KR102649424B1 - Electron microscope sample holder with temperature control of the sample using peltier element and electron microscope having the same - Google Patents

Abstract

The present invention relates to an electron microscope sample holder having a temperature control function and an electron microscope equipped with the same. More specifically, the present invention relates to a sample holder for fixing a sample of an electron microscope in a vacuum chamber, a barrel penetrating a side wall of the vacuum chamber, a grid seating portion provided at one end of the barrel, and a grid mounting portion coupled to the grid seating portion. It relates to an electron microscope sample holder including a first Peltier element, a second Peltier element provided at the other end of the barrel, and a heat transfer rod connecting the first and second Peltier elements to each other.

Description

Electron microscope sample holder capable of controlling the temperature of the sample using a Peltier element and an electron microscope equipped with the same {ELECTRON MICROSCOPE SAMPLE HOLDER WITH TEMPERATURE CONTROL OF THE SAMPLE USING PELTIER ELEMENT AND ELECTRON MICROSCOPE HAVING THE SAME}

The present invention relates to a sample holder for an electron microscope and an electron microscope equipped with the same. More specifically, it relates to a sample holder for an electron microscope capable of controlling the temperature of a sample through a Peltier element and an electron microscope equipped with the same.

An electron microscope is a microscope that uses high-speed accelerated electrons as a light source and observes the sample by detecting the movement of electrons in a vacuum. It includes a transmission electron microscope (TEM) and a scanning electron microscope. , hereinafter referred to as SEM) is a representative example.

The main difference between SEM and TEM is that SEM generates images by detecting electrons reflected by the interaction with the electron beam scanned from the surface of the sample, while TEM generates images by detecting electrons transmitted through the sample. As a result, SEM is capable of analyzing the surface of a sample at the microscale, while TEM is capable of analyzing the structure at the nanoscale, so there is a difference in the content and resolution of the analysis.

However, because electron microscopes use accelerated electrons as a light source, they are very sensitive to the external environment. Analysis is performed in a vacuum state within a vacuum chamber, and has the characteristic of being sensitive to external air, light, noise, and subtle vibrations. Therefore, in an electron microscope, an electron gun for emitting electrons and a sample are located in a chamber that can maintain a vacuum.

In addition, experiments using electron microscopes are generally conducted at room temperature, but in special conditions that require low temperature, the sample is cooled. In order to cool the sample, the coolant for cooling the sample is manually changed periodically or circulated through a coolant pump. It is common to cool it down.

However, this method of using coolant has a problem in that it causes subtle vibrations in the sample, which may affect the observation results. Therefore, due to the nature of electron microscopes, which are vulnerable to vibration, research on sample cooling technology that minimizes vibration excluding vibration elements is required.

The problem to be solved by the present invention is to provide a device that can cool a sample in an electron microscope.

Another problem to be solved by the present invention is to provide a device that minimizes vibration when cooling a sample for an electron microscope.

Another problem that the present invention aims to solve is to provide a device that can continuously and quickly control the temperature of a sample in an electron microscope.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

In order to solve the above or other problems, according to one aspect of the present invention, there is provided a sample holder for fixing a sample of an electron microscope in a vacuum chamber, comprising: a barrel penetrating a side wall of the vacuum chamber; A grid seating portion provided at one end of the barrel; a first Peltier element coupled to the grid seating portion; a second Peltier element provided at the other end of the barrel; and a heat transfer rod connecting the first and second Peltier elements to each other.

The material of the heat transfer rod may be oxygen-free copper.

Each of the first and second Peltier elements may have a low temperature section and a high temperature section.

The low temperature portion of the first Peltier element may be fastened to the grid seating portion, and the high temperature portion of the first Peltier element may be fastened to the heat transfer rod.

The low temperature part of the second Peltier element may be coupled to the heat transfer rod, and the high temperature part of the second Peltier element may be exposed to the outside of the vacuum chamber.

It may further include a heat sink, and the high temperature portion of the second Peltier element exposed to the outside may be coupled to the heat sink to dissipate heat.

The effect of the electron microscope sample holder according to the present invention will be described as follows.

According to at least one of the embodiments of the present invention, there is an advantage that a sample for an electron microscope can be effectively cooled.

Additionally, according to at least one of the embodiments of the present invention, there is an advantage that vibration that may occur when cooling a sample in an electron microscope can be minimized.

In addition, according to at least one of the embodiments of the present invention, there is an advantage in that the time required to control the temperature of the sample in the electron microscope can be shortened as much as possible and a uniform temperature can be maintained.

