WO2000019261A1

WO2000019261A1 - Image formation position adjusting device, exposure system, image formation adjusting method and exposure method

Info

Publication number: WO2000019261A1
Application number: PCT/JP1999/005104
Authority: WO
Inventors: Hiroshi Shirasu
Original assignee: Nikon Corporation
Priority date: 1998-09-25
Filing date: 1999-09-20
Publication date: 2000-04-06
Also published as: JP2010135803A; KR20010089255A; KR100617376B1; AU5653899A; JP4900465B2; TW446829B

Abstract

An image formation position adjusting device (31) provided on an optical axis of an optical system and adapted to properly change and adjust with high accuracy and continuously an image formation position of the projection optical system, comprising first and second optical members (32, 33) consisting of wedge-shaped sheets of glass, disposed facing each other and having tilted surfaces (32b, 33a), wherein a positive pressure groove (33c) supplied with a compressed air from a positive pressure source (P) and a negative pressure groove (33d) vacuum-sucked by a negative pressure source (V) are provided in the tilted surface (32b) of the first optical member (32) to form an air bearing with the first and second optical members (32, 33) facing each other in non-contact condition, and a relative clearance (sheet thickness) between a plane (32a) of light incidence and a plane (33b) of outgoing light can be changed and adjusted by actuating an actuator (35) against an urging force of a coil spring (36) to relatively move the first optical member (32) with respect to the second optical member (33).

Description

Technical Field Image forming position adjusting apparatus, exposure apparatus, image forming position adjusting method and exposure method

The present invention relates to an imaging position adjusting device of an exposure device used for manufacturing a micro device such as a liquid crystal display device or a plasma display device, an exposure device provided with the imaging position adjusting device, an imaging position adjusting method, and an exposure method. About. Background art

In order to manufacture a relatively large liquid crystal panel with a high throughput, a scanning (scanning) projection exposure apparatus is used. This scanning projection exposure apparatus illuminates a mask with a plurality of slit-shaped illumination areas, scans the mask in a direction orthogonal to the arrangement direction of the illumination areas, and scans an exposure area conjugate to the illumination area. This is a device that synchronously scans a photosensitive substrate (glass plate, etc.) coated with a photoresist to project the pattern on the mask at the same size or at a reduced size, and sequentially exposes the photosensitive substrate. . The projection optical system is provided corresponding to each of the plurality of illumination areas.

Here, it is desirable that the surface of the mask (pattern surface) and the surface of the photosensitive substrate (exposure surface) are set at conjugate positions with respect to the projection optical system during exposure, so that the mask and the photosensitive substrate are respectively different. The attitude of the ring device is changed and controlled by the ring device. The leveling device includes a plurality of actuators and the like that are displaced in a direction along the optical axis of the projection optical system. By appropriately operating each of the actuators, the mask and the photosensitive substrate are removed. It shifts in the direction along the optical axis and rotates about two orthogonal axes in a plane orthogonal to the optical axis.

By the way, irregularities are present on the surfaces of the mask and the photosensitive substrate due to the flatness of the mask itself and the bending due to the holding state. Therefore, when viewed locally, the mask and the photosensitive substrate may not be conjugate with respect to the projection optical system.

Therefore, conventionally, the light between the image forming position (image forming plane) of each projection optical system and the surface of the photosensitive substrate is known. In order to reduce the distance along the axis (focus error), the leveling device was used to control the attitude of the photosensitive substrate, etc., so that the average was adjusted to be optimal.

However, even if the leveling device adjusts the position so that it is optimal on average, the focus error at the position corresponding to each projection optical system on the photosensitive substrate is reduced but remains. In some cases, the accuracy and integration of microdevices to be manufactured are limited. The above problems can be alleviated by increasing the precision of the mask, the light-sensitive substrate, and the table that holds them, etc., but this causes problems such as an increase in manufacturing man-hours and costs. Is desired.

Here, the image formation position of the projection optical system can be adjusted according to the plate thickness by installing the parallel plane glass on the optical axis. It is conceivable that the respective images of the respective projection optical systems are formed on the surface of the photosensitive substrate by installing them on the surface of the photosensitive substrate.

However, since the unevenness of the photosensitive substrate and the mask is not uniform, the adjustment of the imaging position of each projection optical system can be changed continuously, that is, it is necessary to be able to change and adjust the thickness of the parallel flat glass continuously. In addition, it is necessary that the change of the plate thickness be adjusted with extremely high accuracy and stably for a long period of time. Disclosure of the invention

Accordingly, an object of the present invention is to provide an image forming position adjusting device capable of continuously changing and adjusting the image forming position of a projection optical system with high accuracy, an exposure apparatus having the image forming position adjusting device, and an image forming position adjusting device. An object of the present invention is to provide a method and an exposure method, and achieve high precision and high integration of a manufactured micro device while suppressing an increase in cost and the like.

