JP2007081314A - Control method for stage device, exposure system and manufacturing method for device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method, etc. for a stage device in which a fixed mirror set in a projection optical system for performing position control for the stage device is set at a position independent of magnification of the projection optical system. <P>SOLUTION: A first stage RST movable while holding a first substrate R, a second stage WST movable while a second substrate W, and an optical element part PL arranged between the first stage RST and the second stage WST are provided. Based on position measurement information of a first direction of the first stage RST, the second stage WST and the optical element part PL and optical property of the optical element part PL, the first substrate R and the second substrate W are positioned in the control method for the stage devices RST and WST. Position-measured parts 61 and 63 in the optical element part PL are separated in a second direction, and arranged at several points having a positional relationship independent of the optical property of the optical element part PL. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for controlling a stage apparatus for positioning a substrate.

  A sensitive substrate is irradiated with illumination light (energy rays such as ultraviolet rays, X-rays, and electron beams) on a mask or the like on which a circuit pattern is drawn, and through a projection optical system having the same magnification, a predetermined reduction magnification or enlargement magnification. There is known an exposure apparatus that forms a circuit pattern of a semiconductor device, a liquid crystal display device, or the like by performing projection exposure on a semiconductor wafer or a glass plate coated with a resist layer. In such an exposure apparatus, there is a stage apparatus (mask stage, substrate stage) on which a mask or a sensitive substrate is placed and precisely moved two-dimensionally in a plane (XY plane) under position servo control by a laser interferometer. Provided.

The laser interferometer emits coherent light toward the fixed mirror installed in the projection optical system and the movable mirror installed in the stage device, and is projected by the interference light generated by the reflected light from the fixed mirror and the movable mirror. The relative distance between the optical system and the stage apparatus is measured. For this reason, the projection optical system includes a fixed mirror (first fixed mirror) for measuring the position of the mask stage and a fixed mirror (second fixed mirror) for measuring the position of the substrate stage, respectively, at predetermined positions. is set up.
The installation positions of the first fixed mirror and the second fixed mirror in the Z direction are defined by the projection magnification of the projection optical system. Then, by disposing the first fixed mirror and the second fixed mirror at a position defined by the projection magnification of the projection optical system, it is possible to measure the positional deviation between the mask on the mask stage and the photosensitive substrate on the substrate stage. Become.
As a result, the positional deviation between the mask and the photosensitive substrate can be minimized, so that the pattern formed on the photosensitive substrate on the mask can be exposed with high accuracy.
JP-A-10-275770 JP-A-11-204406

In the above-described technique, when the inverted imaging type projection optical system is used, the first fixed mirror and the second fixed mirror can be directly fixed to the lens barrel accommodating the projection optical system.
However, when an upright imaging type projection optical system is used, as shown in FIG. 5, the optical pivotal position is located above or below the lens barrel. It becomes impossible to directly fix either one or both of them to the lens barrel. In such a case, it is conceivable to install an extension member between the lens barrel and the fixed mirror. However, since the mechanical (vibration) and thermal instability occurs, there is an error in the position measurement of the stage device. This is likely to occur, and the positioning accuracy of the stage device is deteriorated.

  The present invention has been made in view of the above-described circumstances, and a fixed mirror installed in a projection optical system for performing position control of a stage apparatus can be installed at a position independent of the magnification of the projection optical system. It is an object of the present invention to provide a possible stage apparatus control method, an exposure method using the same, and a device manufacturing method.

In the method for controlling a stage apparatus, the exposure method, and the device manufacturing method according to the present invention, the following means are employed in order to solve the above problems.
In order to solve the above-mentioned problem, the first stage (RST) capable of moving in the first direction while holding the first substrate (R) will be described with reference to the drawings showing an embodiment. A second stage (WST) that can move in the first direction while holding the second substrate (W), and the first stage and the second stage in a second direction that intersects the first direction. An optical element portion (PL) disposed between the first stage, the second stage, and the position measurement information in the first direction of the optical element portion, and the optical characteristics of the optical element portion. Based on the control method of the stage device (RST, WST) for positioning the first substrate and the second substrate, the position measuring unit (61, 63) in the first direction in the optical element unit is , Spaced apart in the second direction and front It was arranged in a plurality of locations having a positional relationship which does not depend on the optical properties of the optical element unit.
According to the present invention, the position measurement unit in the first direction of the optical element unit is disposed in a plurality of locations that are separated in the second direction and have a positional relationship that does not depend on the optical characteristics of the optical element unit. The part can be directly arranged on the optical element part without using an extension member or the like.

