Cold and hot dual-purpose transmission electron microscope in-situ sample rod

Abstract

The invention provides a cold and hot dual-purpose transmission electron microscope in-situ sample rod. The cold and hot dual-purpose transmission electron microscope in-situ sample rod comprises a handle, a rod body and a rod head, the handle part is provided with an external power supply interface and a cold source conduit interface, and can be externally connected with a heating power supply, a cold source and the like, so that current, a cooling medium and the like flow into the rod head part of the sample rod to realize a heating or refrigerating function. The rod head part is provided with an objective table, a cooling medium guide pipe, a sample loading device, a heat sensitive element and an electrode assembly. The sample fixing device is used for fixing a sample; the heat-sensitive chip is used for measuring the temperature of the sample area; the heating electrode part is used for heating the sample part after being connected with a power supply so as to realize transmission electron microscope observation of the sample in a high-temperature environment. By using the in-situ sample rod disclosed by the invention, direct heating and refrigeration can be realized to create high-temperature and low-temperature detection environments, and the experimental operation process of in-situ testing is simplified.

Description

Technical Field

[0001] The invention belongs to the field of transmission electron microscope accessories and nano material measurement, and belongs to the field of micro-nano material measurement research, and specifically provides a hot and cold dual-purpose in-situ sample rod. Background Art

[0002] Transmission electron microscopes can see submicroscopic or ultramicroscopic structures that cannot be seen clearly under optical microscopes, and are therefore often used in fields such as materials science and biology. The working principle of a transmission electron microscope is as follows: the electron beam emitted by the electron gun passes through the condenser lens along the optical axis of the microscope in a vacuum channel, and is focused by the condenser lens into a sharp, bright, and uniform light spot, which is then irradiated on the sample in the sample chamber; the electron beam after passing through the sample carries the structural information of the sample, with less electrons passing through dense areas and more electrons passing through sparse areas; after converging and focusing by the objective lens and primary magnification, the electron beam enters the lower intermediate lens and the first and second projection lenses for comprehensive magnification and imaging, and the magnified electron image is finally projected onto the fluorescent screen in the observation chamber; the fluorescent screen converts the electron image into a visible light image for the user to observe.

[0003] With the continuous development and innovation of transmission electron microscopy technology, researchers are no longer content with simply characterizing the structure and properties of micro- and nano-samples under simple experimental conditions. Instead, they pursue high-precision performance testing, linking the structural evolution of materials with their various properties. In situ techniques, which describe ongoing events or reactions in real time and on-site, rely on in-situ sample holders in transmission electron microscopy. With high spatial resolution at the atomic scale, in situ electron transmission microscopy allows for real-time dynamic observation of the entire reaction process, providing complete information on the morphology, structure, composition, and distribution of reactants and products.

[0004] Current in-situ TEM sample holders are complex, require high technical expertise, are expensive, and are difficult to procure. Currently, commercially available and independently developed temperature-controlled in-situ TEM sample holders are immature, suffering from limited functionality and uneven temperature control. To address these challenges, the present invention provides a dual-purpose, hot and cold TEM in-situ sample holder. Summary of the Invention

[0005] To achieve in-situ transmission electron microscopy observation at both high and low temperatures, the present invention addresses the shortcomings and problems of existing technologies and provides a dual-purpose hot and cold transmission electron microscopy in-situ sample holder. The technical solution of the present invention is as follows: The hot and cold dual-purpose transmission electron microscope in-situ sample holder comprises a sample holder handle, a first hollow rod, a second hollow rod, a sample holder head, a cooling medium delivery tube, a wire, a right-angle connecting tube, a retractable connecting tube, an electrode assembly, a stage, a thermal sensor, and a sample mount; The handle of the sample rod is located at the rear end of the sample rod, and has a cooling medium conveying pipe and a wire inside; the rear end of the handle has an external power supply interface and a cold source conveying interface, and the interfaces are connected with sealing rings to realize a vacuum environment inside the sample rod.

[0006] Further, the wire and the cooling medium conveying pipe pass through the rod body of the sample rod and reach the rod head part of the sample rod, and are symmetrically arranged; the wire is connected to the electrode assembly, and the cooling medium conveying pipe is communicated by a right-angle connecting pipe, so that the cooling medium enters the cooling medium conduit of the rod head of the sample rod; the interface connection parts are sealed to prevent the cooling medium from flowing out and affecting the experimental observation.

[0007] Further, the electrode assembly is fixed on the rod head of the sample rod by screws and can be detached, and a conductive probe is arranged at the front part of the electrode assembly to transmit current and fix the sample slice.

