Stage device, charged particle beam device, and vacuum device

Abstract

To provide a stage device, a charged particle beam device, and a vacuum device that suppress temperature fluctuations of a Z motor, enabling high-precision positioning and with a small leakage magnetic field.SOLUTION: The bottom surfaces of multiple magnets 502 are connected by a movable yoke 403 to form a magnetic circuit, and the multiple coils 501 are separated from the movable yoke 403 and fixed to a coil fixing portion 602, which is a heat dissipation path member, to suppress thermal deformation due to temperature fluctuations in the levitation portion. In other words, in Z-axis motor 506 used for gravity compensation and vertical thrust generation of the magnetic levitation stage, the movable yoke 403 is provided that covers the bottom surfaces of the multiple magnets 502 whose magnetic flux directions are vertical and different, and the multiple coils 501 are arranged separated from the movable yoke 403 with a gap between them.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a stage apparatus, a charged particle beam apparatus, and a vacuum apparatus. [Background technology]

[0002] Conventionally, technologies relating to magnetic levitation stages for accurately positioning and supporting device stages and wafers for semiconductor-related equipment have been known. Patent Document 1 describes the configuration of a magnetic levitation stage that positions a substrate without contact. This magnetic levitation stage mechanism uses a reluctance motor to perform gravity compensation using magnetic attractive force and to control position in the Z direction by increasing or decreasing the magnetic attractive force using a coil current. In Patent Document 1, a gap sensor is placed near the reluctance motor to control the amount of levitation and thereby perform positioning in the Z direction, thereby achieving contactless support of the levitation part. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-111714 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, in processes such as manufacturing, measuring, and inspecting semiconductor wafers, the aforementioned conventional stage devices are used to accurately position semiconductor wafers. Such stage devices are required to perform high-speed, high-precision positioning of semiconductor wafers. However, in a magnetic levitation stage device using a conventional reluctance motor as a Z motor (hereinafter also referred to as a Z-axis motor), such as that described in Patent Document 1, the coil current value in the reluctance motor fluctuates due to cable bending reaction forces from the cable transmitting signals and power to the levitation unit, variations in magnetization of the reluctance motor's permanent magnet, and gap variations due to component processing errors. This causes fluctuations in the heat generation of the Z motor, resulting in thermal deformation of the levitation unit and making accurate positioning difficult. Furthermore, the problem of leakage magnetic fields from the permanent magnets used for gravity compensation makes it difficult to apply the device to charged particle beam devices such as scanning electron microscopes.

[0005] The present disclosure provides a stage device, a charged particle beam device, and a vacuum device that are capable of highly accurate positioning and have a small leakage magnetic field by suppressing thermal deformation of the floating part due to temperature fluctuations. [Means for solving the problem]

[0006] One aspect of the present disclosure is a stage device comprising: a base; a stage that supports an object to be positioned on the base; and a Z-axis motor that magnetically levitates and positions the stage, wherein the Z-axis motor comprises a guide yoke provided on the base; and a mover provided on the stage so as to face the guide yoke in the vertical direction. The mover comprises a plurality of magnets arranged at intervals from each other in the horizontal direction so as to face the guide yoke in the vertical direction, the plurality of magnets having magnetic flux directions that are vertically opposite each other; a movable yoke that covers each of the plurality of magnets on the side opposite the guide yoke; and a plurality of coils arranged at intervals from each other in the horizontal direction at positions vertically spaced from the surface of each of the plurality of magnets facing the guide yoke, wherein the Z-axis motor magnetically levitates the stage by moving the mover in the vertical direction relative to the guide yoke using electromagnetic force between the plurality of magnets and the guide yoke. [Effects of the Invention]

