Transmission electron microscope low-temperature sample rod using flexible structure for heat transfer

Abstract

The invention relates to a transmission electron microscope low-temperature sample rod using a flexible structure to transfer heat. The transmission electron microscope low-temperature sample rod comprises a liquid nitrogen Dewar tank; the sample rod comprises a sample rod body with a front-back through hollow cavity, a heat conduction rod and a flexible heat transfer rope, one end of the heat conduction rod extends into the liquid nitrogen Dewar tank, the other end of the heat conduction rod extends into the sample rod body, one end of the flexible heat transfer rope is wound and fixed on the heat conduction rod, and the other end of the flexible heat transfer rope is wound and fixed on the sample rod body. The other end of the sample rod extends to the outer end of the sample rod body; the sample rod head comprises a sample rod fixing outer frame and a sample rod temperature control part, the sample rod fixing outer frame is connected with the outer end of the sample rod body, the sample rod temperature control part is arranged on the sample rod fixing outer frame, the sample rod temperature control part is connected with the flexible heat transfer rope, and a heating element capable of heating a sample to be tested is further arranged on the sample rod temperature control part. Compared with the prior art, efficient heat conduction can be achieved, meanwhile, the thermal stress influence is reduced, and the temperature stability and the sample position stability are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of low-temperature in-situ testing equipment for transmission electron microscopes, and relates to a low-temperature sample rod for a transmission electron microscope using a flexible structure for heat transfer. Background Art

[0002] Transmission electron microscopy (TEM) is an essential analytical tool in fields such as materials science, biology, and nanotechnology. Its high-resolution capabilities reveal the microstructure and properties of samples. When studying superconductors, quantum materials, and temperature-sensitive samples, observation in cryogenic environments becomes particularly important, requiring high-performance cryogenic sample holder technology.

[0003] In high-resolution TEM imaging, sample position stability is crucial; even subnanometer-level drift can significantly impact image quality. Existing cryogenic sample holders often utilize direct liquid nitrogen or liquid helium cooling, which is not only complex to operate but also poses safety risks and high operating costs. Furthermore, maintaining a uniform and stable cryogenic environment during operation can be challenging, and sample position drift can easily occur, impacting image quality. Some improved cryogenic sample holders have introduced indirect cooling, but these approaches struggle to balance thermal and mechanical stability.

[0004] For example, CN201811649281.8 provides an in-situ cryogenic transmission electron microscope sample holder suitable for high-frequency signal transmission, comprising a dewar, a transition chamber, a sample holder, a sample holder head, and a coaxial cable. The coaxial cable utilizes four coaxial conductors, extending from the gap between the oxygen-free copper inner core and the outer rod, and then to the outside via a flange and a vacuum connector. Furthermore, a heating resistor is designed at the front end of the inner core, and a temperature sensor is designed near the fixed sample. However, this patent still frequently results in unpredictable sample drift during actual testing, making imaging quality difficult to guarantee. Summary of the Invention

[0005] The purpose of the present invention is to provide a transmission electron microscope low-temperature sample holder that uses a flexible structure to transfer heat. By adopting flexible elements, efficient heat conduction is achieved, while reducing the impact of thermal stress, improving temperature stability and sample position stability, etc.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] Through research, the present invention discovered that existing TEM cryogenic sample holders primarily utilize rigid heat-conducting structures. This structure, due to differential thermal expansion, is prone to generating thermal and mechanical stresses during the cooling process, leading to unpredictable sample drift. Therefore, the present invention develops a cryogenic sample holder structure that decouples the thermal conduction function from the mechanical support function. This structure utilizes flexible elements to achieve efficient heat conduction, while simultaneously reducing the impact of thermal stress and improving temperature stability and sample position stability. The present invention specifically comprises:

[0008] Liquid nitrogen dewar;

[0009] A sample holder, comprising a sample holder body having a hollow cavity extending from front to back, a heat conducting rod, and a flexible heat conducting rope. One end of the heat conducting rod extends into the interior of the liquid nitrogen dewar, and the other end extends into the interior of the sample holder body. The inner end of the sample holder body is sealed to the liquid nitrogen dewar. One end of the flexible heat conducting rope is wound around and fixed to the heat conducting rod, and the other end extends to the outer end of the sample holder body.

