JP2011082468A - Exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure device that detects an amount of a relative position shift between a position where a projection optical system projects an exposure pattern and a detection position of a position detection optical system without moving the position detection optical system on a reverse surface side, and performs exposure with high precision using the amount of the position shift. <P>SOLUTION: The exposure device 1 includes a stage 9 where a substrate 7 is mounted, the projection optical system 4 which is disposed on a top-surface side of the substrate 7 and projects the pattern on the substrate 7, a top-surface position detection optical system 80 for detecting the projection position of the pattern by the projection optical system 4, a top-surface detection illumination optical system 70, a reverse-surface position detection optical system 6 for detecting the position of a positioning mark on the reverse-surface side of the substrate 7, an index plate 10 provided on the stage 9, and a control unit 11 which calculates the amount of the relative position shift between the projection position of the pattern by the projection optical system 4 and the detection position on the reverse-surface side by the reverse-surface position detection optical system 6. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an exposure apparatus.

  Conventionally, when an electric circuit element is manufactured by applying a photoresist on a substrate and performing exposure, development, and etching processes, some electric circuit elements such as a thyristor have a structure on both sides of the substrate. It was necessary to create an element by performing the above steps. In order to perform processing on both surfaces with high accuracy, an exposure apparatus has been proposed that performs alignment by detecting an alignment mark provided on the back surface of the substrate (see, for example, Patent Document 1). In addition, recently, MEMS (Micro Electro Mechanical Systems) elements and the like have been created using a semiconductor process, and thus the demand for processing from such a back surface is increasing. In this case, more precise processing technology is required, but it is necessary to determine the relative relationship between the position where the projection optical system projects the pattern and the position where the position detection optical system detects the alignment mark. Has been proposed (see, for example, Patent Document 2). The invention described in Patent Document 2 is an exposure method using a reticle (or photomask). For alignment of the substrate before exposure, the projection is first performed with the substrate retracted from the projection optical system. A reticle alignment mark provided on the reticle is projected by an optical system, and the projection position is detected by a position detection optical system on the back side. At this time, the lens of the position detection optical system is moved to remove the influence of the thickness of the substrate. In addition, a technique has been proposed in which a spatial light modulation element such as a DMD (Digital Mirror Device) is used in place of the reticle and the projection magnification is variable (see, for example, Patent Document 3).

JP-A-62-254423 Japanese Patent Publication No. 6-50714 Japanese Patent No. 4195915

  However, in these conventional techniques, the optical axis may be shifted by moving the lens of the position detection optical system, or the movement direction may not completely coincide with the optical axis of the projection optical system. There has been a problem that the position detected by the position detection optical system is displaced.

  The present invention has been made in view of such a problem, and the position where the projection optical system projects the image of the exposure pattern without moving the position detection optical system on the back side, and the position detection optical system on the back side. An object of the present invention is to provide an exposure apparatus capable of detecting a relative positional shift amount with respect to a detection position of an alignment mark by performing high-precision exposure.

  In order to solve the above problems, an exposure apparatus according to the present invention includes a stage having a holder on which a substrate is placed, a pattern generation unit that generates a desired pattern, a projection optical system that projects the pattern onto the substrate, A surface position detection optical system that detects the pattern projected by the projection optical system is disposed on the front side of the substrate on which the pattern is projected, and an alignment mark that is disposed on the back side of the substrate and formed on the back surface of the substrate. The position of the back surface position detection optical system to be detected, the index plate provided on the stage, on which the alignment mark for coordinate correction that can be observed from both the front surface position detection optical system and the back surface position detection optical system is formed, and the position of the holder The position measurement unit to be detected and the pattern generated by the pattern generation unit are projected by the projection optical system, and the projected pattern and the alignment mark for coordinate correction are substantially matched. The position of the holder when it is detected by the surface position detection optical system is read from the position measurement unit, and the position of the holder when the alignment mark for coordinate correction of the index plate is detected by the back surface position detection optical system is read from the position measurement unit. And a control unit that calculates a relative shift amount between the front surface position detection optical system and the rear surface position detection optical system as a coordinate correction value from these positions.