[0007] According to the above aspect of the present disclosure, it is possible to provide a stage device, a charged particle beam device, and a vacuum device that are capable of suppressing thermal deformation of the floating part due to temperature fluctuations, enabling high-precision positioning, and positioning that can suppress magnetic field leakage and fluctuations. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a stage structure using a conventional rolling guide. [Figure 2] FIG. 1 is a perspective view showing a stage structure using a magnetic levitation guide. [Figure 3] FIG. 1 is a perspective view showing an example of the configuration of a magnetic levitation stage equipped with a Z motor according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a schematic cross-sectional view in the YZ plane of a magnetic levitation stage equipped with a Z motor according to an embodiment of the present disclosure. [Figure 5] FIG. 1 is a diagram illustrating the operating principle of a reluctance motor. [Figure 6] FIG. 1 is a diagram illustrating an example of the configuration of a conventional reluctance motor. [Figure 7] FIG. 1 is a diagram illustrating an example configuration of a reluctance motor according to an embodiment of the present disclosure. [Figure 8] FIG. 2 is a diagram illustrating details of a heat dissipation structure of a reluctance motor according to an embodiment of the present disclosure. [Figure 9] FIG. 1 is a diagram illustrating magnetic field leakage in a conventional reluctance motor. [Figure 10] 10A and 10B are diagrams illustrating the effect of reducing magnetic field leakage in a reluctance motor according to an embodiment of the present disclosure. [Figure 11] FIG. 1 is a configuration diagram of a reluctance motor according to an embodiment of the present disclosure, in which a position reference block is mounted. [Figure 12] FIG. 10 is a perspective view showing an example configuration of a magnetic levitation stage according to another embodiment of the present disclosure, in which a magnetic levitation guide is used for the upper shaft and a rolling guide is used for the lower shaft. [Figure 13] FIG. 10 is a schematic cross-sectional view in the YZ plane of a magnetic levitation stage according to another embodiment of the present disclosure, in which a magnetic levitation guide is used for the upper shaft and a rolling guide is used for the lower shaft. [Figure 14] FIG. 1 is a diagram showing a semiconductor measurement device that is an example of application to a charged particle beam device and a vacuum device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of a stage device, a charged particle beam device, and a vacuum device according to the present disclosure will be described with reference to the drawings. In the following description, a stage having a stroke of several hundred mm in one axis direction (X direction) or a stacked stage having a stroke of several hundred mm in two axes directions (X direction and Y direction) will be described.

[0010] Figure 1 is a diagram showing the configuration of a stage using a conventional rolling guide. Figure 1 shows an example of the configuration of a single-axis stage that uses rolling guides and moves in the X-axis direction. In this stage configuration, a top table 101 is guided by an X-guide 120 on a base 119 and moves in the X-axis direction. A sample 104, which is the object to be positioned, is mounted on a sample stage 103 placed on the top table 101. Because this stage configuration uses a contact-type rolling guide, the bending reaction force of wiring 130 such as a flat cable is supported by the guide rigidity.

[0011] Figure 2 shows an example of the configuration of a stage using a magnetic levitation guide (magnetic levitation stage). This is a configuration in which the X guide 120 of the stage in Figure 1 is replaced with a magnetic levitation guide. A magnetic levitation stage requires control of the position and attitude of the movable part with six degrees of freedom: displacement in the X, Y, and Z directions and rotation about the X, Y, and Z axes. Therefore, while the stage in Figure 1, which does not use magnetic levitation as a guide, requires only one motor as a driving element, the stage in Figure 2, which uses a magnetic levitation guide, requires six motor axes as driving elements. Specifically, while the X guide 120 in Figure 1 constrained displacement in the Y and Z directions, this function is replaced by the Y and Z motors.

[0012] In the magnetic levitation stage shown in Figure 2, the guide is a non-contact magnetic levitation guide, so the Z-direction bending reaction force of the wiring 130, such as a flat cable, is supported by the thrust of the Z motor. While the cable bending reaction force is generally small compared to the thrust required for accelerating and decelerating the stage, it is constantly applied, not only during stage movement but also when the stage is stopped. This forces a constant current to flow through the Z coil, causing heat generation in the Z motor. In particular, in a magnetic levitation stage, if the flat cable contains water-cooling piping for cooling the coils in the levitation section and sensors such as the scale head, the cable bending reaction force is greater than that of a stage using a rolling guide. Furthermore, the cable bending reaction force varies with position and varies from one stage to another. This leads to fluctuations in heat generation in the Z motor due to differences in the table position and machine, which in turn causes thermal deformation of the top table 101 and sample 104, resulting in variations in the field of view positioning accuracy.