[0010] The sample rod head includes a sample rod fixing outer frame connected to the outer end of the sample rod body, and a sample rod temperature control portion arranged on the sample rod fixing outer frame. The sample rod temperature control portion can be used to place the sample to be tested. The sample rod temperature control portion is connected to the flexible heat transfer rope and is also provided with a heating element that can heat the sample to be tested.

[0011] Furthermore, the liquid nitrogen Dewar tank includes a Dewar inner tank and a Dewar outer tank, wherein the interior of the Dewar inner tank is used to store liquid nitrogen, the upper part of the Dewar inner tank is connected to the upper part of the Dewar outer tank through a bellows, and a closed cavity is formed between the Dewar inner tank and the Dewar outer tank.

[0012] Furthermore, the Dewar outer tank is further provided with a vacuum valve connected to the closed cavity;

[0013] A square boss for connecting with the sample shaft is provided on the outer side of the Dewar outer tank, and airtight connectors for connecting with the internal wires of the sample shaft are installed on both sides of the boss.

[0014] More preferably, a titanium alloy bushing is welded to the middle of the heat conducting rod, and the titanium alloy bushing is fixed in the boss through a pressure plate and a sealing ring, so that the two ends of the heat conducting rod extend into the Dewar inner tank and the sample rod body respectively;

[0015] The outer surface of the Dewar inner tank and the interior of the Dewar outer tank are both silver-plated.

[0016] Furthermore, the heat conducting rod is a copper rod.

[0017] Furthermore, the flexible heat transfer cord is braided from multiple strands of highly thermally conductive metal wire. More preferably, to ensure the flexible heat transfer cord remains flexible during operation rather than acting as a rigid rod, the present invention employs a pre-bent geometry and a controlled installation process: the flexible heat transfer cord is pre-bent within the sample rod in a wavy or spiral shape. Exemplarily, the wave amplitude is 2-5 mm and the wavelength is 10-20 mm.

[0018] In addition, preferably, the installation length of the flexible heat transfer rope is 5%-10% longer than the straight-line distance between the connection points at both ends, and the installation tension is controlled at 10%-20% of the yield strength of the metal wire. Through the dual mechanisms of geometric redundancy and prestress control, it is ensured that the heat transfer rope always remains in a non-stretched state throughout the entire process of thermal expansion and contraction, thereby effectively absorbing thermal deformation and attenuating the transmission of external mechanical vibrations.

[0019] Furthermore, an insulating wrapping layer is provided on the outside of the flexible heat transfer rope, and a plurality of integrally formed support members are provided on the insulating wrapping layer at intervals along the direction of the sample shaft, and the support members are in contact with and fixed to the inner wall of the sample shaft.

[0020] More preferably, the cross section of the support member is in the shape of a hexagonal star, and each corner has a circular hollow hole to provide a wire installation channel and a vacuum extraction channel.

[0021] Furthermore, the temperature control portion of the sample rod is provided with a through hole for connecting the flexible sensing rope.

[0022] Furthermore, the sample rod temperature control part and the sample rod fixing outer frame are connected by insulating screws.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] (1) Simplified the assembly and maintenance process, improving the installation efficiency and daily maintenance convenience of the equipment.

[0025] (2) Flexible connections can effectively absorb thermal deformation and reduce thermal drift during low-temperature in-situ testing.

[0026] (3) Attenuate external mechanical vibrations and improve imaging quality.