Further, the position measurement of the first stage (RST), the second stage (WST), and the optical element unit (PL) is not measured by independent measurement systems (52, 54, 62, 64). In addition, the position measurement unit in the first direction in the optical element unit can be easily separated in the second direction and arranged at a plurality of locations having a positional relationship that does not depend on the optical characteristics of the optical element unit.
The position measurement unit (61, 63) includes a first measurement unit (61) corresponding to the first stage (RST) and a second measurement unit (63) corresponding to the second stage (WST). A distance along the second direction from the optical pivot position (P) of the optical element section (PL) to the first measurement section and the first distance from the optical pivot position to the second measurement section. When the ratio of the distance along the two directions is set to a value different from the projection magnification of the optical element unit, the position measurement unit in the first direction is separated in the second direction and the optical element unit Arranged at a plurality of locations having a positional relationship that does not depend on optical characteristics.
Further, if the optical element section (PL) has an erecting image forming characteristic, the position measuring section can be directly arranged on the optical element section.

For example, the first stage (RST), the optical element unit (PL), and the second stage (WST) are arranged along an optical path (AX) along which light (EL) that passes through the optical element unit travels. The position measurement parts (61, 63) can be arranged in order from the light incident side end to the light emission side end of the optical element part.
In addition, for example, the position measurement unit (61, 63) can be arranged so as to be close to the first stage (RST) or the second stage (WST).

For example, the optical element unit (PL) is a catadioptric imaging system, and the first measurement unit (61) is installed between the reflection unit installation position and the incident side end in the optical element unit. In addition, the second measuring unit (63) can be installed between the installation position of the reflecting unit and the emission side end.
Further, for example, the optical element part (PL) is a catadioptric imaging system, and both the first measuring part (61) and the second measuring part (63) It can install between the incident side edge parts.
Further, for example, the optical element part (PL) is a catadioptric imaging system, and both the first measuring part (61) and the second measuring part (63) It can be installed between the output side end.

The present invention also provides a first stage (RST) that can move in the first direction while holding the first substrate (R), and a first stage that can move in the first direction while holding the second substrate (W). A second stage (WST) and an optical element part (PL) disposed between the first stage and the second stage in a second direction orthogonal to the first direction, and the first stage , A stage device (RST, RST) for positioning the first substrate and the second substrate based on position measurement information in the first direction of the second stage and the optical element unit, and optical characteristics of the optical element unit. In the WST control method, the position measurement unit (65) in the first direction in the optical element unit is arranged at an optical pivotal position (P) of the optical element unit.
According to the present invention, the position measuring unit in the first direction of the optical element unit can be directly arranged on the optical element unit without using an extension member or the like.

In addition, the position measurement of the first stage (RST), the second stage (WST), and the optical element unit (PL) can be easily performed by means of independent measurement systems (52, 54, 66). In addition, the position measuring unit in the first direction in the optical element unit can be arranged at the optical pivotal position.
Further, if the optical element part (PL) has an imaging characteristic of an inverted inverted image, the position measurement part can be directly arranged on the optical element part.

The second invention is a mask stage (RST) that can move in the first direction while holding the mask (R), and a substrate stage (WST) that can move in the first direction while holding the photosensitive substrate (W). A projection optical system (PL) disposed between the mask stage and the substrate stage, wherein the mask stage and the substrate stage are the stages of the first invention. It was controlled by the control method.
According to the present invention, since the mask stage and the wafer stage are well controlled so as to have a predetermined positional relationship, the pattern formed on the mask can be exposed onto the wafer with high accuracy.

According to a third invention, in the device manufacturing method including the lithography process, the exposure apparatus (EX) of the second invention is used in the lithography process.
According to the present invention, a device having a fine pattern can be efficiently manufactured.

  In addition, in order to explain this description in an easy-to-understand manner, the description has been made in association with the drawings showing one embodiment, but it goes without saying that the present invention is not limited to the embodiment.

