JP2009117803A - Driving apparatus and exposure apparatus, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving apparatus and exposure apparatus capable of improving the rigidity and durability of a guide while maintaining the moving performance of a movable body by an improvement in the structure of the guide, and to provide a device manufacturing method. <P>SOLUTION: A guide includes a brittle material layer and a magnetically attracting magnetic body, e.g., a metal layer. A recess and a projection having at least one set of high level and low level (to be referred to as a step difference hereinafter) are formed on the magnetically attracting metal layer. The brittle material layer is made of, e.g., a sprayed ceramic material and covers at least the recess formed on the magnetically attracting metal layer. A movable body moves as it levitates above the surface of the brittle material layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a driving apparatus, an exposure apparatus including the driving apparatus, and a device manufacturing method for manufacturing a device using the driving apparatus.

  An exposure apparatus is used in a lithography process for manufacturing a device such as a semiconductor device, more specifically, in an exposure process. The exposure apparatus is configured to project the mask pattern held on the mask stage onto the wafer held on the wafer stage by a projection optical system and to expose the wafer.

A stage device is used to hold and position a wafer or mask. The stage apparatus includes a stage including a chuck that holds a wafer and a mask, and a drive mechanism that drives the stage. The drive mechanism can include, for example, a movable body that moves with the stage, a guide that supports or guides the movable body, and an actuator such as a linear motor that generates a driving force. The movable body can move while forming a substantially constant gap between the guide and the guide due to the flying force of the air pad and the attractive force of the pressurizing magnet.
JP-A-9-5463 JP 2000-260691 A

  Conventionally, the guide is made of cast iron, and the surface thereof is nickel-phosphorous-plated to prevent the surface from being oxidized and to increase the hardness and surface accuracy.

  However, in the air guide mechanism, air may be blocked during the movement of the stage, so that the air pad and the guide may come into contact with each other and the guide side may be damaged. In addition, there is a possibility that the guide may be damaged when the stage moves in a state where small dust or the like is present between the air pad and the guide. When the metal material mentioned above is used for the material of a guide, if the surface of a guide is damaged, the surface of a metal material will rise. When the stage or the like moves along the surface of each guide in this state, rubbing occurs between the raised guide and the air pad.

  Therefore, the motion accuracy of the air guide mechanism is impaired, or the dynamic characteristics of the air guide mechanism are fluctuated, and the control performance for the moving stage may be significantly reduced. In addition, if the product is used for a long time in such a state, there are cases where the air pad may be gradually damaged, resulting in a fatal injury, and in extreme cases, the air pad may be damaged, making the stage inoperable. We had difficulties in terms of sex.

  By the way, Patent Document 1 discloses an example in which a stage surface plate is made of an alumina ceramic material. Alumina ceramics is a non-magnetic material and cannot be pre-magnetized, so pre-loading with a vacuum pad is used. In a configuration using a pressure pad with a vacuum pad, in order to generate the same attractive force as the pressure magnet, a larger pad area is required than the area of the pressure magnet, and in addition to the pressure air line A vacuum airline needs to be configured. Therefore, there is a drawback that the mounting of the back surface of the fine movement stage constituting the pad and the piping of the entire stage apparatus are complicated. Moreover, in order to obtain a suction force equivalent to that of the pressurizing magnet, a high vacuum vacuum air is required. Therefore, a high vacuum air line must be drawn in the exposure apparatus.

  Patent Document 2 discloses an example in which ceramic is sprayed on a stage surface plate. However, when a pressurized magnet is used, the ceramic layer must be thinly formed. There is a drawback that the rigidity of the air pad running surface cannot be maintained. Further, if the thickness of the magnet pressurizing surface and the air pad sliding surface is changed, the number of machining steps for the ceramic layer must be increased, resulting in deterioration of accuracy and cost.

  The present invention has been made in view of the above-described problems. For example, a drive device that improves the rigidity and durability of the guide while maintaining the moving performance of the movable body by improving the structure of the guide. And an exposure apparatus and a device manufacturing method.

  In order to achieve the above object, one embodiment of the present invention is a driving device that drives a movable body supported by a guide, and the guide is formed of a magnetic material and has a recess and a protrusion on a side that guides the movable body. And a brittle substance layer that covers at least the concave portion of the support and forms a guide surface that guides the movable body, and the movable body is an air pad that floats from the guide surface And a magnet for obtaining an attractive force between the support and the support.

  Another embodiment of the present invention is an exposure apparatus that projects an original pattern held on an original stage onto a substrate held on the substrate stage by a projection optical system and exposes the substrate, the driving apparatus as described above The drive device is configured to drive at least one of the original stage or the substrate stage in accordance with the movement of the movable body of the drive device.