[0027] (4) The metal wire braided structure has lower processing costs than the heat-conducting metal thin rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A simplified diagram of the structure of a transmission electron microscope cryogenic sample holder for heat transfer to a flexible structure;

[0029] Figure 2 This is the overall cross-sectional view of the transmission electron microscope cryogenic sample holder;

[0030] Figure 3 This is a cross-sectional view of the heat transfer structure of the low-temperature sample holder of a transmission electron microscope;

[0031] Figure 4 This is a cross-sectional view of the support portion of the low-temperature sample holder for a transmission electron microscope;

[0032] Figure 5 This is a diagram showing the structure of the sample holder head for a transmission electron microscope cryogenic sample holder.

[0033] Figure 6 Schematic diagram of the structure of the heat transfer structure and the fixing method of the temperature control part of the low-temperature sample holder of the transmission electron microscope;

[0034] Description of the marks in the figure:

[0035] Liquid nitrogen Dewar tank 1, Dewar sealing cover 2, outer tank upper part 3, outer tank lower part 4, guide pin 5, vacuum valve 6, flange 7, inner tank upper part 8, inner tank middle part 9, inner tank lower part 10, boss 11, bellows 12, sample rod body 13, sealing ring 14, support 15, titanium alloy bushing 16, pressure plate 17, flexible heat transfer rope 18, copper rod 19, insulating wrapping layer 20, sample rod head 21, sample rod fixing outer frame 22, sample rod temperature control part 23, heating chip 24, Dewar outer tank 25, Dewar inner tank 26. DETAILED DESCRIPTION

[0036] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0037] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0039] In the following implementation manners or examples, unless otherwise specified, functional components or structures are conventional components or conventional structures used in the art to achieve corresponding functions.

[0040] In order to achieve efficient heat conduction while reducing the impact of thermal stress and improving temperature stability and sample position stability, the present invention provides a transmission electron microscope low-temperature sample holder using a flexible structure for heat transfer, see Figures 1 to 5 As shown, its specific structure includes:

[0041] Liquid nitrogen dewar tank 1;

[0042] The sample holder includes a sample shaft 13 having a hollow cavity extending from front to back, a heat conducting rod, and a flexible heat transfer rope 18. One end of the heat conducting rod extends into the interior of the liquid nitrogen dewar 1, and the other end extends into the interior of the sample shaft 13. The inner end of the sample shaft 13 is sealed with the liquid nitrogen dewar 1. One end of the flexible heat transfer rope 18 is wound and fixed on the heat conducting rod, and the other end extends to the outer end of the sample shaft 13.

[0043] The sample holder head 21 includes a sample holder fixing outer frame 22 connected to the outer end of the sample holder body 13, and a sample holder temperature control portion 23 disposed on the sample holder fixing outer frame 22. The sample holder temperature control portion 23 is used to place the sample to be tested. The sample holder temperature control portion 23 is connected to the flexible heat transfer cord 18 and is also provided with a heating element capable of heating the sample to be tested. It should be noted that the sample holder temperature control portion 23 is a fixed mounting structure and can be made of a heat-conducting material.

[0044] In some specific embodiments, please refer to Figure 2 As shown, the liquid nitrogen dewar tank 1 includes an inner dewar tank 26 and an outer dewar tank 25. The inner dewar tank 26 is used to store liquid nitrogen. The upper portion of the inner dewar tank 26 is connected to the upper portion of the outer dewar tank 25 via a bellows 12, forming a closed cavity between the inner dewar tank 26 and the outer dewar tank 25. The provision of the bellows 12 can provide the necessary deformation compensation capability while ensuring the vacuum sealing of the closed cavity, while also improving the thermal insulation performance.

[0045] In a more specific embodiment, the Dewar outer tank 25 is further provided with a vacuum valve 6 connected to the enclosed cavity. The vacuum valve 6 can be connected to an external vacuum device to evacuate the enclosed cavity and form a vacuum insulation interlayer. In addition, the outer side of the Dewar outer tank 25 is provided with a square boss 11 for connecting to the sample rod 13, and airtight connectors for connecting to the internal wires of the sample rod 13 are also installed on both sides of the boss 11. Here, the boss 11 and the airtight connector and other structures are conventional settings in the field and will not be repeated here. In addition, the boss 11 is also provided with a guide pin 5 for cooperating with external detection equipment.

