JPS61107645A - Sample holder of transmission electron microscope - Google Patents

Abstract

PURPOSE:To assure observation of a large-sized sample by providing a rotatable sample mount on the tip end of a sample holder, specifying an axis of rotation of the sample mount in an offset relation to an optical axis of an electron microscope and rotating the sample holder. CONSTITUTION:A sample holder 16 to be inserted into among magnetic poles of an objective lens of a transmission electron microscope consists of a power transmission part 16b having a drive shaft 21 penetrating it and an operation part 16c disposed on the tip end of said power transmission part, and further includes a sample mount 31 provided in said operation part 16c for housing a sample 34, said sample mount being adapted to be rotatable via a sample exchange mechanism comprising gears 22 through 24, 27, and 29. The sample mount 31 is mounted in a state of the center of rotational thereof being eccentric by a distance P with respect to an optical axis 02, and is rotated, whereby the entire region of the sample 34 can be made observable in an observation field areas S. Thus, a large-sized sample can be observed with simple operation by magnifying the field of the sample.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Industrial Application Field The present invention is a sample holding device for an electron microscope, which is particularly capable of observing a large sample over a wide area with simple operation. This invention relates to a sample holding device for a transmission electron microscope.

(2) Prior Art Conventionally, as this type of sample holding device, there is one shown in FIG. 6, for example. 43 in this figure, 1 is the lens barrel of the electron microscope, 2 is a cylinder inserted into the lens barrel 1 from a direction perpendicular to the electron beam axis (hereinafter referred to as the optical axis for convenience), and a screw (not shown) ) is fixed to the lens barrel 1 via. A sample holder 4 is provided inside this cylinder 2 via a spherical part 3.
is held so that it can rotate and move. A sample 6 is held at the tip of the sample holder 4 on the vacuum side via a sample holder 5, and on the atmospheric side, the sample holder 4 is centered on the spherical part 3 in a plane perpendicular to the optical axis. It is held in the cylindrical body 2 so as to be rotatable. Reference numeral 7 denotes a push screw for rotating the sample holder 4, which is screwed into the cylindrical body 2. Further, a spring 8 is provided in the opposite direction of the push screw 7 to maintain engagement between the push screw and the sample holder 4 at all times. Reference numeral 9 denotes a movable rod that is disposed on the extension of the axis of the cylinder 2 and is movably inserted into the lens barrel 1. The vacuum side of the movable rod 9 is connected to the sample via the connecting rod 10. It is connected to the tip of the mounting section 5.

The sample 6 is placed at a position opposite to the barrel 2 with respect to the lens barrel 1.
An operating mechanism 15 for moving in the axial direction is provided, and in this operating mechanism 15, the sample holder 5 can be roughly moved in the X-axis direction. Sample coarse movement screw and sample holder 5
A sample fine movement screw, etc., that moves the sample in the X-axis direction by one step of movement is incorporated. Also, by rotating the push screw 7 and moving it back and forth, the sample holder 4
Since it rotates around the spherical part 3, it is held at the tip.
The sample holder 5 moves in the direction of the arrow C in FIG. Move 1J in the axial direction. As shown in FIG. 7, the sample holder 5 is provided with a stepped structure through-hole 11 for setting the sample 6, penetrating in the light direction, and a stepped portion 11a of the through-hole 11. Sample mesh 1 on top
2 is placed, a presser plate 13 is placed on top of the presser plate 13, and a presser plate 13 is placed on the presser plate 13
The sample fixing ring 14 is fitted from above, and the sample 6 is attached to the sample 1.
' It is designed to be firmly fixed on the F1/IN router 4.

(3) Problems that the invention attempts to solve
.

By the way, the size of the mesh that holds the sample in an electron microscope is generally such that the outer diameter d is 3 mm (-) and the effective diameter of the mesh is 2 mm. 2mm on each side according to the effective diameter of
It is designed and manufactured so that it becomes a square (
(See Figure 8). However, in recent years, the need for ITA dormitories for large samples has increased, especially in the biological field.
Transmission electron microscopes have appeared that are capable of observing large samples using a so-called jumbo mesh. When such a large sample mesh is used as a sample holder for an electron microscope, the size of the sample 6 becomes larger than the observation field area S of the electron microscope, as shown in FIG. Point A protrudes from the observation viewing field S when the optical axis and the center of the sample mesh 12a are aligned. In the conventional electron microscope, the position of the sample mesh 12a is moved in the X-axis and Y@force directions by the linked operation of the sample holder 4 and the actuator 4M15 described above, and the observation area of the sample 6 is moved. The entire sample area is covered.

However, when a large sample mesh 12a is used, the movement stroke or rotation distance of the sample holder 4 becomes large when observing the sample 6.
It is necessary to make one structure larger.