  A device manufacturing method according to an aspect of the present invention includes a step of exposing a substrate by the exposure apparatus as described above, and a step of developing the substrate.

  According to the present invention, for example, by improving the structure of the guide, the rigidity and durability of the guide can be improved while maintaining the moving performance of the movable body.

  Embodiments of a driving apparatus, an exposure apparatus, and a device manufacturing method according to the present invention will be described below with reference to the accompanying drawings. In this embodiment, the stage apparatus according to the present invention is applied to a substrate stage apparatus (wafer stage apparatus 17) in an exposure apparatus that holds a substrate.

  Hereinafter, with reference to FIGS. 1 to 7, embodiments of a driving apparatus, an exposure apparatus, and a device manufacturing method according to the present invention will be described.

  FIG. 1 is a view showing an example of a schematic configuration of an exposure apparatus 15 according to the present embodiment.

  The exposure device 15 has a function of projecting a pattern formed on the mask M onto the wafer P coated with a photosensitive agent and transferring the pattern onto the photosensitive agent on the wafer P. The exposure apparatus 15 includes a light source 14, an illumination optical system 13, a mask stage apparatus 12, a projection optical system 16, a wafer stage apparatus 17, and the like. Here, the Z axis in the direction parallel to the optical axis of the projection optical system 16, the Y axis in the direction perpendicular to the plane of FIG. 1 in the plane perpendicular to the optical axis, and the plane of FIG. 1 in the plane perpendicular to the optical axis. And the X axis are set in parallel to each other.

  The mask stage (also referred to as an original stage) device 12 holds a mask (also referred to as an original) M. The light source 14 generates a light beam L used for exposure of the wafer P. As the light source 14, for example, an excimer laser is suitable. The light beam L emitted from the light source 14 is reflected by the reflection mirror 18 and provided to the illumination optical system 13. The illumination optical system 13 illuminates the mask M. The light beam L emitted from the illuminated mask M forms an image on a wafer (also referred to as a substrate) P through the projection optical system 16. A pattern image of the mask M is formed on the surface of the wafer P. By driving a wafer stage (also referred to as a substrate stage) 8, the wafer P is stepped two-dimensionally. Then, the pattern of the mask M is sequentially transferred to each shot area of the wafer P by sequentially exposing each shot area of the wafer P while performing step movement.

  The wafer stage 8 holds the wafer P and is driven in directions perpendicular to each other (three-dimensional directions of X, Y, and Z). A movable mirror 17 a is fixed on the wafer stage 8. The movable mirror 17a is used for detecting the position of the wafer stage 8 (that is, the wafer P) by a laser interferometer (not shown).

  FIG. 2 is a view showing an example of an external perspective view of the wafer stage device 17. The wafer stage device 17 includes a vibration isolation device 1, a surface plate 2, a Y guide 3, a Y driving linear motor 4, an X guide 5, an X driving linear motor 6, a wafer chuck 7, and the like. Here, the movable mirror 17a shown in FIG. 1 described above includes a Y movable mirror and an X movable mirror. Using the Y moving mirror and the X moving mirror, the positions of the wafer stage 8 in the X direction and the Y direction are detected.

  In addition, the vibration isolator 1 is disposed between the factory floor where the exposure apparatus 15 is installed and the surface plate 2. The vibration isolator 1 includes a pneumatic damper, a linear motor, and the like, and controls vibrations applied to the surface plate 2 and vibrations of the exposure apparatus 15 due to movement of the wafer stage 8.

  FIG. 3 is a diagram illustrating an example of an enlarged cross section of the Y guide 3.

  The Y guide 3 includes a ceramic layer 3a, which is a brittle material layer, and an absorptive metal layer 3b.

  The magnetic absorption metal layer 3 b is made of a magnetic material having magnetic absorption, for example, a metal material, and constitutes a support for the Y guide 3. The magnetic absorption metal layer 3b is made of, for example, a low thermal expansion casting and has sufficient rigidity. Note that the magnetic absorption metal layer 3b may have a can structure. The magnetic absorption metal layer 3b is provided with a concavo-convex shape on the movable body, that is, on the side where the X guide 5 is supported by the Y guide 3 and moves in the present embodiment.

  The magnetic absorption metal layer 3 b has irregularities on the guide surface side that supports or guides the X guide 5. The ceramic layer 3a is formed on the metal layer 3b so as to cover the metal layer 3b. The surface of the ceramic layer 3 a functions as a guide surface that supports or guides the X guide 5. The ceramic layer 3a is formed of, for example, sprayed ceramics.

