 transmitted through the flat plate surface of the flat plate 60 among the scattered light 563 reach the imaging surface of the imaging element 542 and are received.

[0275] Thus, in the position measurement device 250 according to the present embodiment, when the illumination of the illumination area in the alignment mark 601 is not adjusted by the illumination area adjustment unit 537, the image is obtained on the imaging plane of the imaging element 542. Figure 4 Image shown.

[0276] That is, by forming an image on the imaging surface of the imaging element 542 using both the oblique incident illumination method and the back transmission illumination method, the contrast between the rectangles included in the alignment mark 601 and the glass portion 602 outside the rectangles is reduced.

[0277] Furthermore, when an attempt is made to measure the position of the registration mark 601 based on an image having a low contrast, there is a possibility that an erroneous measurement or the like may occur, leading to undesirable results.

[0278] That is, the positioning accuracy of the plate 60 may be reduced due to the erroneous measurement of the position of the alignment mark 601 , and there is a possibility that the overlay (superposition) accuracy may be reduced when the exposure device 1 performs exposure on the plate 60 .

[0279] Therefore, in the position measurement device 250 according to the present embodiment, an illumination region adjustment unit 537 for adjusting the illumination region on the plate surface of the plate 60 is provided near the aperture stop 535 included in the illumination unit 53 .

[0280] Thus, the alignment mark 601 can be illuminated by either the oblique incident illumination method or the back transmission illumination method while using the same light source 531 .

[0281] Therefore, it is possible to obtain an image of the alignment mark 601 with a high contrast on the imaging surface of the imaging element 542 .

[0282] Fig. 9 (a) shows a state in which the illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 537 is illuminated in the position measurement device 250 according to the present embodiment.

[0283] Specifically, in Fig. 9In the structure shown in (a) of FIG. 5 , the illumination area adjustment section 537 is rotated so that the illumination light from the illumination section 53 directly enters the alignment mark 601 , thereby adjusting the illumination area on the flat surface of the flat plate 60 .

[0284] That is, the illumination area adjustment unit 537 does not generate the illumination light 56 ​​incident on the glass portion 602 around the alignment mark 601 , but generates only the illumination light 55 directly incident on the alignment mark 601 , thereby illuminating the illumination area.

[0285] In this case, by selecting the above-mentioned oblique incident illumination method, it is possible to reduce the reflected light 562 and the scattered light 563 that illuminate the alignment mark 601 from below.

[0286] Therefore, scattered light 552 generated by scattering near the ends of each rectangle included in the alignment mark 601 reaches the imaging surface of the imaging element 542 and is received, so that only the ends of each rectangle are bright, as shown in FIG. Fig.11 (b) is an image with higher contrast.

[0287] Fig. 9 (b) shows a state where another illumination region on the flat plate surface of the flat plate 60 adjusted by the illumination region adjustment unit 537 is illuminated in the position measurement device 250 according to the present embodiment.

[0288] Specifically, in Fig. 9 In the structure shown in (b), the illumination area adjustment unit 537 is rotated so that the illumination light from the illumination unit 53 is incident on the glass unit 602 around the alignment mark 601, thereby adjusting the illumination area on the flat surface of the flat plate 60.

[0289] That is, the illumination area adjustment unit 537 does not generate the illumination light 55 that directly enters the alignment mark 601 , but generates only the illumination light 56 ​​that enters the glass portion 602 around the alignment mark 601 , thereby illuminating the illumination area.

[0290] In this case, by selecting the above-mentioned back transmission lighting method, the illumination light 55 that illuminates the alignment mark 601 from above can be reduced.

[0291] Therefore, the reflected light 562 generated on the placement surface of the flat plate 60 in the flat plate stage 70 and the light 564 transmitted through the flat plate surface of the flat plate 60 among the scattered light 563 reach the imaging surface of the imaging element 542 and are received.

[0292] Thus, only the area outside the rectangles of the alignment mark 601 is bright, as shown in FIG. Fig.11 (c) is an image with higher contrast.

[0293] In the position measuring device 250 according to the present embodiment, the illumination area on the flat surface can be switched so that the illumination light is incident only on the alignment mark 601 or the illumination light is incident only on the glass portion 602 around the alignment mark 601 as described above.