Further scope of applicability of the present invention will become apparent from the detailed description that follows. However, since various changes and modifications within the spirit and scope of the present invention may be clearly understood by those skilled in the art, the detailed description and specific embodiments such as preferred embodiments of the present invention should be understood as being given only as examples.

Figure 1 shows a conceptual diagram of a sample holder 100 for mounting a sample on a transmission electron microscope (TEM) according to an embodiment of the present invention.
Figure 2 is a diagram showing a Peltier element 104 according to an embodiment of the present invention.
Figure 3 is a diagram showing a perspective view of the sample holder 100 according to an embodiment of the present invention.
Figure 4 is an enlarged view of the tip portion of the sample holder 100 according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating the other end of the barrel 101 exposed to the outside of the TEM chamber 110 according to an embodiment of the present invention.

Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted. The suffixes “module” and “part” for components used in the following description are given or used interchangeably only for the ease of preparing the specification, and do not have distinct meanings or roles in themselves. Additionally, in describing the embodiments disclosed in this specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed descriptions will be omitted. In addition, the attached drawings are only for easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the attached drawings, and all changes included in the spirit and technical scope of the present invention are not limited. , should be understood to include equivalents or substitutes.

Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

Singular expressions include plural expressions unless the context clearly dictates otherwise.

In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Figure 1 shows a conceptual diagram of a sample holder 100 for mounting a sample on a transmission electron microscope (TEM) according to an embodiment of the present invention. Figure 1 shows a cross-sectional view of the sample holder 100 according to an embodiment of the present invention as seen from above, but the content of the present invention will not be limited by the viewing direction.

Figure 2 is a diagram showing a Peltier element 104 according to an embodiment of the present invention. In the description of the present invention, the first and second Peltier elements 104-1 and 104-2 are collectively referred to as the Peltier element 104.

Figure 3 is a diagram showing a perspective view of the sample holder 100 according to an embodiment of the present invention.

Figure 4 is an enlarged view of the tip portion of the sample holder 100 according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating the other end of the barrel 101 exposed to the outside of the TEM chamber 110 according to an embodiment of the present invention.

Hereinafter, it will be described with reference to FIGS. 1 to 5.

The sample holder 100 according to an embodiment of the present invention includes a barrel 101, a grid seat 102, a grid 103, first and second Peltier elements 104-1 and 104-2, and a heat sink. It may be configured to include (105), a heat transfer rod 106, a branch pipe 302, a control unit 501, a sensing unit (not shown), and a feedthrough 301. The components shown in FIG. 1 are not essential for implementing the sample holder 100, so the sample holder 100 described herein may have more or fewer components than those listed above. there is.

The sample holder 100 includes a tubular barrel 101 long enough to extend from the outside of the TEM chamber 110 to a predetermined position inside the TEM chamber 110, and a grid seat 102 connected to one end of the barrel 101. ) is composed of. The barrel 101 is provided in a form that penetrates the side wall of the TEM chamber 110, so that one end of the barrel 101 is located inside the TEM chamber 110 and the other end of the barrel 101 is outside the TEM chamber 110. may be exposed.

In addition, the TEM chamber 110 and barrel 101 according to one embodiment of the present invention are proposed to form a closed area as a whole. A vacuum can be maintained in the sealed area, and in order to achieve sealing, the area where the barrel 101 and the side wall are connected can be sealed to prevent air from passing through.

The grid seating portion 102 forms an accommodating space for accommodating the grid 103 for fixing the sample. The grid seating portion 102 may be made of a material with high thermal conductivity, and as a specific example, may be made of oxygen-free high thermal conductivity (OFHC). The grid seating portion 102 can be controlled to lower the temperature of the sample by being cooled by a Peltier element, which will be described later.

The grid 103 is a thin net that supports the slice, is circular with a diameter of about 3 mm, and can be classified into various types depending on the number of holes.

And, for effective observation of the sample, the interior of the TEM chamber 110 and the interior of the barrel 101 may be maintained in a vacuum.

The sample holder 100 according to an embodiment of the present invention may include first and second Peltier elements 104-1 and 104-2.

The first Peltier element 104-1 is configured to cool the grid seating portion 102 in order to control the temperature of the sample to be lowered.

Each of the first and second Peltier elements 104-1-1 and 104-2 may have a low temperature part 201 and a high temperature part 202 as shown in the drawing, and the first and second Peltier elements 104 When power is provided to -1, 104-2), the temperature of the low temperature part 201 decreases, and in return, the temperature of the high temperature part 202 increases.

