JP2005156481A - Sample-positioning apparatus and sample-measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sample-positioning apparatus for compactly integrating a mechanism for receiving/transferring a sample irradiated with an ion beam or an electron beam, and a mechanism for positioning in a vacuum chamber having severe spatial constraints. <P>SOLUTION: The plate sample 21 is carried into the vacuum chamber 11, received within the vacuum chamber, and positioned at a predetermined position within the vacuum chamber. The positioned sample 21 is irradiated with the ion beam or the electron beam. A ϕ-axis motor 34 is provided, receives the sample 21 at a position opposite to a side for introducing the beam into the vacuum chamber 11, makes the received sample 21 flip and orients the received sample 21 to the beam. The sample 21 is positioned so as to be aligned with the axis line of the beam. An axis line matching means comprises a ω-axis motor 28 and a Y-axis motor 32 and is rotated about the ω-axis, and is moved horizontally along Y-axis. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a sample positioning device used in an analyzer or an irradiation device for analyzing or processing a sample by irradiating the sample with an ion beam or an electron beam, and particularly for handling such as sample loading, analysis such as beam irradiation, and carrying out. The present invention relates to a sample positioning device having a suitable structure.

  Rutherford backscattering analyzers and the like are examples of analyzers or irradiation devices that analyze or process a sample by irradiating the sample with an ion beam or an electron beam.

  In general, in an apparatus that irradiates a sample with an ion beam or an electron beam in a vacuum vessel such as the Rutherford backscattering analyzer, it is necessary to irradiate a predetermined position on the sample with respect to the axis of the beam. The sample must be positioned at an arbitrary position on the vertical plane, and the beam axis should match the sample position. Further, since it is necessary to position the sample at the focal point of the beam, it is necessary to position the sample at an arbitrary position along the axis of the beam and to irradiate the sample with an ion beam or an electron beam at the focal point of the beam. Furthermore, in order to analyze and process the sample, it is necessary to incline the sample with respect to the axis of the beam in order to adjust the crystal structure of the sample and the irradiation direction of the beam. Thus, the sample positioning device needs to have many degrees of freedom such as rotational movement and horizontal movement.

  Naturally, since the sample is carried in from the outside of the vacuum container, a vacuum is used to receive the loaded sample inside the vacuum container or to carry the sample after analysis or processing out of the vacuum container. It must be delivered to the sample unloading device inside the container, and the structure must be convenient for this receipt and delivery.

  Furthermore, since it is preferable to make the vacuum vessel as small as possible from the viewpoint of evacuation, there is almost no wasted space in the vacuum vessel, and it is necessary to compact the above-described many positioning mechanisms and receiving mechanisms.

  With reference to FIG. 5, it will be explained that the space restriction inside the vacuum vessel is severe for an apparatus for analyzing or processing a sample by irradiating the sample with an ion beam or an electron beam. In FIG. 5, reference numeral 11 denotes a vacuum vessel. In this vacuum vessel 11, an ion beam or an electron beam is irradiated from above. A sample 12 to be analyzed or processed is carried into and out of the vacuum vessel 11 by a transfer rod 14 connected via a vacuum valve 13. In FIG. 5, since the beam is irradiated from above, of course, nothing can be arranged in the upper portion P from the place where the sample 12 should be located. Moreover, since the electromagnet is normally arrange | positioned at the both sides M of a vacuum vessel, nothing can be arrange | positioned also in this direction. Furthermore, it is necessary to attach a magnetic lid to the bottom N of the vacuum vessel so as not to disturb the magnetic field in the vacuum vessel 11, and nothing can be arranged in this direction. From the above, as a positioning device used in such an analyzer or irradiation device, the sample is delivered at the bottom on the opposite side to the side where the beam of the vacuum vessel is introduced, and the received sample is vacuumed. It is necessary to carry it to the analysis position in the container and to position it accurately at the analysis position. However, as described with reference to FIG. 5 above, the space for sample transfer is very limited, and it is necessary to employ a very high level transfer and positioning mechanism.