Then, in the electron microscope, the sample insertion part was tested with 1 small rudder 4.
In addition to the operating mechanism 15, there are also other parts such as a diaphragm device, etc.
Because the %IA sensor to prevent sample contamination or the objective lens, etc. are installed close to each other, the overall size of the sample holding device becomes larger, making it necessary to change the overall mechanism around the objective lens. I end up.

Does the present invention solve these conventional problems? The purpose of this was to create a sample holder S that allows the entire range of the specimen to be placed within the field of view when observing large specimens. The purpose of this invention is to solve the above-mentioned conventional problems.

(4) Means for Solving the Problems In order to achieve the above object, the present invention has a sample holder tip portion of a sample holding device that is rotatable in a plane that is perpendicular to the IE end line llff1+. Trial 1': Install one sample holder, rotate the central axis of rotation of this sample stand to the electron beam +1111 by a predetermined distance with 4L, and mirror the sample holder.
The objective lens is placed between the magnetic poles of the microscope, and by rotating the sample stage, the entire area of the sample is placed within the observation field of view.

(5) Function First, when the sample holder is inserted between the magnetic poles of the objective lens in the lens barrel, the i! A field of view area (field of view) is positioned. This condition is shown in FIG. 4 and will be explained in detail later. When the sample stage is rotated with the observation field of view set at such a biased position, the sample rotates together with the sample stage, and each part of the sample enters and exits the observation field of view one after another. When the sample stage rotates once, the observation field of view IJi! The sample range passing through S is essentially the observation field of the electron microscope. For this reason, a large observation field 19 is provided for the designed field of view determined by the design of the electron microscope, that is, the part shown as the rectangular observation field area S in the above explanation, and it is possible to accommodate larger specimens. be able to. If it is not possible to cover the entire range of observation field area S by one rotation of the sample stage, repeat the operation of shifting the sample holder by the distance in the longitudinal direction and rotating the sample holder again. .

(6) Examples Embodiments of the present invention will be described below with reference to FIG. 4.

1 to 4 are diagrams showing a first embodiment of the wooden block diagram. Of these figures, Fig. 1 is a side view of the entire sample holder 1 [5 inserted between the objective lens magnetic poles, and Fig. 2 is an enlarged view of the tip of the sample holder 16. 3 is an enlarged plan view, and FIG. 3 is a side sectional view taken along the knee line 2 in FIG. 2.

In this embodiment, the sample holder 16 serves as a base for moving the sample holder 16 in and out of the lens barrel 1, and also includes an operation section 16a that controls operations such as tilting the sample holder 16 or changing the sample. , , operation section 16a
The operating portions 16a1. :
Transmit power to J3 i2 t f) 4 force transmission +; l! 1
6b, and an actuating part 16c carved at the tip of the power transmitting part 16b. A knob 2o for performing sample switching operations and a positioning spindle 37 for positioning the sample holder when coupled to the lens barrel are attached to the operating portion 16a.

A through hole 038 is formed along the longitudinal direction of the holder main body 419 corresponding to the power transmitting portion 16b, and a drive shaft 21 for transmitting power from the operating portion 16a to the operating portion 16c is formed within the through hole 38. is loaded. Also,
A mechanism accommodating section 18 is formed in one holder main body corresponding to the operating section 16G, and a sample conversion mechanism 17 is provided within this mechanism accommodating section 18. The tip of the drive shaft 21 provided in the power transmission section 16b is connected to the sample conversion mechanism 17, and power is transmitted to the sample conversion mechanism 17. The sample conversion mechanism 17 has a first
The bevel gear 22 meshes with the first bevel gear 22, and the drive shaft 2
A second bevel gear 2 that converts the power transmission direction by 90 degrees by 1.
3, the wheel portion and the shaft portion are integrally formed, and the second
A first spur gear 24 is rotatably attached to the bevel gear 23 and the holder body 19 and rotates together with the second bevel gear 23, and a structure similar to the first spur gear 24 is fixed. The second spur gear 27 is rotatably attached to one holder body by a member 28 and rotates by meshing with the first spur gear 24, and is rotatably attached to the holder body 19 by a fixing member 30. , i meshes with the second spur gear and rotates
It consists of an IJ wheel 29 and a sample stand 31 which is rotatably attached to one holder main body by a fixing member 32 and rotates by meshing with a third spur gear. It consists of a gear having the same base configuration as the third spur gear 24, 27, 29, and as is clear from FIGS. 2 and 3, the sample stage 31 has a A specimen holding portion with a diameter of <5 mm and a specimen receiving hole 33 are formed through the specimen.