According to the present invention, the following effects can be obtained.
In the present invention, since the position measurement part in the first direction of the optical element part can be directly arranged on the optical element part without using an extension member or the like, the position measurement in the first direction of the optical element part is a machine. (Vibration) and thermal stability. Thereby, based on the position of the optical element part in the first direction, the first stage and the second stage can be positioned in the first direction with high accuracy.
Therefore, the pattern formed on the mask can be exposed to the wafer with high accuracy, and a device having a fine pattern can be efficiently manufactured.

Embodiments of a stage apparatus control method, an exposure apparatus, and a device manufacturing method according to the present invention will be described below with reference to the drawings.
FIG. 1 is a view showing a schematic configuration of an exposure apparatus EX of the present embodiment.
The exposure apparatus EX transfers the pattern PA formed on the reticle R to each shot area on the wafer W via the projection optical system PL while moving the reticle R and the wafer W synchronously in the one-dimensional direction. A scanning type exposure apparatus, that is, a so-called scanning stepper.
Then, the exposure apparatus EX projects onto the wafer W the illumination optical system IL that illuminates the reticle R with the exposure light EL, the reticle stage RST that is movable while holding the reticle R, and the exposure light EL that is emitted from the reticle R. A projection optical system PL, a wafer stage WST that supports and moves the wafer W, and a controller CONT that controls the exposure apparatus EX in an integrated manner are provided.
In the following description, the direction that coincides with the optical axis AX of the projection optical system PL is the Z-axis direction, and the synchronous movement direction (scanning direction) between the reticle R and the wafer W in the plane perpendicular to the Z-axis direction is the X-axis. The direction perpendicular to the direction, the Z-axis direction, and the Y-axis direction (non-scanning direction) is defined as the Y-axis direction. In addition, the rotation (inclination) directions around the X, Y, and Z axes are the θX, θY, and θZ directions, respectively.

  The illumination optical system IL illuminates the reticle R supported by the reticle stage RST with the exposure light EL. The illumination light source emits the exposure light EL, and the illuminance of the exposure light EL emitted from the exposure light source. A uniform optical integrator, a condenser lens that collects the exposure light EL from the optical integrator, a relay lens system, a variable field stop that sets the illumination area on the reticle R by the exposure light EL in a slit shape, etc. (all not shown) have. The predetermined illumination area on the reticle R is illuminated with the exposure light EL having a uniform illuminance distribution by the illumination optical system IL.

As the exposure light EL emitted from the illumination optical system IL, for example, far ultraviolet light (g-line, h-line, i-line) and KrF excimer laser light (wavelength 248 nm) emitted from a mercury lamp, DUV light), vacuum ultraviolet light (VUV light) such as ArF excimer laser light (wavelength 193 nm) and F ₂ laser light (wavelength 157 nm), or the like is used.

The reticle stage RST is movable while holding the reticle R, and, for example, the reticle R is fixed by vacuum suction (or electrostatic suction). Reticle stage RST can be moved two-dimensionally in a plane perpendicular to optical axis AX of projection optical system PL, that is, in the XY plane, and can be slightly rotated in the θZ direction.
The reticle stage RST is driven by a reticle stage driving unit RSTD such as a linear motor. Reticle stage driving unit RSTD is controlled by control unit CONT.

A movable mirror 51 is provided on the reticle stage RST. A laser interferometer 52 is provided at a position facing the movable mirror 51. Thus, the position of the reticle R on the reticle stage RST in the two-dimensional direction (XY direction) and the rotation angle in the θZ direction (including rotation angles in the θX and θY directions in some cases) are measured by the laser interferometer 52 in real time. Is done.
And the measurement result of the laser interferometer 52 is output to the control apparatus CONT. The control device CONT controls the position of the reticle R supported by the reticle stage RST by driving the reticle stage drive unit RSTD based on the measurement result of the laser interferometer 52.

The projection optical system PL projects and exposes the pattern of the reticle R onto the wafer W at a predetermined projection magnification β. The projection optical system PL is composed of a plurality of optical elements including optical elements provided at the front end portion on the wafer W side, and these optical elements are supported by a lens barrel PK.
The projection optical system PL is a reduction system having a projection magnification β of, for example, 1/4, 1/5, or 1/8. Note that the projection optical system PL may be either an equal magnification system or an enlargement system.
The projection optical system PL may be any of a refractive type, a reflective type, and a catadioptric type. In the present embodiment, the refraction type will be described.
The projection optical system PL may be either an inverted imaging type that forms an inverted inverted image or an erect imaging type that forms an erect image.