As an example of such a positioning mechanism, there is a technique described in Patent Document 1. The technique described in Patent Document 1 supports at least an R-θ stage 9 that linearly moves in a horizontal direction and rotationally moves around a vertical axis, and supports the R-θ stage 9 and also an analysis position. Is provided with a rotationally moving stage that rotates so as to be positioned at two angular positions of 90 degrees around a vertical axis passing through.
JP 2002-131250 A

  However, the structure described in Patent Document 1 is based on the premise that the sample is delivered on the beam irradiation space side of the positioning device. As described above, in Patent Document 1, since the sample is transferred at the upper portion of the sample positioning device, the sample is transferred at a location at least as high as the positioning device from the bottom of the vacuum vessel. become. However, since the sample is transported to the vacuum chamber through the transport path connected to the bottom of the apparatus, the width of the sample transport path needs to be formed to be the vertical width corresponding to the height of the sample positioning device. As a result, the problem that the volume of the vacuum vessel becomes large was incorporated. In this case, as a matter of course, the size of the vacuum vessel is increased accordingly, which not only increases the cost of the vacuum vessel, but also increases the time required for evacuation.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a mechanism and a beam for delivering a sample to be irradiated with an ion beam or an electron beam in a vacuum container having severe space restrictions. It is an object of the present invention to provide a sample positioning device capable of reducing the volume of the vacuum vessel substantially in a compact manner with respect to a mechanism for positioning with respect to the vacuum vessel.

In order to achieve the above object, the present invention is to receive a sample carried into a vacuum vessel and transport it to the vicinity of a measurement location inside the vacuum vessel and to appropriately position and position the sample. In the sample positioning device,
After the sample is received from the sample loading device at the bottom of the vacuum vessel, the sample is reversed and the sample is transported to the vicinity of the measurement location, and at least the position of the sample is adjusted after the transport operation. It is configured as a sample positioning device. Thereby, the sample carrying-in passage can be narrowed, and the volume of the entire vacuum vessel can be reduced. In addition, a mechanism that can receive a sample at a position suitable for loading and unloading the sample in a vacuum container with severe space restrictions and position it at a predetermined position in the vacuum container can be compactly assembled.

  In addition, as a mechanism for adjusting the direction of the sample, it is desirable to have a tilting unit that tilts the sample with respect to the axis of the ion beam or electron beam in order to analyze the crystal structure of the sample. Thereby, analysis of the crystal structure of the sample can be easily performed.

  The tilting means is composed of at least two-axis rotating mechanisms, and each rotating mechanism is attached to at least two rings arranged coaxially, and the rotating mechanism attached to the outer ring tilts the inner ring. It is more desirable if it is. By constituting in this way, this tilting means can be put together compactly.

  If the mechanism that inverts the sample can be shared with the mechanism that tilts the inner ring, the overlapping mechanism can be shared and one axis can be omitted, so that the entire apparatus can be integrated more compactly. .

  Further, as a mechanism for adjusting the position of the sample, there is an axis matching means for matching the sample with the axis of the ion beam or electron beam, and the axis matching means is reversed while being placed on the tilting means. It is desirable to be driven as follows. This simplifies the positioning of the sample with respect to the axis of the beam, and allows the sample to be analyzed or processed efficiently. Moreover, the whole can be summarized in an extremely compact manner.

  Preferably, the axis line matching means comprises at least one slide mechanism and at least one rotation mechanism. By combining the slide mechanism and the rotation mechanism in this way, the means for matching the axis becomes compact, and interference with other obstacles can be suppressed when the tilting means is reversed.

  Further, as a mechanism for adjusting the position of the sample, it further comprises focusing means for moving the sample along the axis of the ion beam or electron beam, and the focusing means includes the axis matching means and the tilting means. It is desirable to move them integrally. As a result, focusing can be easily performed, and the whole can be made compact.

