JP2000100365A - Electron microscope sample support apparatus and method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable a sample, which is difficult to be repeatedly held in a predetermined posture, to be held on a sample table without damaging the sample. A rod-shaped sample holder having an extremely fine needle-like sample at one end is elastically held on a sample base so that the tip of the needle-like sample is located at the intersection of the X axis and the electron beam optical axis. Have been. The needle-shaped sample 16A is welded to one end of the sample holder 16. The sample stage 14 is electrically insulated from the rotating body 7 and is rotatable concentrically with the X axis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for supporting a sample of an electron microscope, and more particularly, to a method for holding an ultra-thin or ultra-fine sample easily and easily, and for rotating the sample. The present invention relates to a method and an apparatus for supporting a sample of an electron microscope capable of observing a microstructure in a high temperature state and performing local analysis of its composition.

[0002]

2. Description of the Related Art In general, as an atomic level analysis method in a bulk material such as a steel material, an Atom Probe Ion Field Microscope is used.
: Hereinafter, abbreviated as AP-FIM);
Transmission Electron Microscope (TransmissionElectorn Microscope:
Hereinafter, abbreviated as TEM) is typical. According to the analysis by AP-FIM, the length is about 3 to 5 mm,
Wire diameter about 0.1mm (radius of curvature at the tip is 100nm or less)
In the TEM analysis, a portion having a thickness of 0.1 μm or less through which the electron beam can pass is observed at the tip of the needle sample. For example, application for Japanese Patent Application No. 4-341036 (see)
As described in the above, the same sample can be held in the same posture in each device.

[0003]

In order to use each analysis technique together, it is necessary to be able to hold the same sample in the same posture in each device, and to remove a minute portion to be analyzed when mounting the sample. Don't do anything that damages you. For example, as described in Japanese Patent Application No. 4-341036, when a sample is clamped on a sample stage, it is inserted through the narrow space of the mounting hole on the sample stage. Attention was needed. Further, it was impossible to observe the opposite side of the observation portion without breaking the vacuum, and there was no means for heating the observation portion.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to make it possible to easily and easily hold a sample, which is difficult to hold repeatedly in a predetermined position, in the same position and to observe the sample. That is, the part can be rotated by 360 °, and heating can be performed during observation with a TEM.

[0005]

Means for Solving the Problems In order to achieve the above object, the present invention is characterized in that the following means are taken.

(1) A wide space can be used by inserting parallel notches through notches provided in the first and second rotating members (sample table).

(2) Since the sample can be rotated by 360 °, it can be observed all around the part to be analyzed.

(3) Since the sample can be rotated from outside the vacuum, any rotation can be performed while observing.

(4) A smooth rotation can be obtained because the sliding portion of the rotating body is made of a resin or the like having a low friction coefficient.

(5) Since the sample is configured to be heated, the microstructure can be observed while heating.

That is, according to the above configuration (1), it is possible to attach and detach the ultra-thin or ultra-fine sample without damaging the observation site of the ultra-thin or ultra-fine sample which is difficult to hold in a predetermined posture, and to set the dimensions of the sample holder. Is 20-30mm long,
The wire diameter can be reduced to about 1 mm, which facilitates handling.

According to the above configuration (2), the analysis on the opposite side of the observation site can be easily performed.

According to the above configuration (3), the rotation operation can be easily performed while observing without breaking the vacuum.

According to the above configuration (4), the rotational movement during the observation is smooth.

According to the above configuration (5), observation and analysis at the atomic level of the steel material in a heated state can be performed, and no contamination is attached during the observation.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a sample holder according to an embodiment of the present invention, FIG. 2 is an enlarged plan view near the sample stage of FIG. 1, and FIG. 3 is a sectional view taken along line aa of FIG. It is. In FIG. 1, a base tube 3 is attached to a wall 2 constituting a vacuum chamber 1 in a vacuum-resistant manner. A swing motion shaft 6 that swings around the spherical body portion 4 by the swing motion mechanism 5 is inserted into the base cylinder 3 in a vacuum-resistant manner. The hollow shaft-shaped rotator 7 is disposed along a first central axis (hereinafter, referred to as an X axis) orthogonal to the electron beam optical axis 8, passes through the oscillating motion axis 6 from the outside of the vacuum chamber 1 to the inside. To the vacuum.

