Scanning stage

Abstract

To provide a compact scanning stage that allows a device to scan the surface of a large-diameter object.SOLUTION: A scanning stage 10 includes an X-Y stage 21, an apparatus 17 fixed to a common X-Y-Z coordinate system with the X-Y stage 21, a rotating stage 22 mounted on the X-Y stage 21 and holding and rotating an object to be scanned 15, a first drive unit 11 that drives the X-Y stage 21 such that one of a plurality of areas (A, B, C, D) obtained by equally dividing the object to be scanned 15 with respect to the rotation center point O of the rotating stage 22 is set as a scanning area R, and the input / output axis 18 of the apparatus 17 scans this scanning area R, and a second drive unit 12 that drives the rotating stage 22 so that the unscanned area (A, B, C, D) is positioned in the scanning area R.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a scanning stage for scanning the surface of a scanning object. [Background technology]

[0002] In semiconductor manufacturing, there is a process for inspecting the patterns formed on wafers. During this inspection process, abnormalities and defects in highly integrated semiconductor integrated circuits are detected. To inspect all patterns on the wafer, the wafer is placed on an XY stage and scanned from one end to the other by a detector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-156392 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in order to increase the number of elements per wafer and improve productivity, wafers have become larger in diameter, with 12 inches (approximately 300 mm) being the mainstream at present.As mentioned above, if the entire surface of a substrate such as a wafer is to be scanned by moving only the XY stage, there is an unavoidable problem of having to increase the size of the XY stage.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a compact scanning stage that allows an apparatus to scan the surface of a scanning target having a large diameter. [Means for solving the problem]

[0006] The scanning stage of the present invention is characterized by comprising an XY stage, equipment fixed to a coordinate system common to the XY stage, a rotating stage mounted on the XY stage to hold and rotate an object to be scanned, a first drive unit that drives the XY stage so that one of a plurality of areas obtained by equally dividing the object to be scanned around the rotation center point of the rotating stage is set as a scanning area, and the input / output axis of the equipment scans this scanning area, and a second drive unit that drives the rotating stage so that the unscanned area is positioned in the scanning area.

[0007] Furthermore, the scanning stage of the present invention is characterized by comprising an XY stage, an instrument mounted on the XY stage, a rotating stage fixed to a coordinate system common to the XY stage and holding and rotating an object to be scanned, a first drive unit that drives the XY stage so that one of a plurality of areas obtained by equally dividing the object to be scanned around the rotation center point of the rotating stage is set as a scanning area, and the input / output axis of the instrument scans this scanning area, and a second drive unit that drives the rotating stage so that the unscanned area is positioned in the scanning area. [Effects of the Invention]

[0008] The present invention provides a compact scanning stage that allows the instrument to perform surface scanning on objects having large diameters. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing the appearance of a scanning stage according to a first embodiment of the present invention. [Figure 2] 4A, 4B, 4C, and 4D are perspective top views of a scanning stage for explaining the operation of the XY stage in the first embodiment. [Figure 3] (A) (B) (C) (D) Top view explaining the operation of the rotation stage in the scanning stage. [Figure 4] FIG. 10 is a perspective view showing the appearance of a scanning stage according to a second embodiment of the present invention. [Figure 5]10A, 10B, 10C, and 10D are perspective top views of a scanning stage for explaining the operation of an XY stage in the second embodiment. [Figure 6] 1A is a diagram illustrating the effect of a scanning region showing an embodiment of a scanning stage of the present invention, and FIG. 1B is a diagram illustrating a scanning region showing a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0010] (First embodiment) A first embodiment of the present invention will be described below with reference to the accompanying drawings. Fig. 1 is a perspective view showing the appearance of a scanning stage 10A (10) according to the first embodiment. As described above, the scanning stage 10A (10) includes an XY stage 21, a device 17 fixed to a coordinate system (XYZ) common to the XY stage 21, and a rotating stage 22 that is mounted on the XY stage 21 and that holds and rotates a scanning target 15.