As a sample measuring apparatus using the sample positioning apparatus as described above, a sample carried into the vacuum vessel is received and transported to the vicinity of the measurement location inside the vacuum vessel, and the position and direction of the sample are determined. In a sample measuring device equipped with a sample positioning device for positioning appropriately,
After receiving the sample from the sample carry-in device at the bottom of the vacuum vessel, the sample is reversed, and the sample is transported to the vicinity of the measurement location, and at least the position of the sample is adjusted after the transport operation. There is provided a sample measuring apparatus characterized by the above.

  As described above, according to the present invention, the entire vacuum container can be compactly collected. In addition, a mechanism for receiving and delivering a sample irradiated with an ion beam or an electron beam and a mechanism for positioning the sample with respect to the ion beam or the electron beam can be compactly integrated. Therefore, it is possible to reduce the size of an expensive vacuum vessel, contribute to the overall cost reduction, reduce the time required for evacuation, and perform sample analysis or sample processing efficiently. it can.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In addition, the following embodiment is an example which actualized this invention, Comprising: It is not the thing of the character which limits the technical scope of this invention.

  1 is a front sectional view of the positioning device according to the embodiment of the present invention, FIG. 2 is a side sectional view of the positioning device according to the embodiment of the present invention, and FIG. FIG. 4 is a side sectional view showing a state in which the positioning device according to the embodiment is inverted for sample reception, and FIG. 4 is an operation explanation continuous view for explaining the operation of the positioning device according to the embodiment of the present invention. 1 is a cross-sectional view taken along the line BB in FIG. 2, FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line CC in FIG. For the sake of explanation, some parts are simplified or the cutting position is shifted.

  First, an embodiment of the present invention will be described with reference to FIGS. This embodiment is an example in which the sample positioning device of the present invention is used in a Rutherford backscattering analyzer (RBS analyzer). Needless to say, the RBS analyzer is merely an example of an analyzer that can use the sample analyzer of the present invention. The sample analyzer of the present invention can also be used in an analyzer or an irradiation apparatus that performs analysis or processing by irradiating a sample with another ion beam or electron beam.

  The sample positioning device shown in FIGS. 1 and 2 is disposed in a vacuum vessel (not shown). In the figure, reference numeral 21 denotes a disk-shaped sample (for example, a 6-inch or 8-inch wafer) irradiated with an ion beam, and this sample 21 is gripped by the four gripping claws 22 from the four sides. Each of the four gripping claws 22 is supported by a rod 23 that advances and retreats in the radial direction of the sample so as to be able to advance and retract in the radial direction (sample center direction) from the sample center. Is elastically biased in the direction of gripping. Further, a holding roller 25 is brought into contact with the rear surface of the sample 21, and the sample 21 is gripped in cooperation with the gripping claws 22. By these mechanisms, the sample 21 is received from the transfer rod 14 (FIG. 5) to the sample positioning device inside the vacuum vessel, and is transferred from the sample positioning device to the transfer rod.

  Note that the number of the gripping claws 22 is not limited to four, and may be three or five. In addition, it may be due to suction fixation rather than fixation with gripping claws.

  These sample receiving / delivery mechanisms are arranged on the rotary table 26. The rotary table 26 is supported by a bearing 27, and can be rotated 360 degrees around the ω axis (FIG. 2) by a ω axis motor 28 disposed on the axis of the rotary table 26. A bearing 27 supporting the rotary table 26 is placed on a slide table 29. The slide table 29 is a ball screw 31 via an L-shaped member 30 protruding from the lower surface of the slide table 29. It is connected to the. The slide table 29 can be horizontally moved in a range of about 6 cm to 8 cm in the Y axis direction by a Y axis motor 32 connected to the ball screw 31. In the case of the present embodiment, as shown in FIG. 1, since the ball screw 31 is arranged at a position shifted from the center line of the slide table 29 (deviation amount δ), the ball screw 31 is symmetric with respect to the center line. A linear guide 33 is arranged at a certain position, and the slide table 29 is guided in the Y-axis direction by the linear guide 33 and the ball screw 31. In the case of the present embodiment, these mechanisms allow the sample 21 to be accurately positioned at an arbitrary position on a plane perpendicular to the axis of the ion beam. Can match the axis. That is, the axis line matching means is constituted by these mechanisms.