According to a first aspect of the present invention, there is provided an image forming position adjusting device for adjusting an image forming position of an optical system, comprising first and second optical members having opposed inclined surfaces and transmitting light of a predetermined wavelength. A non-contact device that causes the opposed inclined surfaces to face each other in a non-contact manner; and a movement that relatively moves the first optical member and the second optical member along a direction that intersects the optical axis of the optical system. An imaging position adjusting device including the device is provided. According to the image forming position adjusting device of the present invention, the first and second optical members having opposed inclined surfaces are moved by the moving device. The relative thickness of the first and second optical members can be changed and adjusted by relative movement. Therefore, by installing this imaging position adjusting device on the optical axis of the projection optical system, it is possible to arbitrarily change and adjust the imaging position of the projection optical system.

Here, although not particularly limited, the non-contact device may be a non-contact type bearing, for example, a device including a gas bearing. By adopting a non-contact device including such a gas bearing, the relative position of the first and second optical members can be finely adjusted without touching each other, and the adjustment of the relative position change is required. The imaging position can be adjusted with high precision and stability with little deterioration over time.

According to a second aspect of the present invention, there is provided an exposure apparatus for exposing a pattern to a substrate by a projection optical system, wherein the exposure apparatus is disposed in the projection optical system, has an opposed inclined surface, and has a predetermined wavelength. A first optical member that transmits light, and a moving device that relatively moves the first optical member and the second optical member along a direction that intersects the optical axis of the projection optical system. An exposure apparatus provided with an imaging position adjusting device is provided. According to this exposure apparatus, since the image forming position adjusting apparatus is provided, the image forming position of the projection optical system can be arbitrarily changed and adjusted, and when the surface of a substrate or the like to be exposed has irregularities. Even if it does, an image can be reliably formed on the surface of the substrate, and a microdevice with high precision and high integration can be manufactured.

According to a third aspect of the present invention, there is provided an image forming position adjusting method for adjusting an image forming position of an optical system, comprising first and second optical members having opposed inclined surfaces and transmitting light of a predetermined wavelength. Is provided in the optical system, and the step of non-contact moving the first optical member and the second optical member along the inclined surface is provided.

According to a fourth aspect of the present invention, there is provided an exposure method for exposing a pattern to a substrate by a projection optical system, comprising a first and a second, which have opposed inclined surfaces and transmit exposure light of a predetermined wavelength. Arranging an optical member in the projection optical system; and relatively moving the first optical member and the second optical member along a direction intersecting the optical axis of the projection optical system. An exposure method is provided. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a main configuration of a scanning projection exposure apparatus according to an embodiment of the present invention,

FIG. 2 is a diagram showing the relationship between the photosensitive substrate and the viewing area according to the embodiment of the present invention,

FIG. 3 is a diagram showing a configuration of a projection optical system according to an embodiment of the present invention,

FIG. 4 is a side view showing the configuration of the imaging position adjusting device according to the embodiment of the present invention,

FIG. 5 is a bottom view of the first optical member of the imaging position adjusting device according to the embodiment of the present invention,

FIG. 6 is a diagram showing an outline of processing according to the embodiment of the present invention,

FIG. 7A is a diagram showing a state of leveling control according to the embodiment of the present invention, and

FIG. 7B is a diagram illustrating a state of the imaging position adjustment control according to the embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 is a diagram showing a main configuration of a scanning projection exposure apparatus according to an embodiment of the present invention, and FIG.

In FIG. 1, 11 is a mask on which a pattern to be transferred is formed, and 12 is a photosensitive substrate such as a glass plate coated with a photosensitive material (photoresist). The mask 11 and the photosensitive substrate 12 are arranged to face each other with a plurality of projection optical systems 13 (five in this embodiment) interposed therebetween. Here, the direction along the optical axis of the projection optical system 13 that is substantially perpendicular to the mask 11 and the photosensitive substrate 12 is defined as the Z direction (Z axis), and the plane perpendicular to the Z direction is shown in FIG. The direction parallel to is defined as the X direction (X axis), and the direction perpendicular to the paper plane in FIG. 1 perpendicular to the Z direction and the X direction is defined as the Y direction (Y axis). An illumination optical system 14 is arranged on the side of the mask 11 opposite to the projection optical system 13. In the illumination optical system 14, although not shown, the illumination light emitted from a plurality of light sources, such as an ultra-high pressure mercury lamp, is once gathered by a light guide or the like and then uniformly distributed and emitted. You. The light emitted from the light guide is converted into a light beam having a uniform illuminance distribution by a fly eye integrator, and shaped into a slit by a blind having a slit-shaped (rectangular) opening. The light beam that has passed through the blind enters the condenser lens, By forming an image of this light beam on the mask 11, the mask 11 is illuminated by a plurality of slit-like illumination regions. Reference numeral 15 denotes an alignment microscope which is disposed at a position between the mask 11 and the light emitting portion of the illumination optical system 14 so as to be able to move forward and backward, and is provided with an alignment mark (not shown) formed on the mask 11. The positions of the alignment marks 12a to 12d formed at the corresponding positions on the photosensitive substrate 12 are detected.