[0013] FIG. 3 shows an example configuration of a magnetic levitation stage equipped with a Z motor according to an embodiment of the present disclosure. This magnetic levitation stage is a single-axis stage with a long stroke in the X direction and is equipped with a magnetic levitation guide that guides a top table 101 that moves in the X direction. The stage device 100 shown in FIG. 3 includes a linear motor that generates thrust in the X and Y directions along the longitudinal direction of a base 119, and a magnetic levitation guide 121 that outputs thrust in the Z direction. A water-cooled jacket 508 is mounted on a floating part that includes the top table 101 on which the sample 104 is mounted, and a bar mirror 102 is mounted on the top table 101 on which the sample 104 is mounted. The sample 104 is placed on a sample stage 103 installed on the top table 101, and the bar mirror 102 is irradiated with laser light from a laser interferometer (described later) and the reflected light is detected, thereby determining the positions of the top table 101 and the sample 104 in the X and Y directions. The water-cooled jacket 508 is installed to discharge or release (exhaust heat) heat generated from the coils of the levitation section and to cool the coils of the levitation section and sensors such as the scale head. Note that the water-cooled jacket 508 may also be a heat exhaust section using other cooling means. The other heat exhaust section may be capable of discharging or releasing (exhausting heat) heat generated from the coils of the levitation section and cooling them, and examples thereof include cooling jackets using other refrigerants, fins, Peltier elements, etc.

[0014] FIG. 4 shows a schematic cross-sectional view in the YZ plane of the magnetic levitation stage equipped with the Z motor according to the embodiment of the present disclosure shown in FIG. 3 . The levitation section is mainly composed of a water-cooled jacket 508 and a top table 101. A yoke 504 and a coil 503 of a linear motor (also referred to as an X- and Y-motor or an X- and Y-axis motor) that generates thrust in the X and Y directions are fixed to a base 119 (or to a magnetic levitation guide 121 attached thereto) and the water-cooled jacket 508, respectively. A coil (hereinafter also referred to as a Z coil) 501, a permanent magnet (hereinafter simply referred to as a magnet) 502, and a movable yoke (hereinafter also referred to as a back yoke) 403 of a Z motor 506 that generates thrust in the Z direction are fixed to the water-cooled jacket 508. A guide yoke 402 of the Z motor 506 that generates thrust in the Z direction is fixed to a base 119 (or to a magnetic levitation guide 121 attached thereto). The movable yoke 403 and the guide yoke 402 (or the magnetic levitation guide 121 on which they are provided) are made of a magnetic material such as SS400. That is, in order to magnetically levitate and position the levitation part constituted by the top table 101 and the like, the stage device 100 of this embodiment is provided with a Z motor 506 used to compensate for gravity of the levitation part and to generate a thrust in the vertical direction (Z direction). This Z motor 506 is constituted by a guide yoke 402 which is a stator fixed to the base 119, and a mover 505 which is constituted by a coil 501, a permanent magnet 502, and a movable yoke (back yoke) 403 which is fixed to a water-cooled jacket 508 so as to face the guide yoke 402 below in the vertical direction (Z direction) (details will be explained later). Water-cooled piping 507 through which water circulates as a coolant is embedded in the water-cooled jacket 508. Furthermore, the scale head 128 fixed to the bottom of the water-cooling jacket 508 measures the position and orientation of the scale plate 129 fixed to the bottom of the base 119 .

[0015] The operating principle of a reluctance motor is explained using Figure 5. The magnetic attraction force 401 between permanent magnet 105 and guide yoke 402, which faces permanent magnet 105 above in the vertical direction (Z direction), is used to compensate for the gravity of the levitation unit. Magnetic flux 108 is formed in a loop inside guide yoke 402 and back yoke 403. By passing current 106 through coil 107, the magnetic flux 108 increases or decreases, thereby increasing or decreasing magnetic attraction force 401 between permanent magnet 105 and guide yoke 402. This makes it possible to control the force in the Z direction acting on the levitation unit. As described above, a motor that controls magnetic attraction force 401 with coil current is generally called a reluctance motor. The use of a reluctance motor is effective for Z-axis motor 506 because it must maintain the gravity load of the levitation unit with zero current while offsetting the pitching moment associated with acceleration and deceleration in order to suppress motor heat generation and reduce field-of-view deviation due to thermal deformation.