  In this embodiment, the axis coincidence means is constituted by the rotation around the ω axis and the horizontal movement in the Y axis direction. However, positioning at an arbitrary position on a plane perpendicular to the axis of the ion beam is possible. As long as it is possible, both the two axes may be rotated, or both the two axes may be moved horizontally. Furthermore, a third axis may be added.

  The mechanism that constitutes these axis matching means is rotatably attached to the inner ring 36 by two opposing φ-axis mounting portions 35, and is entirely within a range of about plus or minus 10 degrees by the φ-axis motor 34. It can be tilted and can be inverted 180 degrees as shown in FIG. That is, as shown in FIG. 3, the sample 21 is received while being rotated to a position opposite to the side where the ion beam is introduced, and the received sample 21 is inverted integrally with the axis line matching means so as to be ion beam. It can be opposed to. In the present embodiment, the sample is reversed between the receiving position and the beam irradiation position by these mechanisms.

  Next, the inner ring 36 is arranged inside an outer ring 39 arranged coaxially with the inner ring 36. A θ-axis motor 37 is attached to the outer ring 39, and the θ-axis motor 37 tilts the inner ring 36 within a range of about plus or minus 10 degrees by two opposing θ-axis mounting portions 38. Can be adjusted. The inner ring 36 and the outer ring 39 are provided with a plurality of cutout portions 40 to prevent interference with the motor 34 during the reversing operation and the tilting operation described above. In the present embodiment, the outer ring 39, the inner ring 36, the θ-axis motor 37, the φ-axis motor 34, and the like constitute the tilting means.

  In this embodiment, the φ-axis motor 34 is shared by the mechanism for inverting the sample and the mechanism for tilting the inner ring, but these may be provided separately. Further, a third axis may be provided as a tilting means to form a triple structure, or conversely, one axis may be omitted.

  In the present embodiment, the θ-axis motor 37 and the φ-axis motor 34 are intersected at an angle of about 135 degrees in consideration of reversal interference. However, these axes may be orthogonal. , The crossing angle may be further increased.

  Furthermore, in the case of this embodiment, it is inverted 180 degrees, but when the ion beam is introduced from the side, it may be opposed to the ion beam by reversing it 90 degrees.

  Next, the focusing means and its operation according to the embodiment of the present invention will be described with reference to FIG. In FIG. 4, reference numeral 51 denotes a vacuum vessel, and a sample 52 is carried into the vacuum vessel 51 by a transfer rod 53. In FIG. 4, reference numeral 54 denotes a shaft, and three shafts are erected in the vertical direction of the vacuum vessel 51, and the mechanism shown in FIGS. 1 and 2 is connected to each shaft 54 via a linear bush 55. ing. A Z-axis motor (not shown) is connected above one of the shafts 54, and a ball screw (not shown) is rotationally driven by the Z-axis motor, so that it can move up and down about 30 to 50 cm in the Z-axis direction. Has been. Thereby, the sample can be focused along the axis of the ion beam. In the case of this embodiment, the focusing means is constituted by these mechanisms.

  In the case of the present embodiment, the focusing means moves in the vertical direction inside the vacuum vessel, but in the case of a horizontal analyzer, it moves in the horizontal direction.