The mask 11 is held by suction on a mask table (not shown), while the photosensitive substrate 12 is held by suction on a substrate table 16. The mask table and the substrate table 16 are attached to a scanning stage (not shown) which is formed in a U-shaped cross section and is moved in the X direction so as to face each other.

The substrate table 16 is attached to the scanning stage via three linear actuators 17 (only two are shown in FIG. 1) displaced in the Z direction. On the surface of the photosensitive substrate 12, these linear actuators 17 are selectively or wholly actuated, shifted in the Z direction, rotated about the X axis (0 X), and rotated. It is leveled by a rotation (0 y) about the Y axis.

The scanning stage (substrate stage) is driven under the control of a control device (exposure control device) (not shown) so that it can reciprocate in the X direction as a scanning direction. The position of the photosensitive substrate 12 is measured by a plurality of position sensors 19 such as a laser interferometer provided on the substrate table 16, and the position of the mask 11 is similarly determined by a laser interferometer provided on a mask table. Are measured by a plurality of position sensors (not shown).

When the scanning stage is stationary, what is projected on the photosensitive substrate 12 is a slit-shaped pattern image, which is an image of a part of the mask pattern formed on the mask 11. The scanning stage, which integrally holds the mask table holding the photosensitive substrate 12 and the substrate table 16 holding the photosensitive substrate 12, is moved and scanned with respect to the illumination area on the mask 11 and the projection optical system 13. All the mask patterns formed on the mask 11 are transferred onto the photosensitive substrate 12.

In this embodiment, the projection optical system 13 is an optical system of an erect real image system at the same magnification. Illumination light is shaped by a blind opening arranged in the illumination optical system 14, and the mask 11 is a trapezoidal field of view 18 a to l 8 e on the photosensitive substrate 12. (See Fig. 2) are illuminated by a plurality of rectangular (slit-shaped) illumination areas (not shown) each including

FIG. 3 shows a lens configuration of the projection optical system 13. All the projection optical systems 13 have the configuration shown in FIG. The projection optical system 13 has a configuration in which two sets of Dyson optical systems are combined, and includes a first partial optical system 13 a (21 to 24) and a second partial optical system 13 b (26 ~ 29).

The first partial optical system 13a has a right-angle prism 21 having a reflecting surface arranged at an inclination of 45 ° facing the mask 11 and an optical axis along the in-plane direction of the mask 11 A plano-convex lens component 22 having a convex surface facing the opposite side of the right-angle prism 21; and a lens component 23 having a meniscus shape as a whole and having a reflecting surface with the concave surface facing the plano-convex lens component 22 side. And a right-angle prism 24 having a reflection surface orthogonal to the reflection surface of the right-angle prism 21 and arranged at an inclination of 45 ° with respect to the surface of the mask 11.

The light path from the illumination optical system 14 through the mask 11 is 90 by the right-angle prism 21. The light is deflected and enters the plano-convex lens component 22 joined to the right-angle prism 21. This lens component 22 is joined with a lens component 23 made of a glass material different from the plano-convex lens component 22. Light from the right-angle prism 21 is joined to the lens components 22 and 23. The light is refracted at the surface 22a and reaches the reflective surface 23a on which the reflective film is deposited. The light reflected by the reflecting surface 23 a is refracted by the joint surface 22 a and reaches the right-angle prism 24 joined to the lens component 22. The light from the lens component 22 is deflected by 90 ° in the optical path by the right-angle prism 24 to form a primary image of the mask 11 on the exit surface side of the right-angle prism 24.

The light from the primary image passes through the second partial optical system 13 b (26 to 29) and passes through the mask 1

A secondary image of 1 is formed on the surface of the photosensitive substrate 12. Since the configuration of the second partial optical system 13b is the same as that of the first partial optical system 13a, detailed description will be omitted. The projection optical system 13 (the first and second partial optical systems 13a and 13b) is a double-sided telecentric optical system. The field stop is located at the position of the primary image formed by the first partial optical system 13a.

(Not shown) are arranged.