[0016] FIG. 6 shows an example of the configuration of a conventional reluctance motor. In a reluctance motor (Z motor 506) with a conventional structure, a permanent magnet 502 is surrounded (bottom and side surfaces) by a movable yoke 403, and a coil 501 is placed on the upper surface of the movable yoke 403. The coil 501 is molded with molding resin 500. A coil fixing part 602 is connected to the lower surface of the movable yoke 403, and the movable yoke 403 is connected to a water-cooled jacket 508 via this coil fixing part 602. This structure provides a heat dissipation path 601 that guides heat 603 from the coil 501 to the water-cooled jacket 508 via the movable yoke 403 and the coil fixing part 602. The magnetic flux 108 generated by the permanent magnet 502 and the movable yoke 403 is increased or decreased by the current in the coil 501, and the change in the magnetic attractive force between the guide yoke 402 and the permanent magnet 502 is used as thrust in the Z direction. With this structure, coil 501 is fixed to movable yoke 403, which is made of a material such as SS400, which has relatively low thermal conductivity. This makes it difficult for heat generation 603 from coil 501 to escape to water-cooled jacket 508, which tends to increase the temperature of Z motor 506. This increases heat transfer to top table 101, resulting in greater field of view deviation. Furthermore, the temperature of permanent magnet 502, which is surrounded by movable yoke 403, tends to rise, creating the risk of thermal demagnetization of permanent magnet 502. When permanent magnet 502 is thermally demagnetized, the magnetic attraction force between it and guide yoke 402 decreases, and the amount of current in Z coil 501 increases to maintain gravity compensation for the levitation part, further increasing heat generation in Z coil 501 and further accelerating thermal demagnetization of permanent magnet 502, creating a vicious cycle.

[0017] FIG. 7 illustrates the structure of a temperature-stable reluctance motor according to an embodiment of the present disclosure, which addresses these issues. In this reluctance motor (Z motor 506), multiple permanent magnets 502 are arranged vertically below and facing guide yoke 402, with a gap (separation) between them in a horizontal direction perpendicular to the vertical direction. The bottom surfaces (the surfaces opposite the guide yoke 402) of the multiple permanent magnets 502 are connected to (covered by) a flat movable yoke 403, resulting in a compact magnetic circuit structure. The side surfaces and top surfaces of the multiple permanent magnets 502, other than the bottom surfaces, are exposed and not covered by the movable yoke 403. The movable yoke 403 may be formed of a single member, as shown in the figure, or multiple members, as long as it can cover the bottom surfaces of the multiple permanent magnets 502. The shape of the movable yoke 403 is not limited to that illustrated. The movable yoke 403, having the plurality of permanent magnets 502 fixed (connected) to its upper surface as described above, is fixed (connected) to a recessed portion provided in the coil fixing portion 602 in such a manner that the side surfaces of the permanent magnets 502 and the movable yoke 403 do not contact the coil fixing portion 602. In addition, in the reluctance motor (Z motor 506) having this structure, the plurality of coils 501 are arranged at positions spaced apart in the vertical direction from the upper surfaces (surfaces on the guide yoke 402 side) of the plurality of permanent magnets 502 (in other words, vertically separated from the plurality of permanent magnets 502 and the movable yoke 403) and spaced apart (separated) from each other in the horizontal direction. The plurality of coils 501 are molded with molded resin 500. The plurality of coils 501 molded with molded resin 500 are fixed to the upper surface formed around a recessed portion provided in the coil fixing portion 602 (portion to which the movable yoke 403 is fixed). That is, in a reluctance motor (Z motor 506) of this structure, multiple coils 501, multiple permanent magnets 502, and movable yoke 403 are arranged in this order from top to bottom in the vertical direction below guide yoke 402. Magnetic flux 108 generated by permanent magnet 502 and movable yoke 403 is formed in a loop shape inside guide yoke 402 and movable yoke 403, and as shown in the figure, the direction of magnetic flux 108 of each of the multiple permanent magnets 502 is vertical and opposite to each other (directions are different).Z coil 501 is separated from movable yoke 403 and permanent magnet 502 and fixed to coil fixing part 602 made of an aluminum material or the like having a higher thermal conductivity than movable yoke 403 and permanent magnet 502, and is connected to water-cooled jacket 508, which is a heat dissipation part that dissipates heat from Z coil 501, via coil fixing part 602, not via movable yoke 403 and permanent magnet 502, making it possible to provide an efficient heat dissipation path 601 from Z coil 501 to water-cooled jacket 508. In other words, improving the heat dissipation characteristics of Z motor 506 makes it possible to suppress a temperature rise in Z motor 506 and reduce field of view deviation. In addition, suppressing a temperature rise in permanent magnet 502 makes it possible to prevent thermal demagnetization.