  Fixed mirrors 61 and 63 are respectively fixed near the upper end and lower end of the lens barrel PK, and laser interferometers 62 and 64 are provided at positions facing the fixed mirrors 61 and 63, respectively. As a result, the position in the two-dimensional direction (XY direction) of the projection optical system PL accommodated in the lens barrel PK is measured in real time by the laser interferometers 62 and 64.

Wafer stage WST supports wafer W, and supports Z stage 41 and Z stage 41 that hold wafer W and are micro-driven in three degrees of freedom in the Z-axis direction, θX direction, and θY direction. However, an XY stage 42 that can move in at least three directions of freedom in the X-axis direction, the Y-axis direction, and the θZ direction, a wafer surface plate 43 that supports the XY stage 42 so as to be movable in the XY plane, and the like are provided.
Wafer stage WST is driven by a wafer stage drive unit WSTD such as a linear motor. Wafer stage drive unit WSTD is controlled by control unit CONT.
Then, by driving the Z stage 41, the position (focus position) of the wafer W held on the Z stage 41 in the Z-axis direction is controlled. Further, by driving the XY stage 42, the position of the wafer W in the XY direction (position in a direction substantially parallel to the image plane of the projection optical system PL) is controlled.

A movable mirror 53 is provided on wafer stage WST (Z stage 41). A laser interferometer 54 is provided at a position facing the moving mirror 53. Accordingly, the position and rotation angle of wafer W on wafer stage WST in the two-dimensional direction are measured in real time by laser interferometer 54, and the measurement result is output to control device CONT.
Then, the control device CONT drives the wafer stage WST via the wafer stage drive unit WSTD based on the measurement result of the laser interferometer 54, so that the X axis and Y axis of the wafer W supported on the wafer stage WST. Positioning in the direction and θZ direction.

Next, details of the stage control method will be described.
FIG. 2 is a diagram for explaining a stage control method. In the following description, control in the X direction of reticle stage RST and wafer stage WST will be described. However, since the same control is performed in the Y direction, description thereof will be omitted.

As shown in FIG. 2, the position measurement result of the movable mirror 51 by the laser interferometer 52 (the position of the reticle stage RST) is A _RS , and the position measurement result of the fixed mirror 61 by the laser interferometer 62 (the upper end portion of the projection optical system PL). A near position) is A _U , the position measurement result of the fixed mirror 63 by the laser interferometer 64 (position near the lower end of the projection optical system PL) is A _D , and the position measurement result of the movable mirror 53 by the laser interferometer 54 (wafer) position of the stage WST) is referred to as _{a WS.}
Further, the position of the optical pivotal position P of the projection optical system PL is A _PIV , the distance in the Z direction from the optical pivotal position P of the projection optical system PL to the fixed mirror 61 is H _U , and the optical pivotal of the projection optical system PL the Z-direction distance from the position P to the fixed mirror 63 and H _D.
Further, the actual position at which the pattern PA of the reticle R is imaged on the wafer stage WST (wafer W) is A _IMG , and the difference between the position at which the pattern PA is actually imaged and the position A _AIM to be imaged (image shift amount) ) Is I.
Thereby, the image shift amount I is defined as shown in the equation (1).

Further, the position A _IMG at which the image of the pattern PA is actually exposed is obtained from the position A _PIV of the optical pivotal position P of the projection optical system PL and the position A _{RS of the} reticle stage RST as shown in Expression (2). It is done.
Note that the projection magnification of the projection optical system PL is mag, a negative number in the case of an inverted imaging type (an inverted inverted image), and a positive number in the case of an erecting imaging type (an erect image). To express.

Further, the position A _PIV of the optical pivot position P of the projection optical system PL is determined by the distance H _{U in} the Z direction from the optical pivot position P to the fixed mirror 61 and the optical pivot position P as shown in Expression (3). and the distance H _D in the Z direction to the fixed mirror 63 from the position a _D of the vicinity of the position a _U and the lower end portion of the vicinity of the upper end portion of the projection optical system _PL, and is Karakara determined.

  Therefore, when the position and orientation of the projection optical system PL change, if the positions of the reticle stage RST and wafer stage WST are unchanged, the generated image deviation I is expressed by the following equation (1) to (3). As shown in 4).

