JPS5948509B2 - Sample tilting device such as electron microscope - Google Patents

Description

[Detailed description of the invention] The present invention relates to a sample tilting device for an electron microscope or the like.

Generally, in an electron microscope in which a sample tilting mechanism is attached to a sample plane moving mechanism, when the sample is tilted, a height shift or a lateral change on the sample surface, that is, a change in position with respect to the optical axis occurs.

The former appears as a change in focus, magnification, and electron diffraction camera length, and the latter appears as a shift in the field of view, which poses a major operational obstacle.

For this reason, a so-called eucentric goniometer has conventionally been used as a sample tilting device that does not shift the field of view even when the sample is tilted, and does not shift the focus even when the sample is moved.

As shown in Fig. 1, this eucentric goniometer first aligns the tilt axis 1 with the optical axis by operating the tilt axis moving screw 9, and then aligns the sample surface with the tilt axis 1 to move in the height direction. This is a mechanism in which the sample is moved within an inclined surface after adjustment.

However, the control mechanism in the X direction in the conventional necentric goniometer involves interposing a floating body composed of the X control shaft 2 and the connecting rod 3 between the lever body 19 and the sample holding rod 4. The tip of the connecting rod 3 is brought into contact with the tip of the lever body 19, and the control shaft 2 and the connecting rod 3 are driven by rotating the X control screw 6 to move the sample on the X axis. In the conventional structure where the distance between As a result, the field of view changes, and especially when taking photographs, it is difficult to obtain high-resolution photographs because a moving object must be photographed.

The present invention has been made in view of the above points, and its purpose is to minimize the effects of thermal expansion and contraction of the above-mentioned members due to temperature changes in the outside air and thermal effects from nearby heating elements. The objective is to obtain extremely high resolution electron micrographs by reducing the drift of the sample and keeping the sample stationary at all times.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A sample tilting device for an electron microscope or the like according to the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 2, the sample tilting device of the electron microscope includes a movement control mechanism in the Y direction and Z direction (optical axis direction) provided on the right side of the electron microscope main body 7, and a movement control mechanism provided on the lower side of the electron microscope main body 7 in the figure. The sample 21 placed on the tip of the sample holding rod 4 is moved by the operation of these control mechanisms.
is set at an appropriate inclination and an appropriate height on the optical axis.

First, the movement control mechanism in the Y direction will be explained. In FIG. 2, an inclined base 8 is attached to the right side of the electron microscope main body 7 so as to be movable in the horizontal direction.

The tilting base 8 is moved by a tilting axis moving screw 9 attached to both ends thereof and a spring 10a. After aligning the optical axis with the tilting axis 1, the screw 11.1 is moved.
1' to be fixed to the electron microscope main body 7.

A tilted bearing portion 12 is formed at the rear end of the tilted base 8, and a tilted body 13 is rotatably fitted into the tilted bearing portion 12.

Further, a Y control screw 14 and a spring 10b for controlling the sample 21 in the Y direction are incorporated in one side of the inclined body 13, and the tip of each spring 10b has a substantially rectangular cross section at the rear of the sample holding rod holder 16. It abuts the outer wall of the rectangular body portion 33 formed in the shape from both sides.

A spherical receiving portion 15 is formed inside the tip of the inclined base 8, and is configured to receive a spherical portion 17 formed at the tip of the sample holding rod holder 16.

The sample holding rod holder 16 is formed in a hollow shape, and the tip of the sample holding rod 4 is inserted into the hollow so as to protrude.

By turning the Y control screw 14, the sample holding rod receiver 16 is rotated about the spherical portion 17, and the movement of the sample holding rod 4 in the Y direction is controlled.

Next, control the Z direction of sample 21 as shown in Figures 3 and 4.
As shown, this is done by a Z control screw 18 mounted on the ramp 13 at right angles to the Y control screw 14.

The tip of the Z control screw 18, like the Y control screw 14, abuts against the outer wall of the square portion 33 formed at the rear of the sample holding rod holder 16, and the sample holding rod holder 16 is brought into contact with the Z control screw 18. A spring 10C is provided to press it to the side.

Control in the Z direction is performed using the spherical end portion 17 of the sample holding rod receiver 16 as a fulcrum, similar to the control in the Y direction.

Further, the tilt angle is controlled by appropriately rotating the tilting body 13, and at this time, the sample holding rod 4 is also rotated together.