[0018] FIG. 8 shows details of the heat dissipation structure of a reluctance motor according to an embodiment of the present disclosure. Note that, in FIG. 8, portions of molded resin 500 (such as the upper surface and inner side of each coil 501 and the portions between adjacent coils 501) are omitted to facilitate understanding of the structure. To enhance the heat dissipation effect to water-cooled jacket 508, it is preferable to arrange Z coils 501 (and permanent magnets 502) so that their longitudinal direction is the X direction, which is the moving direction of the stage, and arrange water-cooled jacket 508 in the Y direction (perpendicular to the direction in which Z coils 501 are arranged) relative to Z coils 501, thereby shortening the heat transfer path from each Z coil 501 to the Y direction. By changing the mounting height of movable yoke 403 relative to coil fixing portion 602, the magnetic attraction force of permanent magnet 502 to guide yoke 402 can be fine-tuned, and specification changes, such as changes in the mass of the levitation portion, can be easily accommodated.

[0019] Next, the effect of reducing the leakage magnetic field of the Z motor of the present disclosure will be described.

[0020] Using Figure 9, we will explain the occurrence of leakage magnetic fields in a conventional reluctance motor. In a conventional reluctance motor, in addition to the loop of main magnetic flux 108, magnetic short circuit 108A occurs, where magnetic flux circulates within movable yoke 403. This weakens the loop of main magnetic flux 108, reducing the magnetic attractive force and requiring larger permanent magnet 502 to compensate. Increasing the size of permanent magnet 502 increases the leakage magnetic field, which requires larger movable yoke 403 as well, resulting in an increase in moving mass. This then leads to a vicious cycle of increasing size, which requires even larger permanent magnet 502 to compensate for the increased magnetic attractive force of the moving part, resulting in reduced maneuverability due to the increased mass of the moving part.

[0021] The effect of reducing magnetic field leakage in a reluctance motor according to an embodiment of the present disclosure will be described using FIG. 10 . In the structure of Z motor 506 according to this embodiment, there is no movable yoke 403, which is a magnetic material, next to permanent magnet 502. This prevents the magnetic short circuit shown in FIG. 9 and allows for the miniaturization of permanent magnet 502. In this reluctance motor, guide yoke 402 is located above permanent magnet 502, but movable yoke 403, which is relatively close to permanent magnet 502, does not cover the upper side of permanent magnet 502. Therefore, the upward leakage magnetic field does not depend on the shape of movable yoke 403, but only on the thickness of permanent magnet 502. Therefore, in Z motor 506 according to this embodiment shown in FIG. 10 , permanent magnet 502 can be made smaller than in the conventional Z motor shown in FIG. 9 , making it possible to suppress the leakage magnetic field in the Z direction where sample 104 is located. This makes it suitable for a sample stage in a charged particle beam device such as a scanning electron microscope.