  Such an exposure apparatus has a stage drive unit that moves the stage in the optical axis direction, and the control unit uses the front surface position detection optical system and the back surface position detection optical system to position the coordinate correction alignment mark on the index plate. When detecting, it is preferable that the stage is moved in the optical axis direction by the stage driving unit so that the focal position of each optical system substantially coincides with the alignment mark for coordinate correction.

  Further, in such an exposure apparatus, the projection optical system is configured so that the projection magnification can be switched, and further includes a projection magnification switching detection unit that detects switching of the projection magnification of the projection optical system, and the control unit detects the projection magnification switching. If it is detected that the projection magnification has been switched by the unit, and the projection magnification is switched since the last time the back surface position was detected when the back surface position was detected, the front surface position It is preferable that the detection optical system and the back surface position detection optical system detect a coordinate correction alignment mark on the index plate, read the position of the holder from the position measurement unit, and calculate a coordinate correction value.

  When the exposure apparatus according to the present invention is configured as described above, the projection optical system projects the image of the exposure pattern without moving the position detection optical system on the back side of the substrate even when the projection magnification is switched. Further, it is possible to detect the amount of positional deviation relative to the detection position of the alignment mark by the position detection optical system on the back surface side, and perform exposure by the exposure apparatus with high accuracy.

It is the schematic which shows the structure of the exposure apparatus which concerns on this embodiment. It is the schematic which shows the parameter | index board which formed the cross extraction pattern in the center. It is the schematic which shows the pattern image of the parameter | index plate detected with the two-dimensional image sensor of the surface position detection optical system, and the cross pattern black pattern image.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present specification, the surface direction on the exposure side of the substrate is referred to as “front side” through the substrate, and the surface direction opposite to the exposure side is referred to as “back side”. First, the configuration of the exposure apparatus 1 according to the present embodiment will be described with reference to FIG. This exposure apparatus 1 is a maskless exposure apparatus that projects an image (exposure pattern) from a DMD element onto a substrate 7, and as shown in FIG. 1, an illumination optical system 2 that irradiates illumination light, and this illumination A DMD element 3 as a pattern generation unit that spatially modulates illumination light from the optical system 2 to generate a plurality of images (exposure patterns), and projection optics that projects the exposure pattern from the DMD element 3 onto the substrate 7 A system 4, an autofocus detection optical system 5 that is incorporated in the projection optical system 4 and adjusts so that the image of the exposure pattern from the DMD element 3 is focused on the surface of the substrate 7, and the exposure pattern on the surface side A surface position detection optical system 80 for detecting the projection position, the position of the index plate, and the alignment mark on the substrate, and a wave that does not sensitize the photoresist applied on the substrate 7 when detecting the projection position. A stage 9 including a front surface detection illumination optical system 70 for illuminating with a back surface, a back surface position detection optical system 6 for detecting the position of the alignment mark on the back surface side of the substrate 7, and a holder 8 for mounting the substrate 7. The operation of the DMD element 3 and the stage 9 is controlled by detection results from the index plate 10 provided on the stage 9, the autofocus detection optical system 5, the front surface position detection optical system 80, and the back surface position detection optical system 6. The control unit 11 and the projection optical system 4 are configured to include a second projection optical system 40 having different projection magnifications.

  The DMD element 3 includes a plurality of micromirrors (not shown) that can change the reflection angle. Each micromirror of the DMD element 3 is driven by the control unit 11, and by changing the reflection angle of the reflection surface, it is possible to arbitrarily select whether the reflected light is guided to the projection optical system 4 or not, Various shapes of exposure patterns can be generated.