Hereinafter, the low temperature part of the first Peltier element 104-1 is indicated by 201-1 and the high temperature part by 202-1, and the low temperature part of the second Peltier element 104-2 is indicated by 201-2 and the high temperature part by 202-2. Display.

That is, the low-temperature portion 201-1 of the first Peltier element 104-1 may be in contact with the grid seating portion 102 to cool the grid seating portion 102. When the grid seating portion 102 is cooled by the low temperature portion 201-1 of the first Peltier element 104-1, the high temperature portion 202-1 of the first Peltier element 104-1 conversely generates heat. It will be done.

The first Peltier element 104-1 according to an embodiment of the present invention may be provided inside the barrel 101. The low temperature part 201-1 of the first Peltier element 104-1 is in contact with the grid seating part 102 inside the barrel 101, and the high temperature part 202-1 is in contact with the heat transfer rod 106 to be described later. do.

The heat transfer rod 106 is configured to transfer heat generated in the high temperature portion 202-1 of the first Peltier element 104-1 to the outside. The heat transfer rod 106 may transfer heat in a conductive manner. To this end, the heat transfer rod 106 may be made of a material with high thermal conductivity, and as a specific example, may be made of oxygen-free copper.

The heat transfer rod 106 may be provided in a form that penetrates the interior of the barrel 101 maintained in vacuum.

The high temperature portion 202-1 of the first Peltier element 104-1 is in contact with one end of the heat transfer rod 106. That is, when the low temperature part 201-1 of the first Peltier element 104-1 cools the grid seating part 102, the high temperature part 202-1 of the first Peltier element 104-1 cools the heat transfer rod ( 106) is heated.

Meanwhile, the interior of the TEM chamber 110 and the interior of the barrel 101 maintain a high vacuum state while observation is performed, as described above. Accordingly, the TEM chamber 110 and barrel 101 must have a significantly high blocking rate from the outside, and the walls of the TEM chamber 110 and the barrel 101 are generally designed to be thick and sturdy. .

Therefore, the second Peltier element 104-2 according to an embodiment of the present invention is a barrel 101 exposed to the outside of the TEM chamber 110 in order to effectively discharge heat from the inside of the TEM chamber 110 to the outside. ) is proposed to be provided at the other end of the.

The low temperature portion 201-2 of the second Peltier element 104-2 is in contact with the other end of the heat transfer rod 106 penetrating the barrel 101. Through this, the heat of the heat transfer rod 106 heated by the first Peltier element 104-1 may be cooled by the low temperature portion 201-2 of the second Peltier element 104-2.

The high temperature portion 202-2 of the second Peltier element 104-2 according to an embodiment of the present invention may be located outside the TEM chamber 110 and the barrel 101. That is, the outside of the TEM chamber 110 and the barrel 101 is exposed to the general atmospheric environment, and the high temperature part 202-2 of the second Peltier element 104-2 is exposed to the general atmospheric environment. Additionally, a heat sink 105 may be provided in the high temperature portion 202-2 of the second Peltier element 104-2 located externally.

The heat sink 105 is configured to effectively dissipate heat generated in the high temperature portion 202-2 of the second Peltier element 104-2 into the atmosphere. To this end, the heat sink 105 may be configured to include a plurality of heat dissipation wings to increase the contact area with air.

According to the configuration of the present invention described above, heat transferred by the heat transfer rod 106 (heat generated by the high temperature portion of the first Peltier element) is transmitted to the low temperature portion 201-2 of the second Peltier element 104-2. cooled by In addition, the heat of the heat transfer rod 106 is effectively discharged to the outside of the TEM chamber 110 and the barrel 101 by the high temperature portion 202-2 of the second Peltier element 104-2 exposed to the general atmospheric environment. It can be.

Meanwhile, since the first Peltier element 104-1 is located deep inside the TEM chamber 110, in order to supply power to the first Peltier element 104-1, it must be connected to the inside of the TEM chamber 110 with a wire. It has to be.

To this end, it is proposed that the wire of the first Peltier element 104-1 according to an embodiment of the present invention be provided in a form that penetrates the barrel 101. That is, the wire of the first Peltier element 104-1 located at one end of the barrel 101 may pass through the barrel 101 and then be drawn out through the other end of the barrel 101.