The field stop has a trapezoidal opening, and the field stop defines an exposure area on the photosensitive substrate 12 in a trapezoidal shape. That is, as shown in Figure 2, the projected light The science system 13 has a visual field region 18a to 18e defined by a field stop in the projection optical system. The images of these visual field regions 18a to 18e are formed as an equal-size erect image (image having a positive horizontal magnification in the vertical and horizontal directions) on the exposure region on the photosensitive substrate 12. Here, a part of the projection optical system 13 is provided such that the field regions 18a to 18c are arranged along the Y direction in the figure. Further, another part of the projection optical system 13 has the viewing areas 18 d and 18 e arranged along the Y direction at positions different from the viewing areas 18 a to 18 c in the X direction in the figure. It is provided to be.

In each of the viewing areas 18a to 18e, the upper side of the viewing area 18a to 18c (short side of a pair of parallel sides) faces the upper side of the viewing areas 18c and 18e. It is arranged so that. At this time, the trapezoidal viewing area 18a is set so that the sum of the widths of the viewing areas 18a to 18e in the X direction, that is, the moving direction of the scanning stage, is always constant at any position in the Y direction. ~ 18 e are arranged. This is because, when exposing a large exposure area of the photosensitive substrate 12 while moving the scanning stage in the X direction, a uniform exposure amount distribution is obtained over the entire exposure area on the photosensitive substrate 12.

Since the exposure areas 18a to 18c and the exposure areas 18d and 18e on the photosensitive substrate 12 are set apart in the X direction, the pattern extending in the Y direction After being exposed by the discrete discrete exposure areas 18a to 18c, the exposure areas 18d and 18e, which fill the space between them at certain intervals, are exposed in time and space. And the exposure is performed.

On the optical path (optical axis) between the first partial optical system 13 a and the second partial optical system 13 b of the projection optical system 13, the imaging position of the projection optical system 13 is adjusted. Of the projection optical systems 13 are arranged corresponding to those of the projection optical systems 13. The detailed configuration of the imaging position adjusting device 31 is shown in FIG. 4 and FIG.

The imaging position adjusting device 31 includes a first optical member 32, a second optical member 33, and a moving device for sliding the first optical member 32. The moving device includes a plurality of guide rollers 34 for guiding the first optical member 32 in a freely slidable manner, a linear actuator 35 for displacing the first optical member 32 to slide, and a first optical member 32. And a position detection sensor 37 for detecting the position of the first optical member 32. In this embodiment, the first optical member 32 is guided by a plurality of guide rollers 34 so as to be movable in the X direction (or Y direction), and the second optical member 33 is not shown. It is fixed to a frame. However, the first optical member 32 is fixed and the second optical member 33 is configured to move, or both the first and second optical members 32, 33 are configured to be movable. Is also good.

Each of the first optical member 32 and the second optical member 33 is a wedge-shaped glass plate that transmits light having a predetermined wavelength (light in a predetermined band including the wavelength of illumination light). That is, the first optical member 32 has a first entrance surface 32a as a light entrance surface and a first exit surface 32b as a light exit surface oblique to the first entrance surface 32a. are doing. In addition, the second optical member 33 has a second incident surface 33 a as a light incident surface facing the first exit surface 32 b of the first optical member 32 and a second optical member 32. It has a second exit surface 33b as a light exit surface substantially parallel to the one entrance surface 32a.

A plurality of positive pressure grooves 32 c and a plurality of negative pressure grooves 32 d are formed on the first light exit surface 32 b of the first optical member 32. In this embodiment, negative pressure grooves 32 d are arranged on both sides of the positive pressure groove 32 c, respectively, at two locations near both ends. The positive pressure groove 3 2c and the negative pressure groove 3 2d connect the first exit surface 32 of the first optical member 32 and the second entrance surface 33a of the second optical member 33 to each other by a predetermined distance. This groove is used to construct an air bearing as a non-contact device that faces each other in a non-contact manner while maintaining an interval. That is, each of the positive pressure grooves 32c is communicated with a positive pressure supply source (compressed air supply device) P (not shown) through the respective through holes. Is supplied to the positive pressure groove 32c, and urges the first optical member 32 in a direction to separate (float) from the second optical member 33. On the other hand, the negative pressure groove 3 2 d is connected to a negative pressure supply source (vacuum suction device) V (not shown) through the respective through holes, and the negative pressure supply source V is actuated. The air in 2d is sucked in vacuum and urges the first optical member 32 in a direction to make the first optical member 32 approach (contact) the second optical member 33.

By appropriately adjusting and controlling the positive pressure supply source P and the negative pressure supply source V to maintain the repulsive force by the positive pressure groove 32c and the suction force by the negative pressure groove 32d at predetermined values, The first exit surface 32b of the member 32 and the second entrance surface 33a of the second optical member 33 face each other while maintaining a constant gap G. In this embodiment, this gap G is about It was set to 10 m. Note that if the gap G is too large, an optical difference occurs, and therefore, as in the present embodiment, a value of 10 111 to several 10 m is desirable. In any case, the gear G should be set within the optical aberration that can be tolerated by the equipment used (for example, a projection exposure apparatus).