The outer frame 7B of the thin plate at the tip of the rotating body 7 is located between the upper pole piece 9 and the lower pole piece 10 of the objective lens. The current introduction axis 11 is the guide 1
2, a knob 13 is provided at the outer end of the current introduction shaft 11, and is connected to a sample stage 14 having a second central axis on the opposite side. The sample stage 14 has the guide 1
5 and is introduced into the hollow hole of the rotating body 7 concentrically with the first center axis in a vacuum-resistant manner. There is a gap 14B as a non-contact portion in a part between the rotating body 7 and the sample stage 14.

Since the guides 12 and 15 are formed of an insulator, the current introduction shaft 11 and the sample table 14 are rotated by turning the knob 13 to rotate the sample table 14 while keeping the rotor 7 electrically insulated. be able to. A rod-shaped sample holder 16 having a needle-shaped sample 16A for observation at one end is held on the sample stage 14 such that the tip of the needle-shaped sample 16A is positioned on the electron beam optical axis.

The rod-shaped sample holder 16 is composed of a needle-shaped sample 16A having a length of 3 to 5 mm and a wire diameter of 0.1 mm or less, and a holding portion 16B having a length of 25 to 30 mm and a wire diameter of about 1 mm. The needle-shaped sample 16A is fixed to one end of the holding portion 16B by an appropriate means such as welding. The rotating body 7 and the sample table 14 are provided with notches 7A and 14A as insertion holes for attaching the rod-shaped sample holder 16, and when the rod-shaped sample holder 16 is inserted through the notch 7A and the notch 14A. The sample table 14 is elastically held by a spring action.

A ground terminal 17 is screwed to the outer frame 7B of the rotating body 7 at right angles to the central axis, and the ground terminal 17 elastically contacts the vicinity of the tip of the needle-like sample 16A to electrically connect the same. Conducted. The tip of the outer frame 7B of the rotating body 7 is
The tip of 6A is in contact with the sample positioning member 19 via the pivot 18 so that the tip of 6A is always accurately positioned at the intersection of the electron beam optical axis 8 and the X axis. A variable resistor 21 and a power supply 22 are connected to the knob 13 via a wiring 20. When power is supplied from the power supply 22, the current introduction shaft 11 and the sample table 1 are turned on.
4. A current flows through the needle-shaped sample 16A via the rod-shaped sample holder 16.

In the sample holder having such a configuration, when the rod-shaped sample holder 16 is first inserted outside the vacuum through the notch 7A of the rotating body 7 and the notch 14A of the sample base 14, the center of the rotating body 7 The rod-shaped sample holder 16 is stopped at a position where the centers thereof coincide. Needle-shaped sample 1
6A is inserted into the vacuum, and the vacuum chamber 1 is inserted.
When the rotator 7 is rotated clockwise or counterclockwise outside the sample, the sample table 14 supported by the rotator 7, that is, the needle-shaped sample 16A, rotates in the same direction around the X axis.

However, the upper pole piece 9 of the objective lens
The angle at which the outer frame 7B of the rotating body 7 does not come into contact with the narrow gap between the outer pole 7 and the lower pole piece 10 is ± 20 °.
About ± 30 °. When the knob 13 is rotated, the sample table 14 and the needle-shaped sample 16A
Is rotated, and the needle-like sample 16A can be rotated by 360 ° because the wire diameter is about 0.1 mm or less.
Even when the needle-shaped sample 16A rotates, the vicinity of the tip of the needle-shaped sample 16A is in elastic contact with the ground terminal 17 and is electrically connected.

Here, when a voltage is applied by the power supply 22, the variable resistor 21, the knob 13, the current introduction shaft 11, and the sample table 1
4. An electric current flows through the needle-shaped sample 16A through the rod-shaped sample holder 16, and drops to ground through the ground terminal 17. Since the needle-shaped sample 16A has a wire diameter of 0.1 mm or less, the electric resistance is large and heat is generated, and the sample is heated at a high temperature. Since the nearby observation site is also heated by heat conduction, it is possible to observe a fine structure in a high temperature state. When the current is controlled by the variable resistor 21, the heating temperature can also be controlled.

According to the above configuration, the needle-shaped sample analyzed by the AF-FIM is mounted on the sample base of the TEM (or vice versa), so that the same local area can be observed from the same direction. In the present embodiment, the notches 7B and 14A are provided with large dimensions on the sample table 14, which is the first rotating body 7 and the second rotating body, so that the length of the rod-shaped sample holder 16 is easy to handle. It can be made long enough.
In the above-described embodiment, an example was described in which an extremely fine sample is used as a sample that is difficult to repeatedly hold in a predetermined posture.
The present invention is not limited to this, and may be an extremely thin sample.