[0046] In a more preferred embodiment, a titanium alloy bushing 16 is welded to the middle of the heat conducting rod. The titanium alloy bushing 16 is fixed to the boss 11 via a pressure plate 17 and a sealing ring, so that the ends of the heat conducting rod extend into the Dewar inner tank 26 and the sample rod 13, respectively. Preferably, the titanium alloy bushing 16 is designed as a tubular structure with an optimized aspect ratio. The titanium alloy has low thermal conductivity and matches the thermal expansion coefficient of the heat conducting copper rod, thereby providing insulation while avoiding thermal stress at low temperatures.

[0047] In addition, the outer surface of the Dewar inner tank 26 and the interior of the Dewar outer tank 25 are both silver-plated to further reduce heat loss.

[0048] In some specific embodiments, the heat conducting rod is a copper rod 19 .

[0049] In some specific embodiments, the flexible heat transfer rope 18 is woven from multiple strands of high thermal conductivity metal wires, and its effective cross-sectional area is 0.5 to 6.0 mm. 2 , preferably 1mm 2 In addition, the high thermal conductivity metal wire can be made of copper, silver, or aluminum. Here, the flexible heat transfer rope 18 can be connected to the heat conduction rod in a bundled and coated manner with metal braided wires. Specifically, the high thermal conductivity metal wire (for example, copper wire or other commonly used metal wire with a high thermal conductivity coefficient) constituting the flexible heat transfer rope 18 is divided into several strands, which are uniformly wrapped around the outer surface of the copper rod to form a multi-channel heat conduction interface. In addition, preferably, in order to ensure that the flexible heat transfer rope 18 always maintains a flexible feature rather than a rigid rod state during operation, the present invention adopts a pre-bent geometric design and a controlled installation process: the flexible heat transfer rope 18 is pre-bent in a wavy or spiral shape within the sample rod body 13. For example, the wave amplitude is 2-5 mm and the wavelength is 10-20 mm. At the same time, more preferably, the installation length of the flexible heat transfer rope 18 is 5%-10% longer than the straight-line distance between the connection points at both ends thereof, and the installation tension is controlled at 10%-20% of the yield strength of the metal wire. Through the dual mechanisms of geometric redundancy and prestress control, it is ensured that the heat transfer rope always remains in a non-stretched state during the entire process of thermal expansion and contraction, thereby effectively absorbing thermal deformation and attenuating the transmission of external mechanical vibration.

[0050] In some specific embodiments, please refer to Figure 4 As shown, the outside of the flexible heat transfer rope 18 is further provided with an insulating wrapping layer 20 , and a plurality of integrally formed support members 15 are provided on the insulating wrapping layer 20 at intervals along the direction of the sample rod 13 , and the support members 15 are in contact with and fixed to the inner wall of the sample rod 13 .

[0051] In a more preferred embodiment, the cross section of the support member 15 is in the shape of a hexagonal star, and each corner has a circular hollow hole to provide a wire installation channel and a vacuum extraction channel.

[0052] In some specific embodiments, the sample rod temperature control portion 23 is provided with a through hole for connecting the flexible sensing rope.

[0053] In some specific embodiments, the sample rod temperature control part 23 and the sample rod fixing outer frame 22 are connected by insulating screws. The insulating screws can avoid direct contact between the sample rod temperature control part 23 and the sample rod fixing outer frame 22, thereby reducing temperature interference on the sample rod temperature control part 23.

[0054] The above embodiments may be implemented individually or in any combination of two or more.

[0055] The above implementation is described in more detail below with reference to specific examples.