  The illumination optical system 2 condenses the illumination light from the exposure light source 21 that emits a wavelength for exposing the photoresist coated on the substrate 7 made of a mercury lamp, LED, etc., and irradiates the DMD element 3 with the illumination light from the exposure light source 21. And a condenser lens 22 to be used. The projection optical system 4 also includes a second objective lens 41 that converts the exposure pattern (exposure light) generated by the DMD element 3 into substantially parallel light, and a first objective that projects the substantially parallel light onto the substrate 7. And a lens 42. Here, the meaning of substantially parallel means that light emitted from one point on the DMD element 3 becomes substantially parallel, and light emitted from another point on the DMD element 3 also becomes substantially parallel. However, the angle of light of both is different.

  Further, the exposure apparatus 1 of the present embodiment enables switching between the projection optical system 4 and the second projection optical system 40 by a switching mechanism (not shown). Thus, by switching the projection optical system 4 to the second projection optical system 40, the projection magnification between the DMD element 3 and the substrate 7 can be changed. The exposure apparatus 1 is configured so that the projection magnification switching detection unit 14 can detect that the projection optical system 4 and the projection optical diameter 40 have been switched.

  The surface detection illumination optical system 70 is a surface position detection light source 71 that emits surface position detection light (hereinafter referred to as “surface position detection light”) (consisting of an LED, a halogen lamp, a fiber light source, or the like). A condensing lens 72 that condenses the surface position detection light from the surface position detection light source 71, an aperture stop 73, a field stop 74, and a first relay that converts the surface position detection light into substantially parallel light and relays it. The lens 75 and the second relay lens 76, and a half mirror 77 arranged on the optical path of the projection optical system 4 and reflecting the surface position detection light toward the substrate 7, have a wavelength that does not expose the photoresist on the substrate 7. The substrate 7 is illuminated with the surface position detection light.

  The surface position detection optical system 80 is disposed on the optical path of the projection optical system 4 and reflects the reflected light reflected from the substrate 7 by the irradiation of the surface position detection light, and the reflection reflected by the half mirror 83. An imaging lens 82 that forms an image of light and a two-dimensional imaging element 81 that detects the image are formed. The first objective lens 42 and the imaging lens 82 cooperate to two-dimensionally image the surface of the substrate 7. The surface of the substrate 7 or the indicator plate 10 is observed by connecting the element 81 in a conjugate manner. In the two-dimensional image sensor 81, the surface image of the substrate 7 is photoelectrically converted, and the alignment mark is recognized by image processing.

  The autofocus detection optical system 5 emits a point light source 51 that emits focus detection light having a wavelength that does not expose the photoresist coated on the substrate 7 (hereinafter, referred to as “focus detection light”), and the point light source 51. A collimator lens 52 for converting the focus detection light from the light into a substantially parallel light, a light-shielding stop 53 that blocks half of the pupil of the focus detection light transmitted through the collimator lens 52, and the substantially parallel focus detection light transmitted. A half mirror 54 that further reflects the reflected light reflected by the substrate 7, and a dichroic mirror 55 that is disposed on the optical path of the projection optical system 4, reflects the focus detection light and the reflected light, and transmits the exposure light; An imaging lens 56 for imaging the reflected light reflected by the dichroic mirror 55 and the half mirror 54, and a linear sensor for receiving the image. And a 57.

  The holder 8 on which the substrate 7 is placed penetrates in a vertical direction (a direction substantially parallel to the optical axes of the projection optical system 4 and the back surface position detection optical system 6; hereinafter, this vertical direction is referred to as a “Z axis”). A through hole 8a and a through hole 8b are formed. The through hole 8 a is an opening for observing the alignment mark formed on the back surface of the substrate 7. For example, a plurality of alignment marks such as cross marks are formed on the back surface of the substrate 7, and these alignment marks are connected to the back surface via a plurality of through holes 8 a formed corresponding to the alignment marks. The position detection optical system 6 detects. An indicator plate 10 is attached to the through hole 8b. As will be described later, the index plate 10 has a relative relationship between the exposure pattern projection position of the projection optical system 4 detected using the front surface position detection optical system 80 and the detection position of the alignment mark by the back surface position detection optical system 6. It is provided for detecting a large amount of positional deviation. The through hole 8b (index plate 10) is formed at a position where the substrate 7 placed on the holder 8 does not block the through hole 8b. The stage 9 can be moved in the horizontal direction and the vertical direction (up and down direction) by a stage driving unit 13 controlled by the control unit 11. Note that a position measuring unit 12 including an interferometer or a linear encoder is attached to the stage 9, and the position (coordinates) of the holder 8 is monitored by the control unit 11. Hereinafter, in the horizontal direction, the horizontal direction in FIG. 1 is taken as the X axis, and the direction intersecting this (the vertical direction on the paper) is taken as the Y axis.