When the image shift I occurs, it becomes difficult to form a fine pattern on the wafer W. For this reason, it is necessary to minimize the image shift I by finely moving the reticle stage RST and the wafer stage WST (position correction).
Here, if the correction amount of the reticle stage RST is C _R and the correction amount of the wafer stage WST is C _W , the image shift I _C after the position correction of the reticle stage RST and wafer stage WST is expressed by equation (5). It is represented by

When the reticle stage RST and wafer stage WST are controlled, the correction amounts C _R and C _W are set so that the image shift I _C after the position correction of the reticle stage RST and wafer stage WST is minimized. It is necessary to ask.

Incidentally, in the conventional method of controlling the reticle stage RST and wafer stage WST, the installation position _{H D} of the installation position _{H U} and fixed mirror 63 of the fixed lens 61, as shown in equation (6), of the projection optical system PL It is defined by the projection magnification mag.

  When Expression (6) is applied to Expression (4), the image shift I in the conventional stage control method is expressed by Expression (7).

Further, the image shift I _C after stage correction in the conventional stage control method is expressed by Expression (8).

In the conventional stage control method, the positions of reticle stage RST (moving mirror 51) and wafer stage WST (moving mirror 53) are relative to fixed mirrors 61 and 63 fixed near the upper end and the lower end of barrel PK. It is measured by the relative position (see FIG. 5).
Therefore, the position correction amounts C _R and C _W of the reticle stage RST and wafer stage WST are expressed by equations (9-1) and (9-2). Α is an arbitrary coefficient.

Expressions (10-1) and (10-2) can be obtained as one solution of the position correction amounts C _R and C _W of reticle stage RST and wafer stage WST.

  That is, the reticle stage RST and the wafer stage WST are finely moved in the opposite directions by the same amount with respect to the measurement results of the laser interferometers 52 and 54, thereby eliminating the image shift I.

When the above-described method is used, when the projection magnification mag is a negative number, that is, when the projection optical system PL is an inverted imaging type, the image shift I can be solved satisfactorily.
However, when the projection magnification mag is a positive number, that is, when the projection optical system PL is an erecting imaging type, as shown in FIG. 5, either one of the fixed mirror 61 and the fixed mirror 63 is placed above the reticle. Or it will be necessary to arrange | position below a wafer. Installation position H _U and the installation position H _D of the fixed lens 63 of the fixed lens 61, since it is defined by the projection magnification mag of the projection optical system PL, and that the fixed mirror 61 and fixed mirror 63 disposed in an arbitrary position It is not possible.

On the other hand, in the stage control method in the exposure apparatus EX of the present embodiment, the fixed mirror 61 and the fixed mirror 63 can be arranged at arbitrary positions that do not depend on the projection magnification mag of the projection optical system.
In the exposure apparatus EX of the present embodiment, the position of the reticle stage RST and wafer stage WST (moving mirrors 51 and 53) and the projection optical system PL (fixed mirrors 61 and 63 fixed to the vicinity of the upper end and the lower end of the barrel PK). Is measured by using laser interferometers 52, 54, 62, and 64 with a built-in reference mirror. For this reason, since these positions are measured independently, the fixed mirrors 61 and 63 for measuring the position of the projection optical system PL can be set at arbitrary Z-direction positions. In other words, since the differential laser interferometer that measures the positions of the reticle stage RST and the wafer stage WST based on the relative position of the lens barrel PK with respect to the fixed mirrors 61 and 63 is not used, the fixed mirrors 61 and 63 are projected at the projection magnification mag. It is possible to arrange at any position in the Z direction that does not depend on.

Even when the fixed mirrors 61 and 63 are arranged at arbitrary positions that do not depend on the projection magnification mag, the image shift I can be obtained by Expression (4).
Then, assuming that the correction amount of the reticle stage RST is C _R and the correction amount of the wafer stage WST is C _W , the image shift I _C after the position correction of the reticle stage RST and the wafer stage WST is expressed by Expression (11). expressed.

As described above, in the measurement system (laser interferometers 52, 54, 62, and 64) of this embodiment, the positions of reticle stage RST and wafer stage WST and the position of projection optical system PL are measured independently. Accordingly, the correction amount _{C W} of the correction amount _{C R} and the wafer stage WST of the reticle stage RST, using any coefficient alpha, the formula (12-1), is expressed as shown in Equation (12-2).