[0022] The mounting layout of the Z motors and position reference blocks according to an embodiment of the present disclosure will be described using FIG. 11 . Four movers 505 of Z motors 506, each consisting of a permanent magnet 502, a movable yoke 403, and a Z coil 501, are mounted around a water-cooling jacket 508 and control the attitude of the levitation unit around the X and Y axes. To improve the reproducibility of the levitated attitude, the magnetic levitation stage performs an initialization operation during levitation initialization, in which a position reference block 701 is pressed against the underside of a guide yoke 402 (the stator of the Z motor 506) to position the block. Furthermore, the magnetic attractive force of the Z motor 506, which compensates for gravity, varies depending on the distance 702 between the permanent magnet 502 and the guide yoke 402 in the Z direction. The difference between the magnetic attractive force and gravity must be compensated for by the thrust of the Z motor 506, resulting in an offset component in the current value of the Z coil 501. In other words, to reduce heat generation in the Z motors 506, it is necessary to stabilize the gravity compensation force of the four Z motors 506 and improve the reproducibility of the attitude during the initialization operation. Therefore, at least three position reference blocks 701 are arranged near or in the vicinity of Z motor 506 to define the distance (distance in the Z direction) between mover 505 of Z motor 506 (particularly permanent magnet 502) and guide yoke 402, which is the stator of Z motor 506, thereby creating a structure in which a plane is defined with high reproducibility at at least three points. To suppress changes in the reference plane during initialization, it is recommended that position reference blocks 701 be made of resin to prevent scratches on the lower surface of guide yoke 402. Position reference blocks 701 may be installed on coil fixing portion 602 near or in the vicinity of Z motor 506, as shown, or on guide yoke 402. In the case of a vacuum device (FIG. 14), it is recommended that PPS, which has good processability and outgassing properties, be used as the resin material.

[0023] FIG. 12 shows an example of the configuration of a stacked stage that uses a magnetic levitation guide for the X axis and a rolling guide for the Y axis. FIG. 12 shows an example of a configuration in which the single-axis magnetic levitation stage shown in FIG. 3 is used as the upper axis, and the stage using a single-axis rolling guide shown in FIG. 1 is used as the lower axis. In stage device 200 shown in FIG. 12, the portion corresponding to base 119 in FIG. 3 is Y table 109, which is guided by Y guide 110 so that it can move in the Y direction. This makes it possible to configure a magnetic levitation stage with long strokes in both the X and Y directions. Note that a low-cost rolling guide may be used for Y guide 110. It is also possible to configure a stacked stage in which Y guide 110 is a magnetic levitation guide and both the X and Y axes are magnetically levitated guides.

[0024] Figure 13 shows a schematic cross-sectional view in the YZ plane of the stack-type stage shown in Figure 12. This is an example where the upper axis is a magnetic levitation guide and the lower axis is a rolling guide. This stage device 200 is configured by disposing rolling Y guide 110 below Y table 109, which is U-shaped when viewed in the X direction.

[0025] Finally, an embodiment of a charged particle beam device and a vacuum device according to the present disclosure will be described with reference to Fig. 14. Fig. 14 is a schematic cross-sectional view of a semiconductor measurement device that is an embodiment of a charged particle beam device and a vacuum device that includes a stage device equipped with a magnetic levitation stage having a temperature-stable Z motor according to the present disclosure.

[0026] A semiconductor measuring apparatus 950, which is one embodiment of the charged particle beam device and vacuum device according to the present disclosure, includes a stage apparatus 200 (FIGS. 12 and 13) that positions the target object 104, and a vacuum chamber 951 that houses the stage apparatus 200. Note that the stage apparatus 100 (FIG. 3, etc.) may be used instead of the stage apparatus 200. The semiconductor measuring apparatus 950 of this embodiment is, for example, a length-measuring SEM that is an application of a scanning electron microscope (SEM).

[0027] The semiconductor measuring device 950 includes, for example, a stage device 200, a vacuum chamber 951, an electron optical system barrel 952, a vibration-damping mount 953, a laser interferometer 954, and a controller 955. The vacuum chamber 951 houses the stage device 200, and its interior is depressurized by a vacuum pump (not shown) to create a vacuum state at a pressure lower than atmospheric pressure. The vacuum chamber 951 is supported by the vibration-damping mount 953.