Next, the control in the X direction in this embodiment will be explained. As shown in FIG. , and a lever body 1 that moves this side surface 32 toward and away from the tip of the sample holding rod 4
9 and a floating body that is interposed between the side surface 32 of this lever body 19 and the tip of the sample holding rod 4 and moves the sample holding rod 4 in the X-axis direction in relation to the movement of the side surface 32. .

A central spherical portion 23 of the lever body 19 is supported by a lever holder 22 fitted into a hole drilled in the electron microscope main body 7, and the lever body 19 is supported with the central spherical portion 23 as a fulcrum. It is configured to rotate in the X-axis direction.

That is, the lever body 19 is rotated by the action of the X control screw 6 provided on the outside of the lens barrel of the lever body 19 and the spring 10d.

Further, the floating body interposed between the side surface 32 of the lever body 19 and the tip of the sample holding rod 4 is constituted by a spherical cone body 20 in the present invention.

As shown in FIG. 5, this spherical cone 20 is made by cutting the sphere into a cone so that the approximate center of the sphere is the apex 24 of the spherical cone 20, and a part of the outer surface of the sphere is the base 25. It was formed.

As shown in FIG.
The sample holding rod 4 is held by a cover 26 attached to the cover 26 and a spring 27 inside the cover 26 to prevent it from falling when the sample holding rod 4 is pulled out.

The strength of this spring 27 is such that when the lever body 19 moves, the bottom surface 2
5 is adjusted so that it can roll on the side surface 32 of the lever body 19.

Furthermore, a small hard ball 28 such as a gemstone is fitted into the apex 24 of the spherical cone 20, and this small ball 28 is attached to the sample holding rod 4.
It is in contact with a recess 29 formed at the center of the tip.

The sliding action of the small ball 28 allows smooth rotational movement between the small ball 28 and the abutting surface at the tip of the sample holding rod 4.

To explain the operation of the control in the X direction with such a configuration, first, by turning the X control screw 6, the lever body 19 rotates around the fulcrum, and its side surface 3
2 moves near and far toward the tip of the sample holding rod 4.

First, the case where the side surface 32 of the lever body 19 approaches the tip of the sample holding rod 4 will be described.
As the bottom surface 25 of the spherical cone 20 moves toward the side surface 32
The apex 24 moves in the X-axis direction while pressing the center of the tip of the sample holding rod 4 by the amount that the side surface 32 moves toward the tip of the sample holding rod 4, and as a result, the sample holding rod 4 is moved in the direction of extrusion in the X-axis direction.

Furthermore, to explain the case where the side surface 32 of the lever body 19 is moved away from the tip direction of the sample holding rod 4, the bottom surface 32 of the spherical cone body 20
5 rolls on the side surface 32.

The apex 24 moves in the X-axis direction away from the tip of the sample holding rod 4 by the amount by which the side surface 32 moves away from the tip of the sample holding rod 4.

In this case, since the inside of the lens barrel is maintained in a vacuum state, the center of the tip of the sample holding rod 4 moves following the apex 24, and the sample holding rod 4 moves toward the mirror by the amount that the side surface 32 of the lever body 19 moves. The sample holding rod 4 is inserted into the cylinder, and the center portion of the tip of the sample holding rod 4 is kept in contact with the apex 24 .

Further, in the same way as above, when moving in the Y direction and Z direction, the bottom surface 25 can roll on the side surface 32 of the lever body 19 using the apex 24 of the spherical cone 20 as a fulcrum, so that the bottom surface 25 can roll on the side surface 32 of the lever body 19. Directional movement can also be performed smoothly.

Next, to explain the sample drift in the This will be affected by the increase or decrease in the distance between the position of the bottom surface 25 of the body 20.

Therefore, structurally, by forming the spherical cone 20 small, the above-mentioned distance can be kept small, and sample drift in the X direction can be reduced.

The sample drift in the Y direction and the Z direction is influenced by the distance between each control screw and the tilt axis, but it is small because the distance is kept relatively small.

FIG. 7 shows another embodiment of the sample tilting device according to the present invention.

In this embodiment, the lever body 19 is formed in a triangular shape, with the fulcrum 30 in the middle, the tip of the X control screw 6 is in contact with one side of the lever body 19, and the bottom surface of the spherical cone body 20 is in contact with the side surface 32. 25 are in contact with each other.