In the linear actuator 35 of the moving device, the tip of the operating shaft is in contact with one side surface of the first optical member 32, and the first optical member 32 is guided by expanding and contracting the operating shaft. Slide (move) along la 3 4. The coil panel 36 urges the other side of the first optical member 32 such that one side of the first optical member 32 comes into contact with the tip of the operating shaft of the linear actuator 35. The position (movement amount) of the first optical member 32 is detected by a position detection sensor 37 such as a potentiometer or a linear encoder, and based on the detected value, the linear actuator 35 is feedback-controlled to obtain a first position. The optical member 32 can be accurately positioned at an arbitrary position with respect to the second optical member 33.

Thereby, the relative dimension (thickness) between the first entrance surface 3 2a of the first optical member 32 and the second exit surface 33b of the second optical member 33 can be arbitrarily finely adjusted. For example, in FIG. 4, the image forming position of the projection optical system 13 can be changed by (5) by sliding the first optical member 32 from the position indicated by the two-dot line to the position indicated by the solid line. As described above, the imaging position adjustment device 31 can precisely adjust the imaging position of each projection optical system 13 in the optical axis direction (Z direction).

On the second entrance surface 33a of the second optical member 33, a contact prevention film 38 such as a chrome film is formed in a rectangular shape, and in a non-operation state, that is, when the air bearing is not operated. In this case, direct contact between the first exit surface 32b of the first optical member 32 and the second entrance surface 33a of the second optical member 33 is prevented.

Referring again to FIG. 2 and FIG. A portion between the mask 11 and the photosensitive substrate 12, and a projection optical system 13 corresponding to the visual field regions 18 a to l 8 c and a projection optical system corresponding to the visual field regions 18 d and 18 e A plurality of (three in this embodiment) focus sensors 20 are arranged in the Y direction between the positions 13 and 13 as indicated by the crosshairs in FIG. 2. These focus sensors 20 emit detection beams toward the surface (pattern surface) of the mask 11 and the surface (exposure surface) of the photosensitive substrate 12, respectively. This is a device for detecting the positions of the surface of the mask 11 and the surface of the photosensitive substrate 12 in the Z direction by detecting the reflected light of the light.

By moving the scanning stage in the X direction and collecting data at an appropriate sampling pitch in the X direction based on the focus signal from each of these focus sensors 20, the X coordinate specified by the scanning stage feed amount And the surface of the mask 11 and the photosensitive substrate 12 at the position corresponding to the Y coordinate defined by the installation position of the focus sensor 20 in the Y direction. .

These surface data are caused by the flatness of the mask 11 and the photosensitive substrate 12, the bending of the mask table and the substrate table 16 due to the holding thereof, and the unevenness of the scanning stage feed. Although this is an example showing the irregularities on the surfaces of the mask 11 and the photosensitive substrate 12, in this embodiment, the mask 11 1 and the photosensitive substrate 12 are based on the respective positions in the Z direction. The relative distance in the Z direction between the substrate and the photosensitive substrate 12 is determined, and this is defined as the surface distance. Then, it is assumed that the mask 11 is an ideal flat surface, and all the irregularities including the irregularities on the surface of the mask 11 are treated as being on the photosensitive substrate 12. This surface data is stored in a storage device (not shown).

Next, the operation of this scanning type exposure apparatus will be described with reference to the figure showing the outline of the processing shown in FIG. First, the scanning stage is moved to a predetermined substrate transfer position at the end in the + X direction, and the photosensitive substrate (plate) 12 is loaded (loaded) onto the substrate table 16 of the scanning stage (ST 1). It is assumed that the mask 11 has already been loaded and held on the mask table of the scanning stage.

After that, the scanning stage is started to move in the X direction in order to perform a preliminary scan, and the mask 11 and the photosensitive substrate 12 are synchronously moved with respect to the projection optical system 13. At this time, it is assumed that the illumination light from the illumination optical system 14 is blocked by an unillustrated shirt.

During this preliminary scan, the relative postures (X, Y positions) of the mask 11 and the photosensitive substrate 12 in the XY plane are detected (ST 2). Specifically, the alignment microscope 15 is extended to a predetermined detection position, and the alignment of the photosensitive substrate 12 is adjusted. When the marks 12a and 12b come to the positions of the viewing areas 18a and 18c, the alignment microscope 15 uses the alignment marks 12a and 12b of the photosensitive substrate 12 and the corresponding masks 11 on the photosensitive substrate 12. The relative position of the alignment marks formed on the photosensitive substrate 12 is detected, and then, when the alignment marks 12 c and 12 d of the photosensitive substrate 12 come to the positions of the viewing areas 18 a and 18 c, the alignment microscope 15 Thus, the relative displacement between the alignment marks 12c and 12d and the corresponding alignment marks formed on the mask 11 are detected.