  The X guide 5 floats on the Y guide 3 to a predetermined height by an air guide mechanism (not shown), and freely moves in the Y direction by the Y drive linear motor 4. The wafer stage 8 floats on the X guide 5 to a predetermined height by an air guide mechanism (not shown). A stator of an X drive linear motor 6 is fixed to the X guide 5, and a mover of the X drive linear motor 6 is fixed to the wafer stage 8. The wafer stage 8 is freely moved in the X direction by the X driving linear motor 6. That is, the X guide 5 and the Y guide 3 are moved by both linear motors (4, 6), and the wafer stage 8 is driven in accordance with the movement.

  Here, an example of a procedure for manufacturing the Y guide 3 in the wafer stage device 17 having the above configuration will be described with reference to FIGS.

  First, an absorptive metal layer 3b of the Y guide 3 is formed. As shown in FIG. 4, the metal layer 3b is formed with a concavo-convex shape having at least one set of height differences (hereinafter referred to as steps) on the surface. The step is, for example, 20 μm or more. Depending on the device configuration, the step may be set to 50 μm or more, or 100 μm or more, for example. Although details will be described later, the uneven shape is provided so as to be opposed to the pressurizing magnet and the air pad, respectively. Therefore, if the step is large, the ceramic layer 3a facing the air pad can be thermally sprayed, so that the rigidity of the ceramic layer 3a, Durability can be increased.

  Here, the concavo-convex shape formed in the metal layer 3 b is arranged so that the concave portions (23 a to 23 c) face the air pads (20 a to 20 c) in the X guide 5 as shown in FIG. 5. Furthermore, this uneven shape is arranged so that the convex portions (22a, 22b) face the pressurizing magnets (21a, 21b) in the X guide 5. This arrangement is adopted by thinning the ceramic layer 3a at a position facing the pressurizing magnet (21a, 21b) and thickening the ceramic layer 3a at a position facing the air pads (20a to 20c), thereby attracting the magnet. This is to increase the rigidity while increasing the rigidity.

  Further, the convex portions (22a, 22b) and the concave portions (23a-23c) in the concavo-convex shape are formed in, for example, a rectangular shape, and the longitudinal direction thereof is formed along the moving direction of the X guide 5, respectively. The reason for adopting this configuration is to keep the levitation force by the air pad and the attraction force obtained by the pressurizing magnet constant and to move the X guide 5 stably.

  Subsequently, the ceramic layer 3a is thermally sprayed on the metal layer 3b so as to cover the uneven shape. As shown in FIG. 6, the ceramic layer 3a is sprayed over the metal layer 3b by, for example, 200 μm or more. After this thermal spraying, the ceramic layer 3a is subjected to surface polishing after sealing, and the ceramic layer 3a is processed into the same plane. In the planar polishing, as shown in FIG. 7, the thickness of the ceramic layer 3a at the convex portion of the magnetically absorbing metal layer 3b is set to about 50 μm, for example. Thus, when the guide surface on the side that supports the X guide 5 is formed as a flat surface, the processing time is shortened and the cost can be suppressed. In addition, the accuracy of flatness can be improved. Incidentally, the plane referred to here may be a flatness that does not impair the function as a guide, and is not necessarily a complete plane.

  In addition, in this embodiment, although the convex part and recessed part of the metal layer 3b are covered with the ceramic layer 3a, if the function as a guide is not impaired, it shall be set as the structure which covers only a recessed part with the ceramic layer 3a. Is also possible.

  In this embodiment, ceramic is used as an example of the brittle substance layer. However, the ceramic layer is not limited to ceramic, and has a certain degree of hardness (preferably a hardness of 7 or more), and has sufficient rigidity to be used as a guide. I just need it. For example, glass, diamond, carbon composite material, stone material and the like may be used.

  The main point of using a brittle substance layer on the surface of the metal layer is to prevent direct contact between the metal layer and the air pad, etc., and to prevent swell due to contact with the air pad etc. as in the case of metal. . Therefore, it goes without saying that materials that can be used as the brittle substance layer are not limited to those shown in the above embodiments unless departing from the gist of the present invention.

  The configuration and manufacturing procedure of the X guide 5 are the same as the configuration and manufacturing procedure of the Y guide 3 described with reference to FIGS. 3 and 4 to 7 described above, and thus the description thereof is omitted.

  Moreover, although the manufacturing procedure of Y guide 3 was demonstrated using the said FIGS. 4-7, this is an example to the last, For example, in the said example, although there are two convex parts, it is one place or three places or more. Needless to say, it may be.

  In the above description, the configuration of the X guide 5 and the Y guide 3 in the wafer stage device 17 and the manufacturing procedure thereof have been described. However, the configuration of the X guide 5 and the Y guide 3 in the wafer stage device 17 is similar to the mask stage device described above. 12 can also be applied. Further, this configuration is not necessarily applied to the wafer stage device 17 and may be applied only to the mask stage device 12. That is, the above-described configuration can be applied to at least one of the wafer stage device 17 and the mask stage device 12. Needless to say, the present invention can be similarly applied to a device such as the wafer stage device 17.