[0056] Example 1:

[0057] like Figure 1-Figure 2 As shown, the transmission electron microscope cryogenic sample holder of this embodiment mainly comprises four core components: a liquid nitrogen dewar 1, a sample holder body 13, a sample holder head 21, and a flexible heat transfer cord 18. The sample holder head 21 is used to support the sample and achieves stable temperature control in low-temperature environments through the flexible heat transfer structure.

[0058] The liquid nitrogen Dewar tank 1 adopts a double-layer vacuum insulation structure, including an inner Dewar tank 26 composed of an inner tank upper part 8, an inner tank middle part 9, and an inner tank lower part 10, and an outer Dewar tank 25 composed of an outer tank upper part 3 and an outer tank lower part 4. The inner Dewar tank 26 is used to store liquid nitrogen and conducts low temperature to the flexible heat transfer rope 18 through a copper rod 19, and finally to the sample rod head 21, achieving low-temperature control of the sample area (down to 100K). The inner tank upper part 8 and the outer tank upper part 3 are connected by a bellows 12, providing the necessary deformation compensation capability while ensuring vacuum sealing, while improving thermal insulation performance. To further reduce heat loss, the inner side of the outer Dewar tank 25 and the outer side of the inner Dewar tank 26 are both silver-plated.

[0059] One side of the Dewar outer tank 25 has a square boss 11 for fixedly connecting to the sample shaft 13. Flanges 7 are provided on both sides of the boss 11 for mounting an airtight connector connected to the wire inside the sample shaft 13.

[0060] The core heat transfer structure of the sample holder is as follows Figure 3As shown, one end of the copper rod 19 is inserted into the Dewar inner tank 26, and a titanium alloy bushing 16 is welded to the middle of the copper rod 19. The titanium alloy bushing 16 is fixed in the boss 11 of the upper part 3 of the outer tank through the pressure plate 17 and the sealing ring 14. A closed cavity is formed between the titanium alloy bushing 16, the Dewar sealing cover 2, the Dewar outer tank 25 and the Dewar inner tank 26, which is connected to the vacuum system through the vacuum valve 6 on the Dewar outer tank 26 to form a vacuum insulation interlayer. The flexible heat transfer rope 18 is woven from multiple strands of high thermal conductivity metal wire (such as copper, silver or aluminum), and its effective cross-sectional area is 1.0mm 2 One end is wrapped around the outer surface of the copper rod 19, and the other end extends to the sample rod head 21. Furthermore, the flexible heat transfer cord 18 is wavy within the sample rod 13, with a wave amplitude of approximately 3 mm and a wavelength of approximately 15 mm. Furthermore, the installation length of the flexible heat transfer cord 18 is preferably approximately 7% longer than the straight-line distance between its two connection points, and the installation tension is controlled at approximately 15% of the wire yield strength. Through the dual mechanisms of geometric redundancy and prestress control, the heat transfer cord is ensured to remain in a non-stretched state throughout the entire process of thermal expansion and contraction, thereby effectively absorbing thermal deformation and attenuating the transmission of external mechanical vibrations.

[0061] The insulating wrapping layer 20 outside the flexible heat transfer rope 18 and the support member 15 adopt an integrated structure and can be integrally formed by 3D printing technology. Figure 4 It adopts a hexagonal star-shaped cross-section, and each corner has a circular hollow, providing a vacuum extraction channel and a wire installation channel, while also reducing the heat conduction cross-sectional area and reducing heat loss.

[0062] like Figure 5 and Figure 6 As shown, the sample holder head 21 consists of a sample holder fixing frame 22 and a sample holder temperature control section 23, connected by four insulating screws. The low-temperature section 23 of the sample holder head has a through hole for securing the end of the flexible heat transfer cord 18, ensuring stable transfer of low temperatures to the sample area. The sample temperature is controlled using a heating chip 24. Its four electrodes measure the temperature in real time during heating, allowing the sample temperature to be precisely controlled to any temperature above the minimum low temperature limit.