[0011] Furthermore, the scanning stage 10 is equipped with a first drive unit 11 that drives the XY stage 21 so that the input / output axis 18 of the device 17 scans a scanning area R, one of which is set as a scanning area R by equally dividing the object to be scanned 15 into multiple areas (A, B, C, D) relative to the rotation center point O of the rotating stage 22, and a second drive unit 12 that drives the rotating stage 22 so that the unscanned area (A, B, C, D) is positioned in the scanning area R.

[0012] In the embodiment, the scanning object 15 is exemplified as a wafer for semiconductor manufacturing, but is not limited to this and may also include a liquid crystal substrate, an electronic circuit board, and other panels or sheets on which patterns are formed. The shape is also not limited to a circle and may include a rectangle.

[0013] The XY stage 21 is composed of a base body 25 that defines the XYZ coordinate system, an X-axis rail 26 that is provided on the base body 25 along the X-axis of this coordinate system, an X-axis table 27 that moves along the X-axis rail 26, a Y-axis rail 28 that is provided on the X-axis table 27 along the Y-axis of this coordinate system, and a Y-axis table 29 that moves along the Y-axis rail 28.

[0014] This allows the XY stage 21 to arbitrarily horizontally displace the Y-axis table 29 in the XY plane coordinate system. Although not shown, the linear displacement of each of the X-axis table 27 and the Y-axis table 29 can be achieved by converting the rotational angular displacement of a rotary motor using a mechanical element such as a ball screw, or by a linear motor.

[0015] The device 17 is mechanically and structurally integrated with the base body 25 of the XY stage 21, and is fixed to the XYZ coordinate system together with the XY stage 21. In this embodiment, the device 17 is exemplified as an optical camera that observes the surface of the scanning object 15. This optical camera observes the pattern on the scanning object 15 (wafer) from a direction along the input / output axis 18. Note that the observation light source (not shown) may irradiate light in a direction along the input / output axis 18, or may irradiate light from an oblique direction relative to the input / output axis 18.

[0016] An optical sensor detects the light reflected from the surface of the scanned object 15 along the input / output axis 18. Light sources for observation include visible light, ultraviolet light, deep ultraviolet light, vacuum ultraviolet light, X-rays, and electron beams. Device 17 is not limited to optical cameras for surface observation, but also includes electrical inspection testers, electron guns, ion guns, foreign material detectors, exposure machines, and other inspection and pattern projection devices. When device 17 is a transfer system using an exposure machine, the part of device 17 that corresponds to the reticle (precise light-dark pattern) is fixed to the coordinate system (XYZ).

[0017] The rotary stage 22 is composed of a rotary motor 23 whose housing is fixed to the upper surface of the Y-axis table 29 of the XY stage 21, and a rotary table 24 that is supported by the rotation shaft of the rotary motor 23 and holds the scanning object 15 on its upper surface. This allows the rotary stage 22 to rotate and displace the rotary table 24 in a θ rotation coordinate system defined by the Y-axis table 29.

[0018] The scanning object 15 is divided into a plurality of equal areas (A, B, C, D) symmetrically about its rotation center point O. One of the areas is set as the scanning area R, and the input / output axis 18 of the device 17 is scanned. Note that in the embodiment, the scanning object 15 is shown as being divided into four equal areas (A, B, C, D), but is not limited to this, and may be divided into two or more equal areas.

[0019] 2(A), (B), (C), and (D) are top perspective views of the scanning stage 10, illustrating the operation of the XY stage 21. The first driving unit 11 (FIG. 1) drives the Y-axis table 29 of the XY stage 21 so that the input / output shaft 18 of the device 17 scans the scanning region R. Note that while the XY stage 21 is operating, the rotating stage 22 is in a stopped state.

[0020] 3(A), (B), (C), and (D) are top views illustrating the operation of the rotating stage 22 in the scanning stage 10. The second driving unit 12 (FIG. 1) drives the rotating stage 22 so that the unscanned areas (A, B, C, and D) of the scanning object 15 are positioned in the scanning area R. Note that while the rotating stage 22 is operating, the XY stage 21 (FIG. 2) is stationary.