[0294] That is, by using the same light source 531 to illuminate the alignment mark 601 in an illumination method selected from the oblique incident illumination method or the back transmission illumination method, an image of the alignment mark 601 with a high contrast can be obtained.

[0295] As described above, in the position measuring device 250 according to the present embodiment, by providing the illumination region adjusting portion 537 as a reflecting portion that reflects illumination light in the illumination portion 53 , it is possible to adjust the illumination region on the plate surface of the plate 60 .

[0296] Thus, by illuminating the alignment mark 601 with the illumination method selected from the oblique incident illumination method and the back surface transmission illumination method, it is possible to obtain an image of the alignment mark 601 with a high contrast.

[0297] Furthermore, in the position measuring device 250 according to this embodiment, the light from the light source 531 can be completely incident on the flat surface of the flat plate 60 without partially shielding the light, so that a wider illumination area can be illuminated with higher illumination efficiency than the position measuring device 50 according to the first embodiment.

[0298] In addition, in the position measurement device 250 according to the present embodiment, the illumination region adjustment unit 537 changes the reflection angle of the illumination light, thereby changing the irradiation position of the illumination light on the flat plate surface of the flat plate 60 .

[0299] Therefore, the illumination area can be adjusted at a higher speed than the position measurement device 50 according to the first embodiment and the position measurement device 150 according to the second embodiment.

[0300] In addition, the position measuring device 250 according to the present embodiment may further include the illumination region adjusting unit 534 in the position measuring device 50 according to the first embodiment and the illumination region adjusting unit 536 in the position measuring device 150 according to the second embodiment.

[0301] That is, in addition to arranging the illumination area adjustment section 537 near the aperture stop 535 , the illumination area adjustment section 534 and the illumination area adjustment section 536 may be arranged near the field stop 533 .

[0302] As mentioned above, although the preferred embodiments have been described, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist of the invention.

[0303] [Production method]

[0304] The method for manufacturing an article according to the present embodiment includes a step of exposing a substrate such as a wafer or a glass substrate coated with a photosensitizer using an exposure device 1 including the position measuring device according to any one of the first to third embodiments.

[0305] In addition, the article includes a semiconductor integrated circuit (IC) element, a liquid crystal display element, a micro-electromechanical system (MEMS), and the like.

[0306] The method for manufacturing the article according to the present embodiment includes a step of developing the exposed substrate (photosensitive agent) and other known steps of processing the developed substrate.

[0307] In addition, the other well-known processes include etching, photosensitive agent stripping, dicing, bonding, packaging, etc.

[0308] According to the method for manufacturing an article according to the present embodiment, it is possible to manufacture an article with higher quality than before.

[0309] (Explanation of symbols)

[0310] 50, 150, 250: position measuring device (camera device); 53: lighting unit; 54: camera unit; 60: flat plate (object); 70: flat plate mounting platform (mounting platform); 534, 536, 537: lighting area adjustment unit.

Claims

1. A camera device, characterized in that: have: an illumination unit for causing illumination light to be incident on an object, the illumination unit including an illumination region adjustment unit capable of performing a first adjustment and a second adjustment, wherein the illumination region for illuminating the object with the illumination light is adjusted in such a manner that the illumination light including light of a predetermined wavelength is incident on a first region of a first region and a second region of the object in large amounts, and the illumination region is adjusted in such a manner that the illumination light is incident on a second region of the first region and the second region in large amounts; An imaging unit for acquiring an image of the object by receiving light from the object; as well as The mounting table has a mounting surface on which the object is mounted and which reflects the light of the predetermined wavelength.

2. The camera device according to claim 1, characterized in that The object includes a first portion that scatters incident light of the predetermined wavelength, The first region includes at least a portion of the first portion.

3. The imaging device according to claim 2, wherein: The imaging unit acquires the image of the object by receiving the light of the predetermined wavelength scattered by the first portion during the first adjustment.

4. The camera device according to claim 2, characterized in that: The imaging unit includes: an imaging element for receiving light from the object; and an imaging optical system for guiding the light from the object to the imaging element. The illumination unit causes the illumination light to be incident on the object at an incident angle equal to or greater than a numerical aperture of the imaging optical system in the first adjustment.