  Next, the operation of this embodiment will be described. As shown in FIG. 4A, the sample 52 is first carried into the inside of the vacuum vessel 51 by the transfer rod 53 and positioned below the positioning mechanism according to the present embodiment. In this state, the gripping claw 22 is closed and the sample 52 is gripped from four directions, and the holding roller 25 comes into contact with the sample 52, and the sample 52 is securely gripped by the gripping claw 22 and the holding roller 25. Thereafter, as shown in FIG. 4B, the transfer rod 53 is retracted and the positioning mechanism is moved upward by the focusing means 54 and 55. In this state, as shown in FIG. 4C, it is inverted 180 degrees to face the ion beam. The positions of the ion beam and the sample axis are adjusted with respect to the beam by the axis matching means, and a predetermined analysis is performed over the entire surface of the sample as a wafer. At this time, the sample is tilted as necessary by the tilting means to adjust the direction with respect to the beam. After the predetermined analysis is completed, the sample 52 is carried out of the vacuum vessel 51 in the reverse flow as described above.

    In the above embodiment, the sample is accurately tilted (direction) and positioned after the sample has reached the vicinity of the measurement location. However, the sample tilt is measured before or during conveyance to the measurement location. It is also possible to adjust with. Such pre-adjustment can reduce the time required for processing.

The front sectional view of the positioning device concerning the embodiment of the present invention. The side sectional view of the positioning device concerning the embodiment of the present invention. The side sectional view showing the state where the positioning device concerning the embodiment of the present invention was reversed for sample receipt. Operation | movement description continuous figure explaining operation | movement of the positioning device which concerns on embodiment of this invention. Explanatory drawing explaining the space restrictions in a vacuum vessel.

Explanation of symbols

11 Vacuum container 21 Sample 26 Rotary table (Axis matching means)
28 ω-axis motor (axis matching means)
29 Slide table (Axis matching means)
32 Y-axis motor (Axis matching means)
34 φ axis motor (reversing means, tilting means)
36 Inner ring (tilting means)
37 θ-axis motor (tilting means)
39 Outer ring (focusing means)
54 Shaft (focusing means)
55 Linear bushing (focusing means)

Claims (8)

In a sample positioning apparatus for receiving a sample carried into a vacuum vessel and transporting it to the vicinity of a measurement location inside the vacuum vessel, and appropriately positioning the position and direction of the sample,
After the sample is received from the sample carry-in device at the bottom of the vacuum vessel, the sample positioning device is reversed and the sample is transported to the vicinity of the measurement location, and at least the sample position is adjusted after the transport operation. Sample positioning device.   2. The sample positioning apparatus according to claim 1, further comprising: tilting means for tilting the sample with respect to an axis of the ion beam or electron beam in order to analyze a crystal structure of the sample as a mechanism for adjusting the direction of the sample.   The tilting means comprises at least two-axis rotating mechanisms, each rotating mechanism is attached to at least two rings arranged coaxially, and the rotating mechanism attached to the outer ring tilts the inner ring. The sample positioning device according to claim 2.   The sample positioning device according to claim 3, wherein a mechanism for inverting the sample is shared with a mechanism for tilting the inner ring.   As a mechanism for adjusting the position of the sample, it has axis matching means for matching the sample with the axis of the ion beam or electron beam, and the axis matching means is reversed while being placed on the tilting means. The sample positioning device according to any one of claims 2 to 4, which is driven.   6. The sample positioning device according to claim 5, wherein the axis line matching means comprises at least one slide mechanism and at least one rotation mechanism.   The mechanism for adjusting the position of the sample further includes a focusing means for moving the sample along the axis of the ion beam or the electron beam, and the focusing means integrates the axis matching means and the tilting means. The sample positioning device according to claim 5 or 6, wherein the sample positioning device is moved in a moving manner. In a sample measuring apparatus comprising a sample positioning device for receiving a sample carried into the vacuum vessel and transporting it to the vicinity of a measurement location inside the vacuum vessel and appropriately positioning the position and direction of the sample,
After receiving the sample from the sample carry-in device at the bottom of the vacuum vessel, the sample is reversed and the sample is transported to the vicinity of the measurement location, and at least the position of the sample is adjusted after the transport operation. A sample measuring apparatus comprising:

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