JP4550540B2 - Sample stage and ion sputtering equipment - Google Patents

Description

  The present invention relates to a sample stage for holding a sample rotatably, and more particularly to a sample stage suitable for use in an ion sputtering apparatus.

  As shown in FIG. 4, in the ion sputtering apparatus, a sample stage having a rotatable table 1 for holding the sample 6 is disposed in the vacuum chamber 20, and an ion source 21 is disposed immediately above the sample 6. . In the case of the sample 6 having a large surface unevenness, the irradiation angle of the ion particle beam 22 with respect to the surface of the sample is not constant. As shown in FIG. 5, the thickness of the film 23 on the surface of the sample 6 is not uniform. Therefore, a tiltable sample stage has been proposed.

  In the sputtering apparatus described in Japanese Patent Application Laid-Open No. 10-121237, a substrate holder on which a substrate to be processed is placed is tiltable and rotatable. However, in this example, the tilt angle must be set for each measurement. In the vapor deposition apparatus described in Japanese Patent Application Laid-Open No. 5-228801, a swing mechanism is provided that supports and rotates a vapor deposition source inclined at a predetermined angle with respect to a vapor deposition film forming surface of a vapor deposition member. However, even in this example, the tilt angle must be set for each measurement. In the film forming apparatus described in Japanese Patent Laid-Open No. 6-57423, there is provided a mechanism for rotating the holder inner surface by tilting the inner surface of the holder by a predetermined angle with respect to the horizontal line. In this example, the tilt angle cannot be tilted.

Japanese Patent Laid-Open No. 10-121237 Japanese Patent Laid-Open No. 5-228801 JP-A-6-57423

  In the conventional apparatus, the sample stage is tilted, but the tilt angle is constant. Therefore, it is impossible to form a uniform film on the surface of complicated irregularities. For example, the projection can be easily sputtered, but the sputtered particles do not reach the back of the recess.

  An object of the present invention is to provide means capable of freely changing the angle of the surface of a sample with a simple apparatus.

  The sample stage includes a table for holding a sample, a support device for rotatably supporting the table, a cam engaged with the table, and a rotation driving device for rotating the cam. As the table rotates, the table rotates around the central axis and simultaneously tilts with respect to the horizontal plane.

  According to the present invention, it is possible to realize sputter coating with a uniform film thickness even for a sample with unevenness.

  Embodiments of the present invention will be described below with reference to the drawings. 1A is a top view of a sample stage according to the present invention, FIG. 1B is a front view, and FIG. 1C is a right side view. The sample stage of this example includes a table 1, a vertical shaft 2, a spherical bearing 7, a cam 3, a cam shaft 4, and a rotation drive device 5. A plurality of samples 6 are placed on the upper surface 1A of the table 1 by a method such as adhesion. As shown in FIG. 1B, the table 1 is rotatably held by a spherical bearing 7 provided at the upper end of the vertical shaft 2. The cam 3 is engaged with the outer peripheral portion of the lower surface 1B of the table 1. That is, the cam mechanism is constituted by the cam 3 and the lower surface 1B of the table 1. The cam 3 and the lower surface 1B of the table 1 may be engaged by frictional contact, but may be engaged by a gear mechanism comprising a rack provided on the lower surface 1B of the table 1 and a pinion of the cam 3.

  The cam 3 is mounted on a cam shaft 4, and the cam shaft 4 is connected to a rotation drive device 5. The rotation drive device 5 may be anything as long as it rotates the cam shaft 4, and may be, for example, a motor and a gear mechanism, a motor and a friction transmission mechanism, or the like.

  When the cam shaft 4 is rotated by the rotation driving device 5 and the cam 3 is rotated, the table 1 is perpendicular to the table 1 by the spherical bearing 7 and the center of the table by the cam mechanism including the cam 3 and the lower surface 1B of the table 1. Rotate around the axis of rotation through and tilt at the same time. That is, the rotation axis of the table is inclined with respect to the vertical axis, and the table 1 is inclined with respect to the horizontal plane.

  Below, the case where the outer periphery of the cam 3 is an ellipse is demonstrated. When the major axis of the ellipse is 2a and the minor axis is 2b, the length of the outer periphery of the ellipse is π (a + b).

  Let x be the point that engages with the cam 3 on the lower surface 1B of the table 1. Let R be the distance from the rotation axis of the table 1 to the engagement point x. When the table 1 rotates once, the engagement point x draws a circle with a radius R, and its locus becomes 2πR.