In addition, during this preliminary scan, the relative distance (Z position) in the Z direction between the mask 11 and the photosensitive substrate 12 is also detected (ST 3) in parallel with the above processing (ST 2). Specifically, the Z-direction positions of the mask 11 and the photosensitive substrate 12 are sampled at a predetermined pitch based on the focus signals of the mask 11 and the photosensitive substrate 12 by the respective focus sensors 20, thereby forming a grid. The relative distance in the Z direction between the mask 11 and the photosensitive substrate 12 corresponding to the predetermined X and Y coordinates defined in the form is stored in the storage device as the surface data. The sampling position of this surface data in the X direction is indicated by a cross line and a cross-dot line in FIG. Note that the higher the number of samplings in the X direction on the photosensitive substrate 12, the better the accuracy. However, the number is appropriately set in consideration of the time required for signal processing and calculation processing.

When the scanning stage has moved to the predetermined end turn-back position in the X direction, the relative positions of the alignment marks on the mask 11 and the corresponding alignment marks 12a to 12d on the photosensitive substrate 12 are determined. In order to minimize the displacement, one or both of the mask 11 and the photosensitive substrate 12 are shifted in the XY plane by a position correction mechanism (not shown) provided on the substrate table 12 and the mask table, The postures of the mask 11 and the photosensitive substrate 12 are aligned with each other by rotating (ST4).

Also, based on surface data as a set of relative distances in the Z direction at discrete positions in the XY plane stored in the storage device, an approximated surface is calculated using an approximation method such as a least square method. (ST 5).

After that, the leveling control amount is calculated (ST6). That is, based on the focal length information (predetermined) of each projection optical system 13, A theoretical imaging position in a state where the first optical member 32 is at a predetermined initial position is calculated, and a focus error (projection optical system) is calculated based on the theoretical imaging position and the approximated surface calculated in ST5. The amount of rotation of the substrate table 16 around the X-axis (θ χ) and the ような direction such that the distance in the Z direction between the image forming position and the approximated curved surface in 13) is minimized in the Y direction. Is calculated, and this is used as a leveling control amount for the linear actuator 17 for adjusting the attitude of the base table 16. When the correction control is also performed for the rotation of the substrate table 16 around the Υ axis, the rotation amount (0 y) is calculated in the same manner, and the leveling control amount for the linear actuator 17 is also calculated. And The leveling control amount is calculated for each predetermined feed amount according to the feed amount (movement amount) of the scanning stage in the X direction.

Next, a new approximated surface obtained by correcting the approximated surface calculated in ST 5 by the leveling control amount calculated in ST 6 is calculated, and further remaining based on the new approximated surface and the theoretical imaging position. The focus errors are calculated, and these are used as the imaging position control amounts for the imaging position adjustment device 31 (ST7).

After the calculation of these control amounts, the blocking of the illumination light by the shirt of the illumination optical system 14 is released, and the main scan is started by moving the scanning stage. Along with the movement of the scanning stage, the linear actuator 17 is operated as appropriate based on the leveling control amount corresponding to the position of the scanning stage in the X direction, and the leveling is performed based on the imaging position control amount. By operating the linear mechanism 35 of the position adjusting device 31 and sliding the first optical member 32 with respect to the second optical member 33 to adjust the overall plate thickness, each projection optical system can be adjusted. The photosensitive substrate 12 is exposed while the imaging position of 13 is almost coincident with the surface of the photosensitive substrate 12 (ST8). Thus, the photosensitive material on the photosensitive substrate 12 is selectively exposed to light, and the pattern images of the mask 11 are sequentially projected and transferred. When the transfer formation of the pattern on the photosensitive substrate 12 is completed, the same operation is repeated by replacing the photosensitive substrate 12 with another photosensitive substrate.

According to the scanning projection exposure apparatus of the present embodiment, as shown in FIG. 7A, during scanning (main scanning), the linear work 17 of the substrate table 16 is controlled based on the leveling control amount. And sensitized substrate 1 2 The focus error at each position on the surface is reduced on average. Further, in addition to this, as shown in FIG. 7B, the focus error which still remains due to this leveling is adjusted by the image forming position adjusting device 31 provided for each projection optical system 13. By controlling based on the imaging position control amount, the imaging position of the projection optical system itself is changed and adjusted to individually reduce the size. In FIG. 7A, what is indicated by a two-dot line is the entire image plane of each projection optical system 13 before adjusting the imaging position, and is indicated by a two-dot line in FIG. 7B. Are individual imaging planes of each of the projection optical systems 13 after adjusting the imaging position.

This eliminates force errors due to irregularities on the surface of the mask 11 and the photosensitive substrate 12, so that exposure processing can be performed over the entire area of the photosensitive substrate 12 in a state close to optimal focus. Thus, microdevices such as liquid crystal display devices with high accuracy and high reliability can be manufactured.