5. The camera device according to claim 2, characterized in that: The object includes a second portion that transmits incident light of the predetermined wavelength, The second region includes at least a portion of the second portion.

6. The imaging device according to claim 5, characterized in that: The imaging unit receives the light of the predetermined wavelength that has passed through the second portion in the second adjustment, reflected by the placement surface, and then passed through the second portion, thereby acquiring the image of the object.

7. The camera device according to claim 1, characterized in that: The illumination region adjustment unit includes a light shielding unit that shields a portion of the illumination light.

8. The imaging device according to claim 7, wherein: The illumination unit includes a field aperture that is arranged at a position optically conjugate with the object and limits the beam diameter of the illumination light. The light shielding section is disposed closest to the field stop included in the optical element of the illumination section.

9. The camera device according to claim 7, characterized in that: The illumination area adjustment unit adjusts the illumination area by rotating the light shielding unit around the optical axis of the illumination unit, displacing the light shielding unit in a predetermined direction perpendicular to the optical axis of the illumination unit, or replacing the light shielding unit with another light shielding unit.

10. The camera device according to claim 1, characterized in that: The illumination region adjustment section includes a transmission section that transmits the illumination light so as to shift the optical axis of the illumination section in a predetermined direction perpendicular to the optical axis of the illumination section.

11. The imaging device according to claim 10, wherein: The illumination unit includes a field aperture that is arranged at a position optically conjugate with the object and limits the beam diameter of the illumination light. The transmission section is disposed closest to the field stop included in the optical element of the illumination section.

12. The imaging device according to claim 10, wherein: The illumination area adjustment unit adjusts the illumination area by rotating the transmission unit around an axis that is perpendicular to the predetermined direction and the optical axis of the illumination unit.

13. The camera device according to claim 1, characterized in that: The illumination area adjustment unit includes a reflection unit that reflects the illumination light.

14. The imaging device according to claim 13, wherein: The illumination unit includes an aperture stop for adjusting the light quantity of the illumination light. The reflecting section is arranged closest to the aperture stop included in the optical element of the illuminating section.

15. The imaging device according to claim 13, wherein: The illumination area adjustment unit adjusts the illumination area by adjusting an angle of a reflection surface of the reflection unit.

16. The imaging device according to claim 1, wherein: The illumination unit includes: a light source for emitting the illumination light; and an illumination optical system for guiding the illumination light from the light source to the object. The illumination unit is configured to be able to adjust at least one of an incident angle of the illumination light on the object, a numerical aperture of the illumination optical system, a wavelength of the illumination light, a light amount of the illumination light, and polarization of the illumination light.

17. The camera device according to claim 1, characterized in that: The number of the light sources included in the illumination unit and emitting the illumination light is one.

18. The camera device according to claim 1, characterized in that: The object has a predetermined surface including the first region and the second region, The optical axis of the illumination unit is non-perpendicular and non-parallel to the predetermined surface.

19. The imaging device according to claim 18, wherein: The optical axis of the imaging unit is perpendicular to the predetermined surface.

20. The imaging device according to claim 1, wherein: A control unit is provided for causing the imaging unit to acquire the image in one of the first adjustment and the second adjustment selected, or causing the imaging unit to acquire the image in both the first adjustment and the second adjustment, based on an input parameter.

21. The imaging device according to claim 20, characterized in that: The input parameters include the material of the object.

22. An exposure device for projecting an image of a pattern of an original plate onto a substrate and exposing the substrate, characterized in that: have: A projection optical system for guiding the exposure light passing through the original plate to the substrate; The imaging device according to any one of claims 1 to 21, which acquires an image of the substrate on which the alignment mark is formed; as well as The control unit obtains the position of the alignment mark in a plane perpendicular to the optical axis of the projection optical system from the image of the alignment mark included in the image of the substrate obtained by the imaging device, and adjusts the position of the stage according to the obtained position.

23. A method for manufacturing an article, characterized in that: include: A step of exposing a substrate using the exposure device according to claim 22; as well as A step of developing the exposed substrate.

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