[0021] (Second embodiment) A second embodiment of the present invention will now be described with reference to the accompanying drawings. Fig. 4 is a perspective view showing the appearance of a scanning stage 10B (10) according to the second embodiment. Figs. 5(A), (B), (C), and (D) are top perspective views of the scanning stage 10B illustrating the operation of the XY stage 21 in the second embodiment.

[0022] Thus, the scanning stage 10B (10) comprises an XY stage 21, equipment 17 provided on the XY stage 21, and a rotating stage 22 that is fixed to a coordinate system (XYZ) common to the XY stage 21 and that holds and rotates the scanning object 15. Note that in Fig. 4, the scanning object 15 and areas (A, B, C, D) cannot be seen from the angle shown in the figure, but are shown as seen through from the back of the rotating stage 22.

[0023] Furthermore, the scanning stage 10 is equipped with a first drive unit 11 that drives the XY stage 21 so that the input / output axis 18 of the device 17 scans a scanning area R, one of which is set as a scanning area R by equally dividing the object to be scanned 15 into multiple areas (A, B, C, D) relative to the rotation center point O of the rotating stage 22, and a second drive unit 12 that drives the rotating stage 22 so that the unscanned area (A, B, C, D) is positioned in the scanning area R.

[0024] In the second embodiment, the device 17 is fixed to the upper surface of the Y-axis table 29 of the XY stage 21. Also in the second embodiment, the housing of the rotating stage 22 is mechanically integrated with the base body 25 of the XY stage 21, and thus the rotating stage 22 is fixed to the XYZ coordinate system together with the XY stage 21. The rotating table 24, which is rotatably supported by the housing of the rotating stage 22, holds the scanning object 15 on its upper surface. This allows the rotating stage 22 to rotate and displace the rotating table 24 in the θ rotating coordinate system defined by the XYZ coordinate system.

[0025] The explanation of the first embodiment based on FIG. 3 is also applicable to the explanation of the second embodiment.

[0026] FIG. 6(A) is an explanatory diagram of the effect of the scanning region R showing an embodiment of the scanning stage 10 of the present invention. FIG. 6(B) is an explanatory diagram of the scanning region R' showing a comparative example. In this way, in the scanning stage 10, by rotating the rotary stage 22, one of a plurality of regions (four shown) into which the scanning object 15 is equally divided is positioned in the fixed scanning region R. This has the effect of making it possible to provide a compact scanning stage 10 that can scan the surface of the scanning object 15, such as a substrate with a large diameter, with the input / output shaft 18 of the device 17. [Explanation of symbols]

[0027] 10...scanning stage, 11...first drive unit, 12...second drive unit, 15...scanning object, 17...equipment, 18...input / output axis, 21...XY stage, 22...rotating stage, 23...rotating motor, 24...rotating table, 25...base body, 26...X-axis rail, 27...X-axis table, 28...Y-axis rail, 29...Y-axis table, R...scanning area.

Claims

1. An XY stage; a device fixed to a coordinate system common to the XY stage; a rotation stage provided on the XY stage for holding and rotating a scanning object; one of a plurality of areas obtained by equally dividing the scanning object with respect to the rotation center point of the rotation stage is set as a scanning area; a first drive unit that drives the XY stage so that the input / output axis of the device scans the scanning area; a second driving unit that drives the rotary stage so that the unscanned region is positioned in the scanning region.

2. An XY stage; An apparatus provided on the XY stage; a rotary stage that is fixed to a coordinate system common to the XY stage and that holds and rotates a scanning object; one of a plurality of areas obtained by equally dividing the scanning object with respect to the rotation center point of the rotation stage is set as a scanning area; a first drive unit that drives the XY stage so that the input / output axis of the device scans the scanning area; a second driving unit that drives the rotary stage so that the unscanned region is positioned in the scanning region.

3. 3. The scanning stage according to claim 1, The scanning stage, wherein the object to be scanned is a wafer for semiconductor manufacturing.

4. 3. The scanning stage according to claim 1, The instrument is a scanning stage that is an optical camera that observes the surface of the scanned object.

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