The sample storage hole 33 is formed into a rectangular cross-sectional shape in the upper half of the sample storage hole 31, and a d-type D-shaped hole in the lower half with a tapered shape that gradually expands toward the bottom. It has become a mouth. A large sample mesh 12a holding a large sample 34 similar to that described in the explanation of FIG. 9 is accommodated in the stepped portion of the sample accommodation hole.
A holding plate and a sample fixing ring 35 for fixing 2a are fixed. On the other hand, a tapered through hole 36 centered on the optical axis 02 is formed in the lower portion of the sample stage 31 of the holder body 19, which corresponds to the actuating portion 16c.

The sample stage 31 is connected to the operation section 16a of the sample holder 16.
By rotating the knob 20 attached to the sample table, the sample table 31 rotates clockwise in FIG. By adjusting the gear V ratio of the various gears forming the structure 17, the rotation speed N1 of the knob and the rotation speed N2 of the sample stage 31 can be freely varied.For example, the gear ratio such that N2/N1=1 can be adjusted. If you turn the knob once, you can change the field of view over one rotation of the sample 34.Moreover, the direction of rotation of the sample stage 31 during this rotation 1'+:1) ;t ll:'+ 71 direction, counter-time i
The magnification can be freely selected in the t direction, for example, one sample 34 at a magnification of li5! After sensing, for example, pick 20
rotated in different directions from each other L! Since it is possible to switch the field of view to observe a sample part that is completely distorted, even if the sample 34 is relatively large, it is possible to lift the sample holder by swinging or tilting the sample holder. It is possible to perform trial observations over a wide field of view.

The sample holder 16, which has such a configuration, is placed between the magnetic poles of the objective lens in the lens barrel 1 of the electron microscope, so that its center of rotation 111O1 is at a distance from the optical axis 02, as shown in FIG. 4(a). It is installed eccentrically by P. In this embodiment, the rotation center of the sample holder 16[, L sample stage 31・N+01
is drawn eccentrically by P in the X-axis direction; □′ direction with respect to the optical axis 02, or eccentrically by a predetermined distance in the Y direction, or by a predetermined distance in the X-axis and Y-axis directions. It may be eccentric by a distance of . The eccentricity IP in this example is set to be 25M when the length of one side of the observation field area S of the electron microscope is 2M.
6. When installed, the rotation center axis 01 of the sample stage is in the observation field area S.
If it is located within the range, it is convenient to cover the entire area of the sample 34.

Therefore, in the sample holding device for an electron microscope according to this embodiment, when the sample holder 16 is simply set in the lens barrel 1 of the electron microscope, the electron microscope is As shown in FIG. 4(a), the observation field area S is only located at the back right corner of the entire sample 34, but when the knob 20 is rotated in the clockwise direction or the counterclockwise direction. The sample 34 rotates around the rotation center l11101 together with the sample stage 31, and the other area of the sample 34 comes into the observation field of view.As a result, the entire sample can be observed without the sample holder 16 WIJ 37F'J can be performed without rocking or spinning motion.

Considering the expansion of the observation field of view caused by J due to the rotation of the sample stage 31, for example, in this embodiment, the observation field of view becomes J due to the rotation of the sample stage 31, π((P+M)+M) = 6.3M +6.3PM t 3 P2, and if the eccentricity ff1P becomes the minimum bean O, the size of the observation field becomes 6.3M. This is the till! of the electron microscope drawn as a square in Figure 4. Ii tJ2 field β
The area of area S is 4M.Compared to this, it is approximately 60%
It means that the field of vision has increased.

Also, suppose that the value of M that defines the observation field area S of the electron microscope is 1 (mm>), and the eccentricity ff1P = 0.8 (mm).
If i, then substitute each value into the above formula and get 752
The field range is approximately 3.3 ('8).

In this way, the sample II holder 16 inserted into the lens barrel 1 on the instep is slightly rotated by the knob provided at its base end. +! Since the field of view is increased, very effective results can be obtained for observing large samples.

In the case shown in FIG. 4 (a), if the rotation center axis 01 of the sample stage 37 is offset by P with respect to the optical axis 02, the entire range of the sample 34 can be covered by rotating the sample stage 31 once. It can be kept within the field of view.However, as shown in Figure 4 (
As shown in b), the sample 34 becomes even larger, and even if the rotation center axis 01 of the sample stage 31 is decentered by P with respect to the optical axis 02 as described above, the sample 34 may still remain.

When observing such an extremely large sample 45, once the sample stage 31 is rotated in the state of eccentricity ff1P, the sample holder 6 is further shifted by a predetermined length in the longitudinal direction, and the sample stage 31 is rotated again. The entire area can be included within the observation field of view.

FIG. 5 is a diagram showing a second embodiment of the present invention.