  The device includes a step of exposing a substrate (wafer, glass plate, etc.) coated with a photoresist (photosensitive agent) using the exposure apparatus 15, a step of developing the exposed substrate, and other known steps. It is manufactured by going through.

  As described above, according to the above-described embodiment, for example, when ceramics are used as the brittle material layer, the ceramic layer is thermally sprayed so that it is limited to a size that is a restriction on the use of a normal ceramic material. Disappears. Therefore, it is possible to appropriately cope with an exposure apparatus that tends to be further increased in size in the future. Further, for example, since ceramics are used only in necessary portions, the cost of the member can be greatly reduced.

  In addition, for example, the guide surface is made of a brittle substance (for example, ceramics), so even if the guide surface is damaged, even if the swell is generated or the air guide mechanism gets stuck with dust, it is work hardened. No excitement due to. Therefore, rubbing does not occur between the air guide mechanism. Therefore, the performance of the air guide mechanism can be maintained for a long time without being damaged. For example, when ceramics are used as the brittle substance layer, the thickness of the ceramic layer can be changed according to the purpose because the unevenness processing is performed before the ceramics are sprayed.

  The present invention can be widely applied to an exposure apparatus for manufacturing a liquid crystal display device manufacturing apparatus, a semiconductor manufacturing exposure apparatus, a thin film magnetic head, a photographing element (CCD), or a mask used in a projection exposure apparatus.

  In addition to the above devices, in a device for moving a workpiece such as a length measuring device, it is used for a moving mechanism and a positioning mechanism of the workpiece.

It is a figure which shows an example of schematic structure of the exposure apparatus 15 concerning this embodiment. It is a figure which shows an example of the external appearance perspective view of the wafer stage apparatus 17 shown in FIG. It is a figure which shows an example of the expanded cross section of the Y guide 3 shown in FIG. It is a 1st figure which shows an example of the procedure at the time of manufacturing the Y guide 3 shown in FIG. It is a 2nd figure which shows an example of the procedure at the time of manufacturing the Y guide 3 shown in FIG. FIG. 10 is a third diagram illustrating an example of a procedure for manufacturing the Y guide 3 illustrated in FIG. 2. FIG. 10 is a fourth diagram illustrating an example of a procedure for manufacturing the Y guide 3 illustrated in FIG. 2.

Explanation of symbols

M Mask P Wafer L Ray 1 Vibration isolation device (mount)
2 Surface plate 3 Y guide 3a Ceramic layer 3b Metal layer 4 Y drive linear motor 5 X guide 6 X drive linear motor 7 Wafer chuck 8 Wafer stage 12 Mask stage device 13 Illumination optical system 14 Light source 15 Exposure device 16 Projection optical system 17 Wafer stage device 17a Moving mirror 18 Reflecting mirror

Claims (8)

A driving device for driving a movable body supported by a guide,
The guide is
A support body made of a magnetic material and having a concave portion and a convex portion on the side that guides the movable body, and a brittle substance layer that covers at least the concave portion of the support body and forms a guide surface that guides the movable body. And
The movable body is
A driving apparatus comprising: an air pad for floating from the guide surface; and a magnet for obtaining an attractive force between the support and the support. The concave portion and the convex portion are rectangular.
The driving device according to claim 1, wherein the concave portion and the convex portion are formed such that a longitudinal direction thereof is along a moving direction of the movable body. The driving device according to claim 1, wherein the brittle substance layer covers the concave portion and the convex portion. The said recessed part is arrange | positioned so that the air pad of the said movable body may be opposed, and the said convex part is arrange | positioned so that the magnet of the said movable body may be opposed. The Claim 1 thru | or 3 characterized by the above-mentioned. Drive device. The driving device according to any one of claims 1 to 4, wherein a surface of the brittle substance layer as the guide surface is a flat surface. The drive device according to any one of claims 1 to 5, wherein a height difference between the concave portion and the convex portion is formed to be 20 µm or more. An exposure apparatus that projects a pattern of an original held on an original stage onto a substrate held on a substrate stage by a projection optical system and exposes the substrate,
A drive device according to any one of claims 1 to 6, comprising:
The driving device is configured to drive at least one of the original stage or the substrate stage according to the movement of the movable body of the driving device.
An exposure apparatus characterized by that. A device manufacturing method comprising:
Exposing the substrate with the exposure apparatus according to claim 7;
Developing the substrate;
A device manufacturing method comprising:

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