  In this example, the ratio 2πR / π (a + b) of the locus 2πR of the engagement point x and the outer circumferential circle π (a + b) of the ellipse is selected to an appropriate value. Here, for example, it is assumed that the table is rotated only once in one sputtering process. When 2πR / π (a + b) = 2/1, the cam 3 rotates twice while the table 1 rotates once. When 2πR / π (a + b) = n / 1, the cam 3 rotates n times while the table 1 rotates once.

  n may be a natural number or a number other than a natural number. When n is a natural number, when the table 1 rotates once, the cam 3 returns to the initial rotation angle, that is, the initial phase. However, when the number is other than the natural number, the cam 3 does not return to the initial phase even if the table 1 rotates once.

  For example, when n = 1 / 0.49≈2.04, the cam 3 rotates 2.04 while the table 1 rotates once. That is, when the cam 3 makes two revolutions, the table 1 has not yet made one revolution.

  For example, when n = 1 / 0.51≈1.96, the cam 3 rotates 1.96 while the table 1 rotates once. That is, when the cam 3 rotates twice, the table 1 exceeds one rotation.

  In order to form a uniform film thickness on an uneven sample by sputtering, n should not be a natural number.

  The relationship between the rotation angle and the tilt angle of the table 1 will be described with reference to FIG. The rotation axis of the table 1, that is, the spherical bearing 7 is set as the origin O, the horizontal axis is the x axis, the vertical direction is the y axis, and the tilt angle is measured counterclockwise from the positive direction of the x axis. 2 (a) and 2 (b) show a state in which the major axis of the ellipse of the cam 3 is engaged with the lower surface 1B of the table 1, and the inclination angle of the table 1 is the maximum. 2 (c) and 2 (d) show a state where the minor axis of the ellipse of the cam 3 is engaged with the lower surface 1B of the table 1, and the inclination angle of the table 1 is the smallest.

  While the cam 3 makes one revolution, the tilt angle of the table 1 changes from maximum to zero, changes from zero to minimum, and then returns to zero. That is, there are two positions where the tilt angle of the table 1 becomes zero as shown in FIG.

  Another example of the sample stage according to the present invention will be described with reference to FIG. In this example, a pressing means 10 for pressing the table 1 from the top to the bottom is provided on the upper side of the table 1 and at the position where the cam 3 is disposed. The presser means 10 includes a presser member 11 at the lower end and a spring 12 that presses the presser member 11 downward. The tip of the pressing member 11 may be provided with a rotatable roll. Thus, by pressing the table 1 from the top to the bottom by the pressing means 10, the engagement between the lower surface 1B of the table 1 and the cam 3 is ensured. That is, the lower surface 1B of the table 1 and the cam 3 are prevented from separating.

  Although the case where the outer periphery of the cam 3 is an ellipse has been described here, it is needless to say that the shape may be other than an ellipse.

  The sample stage of this example can be applied to an ion sputtering apparatus, but can be applied to other thin film forming apparatuses, microfabrication apparatuses, and the like.

  The example of the present invention has been described above, but the present invention is not limited to the above-described example, and various modifications can be made by those skilled in the art within the scope of the invention described in the claims. It will be understood.

It is a figure which shows the example of the sample stand by this invention. It is a figure which shows the relationship between the inclination angle of the table of the sample stand by this invention, and the rotation angle of a cam. It is a figure which shows the other example of the sample stand by this invention. It is a figure which shows the outline of an ion sputtering device. It is a figure for demonstrating the structure of the film of the sample surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Table, 2 ... Vertical axis | shaft, 3 ... Cam, 4 ... Cam shaft, 5 ... Rotation drive device, 6 ... Sample, 10 ... Pressing means, 11 ... Pressing member, 12 ... Spring

Claims (4)

  A table that holds the sample; a support device that rotatably supports the table; a cam that is engaged with the table; and a rotation drive device that rotates the cam; and when the cam rotates, A sample stage used in an ion sputtering apparatus, wherein the table is configured to rotate about a central axis and simultaneously tilt with respect to a horizontal plane. 2. The sample stage used in the ion sputtering apparatus according to claim 1, wherein the n is not a natural number when the cam rotates n times while the table rotates once. Sample stage. 2. The sample stage used in the ion sputtering apparatus according to claim 1, further comprising presser means for pressing the table against the cam.   An ion comprising: the sample stage according to any one of claims 1 to 4, a vacuum chamber that accommodates the sample stage, a target of a material to be sputtered on the sample surface, and a power source that applies a voltage to the target. Sputtering device.

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