Meanwhile, even if the electric wire is pulled out to the other end of the barrel 101, there should be no effect on maintaining the vacuum within the barrel 101. Therefore, the sample holder 100 according to an embodiment of the present invention may further include a feedthrough 301 to enable wire extraction while maintaining a vacuum in the barrel 101.

In the case of the feed through 301, since it is designed to block air from the outside, it is generally large in volume. Therefore, it is difficult to simply arrange them side by side with the second Peltier element 104-2 or the heat sink 105 provided at the other end of the barrel 101.

In order to solve this problem, in one embodiment of the present invention, a hole is formed on the outer peripheral surface of the barrel 101, and the first Peltier element 104-1 is connected through a branch pipe 302 connected to the formed hole. It is proposed to pass the electric wire through. The branch pipe 302 may be formed at a right angle to the barrel 101 as shown in FIGS. 1 and 3, but the present invention is not necessarily limited to a right angle.

That is, one end of the branch pipe 302 may be coupled to the side hole of the barrel 101, and the other end of the branch pipe 302 may be connected to the feed through 301 described above.

The inside of the branch pipe 302 may also be maintained as a vacuum like the inside of the barrel 101. That is, the TEM chamber 110, barrel 101, and branch tube 302 may form a sealed space as a whole.

The path of the wire of the first Peltier element 104-1 passing through the branch pipe 302 connected to the side of the barrel 101 is shown as a dotted line 303 in FIG. 1.

In this way, when the wire of the first Peltier element 104-1 is connected through the branch pipe 302, the wire can be effectively connected deep into the TEM chamber 110, and the TEM can be connected through the feed-through 301 structure. The vacuum inside the chamber 110 and the barrel 101 can be efficiently maintained.

The sensing unit (not shown) is configured to sense the temperature of the sample, grid 103, or grid seating unit 102. Assuming that the user has set a predetermined temperature, it may be provided to detect whether the temperature exceeds the specified temperature. The sensed temperature may be transmitted to the control unit 501. The sensing unit (not shown) includes a first sensing unit and a heat transfer rod 106 for sensing the temperature of the sample, the grid 103 to the grid seating unit 102, and the second Peltier element 104-2 to the heat sink 105. ) may include a second sensing unit for sensing the temperature.

The control unit 501 generates control signals for controlling the first and second Peltier elements 104-1 and 104-2. Upon receiving the sensed temperature from the sensing unit (not shown), the control unit 501 controls the intensity of power provided to the first and second Peltier elements 104-1 and 104-2 based on the sensed temperature. , makes it possible to maintain a constant temperature for the sample.

Above, an embodiment of the sample holder for an electron microscope according to the present invention has been described, but this is explained as at least one embodiment, and the technical idea, structure, and operation of the present invention are not limited thereby, and the present invention The scope of the technical idea is not limited/restricted by the drawings or the description referring to the drawings. In addition, the concept and embodiments of the invention presented in the present invention can be used by those skilled in the art as a basis for modifying or designing other structures to achieve the same purpose of the present invention. , Equivalent structures modified or changed by those skilled in the art to which the present invention pertains are bound to the technical scope of the present invention described in the claims, and do not depart from the spirit or scope of the invention described in the claims. Various changes, substitutions, and changes are possible within limits.

Claims (7)

In the sample holder that holds the sample of the electron microscope in the vacuum chamber,
a barrel penetrating a side wall of the vacuum chamber;
A grid seating portion provided at one end of the barrel;
a first Peltier element coupled to the grid seating portion;
a second Peltier element provided at the other end of the barrel;
a heat transfer rod connecting the first and second Peltier elements to each other;
heat sink;
A wire for supplying power to the first Peltier element;
A branch pipe forming a hole on the outer peripheral surface of the barrel and connected to the formed hole; and
It includes a feed-through provided at one end of the branch pipe to allow extraction of the wire while maintaining the vacuum in the barrel,
The low temperature portion of the first Peltier element is fastened to the grid seating portion, and the high temperature portion of the first Peltier element is fastened to the heat transfer rod,
The low temperature part of the second Peltier element is fastened to the heat transfer rod, and the high temperature part of the second Peltier element is exposed to the outside of the vacuum chamber,
The high-temperature portion of the second Peltier element exposed to the outside is coupled with the heat sink to dissipate heat,
Electron microscope sample holder.
According to claim 1,
Characterized in that the material of the heat transfer rod is oxygen-free copper,
Electron microscope sample holder.
delete delete delete delete An electron microscope equipped with the electron microscope sample holder of claim 1 or 2.