In the above-described embodiment, the above-described leveling and the adjustment of the imaging position are performed based on the surface distance of the relative distance in the Z direction between the mask 11 and the photosensitive substrate 12. It can be carried out only on the basis of the surface data on 11 or only on the basis of the surface data on the photosensitive substrate 12. In addition, the leveling for the average removal of the focus error is performed by operating the actuator 17 for the photosensitive substrate 12, but the operation for the mask 11 is performed. , Or both.

Further, in the image forming position adjusting device 31 according to the present embodiment, the first optical member 32 and the second optical member 33 are arranged so as to face each other at a constant interval in a non-contact state by air bearing. In addition, the imaging position of each projection optical system 13 can be finely adjusted with high accuracy, and since it is non-contact, there is little deterioration over time, and stable adjustment can be performed over a long period of time.

As the non-contact device for the first optical member 32 and the second optical member 33 of the imaging position adjusting device 31, in the above embodiment, the combination of the suction force by the negative pressure and the repulsion force by the positive pressure is used. The present invention is not limited to this. However, the present invention is not limited to this, and a combination of a magnetic attraction force and a positive pressure repulsion force, a negative pressure attraction force And a combination of repulsive force by magnetic force. It may be a combination of a magnetic attraction and a magnetic repulsion as well as a gravity, a biasing force by a panel, and the above-mentioned positive pressure or negative pressure, magnetic force, or the like. Is also good.

Further, if a drive mechanism for tilting the entire imaging position adjusting device 31 is provided, the projection position of each projection optical system 13 can be shifted. For example, if the projection magnification of each projection optical system 13 is adjusted by expansion and contraction of the photosensitive substrate 12 and the like, the amount of overlap between the trapezoidal field regions 18a and 18d changes. Therefore, the amount of overlap between the trapezoidal viewing regions 18a and 18d can be adjusted by tilting the entire imaging position adjusting device 31 by a drive mechanism (not shown). As described above, according to the present embodiment, the imaging position of each projection optical system 13 in the optical axis direction and the Y direction orthogonal to the optical axis direction can be adjusted by the imaging position adjustment device 31. The structure of the system 13 can be simplified.

The embodiments described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element described in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, in the above-described embodiment, a description will be given of a case where the mask 11 and the photosensitive substrate 1 are integrally moved by a scanning stage, and the present invention is applied to a scanning projection exposure apparatus configured to perform exposure by equal-magnification projection. However, it can also be applied to a scanning projection exposure apparatus that exposes the mask and the photosensitive substrate while independently and synchronously moving in the same direction or in the opposite direction.The projection method is also limited to 1: 1 projection. Instead, the image may be projected in a reduced or enlarged manner. Further, the image forming position adjusting apparatus of the present invention can be applied not only to a scanning type exposure apparatus but also to a stationary type exposure apparatus (for example, a stepper).

Further, in the exposure apparatus of the present embodiment, g-rays (wavelength: 436 nm), i-rays (wavelength: 365 nm), and KrF excimer laser generated from a mercury lamp are used as exposure illumination light.

(Wavelength 2 4 8 nm), A r F excimer laser (wavelength 1 9 3 nm), F ₂ laser

(Wavelength 1 5 7 nm), A r 2 laser (wavelength 1 2 6 nm), and metal vapor lasers also For example, a harmonic such as a YAG laser can be used. In addition, a single-wavelength laser in the infrared or visible range oscillated from a DFB semiconductor laser or a fiber laser is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and yttrium), and a non-linear optical amplifier is used. A harmonic converted to ultraviolet light using a crystal may be used.

The semiconductor device manufactured by the exposure apparatus of the present embodiment includes, for example, a display device including a liquid crystal display device and a plasma display, a semiconductor device, a thin-film magnetic head, an imaging device (CCD), and the like. Such a semiconductor device includes a step of designing the function and performance of the device, a step of manufacturing a reticle based on the design step, a step of manufacturing a substrate such as a glass plate or a wafer, and a reticle using the exposure apparatus. It is manufactured through a step of transferring the above pattern to a substrate, a step of assembling a device (including a dicing step, a bonding step, and a package step), and an inspection step.

The exposure apparatus of the present embodiment incorporates a plurality of projection optical systems 13 having an illumination optical system 14 composed of a plurality of lenses and an imaging position adjustment device 31 into an exposure apparatus main body, and performs optical adjustment. In addition to this, it can be manufactured by attaching a scanning stage consisting of a large number of mechanical parts to the exposure apparatus main body, connecting wiring and piping, and performing overall adjustment (electrical adjustment, operation confirmation, etc.). It is desirable that the exposure apparatus be manufactured in a clean room in which the temperature and the degree of cleanliness are controlled.