  Thus, it can be seen that the degree of freedom is increased as compared with the equations (9-1) and (9-2).

Equations (13-1) and (13-2) are obtained as one solution of the position correction amounts C _R and C _W of the reticle stage RST and wafer stage WST.

  In the above equations (13-1) and (13-2), the position error of each stage RST and WST is corrected by each stage RST and WST itself, and is fixed near the upper end of the projection optical system PL (lens barrel PK). The measured value of mirror 61 is used only for correcting the position of reticle stage RST, and the measured value of fixed mirror 63 near the lower end of projection optical system PL (lens barrel PK) is used only for correcting the position of wafer stage WST. Is the case.

In addition, when the position error of each stage RST, WST is corrected by each stage RST, WST itself, and all other image shift components are eliminated only by position correction of reticle stage RST, reticle stage RST and wafer stage Equations (14-1) and (14-2) are obtained as solutions of the WST position correction amounts C _R and C _W.

Further, when the position error of each stage RST, WST is corrected by each stage RST, WST itself, and all other image shift components are eliminated only by position correction of wafer stage WST, reticle stage RST and wafer stage are corrected. Equations (15-1) and (15-2) are obtained as solutions of the WST position correction amounts C _R and C _W.

Further, the position error of each stage RST, WST is corrected by each stage RST, WST itself, and the other image shift components are eliminated by performing the same amount and same position correction of reticle stage RST and wafer stage WST. Equations (16-1) and (16-2) are obtained as solutions of the position correction amounts C _R and C _W of the reticle stage RST and wafer stage WST.

As described above, according to the stage control method of the present embodiment, not only when the projection optical system PL is an inverted imaging type (projection magnification mag is a negative number), the projection optical system PL is an upright imaging type. Even in the case of (the projection magnification mag is a positive number), the image shift I can be solved satisfactorily.
That is, the installation position H _U and the installation position H _D of the fixed lens 63 of the fixed lens 61, because they are not defined by the projection magnification mag of the projection optical system PL, and the fixed mirror 61 and 63 anywhere barrel PK Can be arranged. In other words, the fixed mirrors 61 and 63 can be directly disposed on the lens barrel PK without using an extension member that tends to be unstable in terms of vibration and heat between the fixed mirrors 61 and 63 and the lens barrel PK. Therefore, the image shift I can be solved satisfactorily.

Next, a case where one fixed mirror 65 is used as a fixed mirror to which the lens barrel PK is fixed in order to measure the position of the projection optical system PL will be described.
FIG. 3 is a diagram for explaining another embodiment of the stage control method. In the following description, control in the X direction of reticle stage RST and wafer stage WST will be described. However, since the same control is performed in the Y direction, description thereof will be omitted.

As shown in FIG. 3, the fixed mirror 65 is installed at the same position in the Z direction as the optical pivotal position P of the projection optical system PL. A laser interferometer 66 is provided at a position facing the fixed mirror 65. Thereby, the position in the two-dimensional direction (XY direction) of the projection optical system PL accommodated in the lens barrel PK is measured in real time by the laser interferometer 66.
Instead of using the two fixed mirrors 61 and 63, one fixed mirror 65 is used when the projection magnification of the projection optical system PL is a negative number of mag, that is, the projection optical system PL is an inverted imaging type. It is particularly useful in cases.
_Assuming that the position of the fixed mirror 65 is A _M , the image shift I is obtained by Expression (17).

Then, assuming that the correction amount of the reticle stage RST is C _R and the correction amount of the wafer stage WST is C _W , the image shift I _C after the position correction of the reticle stage RST and the wafer stage WST is expressed by Expression (18). expressed.

Accordingly, the position correction amounts C _R and C _W of the reticle stage RST and wafer stage WST are expressed by equations (19-1) and (19-2). Α is an arbitrary coefficient.

Expressions (20-1) and (20-2) are obtained as one solution of the position correction amounts C _R and C _W of the reticle stage RST and wafer stage WST.

  In the above equations (20-1) and (20-2), the position error of each stage RST and WST is corrected by each stage RST and WST itself, and the fixed mirror 65 of the projection optical system PL (lens barrel PK) is corrected. This is a case where the measurement value is used for position correction of reticle stage RST and wafer stage WST.