  The back surface position detection optical system 6 is disposed on the back surface side facing the projection optical system 4 with the holder 8 interposed therebetween, that is, below the holder 8. The back surface position detection optical system 6 emits back surface position detection light (hereinafter referred to as “back surface position detection light”), and a back surface position detection light from the back surface position detection light source 61. The condenser lens 62 for condensing the light, the half mirror 63 for reflecting the back surface position detection light collected by the condenser lens 62 toward the substrate 7, and the back surface position detection light reflected by the half mirror 63 are condensed. An objective lens 64 that illuminates the back surface of the substrate 7, an imaging lens 65 that forms an image of reflected light that is reflected by the back surface of the substrate 7, collected again by the objective lens 64, and transmitted through the half mirror 63, and The image sensor 66 to detect and the field stop 67 are comprised.

  In the exposure apparatus 1 configured as described above, illumination light (exposure light) emitted from the exposure light source 21 of the illumination optical system 2 is applied to the DMD element 3 via the condenser lens 22. At this time, the control unit 11 controls the reflection angles of all the micromirrors corresponding to the pixels of the DMD element 3 in response to a signal of a pattern generator (not shown) built in the control unit 11. With this control, each micromirror of the DMD element 3 can select whether or not to guide the illumination light to the projection optical system 4, and a desired exposure pattern can be generated. The exposure pattern generated by the DMD element 3 is projected onto the substrate 7 by the projection optical system 4. At this time, based on the focus signal from the autofocus detection optical system 5 incorporated in the projection optical system 4, the stage 9 is moved up and down via the stage drive unit 13 under the control of the control unit 11, The exposure pattern is projected so as to be focused on the surface of the substrate 7. Then, exposure of the substrate 7 is performed by projection of the exposure pattern.

  Here, the operation of the autofocus detection optical system 5 will be described. First, focus detection light emitted from the point light source 51 is converted into substantially parallel light by the collimator lens 52. As described above, the substantially parallel focus detection light is narrowed down by blocking about half of the pupil by the light-shielding diaphragm 53, then passes through the half mirror 54, and enters the dichroic mirror 55. The dichroic mirror 55 Thus, the light is reflected in the direction of the substrate 7 and irradiated onto the substrate 7 through the first objective lens 42 of the projection optical system 4. Then, the reflected light reflected by the substrate 7 is condensed again by the first objective lens 42 of the projection optical system 4, then reflected by the dichroic mirror 55 and guided to the autofocus detection optical system 5. The reflected light is further reflected by the half mirror 54 and imaged on the linear sensor 57 by the imaging lens 56. Thus, the autofocus detection optical system 5 is a so-called pupil half-hidden focus detection optical system. Then, based on the image obtained by the linear sensor 57, the vertical displacement of the substrate 7 with respect to the in-focus position of the projection optical system 4 is detected. Based on the signal, the control unit 11 passes the stage drive unit 13 through the stage drive unit 13. The stage 9 is moved in the optical axis direction (vertical direction) to focus the exposure pattern from the DMD element 3 on the surface of the substrate 7.

  On the other hand, in the back surface position detection optical system 6, the position detection light emitted from the back surface position detection light source 61 illuminates the field stop 67, and a through hole provided in the holder 8 by the condenser lens 62, the half mirror 63, and the objective lens 64. The back surface of the substrate 7 is illuminated through 8a. At this time, the field stop 67 and the back surface of the substrate 7 are configured to be substantially conjugate. A plurality of alignment marks are formed on the back surface of the substrate 7 as described above. The position detection light reflected by the back surface of the substrate 7 is condensed again by the objective lens 64 to become substantially parallel light, passes through the half mirror 63, and then forms an image on the image sensor 66 by the imaging lens 65. In this image sensor 66, the back image of the substrate 7 is photoelectrically converted, and the alignment mark is recognized by image processing.