In this embodiment, as in the first embodiment, the sample conversion mechanism 17 includes various gears 22°, 23.2
4.27.29 and a sample stage 31, but in addition, a second sample stage 40 of the same type as the sample stage 31 is rotated at the tip side of the actuating part 16C compared to the sample stage 31. It can be installed easily. This second sample stand 40 is made of a spur gear of N construction similar to the sample stand 31, receives power transmission from the knob 20 by meshing with the sample stand 31, and rotates the rotation center axis 03. It can be rotated clockwise or counterclockwise around the center.A sample mesh 12a1 similar to that in the first embodiment is mounted on the second sample stage 40.
Is the holding plate and sample fixing ring gQF? A large sample 3/la is placed on the sample mesh 12a. Further, the sample holder 16 is provided with a rough guide for moving the sample holder 16 in its longitudinal direction @ line direction (corresponding to the X'ti11 direction). /I mechanism (not shown) is connected, and by operating this rough on mechanism, the sample holder 16 is moved to the first position.
The observation position, that is, the position where the sample stage 31 corresponds to the observation field of view of the microscope, and the second observation position, that is, the second sample stage 40/i: a position that corresponds to the observation field of view of the microscope. By moving the sample 34 installed on the sample stand 31 and the second sample stand 401. : 1llll between installed sample 34a! You can perform a switching operation to the dormitory position.

For example, in FIG. 5, when the sample 34 placed on the sample stand 31 is at the observation position, if you want to see the sample 34a placed on the second sample stand 40, The rotation center axis 03 is at a predetermined distance (
For example, the sample holder 16 may be roughly moved in the X-axis direction so that it comes to a position eccentric by P) similar to that in the first embodiment. After moving the sample holder 16 in the X-axis direction, Shun transmits the power to the sample converter [17] by rotating the knob 20, and by rotating the second sample stage 40, the large-sized The entire extent of the sample 34a can be placed within the viewing field of the microscope. Therefore, according to the second embodiment, by using the two sample stands 31 and 40, it is possible to move a plurality of large samples to the observation position with an extremely simple operation and to observe the entire large sample. This makes it possible to perform I-inspection of large samples using a transmission electron microscope, which was previously unimaginable.

(7) As described in detail, according to the present invention, a rotatable sample stage is installed at the tip of the sample boulder, and the central axis of rotation of the sample stage is aligned with respect to the optical axis of the electron microscope. The observation field of the electronic microscope was expanded by installing the sample holder eccentrically by a predetermined distance and rotating the sample stage.
The structure is extremely simple, and it has become possible to observe a large sample v+ by simple operation. Furthermore, a rotatable sample stage can be used as a sample holder? ! By providing two or more of them, a great advantage is obtained that a plurality of large samples can be observed with a wide field of view.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a sample holder used in a sample holding device for an electron microscope according to a first embodiment of the present invention, and Fig. 2 shows a tip portion of the sample holder used in an iH according to the first embodiment. FIG. 3 is an enlarged plan view taken along line II-N in FIG. 2, and FIG. (a) A plan view showing the installation state of the sample holder.
5 is a diagram showing the state during observation of a large sample, (b) is a diagram showing the state during observation of an extremely large sample, and FIG. 6 is a diagram showing a conventional sample holding device for an electron microscope; FIG. 7 is an exploded perspective view showing an enlarged sample setting portion of a sample holder used in a conventional electron microscope sample holding device; FIG. 8 is a plan view of the tip of the sample holder shown in FIG. 7, and FIG. 9 is a diagram showing the installation state of the sample holder with respect to the optical axis when observing a large sample using the sample holder of a conventional electron microscope. It is. 1... Lens barrel 2... Cylindrical body 3... Spherical part 4.16... Sample holder 5... Sample mounting part 6. 34. 34a, 45...Sample 12.128.
...Sample mesh 17...Sample conversion mechanism 31...Sample stand 40...
Second sample stage Ql, 03...Rotation center axis o2...Optical axis (electron beam @)
call ring

Claims (1)

[Claims] 1) In a sample holding device in which a sample holder is inserted between magnetic poles of an objective lens in a lens barrel in which an electron beam path is formed in a direction perpendicular to the electron beam axis, A sample stage is installed so as to be rotatable in a plane substantially orthogonal to the electron beam axis, and a sample holder is installed in the lens barrel with the rotation center axis of the sample stand eccentric by a predetermined distance with respect to the electron beam axis. A specimen holding device for a transmission electron microscope, characterized in that the field of view for specimen observation can be changed by rotating the specimen stage. 2) The sample holding device for a transmission electron microscope according to claim 1, wherein when the sample holder is installed, the central axis of rotation of the sample stage is set within the observation field of the electron microscope. 3) The sample holder is installed in such a way that the central axis of rotation of the sample stage is set within the observation field of view of the electron microscope, and the position where the central axis of rotation is set outside of the observation field of view of the electron microscope. A sample holding device for a transmission electron microscope according to claim 1. 4) A plurality of sample stands are provided on the sample holder, and the rotation center axis of each sample stand is eccentric by a predetermined distance with respect to the electron beam axis. A sample holding device for the transmission electron microscope described above.