All disclosures, including the description, claims, drawings, and abstract, of Japanese Patent Application No. 10-27,1270, filed September 25, 1998, are: It is incorporated here by reference as it is.

Claims

The scope of the claims

I. An image forming position adjusting device for adjusting an image forming position of an optical system, comprising: first and second optical members having opposed inclined surfaces and transmitting light of a predetermined wavelength; A non-contact device for non-contact facing,

An imaging position adjusting device comprising: a moving device that relatively moves the first optical member and the second optical member along a direction that intersects the optical axis of the optical system.

2. The imaging position adjusting apparatus according to claim 1, wherein the first and second optical members are wedge-shaped glass plates.

3. The imaging position adjusting device according to claim 1, wherein the non-contact device includes a non-contact bearing.

4. The imaging position adjusting device according to claim 3, wherein the non-contact bearing is a gas bearing.

5. The imaging position adjusting device according to claim 1, further comprising a drive mechanism that integrally drives the first optical member and the second optical member with respect to an optical axis of the optical system.

6. The imaging position adjustment device according to claim 1, wherein the moving device drives the first optical member and the second optical member along a direction substantially orthogonal to the optical axis.

7. An exposure apparatus for exposing a pattern to a substrate by a projection optical system, the exposure apparatus being provided in the projection optical system, having first and second inclined surfaces facing each other, and transmitting light of a predetermined wavelength. An optical member;

An exposure apparatus comprising: a moving device that relatively moves the first optical member and the second optical member along a direction that intersects the optical axis of the projection optical system. ―

8. The exposure apparatus according to claim 7, further comprising a non-contact device for causing the opposed inclined surfaces to face each other in a non-contact manner.

9. The exposure apparatus according to claim 7, wherein each of the first and second optical members is a wedge-shaped glass plate.

10. The exposure apparatus according to claim 8, wherein the non-contact device includes a non-contact type bearing.

II. The non-contact type bearing is a gas bearing. Exposure equipment.

12. The exposure apparatus according to claim 7, further comprising a driving mechanism that integrally drives the first optical member and the second optical member with respect to an optical axis of the projection optical system.

13. The exposure apparatus according to claim 7, wherein the moving device drives the first optical member and the second optical member along a direction substantially orthogonal to the optical axis.

14. The exposure apparatus according to claim 7, further comprising a mask stage for holding a mask having the pattern.

15. The exposure apparatus according to claim 14, further comprising a detection device that detects information about a relative distance between the substrate and the mask in the optical axis direction.

16. The exposure apparatus according to claim 15, wherein the moving device relatively moves the first optical member and the second optical member based on a detection result of the detection device.

17. The exposure apparatus according to claim 7, wherein the exposure apparatus is a scanning exposure apparatus that exposes the pattern while moving the substrate.

18. The exposure apparatus according to claim 7, wherein the exposure apparatus includes a plurality of the projection optical systems.

1 9. The first projection optical system so that a part of the projection area of the first projection optical system and a part of the projection area of the second projection optical system among the plurality of projection optical systems are different from each other. 19. The exposure apparatus according to claim 18, wherein the second projection optical system and the second projection optical system are provided.

20. An imaging position adjusting method for adjusting an imaging position of an optical system, wherein first and second optical members having opposed inclined surfaces and transmitting light of a predetermined wavelength are arranged in the optical system. Steps to set up,

Moving the first optical member and the second optical member along the inclined surface in a non-contact manner.

21. The imaging position adjustment method according to claim 20, further comprising a step of integrally driving the first optical member and the second optical member with respect to an optical axis of the optical system.

22. The connection according to claim 20, wherein an incident surface of the first optical member on which the light of the predetermined wavelength is incident and an emission surface of the second optical member on which the light of the predetermined wavelength exits are substantially parallel. Image position adjustment method.

23. An exposure method for exposing a pattern to a substrate by a projection optical system, A step having, in the projection optical system, first and second optical members having opposed inclined surfaces and transmitting exposure light of a predetermined wavelength;

Relative moving the first optical member and the second optical member along a direction intersecting the optical axis of the projection optical system.

24. The exposure method according to claim 23, wherein the first optical member and the second optical member perform the relative movement in a non-contact manner.

25. The exposure method according to claim 23, wherein an incident surface of the first optical member on which the exposure light is incident is substantially parallel to an emission surface of the second optical member from which the exposure light exits.

26. The exposure method according to claim 23, further comprising a step of driving the first optical member and the second optical member integrally with respect to the optical axis of the projection optical system.

27. The exposure method according to claim 23, further comprising: exposing the pattern while moving the substrate.

28. The exposure method according to claim 23, further comprising a step of exposing the substrate while partially overlapping the pattern.

29. A substrate on which the pattern is exposed using the exposure method according to claim 23.