  In the back surface position detection optical system 6, the control unit 11 stores in advance the stage coordinates of the index plate 10 serving as the alignment reference point (for example, an HDD or a flash memory provided in the control unit 11). Stored in the storage unit). The stage 9 is moved via the stage drive unit 13 under the control of the control unit 11 so that the reference point and the centers of the plurality of alignment marks recognized by the image sensor 66 are sequentially matched. And the control part 11 calculates the position in the horizontal surface on the coordinate in the stage 9 of the board | substrate 7, and the rotation amount in a horizontal surface by reading the coordinate of the stage 9 in that case from the position measurement part 12. FIG. Based on the position and rotation amount of the substrate 7 calculated in this way, the stage 9 is moved to move the substrate 7 to a predetermined exposure position, and exposure processing is performed. The processing by the back surface position detection optical system 6 is executed, for example, after the substrate 7 is set on the holder 8 and before the exposure processing.

  By the way, even when the substrate 7 is arranged at an accurate exposure position as described above, the relative position between the projection position of the exposure pattern by the projection optical system 4 and the detection position of the alignment mark by the back surface position detection optical system 6. If there is a deviation in the relationship, high-precision machining cannot be performed unless the positional deviation is accurately measured and coordinate correction is performed. Therefore, a mechanism and a method for measuring this positional deviation amount using the index plate 10 will be described below.

  First, as shown in FIG. 2, the indicator plate 10 is formed by depositing Cr on the surface of transparent glass (100 portion in FIG. 2) and forming a cross-shaped pattern 101 in the center as a coordinate correction alignment mark. Use. Then, the control unit 11 moves the stage 9 in the X and Y axis directions via the stage driving unit 13 so that the index plate 10 is positioned at the projection position of the projection optical system 4, and further, the projection optical system 4 and the surface The height (Z axis) of the stage 9 is adjusted so that the focus of the position detection optical system 80 coincides with the index plate 10. Needless to say, optical adjustment is made in advance so that the focal planes of the projection optical system 4 and the surface position detection optical system 80 are the same. Therefore, the pattern 101 formed on the index plate 10 can be observed by the surface position detection optical system 80.

  Next, the DMD element 3 generates an elongated cross-shaped black pattern (exposure pattern) substantially at the center of the DMD element 3 and projects it onto the index plate 10. At this time, when the index plate 10 is observed with the surface position detection optical system 80, as shown in FIG. 3, the image 10 'detected by the two-dimensional imaging device 81 is light-irradiated in the Cr deposition portion (100 in FIG. 2). Reflected and bright (100 ′ portion in FIG. 3), an image 101 ′ of a cross-shaped pattern (101 in FIG. 2) on which Cr is not deposited and an image 102 of a cross-shaped black pattern generated by the DMD element 3 Will look black. Here, the stage 9 is moved in the X and Y axis directions via the stage drive unit 13 so that the centers of the cross-cut pattern image 101 ′ and the black pattern image 102 coincide. The control unit 11 reads the stage coordinates at this time from the position measurement unit 12 and stores them in a storage unit such as a memory as coordinates A.

  Further, the control unit 11 moves the stage 9 in the X and Y axis directions via the stage drive unit 13 so that the index plate 10 is positioned at the observation position of the back surface position detection optical system 6, and the back surface position detection optical system 6. The indicator plate 10 is observed using. At this time, since the focal plane of the back surface position detection optical system 6 is shifted by the thickness of the substrate 7 with respect to the focal plane of the front surface position detection optical system 80, the pattern 101 on the index plate 10 is in focus. Not. Therefore, the height (Z axis) of the stage 9 is moved via the stage drive unit 13 so that the pattern 101 on the indicator plate 10 can be clearly observed. At this time, the back surface position detection optical system 6 changes the optical path length by observing the pattern 101 through the glass having the thickness of the index plate 10. It does not match the thickness. If the thickness of the index plate 10 is large, or if the NA of the back surface position detection optical system 6 is large, spherical aberration occurs and the pattern 101 cannot be clearly observed. 3 or less and the thickness is 1 mm or less. In addition, the orthogonality of the XYZ axes of the stage 9 is sufficiently secured, and the movement in the X and Y axis directions when the Z axis is moved is small enough to be ignored.