This spherical cone 20 is attached to the cover 2 as in the first embodiment.
6 and a spring 27 to be held on the lever body 19.

(This is omitted in FIG. 7) Therefore, by rotating the X control screw 6, the lever body 19 rotates around the fulcrum 30, and the side surface 32 moves toward and away from the tip of the sample holding rod 4. .

And in connection with the movement of said side surface 32, the spherical cone 20
can move the sample holding rod 4 in the X direction.

FIG. 8 shows a third embodiment of the present invention, in which a convex portion 31 is formed at the center of the tip of the sample holding rod 4, and a concave portion into which the convex portion 31 fits is formed into a spherical cone. 20 vertices 24
It is formed and configured.

In addition, in FIGS. 2 and 7, the orientation of the spherical cone 20 is reversed, and a concave portion is provided in the side surface 32 of the lever body 19, with the tip of the sample holding rod 4 being a flat surface, and the apex of the spherical cone 20 is formed in the four portions. 2
4 and the bottom surface 25 may be brought into contact with the plane.

Incidentally, in the present invention, the floating body is constituted by a spherical cone 20 formed by cutting a sphere into a conical shape, but for example, when the Z control is not used, the approximate center of the disk may be set as the apex 24. , and a part of the circumferential side of this disk as the bottom surface 2
The purpose can also be achieved with a fan-shaped floating body formed as shown in FIG.

As described above, according to the sample tilting device for an electron microscope or the like according to the present invention, a spherical cone is provided between the tip of the sample holding rod and the side surface of the lever provided close to the tip of the sample holding rod. Since the configuration is such that the spherical cone is caused to roll by moving the side surface in the X-axis direction, and the sample holding rod is moved in the X direction, the distance between the position of the sample and the side surface of the lever body is It is possible to move in the X direction while keeping the value small.

Therefore, even if the constituent parts of the electron microscope expand or contract due to temperature changes in the outside air or thermal effects from other heating elements, the increase or decrease in the distance between the sample position and the side surface of the lever body can be minimized. , sample drift due to thermal effects can be almost eliminated.

Therefore, high-resolution observation and high-resolution electron microscope photography can be facilitated.

In the conventional example, the shortest distance between the sample and the side surface of the lever body was 100 mm or more, but in the present invention, it is possible to mold the spherical cone to a small size.
Therefore, the distance between the sample and the side of the lever body is set to 10 mm.
The sample drift can be maintained at 1710 or less compared to the conventional example.

Furthermore, the sample tilting device according to the present invention is sufficiently effective when applied not only to electron microscopes but also to similar devices.

[Brief explanation of drawings]

FIG. 1 is a plan sectional view of a conventional sample tilting device, FIG. 2 is a plan sectional view of a sample tilting device according to the present invention, and FIG. 3 is a schematic sectional view taken along line A-A in FIGS. 1 and 2. Fig. 4 is a schematic cross-sectional view taken along the line B-B in Figs. FIGS. 7 and 8 are explanatory diagrams showing essential parts of other embodiments of the present invention. 1... Tilt axis, 2... X control axis, 3...
Connecting rod, 4... Sample holding rod, 7... Electron microscope body, 19... Lever body, 20... Spherical cone, 24...
- Vertex, 25...bottom, 32...side.

Claims (1)

[Claims] 1 Sample holding rod 4 inserted from the X-axis direction perpendicular to the optical axis
and a lever body 19 which has a side surface 32 facing the tip of the sample holding rod 4 at a slightly forward position and moves this side surface 32 near and far in the direction of the tip of the sample holding rod 4; The side surface 32 of the lever body 19 and the sample holding rod 4
In the sample tilting device, the sample 21 is moved in the X direction by a floating body that is interposed between the tip of the sample 21 and the moving body that moves the sample holding rod 4 in the X axis direction in relation to the movement of the side surface 32. The floating body is composed of a spherical cone 20 with an apex 24 at the approximate center of the sphere and a bottom 25 at a part of the outer surface of the sphere, and the tip of the sample holding rod 4 or the lever body 1
A specimen tilting device for an electron microscope or the like, characterized in that the apex 24 of the spherical cone 20 is brought into contact with one of the side surfaces 32 of the spherical cone 9, and the bottom surface 25 is brought into contact with the other.