[0063] The temperature control method of this embodiment is to first add liquid nitrogen to the dewar tank 26, wait for the sample holder temperature control section 23 to cool down, and then locally heat the sample head in the sample holder temperature control section 23 to reach the desired temperature. The heating method uses a heating resistor installed in the low-temperature portion of the sample holder head, or adopts an in-situ test chip with heating function.

[0064] It should be noted that the main innovation of the present invention lies in the use of flexible heat transfer ropes to replace the existing rigid heat conduction structure, decoupling the heat conduction function from the mechanical support function, thereby achieving efficient heat conduction, while reducing the impact of thermal stress and improving temperature stability and sample position stability. The remaining components or functional structures not involved or specifically described are all existing settings or conventional functional structures in low-temperature sample rods in this field and will not be repeated here.

[0065] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer, characterized in that: include: Liquid nitrogen dewar; A sample holder, comprising a sample holder body having a hollow cavity extending from front to back, a heat conducting rod, and a flexible heat conducting rope. One end of the heat conducting rod extends into the interior of the liquid nitrogen dewar, and the other end extends into the interior of the sample holder body. The inner end of the sample holder body is sealed to the liquid nitrogen dewar. One end of the flexible heat conducting rope is wound around and fixed to the heat conducting rod, and the other end extends to the outer end of the sample holder body. The sample rod head includes a sample rod fixing outer frame connected to the outer end of the sample rod body, and a sample rod temperature control portion arranged on the sample rod fixing outer frame and used to place the sample to be tested. The sample rod temperature control portion is connected to the flexible heat transfer rope and is also provided with a heating element for accurately controlling the temperature of the sample to be tested.

2. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 1, characterized in that: The liquid nitrogen dewar tank includes a dewar inner tank and a dewar outer tank, wherein the interior of the dewar inner tank is used to store liquid nitrogen, the upper part of the dewar inner tank is connected to the upper part of the dewar outer tank through a bellows, and a closed cavity is formed between the dewar inner tank and the dewar outer tank.

3. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 2, characterized in that: The Dewar outer tank is also provided with a vacuum valve connected to the closed cavity; A square boss for connecting with the sample shaft is provided on the outer side of the Dewar outer tank, and airtight connectors for connecting with the internal wires of the sample shaft are installed on both sides of the boss.

4. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 3, characterized in that: A titanium alloy bushing is welded to the middle of the heat conducting rod, and the titanium alloy bushing is fixed in the boss through a pressing plate and a sealing ring, so that the two ends of the heat conducting rod extend into the Dewar inner tank and the sample rod body respectively; The outer surface of the Dewar inner tank and the interior of the Dewar outer tank are both silver-plated.

5. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 1, characterized in that: The heat conducting rod is a copper rod.

6. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 1, characterized in that: The flexible heat transfer rope is woven from multiple strands of high thermal conductivity metal wires, and its effective cross-sectional area is 0.5 to 6.0 mm 2 .

7. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 6, characterized in that: The flexible heat transfer rope is pre-bent in a wave shape or a spiral shape in the sample shaft to ensure that it always remains in a non-stretched state during the thermal expansion and contraction process.

8. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 6, characterized in that: The installation length of the flexible heat transfer rope is 5-10% longer than the straight-line distance between the connection points at both ends, and the installation tension is controlled at 10-20% of the yield strength of the metal wire.

9. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 1, characterized in that: The flexible heat transfer rope is further provided with an insulating wrapping layer on the outside, and a plurality of integrally formed support members are provided on the insulating wrapping layer at intervals along the direction of the sample shaft, and the support members are in contact with and fixed to the inner wall of the sample shaft; The cross section of the support member is in the shape of a hexagonal star, and each corner has a circular hollow hole to provide a wire installation channel and a vacuum extraction channel.

10. The transmission electron microscope cryogenic sample holder using a flexible structure for heat transfer according to claim 1, characterized in that: The temperature control portion of the sample rod is provided with a through hole for connecting the flexible sensing rope; The sample rod temperature control part is connected to the sample rod fixing outer frame via insulating screws.

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