  Next, when the image of the pattern 101 of the index plate 10 is observed with the back surface position detection optical system 6, the optical axes of the front surface position detection optical system 80 and the back surface position detection optical system 6 do not exactly coincide with each other. The center of the image 101 is shifted from the center of the image sensor 66. Therefore, the stage 9 is moved in the X and Y axis directions via the stage drive unit 13 so that the center of the image of the pattern 101 is accurately positioned at the center of the image sensor 66. The control unit 11 reads the stage coordinates at this time from the position measurement unit 12 and stores them in the storage unit as coordinates B.

  The difference between the projection position coordinate A of the projection optical system 4 detected by the front surface position detection optical system 80 and the coordinate position B of the pattern image detection position of the index plate 10 by the back surface position detection optical system 6 is defined as a coordinate correction value Δ. . In this way, the control unit 11 compares the coordinates A and the coordinates B, thereby projecting the exposure pattern onto the front surface side by the projection optical system 4 with respect to the position coordinates detected by the back surface position detection optical system 6. A coordinate correction value Δ representing how much the position coordinates are shifted can be calculated and stored. Therefore, at the time of actual exposure, the projection optical system 4 accurately observes the surface side of the substrate 7 while observing the alignment mark on the back side of the substrate 7 with the back surface position detection optical system 6 using the coordinate correction value Δ. It is possible to project and expose a desired exposure pattern at various positions.

  In the present embodiment, the black pattern image 102 generated by the DMD element 3 is projected on the cross-cut pattern image 101 'on the index plate 10 so as to be centered. However, the present invention is not limited to this. For example, a cross pattern image (black pattern image) 102 is projected onto a position where there is no mark on the index plate 10 or on a separate reflector, and the center coordinates of the pattern on the two-dimensional image sensor are stored. The cross pattern image 102 may be erased, and the center of the cross pattern image 101 'on the index may be matched with the stored center coordinates, and the stage coordinates at that time may be A. Also, the pattern is not limited to a crosshair. That is, it is only necessary to store the stage coordinates when the projection pattern and the center of the pattern on the index coincide with each other, and it does not limit the simultaneity of pattern observation or the pattern shape.

  Next, switching of the projection magnification and a method of detecting the positional deviation amount at that time will be described. In the present embodiment, as described above, the projection optical system 4 has the second projection optical system 40 having a projection magnification different from that of the projection optical system 4, and the projection optical systems 4 and 40 are switched by a switching mechanism (not shown) to set the projection magnification. It is configured to be changed. Since the coordinate correction value Δ may change when the projection optical systems 4 and 40 are switched in this way, the control unit 11 determines that the projection optical diameters 4 and 40 are switched by the projection magnification switching detection unit 14. Preferably, the coordinate correction value Δ is calculated and stored independently at each projection magnification.

  In addition, an error of the mechanical mechanism is unavoidable in this magnification switching mechanism, and when the projection magnification is switched, the position of the exposure pattern projected on the substrate 7 may be displaced. Therefore, every time the switching mechanism is operated, the above-mentioned coordinate A may change randomly. Even if the switching mechanism does not operate, both the coordinates A and B may change due to external vibrations and temperature changes. Therefore, in order to accurately expose the surface of the substrate 7 by the projection optical systems 4 and 40, the control unit 11 periodically uses the front surface position detection optical system 80 and the back surface position detection optical system 6 to set the coordinate correction value Δ. Alternatively, it is preferably calculated when the projection magnification is switched. At least when the back surface position is detected, the projection magnification switching detection unit 14 detects that the magnification has been switched since the previous back surface position was detected. In this case, it is preferable to calculate again.