In addition, when the position error of each stage RST, WST is corrected by each stage RST, WST itself, and all other image shift components are eliminated only by position correction of reticle stage RST, reticle stage RST and wafer stage position correction amount _C R of WST, as a solution of _{C W,} equation (21-1), the formula (21-2) is obtained.

Further, when the position error of each stage RST, WST is corrected by each stage RST, WST itself, and all other image shift components are eliminated only by position correction of wafer stage WST, reticle stage RST and wafer stage are corrected. Equations (22-1) and (22-2) are obtained as solutions of the WST position correction amounts C _R and C _W.

  As described above, according to the stage control method of this embodiment, it is possible to satisfactorily eliminate the image shift I particularly when the projection optical system PL is an inverted imaging type (projection magnification mag is a negative number). Can do. That is, instead of the plurality of fixed mirrors 61 and 63, the fixed mirror 65 is simply installed on the lens barrel PK, so that the extension member that tends to be unstable in terms of vibration and heat between the fixed mirror 65 and the lens barrel PK. The fixed mirror 65 can be arranged directly on the lens barrel PK without using the. Therefore, the image shift I can be solved satisfactorily.

Although the embodiment of the present invention has been described above, the operation procedure shown in the above-described embodiment, or the shapes and combinations of the constituent members are examples, and the process is within the scope not departing from the gist of the present invention. Various changes can be made based on conditions and design requirements.
For example, the present invention includes the following modifications.

In the embodiment described above, the fixed mirror 61 is installed between the optical pivot position P and the incident side end of the projection optical system PL, and the fixed mirror 63 is disposed between the optical pivot position P and the emission side end. Although the case where it installs was demonstrated, it is not restricted to this.
Since the fixed mirrors 61 and 63 can be installed at arbitrary Z-direction positions, for example, the fixed mirrors 61 and 63 may be arranged close to the reticle stage RST or wafer stage WST.

In the embodiment described above, the case where the projection optical system PL is a refraction type composed of only the reflection optical element has been described. However, as described above, the reflection type includes only the reflection optical element, and includes the reflection optical element and the refraction optical element. It may be a catadioptric type.
In the case of the catadioptric type, for example, the fixed mirror 61 is installed between the installation position of the reflection optical element (corresponding to the optical pivot position P) in the projection optical system PL and the incident side end, and the fixed mirror 63 is It can be installed between the installation position of the reflective optical element and the exit side end. For example, both the fixed mirror 61 and the fixed mirror 63 can be installed between the installation position of the reflective optical element and the incident side end. For example, both the fixed mirror 61 and the fixed mirror 63 can be installed between the installation position of the reflective optical element and the output side end.

The exposure apparatus EX of the above embodiment can be applied to a scanning type exposure apparatus that exposes the pattern of the reticle R by synchronously moving the reticle R and the wafer W, and the reticle R and the wafer W are stationary. In this state, the pattern of the reticle R is exposed, and it can be applied to a step-and-repeat type exposure apparatus that sequentially moves the wafer W stepwise.
The exposure apparatus EX may be an immersion type exposure apparatus that exposes the wafer W by disposing the liquid between the projection optical system PL and the wafer W and solving the liquid.

  The use of the exposure apparatus EX is not limited to an exposure apparatus for manufacturing a semiconductor or an exposure apparatus for liquid crystal that exposes a liquid crystal display element pattern on a square glass plate, but exposure for manufacturing a thin film magnetic head. Widely applicable to devices.

The exposure apparatus EX of the present embodiment is manufactured by assembling various subsystems including the constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Is done. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy.
The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus.
The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  Then, as shown in FIG. 4, the semiconductor device includes a step 201 for designing the function and performance of the device, a step 202 for producing a mask (reticle) based on the design step, a substrate (wafer, Glass plate) step 203, substrate processing step 204 for exposing the pattern of the reticle R onto the wafer W by the exposure apparatus of the above-described embodiment, device assembly step (including dicing process, bonding process, and packaging process) 205, inspection It is manufactured through step 206 and the like.

It is a figure which shows schematic structure of the exposure apparatus EX of this embodiment. It is a figure for demonstrating the control method of a stage. It is a figure for demonstrating other embodiment of the control method of a stage. It is a flowchart figure which shows an example of the manufacturing process of a microdevice. It is a figure for demonstrating the control method of the conventional stage.