[0028] The semiconductor measuring device 950 positions an object 104 such as a semiconductor wafer using a stage device 200 housed in a vacuum chamber 951, irradiates an electron beam from an electron optical system lens barrel 952 onto the object 104, captures an image of a pattern on the object 104, measures the line width of the pattern, and evaluates its shape accuracy. The stage device 200 measures the position of the bar mirror 102 by irradiating a laser beam 956 onto the bar mirror 102 with a laser interferometer 954 and detecting the reflected light, and the scale head 128 measures the position of a scale plate 129 fixed to a Y table 109. The position of the object 104 such as a semiconductor wafer held on a sample stage 103 of a top table 101 is controlled by a controller 955.

[0029] The semiconductor measuring apparatus 950 according to this embodiment includes a stage device 200 with a small temperature fluctuation of the Z motor 506, thereby reducing field of view deviation caused by thermal deformation due to heat generated by the motor when positioning the object 104, such as a semiconductor wafer, and suppressing magnetic field leakage. This improves the field of view positioning accuracy of the semiconductor measuring apparatus 950 as a charged particle beam apparatus. Furthermore, because the levitation mechanism of the stage device 200 is a magnetic levitation type, it can be easily applied to the semiconductor measuring apparatus 950, which is a vacuum apparatus, and can achieve excellent effects such as reduced contamination and heat generation. The charged particle beam apparatus and vacuum apparatus of the present disclosure are not limited to semiconductor measuring apparatuses.

[0030] As explained above, the stage device (100, 200) according to this embodiment is a stage device comprising a base (119, 109), a stage (top table 101) that supports an object 104 to be positioned on the base, and a Z-axis motor 506 that magnetically levitates and positions the stage, the Z-axis motor 506 comprising a guide yoke 402 (a stator) provided on the base, and a mover 505 provided on the stage so as to face the guide yoke 402 in the vertical direction, the mover 505 being a plurality of magnets 502 that are arranged at intervals from one another in the horizontal direction so as to face the guide yoke 402 in the vertical direction, and the direction of the magnetic flux 108 of each is vertical and perpendicular to the direction of the magnetic flux 108 of each magnet 502. a movable yoke 403 covering the surface (bottom surface) of each of the magnets 502 opposite to the guide yoke 402 side; and a plurality of coils 501 arranged at intervals from each other in the horizontal direction, at positions spaced apart in the vertical direction from the surface (top surface) of each of the magnets 502 facing the guide yoke 402. When a current is passed through the plurality of coils 501 (when the plurality of coils 501 are energized), the Z-axis motor 506 magnetically levitates the stage (relative to the base) by moving the mover 505 in the vertical direction relative to the guide yoke 402 due to electromagnetic force (magnetic attraction force 401) between the plurality of magnets 502 and the guide yoke 402.

[0031] The mover 505 is arranged below the guide yoke 402, with the plurality of coils 501, the plurality of magnets 502, and the moveable yoke 403 arranged in this order from above in the vertical direction.

[0032] The movable yoke 403 covers only the surface (bottom surface) of each of the magnets 502 opposite to the guide yoke side.

[0033] The multiple coils 501 are connected to a coil fixing part 602 having a higher thermal conductivity than the movable yoke 403 (and the multiple magnets 502), and are connected to a heat dissipation part (such as a water-cooled jacket 508) that dissipates heat generated by the multiple coils 501 via the coil fixing part 602, not via the movable yoke 403 (and the multiple magnets 502).

[0034] The movable yoke 403 is connected to the coil fixing portion 602 , and the plurality of magnets 502 (bottom surfaces thereof) are connected to the movable yoke 403 (top surface thereof) without coming into contact with the coil fixing portion 602 .

[0035] The plurality of magnets 502 and the plurality of coils 501 are arranged in a line in the moving direction of the stage, and the heat dissipation unit is arranged in a direction perpendicular to the line-up of the plurality of magnets 502 and the plurality of coils 501.