[0026]

As described above, according to the present invention, the following effects can be achieved.

(1) Since an ultra-thin or ultra-thin sample integrated at one end of the sample holder can be held on the sample table using a wide space, the sample can be inserted and removed without damaging the fine tip of the needle-shaped sample. It will be easier.

(2) Since the sample can be rotated by 360 ° around the X axis, it can be analyzed over the entire circumference.

(3) Since the sample can be rotated from outside the vacuum, it can be freely rotated and stopped while observing.

(4) Since the sliding portion of the rotating body is in contact with a member made of resin or the like having a small friction coefficient, a smooth rotational movement can be obtained.

(5) Since the sample can be heated, the microstructure can be observed and analyzed while heating.

(6) When the part to be observed is heated to 200 to 300 ° C., outgassing from the inner wall of the vacuum and other impurities can be observed in a clean state without adhering.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a sample holder according to an embodiment of the present invention.

FIG. 2 is an enlarged plan view near the sample stage of FIG. 1;

FIG. 3 is a sectional view taken along line aa of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... vacuum chamber, 2 ... wall, 3 ... base cylinder, 4 ... spherical body part, 5 ... oscillating motion mechanism, 6 ... oscillating motion axis, 7 ... rotating body, 8 ... electron beam optical axis, 9, 10 ... Pole piece of objective lens, 11: current introduction axis, 12, 15: guide, 13: knob, 14:
Sample table, 16: rod-shaped sample holder, 17: ground terminal, 1
8: pivot, 19: positioning member, 20: wiring, 21
... variable resistor, 22 ... power supply.

Continued on the front page (72) Inventor Hideki Abe 882, Momo-shi, Hitachinaka-shi, Ibaraki F-term in Measuring Instruments Division, Hitachi, Ltd. 5C001 AA01 AA05 BB01 CC03

Claims (9)

[Claims] An electron microscope sample supporting apparatus for integrally observing an extremely thin or ultra-fine sample, which is difficult to hold in a predetermined position, at one end of a sample holder having a shape for holding in a predetermined position. Is inserted into a tip of a first rotating body rotatable about a first central axis substantially orthogonal to the electron beam optical axis by substantially parallel movement from a position parallel to the first central axis and held. A sample supporting device for an electron microscope characterized by the above-mentioned. 2. A sample wherein the sample is held on a second rotating body having a center axis concentric with the center axis of the first rotating body, and the sample is rotated independently of the rotation of the first rotating body. 2. The sample supporting device for an electron microscope according to claim 1, further comprising a rotating mechanism. 3. The electronic device according to claim 2, wherein the sliding portion of the second rotating body that contacts the first rotating body is formed of a thermal and electrical insulator having a low coefficient of friction. Microscope sample support device. 4. The apparatus according to claim 1, wherein the first rotating body and the second rotating body have cutouts at positions where the sample holder is inserted. Item 3. The sample support device for an electron microscope according to Item 1. 5. The electronic device according to claim 1, wherein an operation knob for rotating the sample is provided at an outer end of the first rotator so that the sample can be rotated from outside a vacuum. Microscope sample support device. 6. A conductive member that comes into contact with the sample from a position substantially perpendicular to the center axis through an intersection of the central axis shared by the first and second rotors and the optical axis of the electron beam. 4. A sample supporting apparatus for an electron microscope according to claim 3, wherein a conductive member is provided so that the sample falls to the ground, and an electric current is applied to the sample to heat the sample. 7. A sample supporting method for an electron microscope for observing an ultra-thin or ultra-fine sample, which is difficult to hold in a predetermined posture, wherein the sample holding member has a shape for holding the sample in a predetermined posture. The sample support of the electron microscope is characterized in that the sample is held in a predetermined position and orientation by rotating the sample by 360 ° by integrating the sample holder, inserting the sample holder by parallel movement, and appropriately holding the sample holder. Method. 8. The apparatus according to claim 7, wherein the sample holder is elastically held between the second rotating body.
The method for supporting a sample of an electron microscope according to the above. 9. The method for supporting a sample of an electron microscope according to claim 7, wherein a conductive member is brought into contact with the sample from a position orthogonal to the sample so that an electric current can be applied to the sample to heat the sample.