Explanation of symbols

51, 53 ... Moving mirror 52, 54 ... Laser interferometer (measurement system)
61 ... Fixed mirror (position measuring unit, first measuring unit)
63 ... Fixed mirror (position measuring unit, second measuring unit)
65. Fixed mirror (position measurement unit)
62, 64, 66 ... Laser interferometer (measurement system)
AX ... Optical axis (optical path)
EL ... exposure light EX ... exposure apparatus R ... reticle (first substrate, mask)
PA ... Pattern RST ... Reticle stage (first stage, stage device, mask stage)
PL ... Projection optical system (optical element)
PK ... barrel P ... optical pivotal position W ... wafer (second substrate, photosensitive substrate)
WST ... Wafer stage (second stage, stage device, substrate stage)

Claims (14)

A first stage capable of moving in a first direction while holding a first substrate;
A second stage movable in the first direction while holding a second substrate;
An optical element portion disposed between the first stage and the second stage in a second direction intersecting the first direction;
Have
A stage for positioning the first substrate and the second substrate based on position measurement information in the first direction of the first stage, the second stage, and the optical element unit, and optical characteristics of the optical element unit. An apparatus control method comprising:
The position measurement units in the first direction in the optical element unit are spaced apart in the second direction and are arranged at a plurality of locations having a positional relationship that does not depend on the optical characteristics of the optical element unit. Control method of stage device.   The method of controlling a stage apparatus according to claim 1, wherein the position measurement of the first stage, the second stage, and the optical element unit is measured by independent measurement systems.   The position measurement unit includes a first measurement unit corresponding to the first stage and a second measurement unit corresponding to the second stage, from the optical pivot position of the optical element unit to the first measurement unit The ratio between the distance along the second direction and the distance along the second direction from the optical pivot position to the second measurement unit is set to a value different from the projection magnification of the optical element unit. The stage apparatus control method according to claim 1, wherein the stage apparatus is controlled.   The method of controlling a stage apparatus according to any one of claims 1 to 3, wherein the optical element section has an imaging characteristic of an erect image. The first stage, the optical element unit, and the second stage are arranged in this order along an optical path along which light passing through the optical element unit travels,
The method of controlling a stage apparatus according to claim 4, wherein the position measurement unit is arranged between an end portion on the incident side and an end portion on the exit side of the light in the optical element unit.   The method of controlling a stage apparatus according to claim 5, wherein the position measurement unit is arranged so as to be close to the first stage or the second stage. The optical element unit is a catadioptric imaging system,
The first measurement unit is installed between the installation position of the reflection unit in the optical element unit and the incident side end,
The method of controlling a stage apparatus according to claim 3, wherein the second measurement unit is installed between an installation position of the reflection unit and the emission side end. The optical element unit is a catadioptric imaging system,
The method for controlling a stage apparatus according to claim 3, wherein both the first measurement unit and the second measurement unit are installed between an installation position of the reflection unit and the incident side end. The optical element unit is a catadioptric imaging system,
4. The method of controlling a stage apparatus according to claim 3, wherein both the first measurement unit and the second measurement unit are installed between an installation position of the reflection unit and the emission side end. 5. A first stage capable of moving in a first direction while holding a first substrate;
A second stage movable in the first direction while holding a second substrate;
An optical element portion disposed between the first stage and the second stage in a second direction orthogonal to the first direction;
Have
A stage for positioning the first substrate and the second substrate based on position measurement information in the first direction of the first stage, the second stage, and the optical element unit, and optical characteristics of the optical element unit. An apparatus control method comprising:
The method of controlling a stage apparatus, wherein the position measuring unit in the first direction in the optical element unit is disposed at an optical pivotal position of the optical element unit.   The method for controlling a stage apparatus according to claim 10, wherein the position measurement of the first stage, the second stage, and the optical element unit is measured by independent measurement systems.   12. The method for controlling a stage apparatus according to claim 10, wherein the optical element section has an imaging characteristic of an inverted inverted image. A mask stage movable in the first direction while holding the mask;
A substrate stage movable in the first direction while holding a photosensitive substrate;
A projection optical system disposed between the mask stage and the substrate stage;
An exposure apparatus comprising:
The exposure apparatus according to claim 1, wherein the mask stage and the substrate stage are controlled by the control method of the stage apparatus according to any one of claims 1 to 12. 14. A device manufacturing method including a lithography process, wherein the exposure apparatus according to claim 13 is used in the lithography process.

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