[0036] That is, in this embodiment, the bottom surfaces of multiple magnets 502 are connected by movable yoke 403 to form a magnetic circuit, and multiple coils 501 are separated from movable yoke 403 and fixed to coil fixing section 602, which is a heat dissipation path member, thereby suppressing thermal deformation due to temperature fluctuations in the levitation section, thereby providing a stage device, charged particle beam device, and vacuum device that allows high-precision positioning and has small leakage magnetic field. In other words, in Z-axis motor 506 used for gravity compensation and vertical thrust generation of the magnetic levitation stage, movable yoke 403 is provided that covers the bottom surfaces of multiple magnets 502 whose magnetic flux directions are vertical and different, and multiple coils 501 are arranged separated from movable yoke 403 with a gap between them.

[0037] According to this embodiment, it is possible to provide a stage device, a charged particle beam device, and a vacuum device that can suppress thermal deformation of the floating part due to temperature fluctuations, enable high-precision positioning, and enable positioning that can suppress magnetic field leakage and fluctuations.

[0038] Although an embodiment of the present invention has been described in detail above using the drawings, the specific configuration is not limited to this embodiment, and even if there are design changes and the like within the scope that does not deviate from the gist of the present invention, they are also included in the present invention. [Explanation of symbols]

[0039] 100, 200 stage equipment 101 Top Table (Stage) 102 Bar Mirror 103 Sample stage 104 Sample (object) 105 Permanent Magnets 106 Current 107 Coil 108 Magnetic Flux 108A Magnetic Short 109 Y table (base) 110 Y Guide 119 Base 120 X Guide 121 Magnetic Levitation Guide 128 scale head 129 Scale Plate 130 Wiring 401 Magnetic attraction force 402 Guide Yoke 403 Movable yoke (back yoke) 500 mold resin 501 Z-axis motor coil 502 Z-axis motor permanent magnet 503 X and Y axis motor coils 504 X and Y axis motor yokes 506 Z-axis motor (Z motor) 507 Water-cooled piping 508 Water cooling jacket (heat exhaust section) 601 Heat dissipation path 602 Coil fixing part 603 Coil heat generation 701 Position Reference Block 702 Distance between permanent magnet and guide yoke

Claims

1. A stage device comprising: a base; a stage that supports an object to be positioned on the base; and a Z-axis motor that magnetically levitates and positions the stage, the Z-axis motor includes a guide yoke provided on the base, and a mover provided on the stage so as to face the guide yoke in the vertical direction; The mover is a plurality of magnets arranged at intervals in the horizontal direction so as to face the guide yoke in the vertical direction, the magnets having magnetic fluxes directed in the vertical direction and opposite to each other; a movable yoke covering a surface of each of the plurality of magnets opposite to the guide yoke side; a plurality of coils arranged at intervals from each other in the horizontal direction at positions spaced apart in the vertical direction from the surfaces of the plurality of magnets facing the guide yoke, The Z-axis motor magnetically levitates the stage by moving the movable element in a vertical direction relative to the guide yoke using electromagnetic force between the multiple magnets and the guide yoke.

2. 2. The stage device according to claim 1, wherein the movable element is arranged below the guide yoke in the following order from above in the vertical direction: the plurality of coils, the plurality of magnets, and the movable yoke.

3. 2. The stage device according to claim 1, wherein the movable yoke covers only the surface of each of the plurality of magnets opposite to the guide yoke side.

4. 2. The stage device according to claim 1, wherein the plurality of coils are connected to a coil fixing portion having a higher thermal conductivity than the movable yoke, and are connected to a heat dissipation portion that dissipates heat generated from the plurality of coils via the coil fixing portion, without going through the movable yoke.

5. 5. The stage device according to claim 4, wherein the movable yoke is connected to the coil fixing portion, and the plurality of magnets are connected to the movable yoke without contacting the coil fixing portion.

6. 5. The stage device according to claim 4, wherein the plurality of magnets and the plurality of coils are arranged in a line in the moving direction of the stage, and the heat dissipation unit is arranged in a direction perpendicular to the line in which the plurality of magnets and the plurality of coils are arranged.

7. 2. A stage device according to claim 1, wherein at least three position reference blocks that define the distance between the mover and the guide yoke are arranged around the Z-axis motor.

8. A charged particle beam device comprising the stage device according to claim 1 .

9. A vacuum apparatus comprising the stage apparatus according to claim 1.

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