  In the present embodiment, as the magnification switching mechanism, the projection optical system 4 including the set of the first objective lens 42 and the second objective lens 41 is changed from the set of the first objective lens 44 and the second objective lens 43. However, the present invention is not limited to this, and it is not always necessary to switch the projection optical systems 4 and 40 as a whole. For example, only the first objective lens 42 may be switched to an objective lens having a different focal length (for example, the first objective lens 44), or only the second objective lens 41 may have an objective lens having a different focal length (for example, a second objective lens). It is good also as a structure switched to the objective lens 43). The projection optical systems 4 and 40 may be zoom lenses. However, from the viewpoint of ease of aberration correction, a method of switching the entire projection optical systems 4 and 40 as in the present embodiment is preferable.

  In the above description, the example in which the magnification switching mechanism and the positional deviation detection mechanism are applied to the so-called maskless exposure apparatus 1 using the DMD element 3 has been described. However, it is applied to an exposure apparatus using a reticle. You can also. In this case, by detecting the reticle alignment mark with the back surface position detection optical system 6, the coordinates of the position where the exposure pattern is projected can be read as the coordinates of the stage 9, and the same procedure as the above-described alignment process is performed. The coordinate correction value Δ is detected from the coordinate A detected by the front surface position detection optical system 80 and the coordinate B detected by the back surface position detection optical system 6, and exposure processing can be performed using this coordinate correction value Δ. It is. Furthermore, these mechanisms can be applied to position adjustment (alignment) in three-dimensional mounting.

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 3 DMD element (pattern production | generation part) 4 Projection optical system 6 Back surface position detection optical system 7 Substrate 8 Holder 9 Stage 10 Index plate 11 Control part 12 Position measurement part 13 Stage drive part 14 Projection magnification change detection part 70 Surface position Detection optical system

Claims (3)

A stage having a holder for placing a substrate;
A pattern generation unit for generating a desired pattern;
A projection optical system for projecting the pattern onto the substrate;
A surface position detection optical system that is disposed on the surface side of the substrate on which the pattern is projected and detects the pattern projected by the projection optical system;
A back surface position detection optical system that is disposed on the back surface side of the substrate and detects an alignment mark formed on the back surface of the substrate;
An indicator plate provided on the stage, on which an alignment mark for coordinate correction that can be observed from both the front surface position detection optical system and the back surface position detection optical system is formed,
A position measuring unit for detecting the position of the holder;
The pattern generated by the pattern generation unit is projected by the projection optical system, and the surface position detection optical system detects that the projected pattern and the alignment mark for coordinate correction are substantially matched. Read the position of the holder from the position measuring unit, read the position of the holder from the position measuring unit when the back surface position detection optical system detects the coordinate correction alignment mark of the index plate, An exposure apparatus comprising: a control unit that calculates a relative shift amount between the front surface position detection optical system and the back surface position detection optical system as a coordinate correction value from the position. A stage drive unit for moving the stage in the direction of the optical axis;
The controller is
When detecting the coordinate correction alignment mark on the indicator plate by the front surface position detection optical system and the back surface position detection optical system, the focal position of each optical system substantially matches the coordinate correction alignment mark. The exposure apparatus according to claim 1, wherein the stage driving unit is configured to move the stage in an optical axis direction. The projection optical system is configured so that the projection magnification can be switched,
A projection magnification switching detecting unit for detecting switching of the projection magnification of the projection optical system;
The control unit stores that the projection magnification switching detection unit has detected that the projection magnification has been switched, and the projection magnification of the projection magnification from the last time the back surface position was detected when the back surface position was detected. When switching is performed, the front surface position detection optical system and the back surface position detection optical system detect the coordinate correction alignment mark on the index plate and read the position of the holder from the position measurement unit. The exposure apparatus according to claim 1, wherein the exposure apparatus is configured to calculate the coordinate correction value.

Images