[0008] Further, the sample slice has a vacuum cavity inside and is divided into an observation area and a non-observation area; the observation area can directly realize electron transmission and has no influence on the observation result; the sample slice is integrated with an in-situ test chip, and a microcircuit is integrated in the non-observation area, which is used to supply power to the heating coil arranged around the observation area; when the coil is used, the cold source conveying is closed, and at this time, the sample rod is in a heating mode; protruding parts are symmetrically arranged on both sides of the sample slice to cooperate with the loading table.

[0009] Further, the loading table is installed on a rotating shaft which transversely penetrates the rod head of the sample rod and can rotate at a certain angle; meanwhile, a loading groove for loading the sample slice is provided, and rail grooves which cooperate with the protruding parts of the sample slice are arranged at both ends of the loading groove; meanwhile, observation holes corresponding to the observation area of the sample slice are provided on the surface of the loading groove.

[0010] Further, the loading table also has a pipeline for the flow of cooling medium, which is connected with the pipeline inside the rod head of the sample rod by an extensible connecting pipe, and the connecting parts are sealed; the cooling medium flows around the observation holes of the loading table to realize the circulation cooling of the sample observation area and further realize the observation of the low-temperature sample.

[0011] Further, a thermal sensor is arranged at the bottom of the loading groove of the loading table and close to the observation hole area, which is used to detect the temperature of the observation area and feed back the temperature data in real time to realize the real-time control and adjustment of the temperature and realize the in-situ observation of the sample.

[0012] Advantages and beneficial effects of the present application: The use of the dual-purpose sample rod allows in-situ observation of the sample in the transmission electron microscope, and real-time observation of the changes in the structure and properties of the sample during the process of heating or cooling the sample.

[0013] By heating or cooling the sample, the dynamic behavior of the material at different temperatures, such as phase transition, crystal growth, lattice distortion, etc. can be studied, which is of great significance to the study of the thermodynamic and kinetic properties of the material.

[0014] There are also certain benefits for the preparation of the sample. Some samples may undergo phase transition or instability at room temperature, or need to be treated at a specific temperature to exhibit the desired properties. The use of the dual-purpose sample rod can solve the preparation problems on these samples. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0016] Figure 1 The total assembly drawing of the dual-purpose in-situ sample rod for transmission electron microscope is shown, wherein 1 is the rod head of the sample rod, 2 is the first hollow rod, 3 is the second hollow rod, and 4 is the handle of the sample rod. Figure 2 The assembly drawing of the rod head of the sample rod is shown, wherein 5 is a right-angle connecting pipe, 6 is an electrode assembly, 7 is a telescopic connecting pipe, 8 is a sample mounting plate, 9 is a sample stage, and 10 is a wire. Figure 3 The interface sectional view of the second hollow rod is shown, wherein 11 is a cooling medium conveying pipe, and 12 is a wire channel. Figure 4 The schematic diagram of the sample mounting plate is shown, wherein 81 is an observation area, 82 is a microelectrode, and 83 is a heating coil. Figure 5 The schematic diagram of the sample stage is shown, wherein 91 is an observation hole, 92 is a thermosensitive sensor mounting groove, and 93 is a cooling medium flow pipe. Figure 6 The schematic diagram of the working condition of the dual-purpose in-situ sample rod for transmission electron microscope is shown. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0018] like Figures 1-5 FIG. 1 is a specific embodiment of the present invention. In this embodiment, a dual-purpose hot and cold transmission electron microscope in-situ sample holder includes a sample holder head 1, a first hollow rod 2, a second hollow rod 3, a sample holder handle 4, a right-angle connecting tube 5, an electrode assembly 6, a telescopic connecting tube 7, a sample slide 8, a stage 9, a wire 11, a cooling medium delivery tube 11 in the holder, a cooling source, and a power supply. The cooling source and the power supply are both externally connected to the outer end of the sample holder handle 4. The cooling medium is supplied by the cooling source through the cooling medium delivery tube 11 in the holder to the sample holder head 1, is connected to the delivery pipe inside the sample holder head 1 via the right-angle connecting tube 5, and is then connected to the cooling pipe inside the stage 9 via the telescopic connecting tube 7, thereby achieving annular cooling of the sample observation area, thereby enabling observation of sample changes at low temperatures. Furthermore, the pipeline interfaces such as the interface between the cooling source and the delivery pipeline at the rear end of the sample holder handle, the interface between the internal pipeline of the holder body and the right-angle connecting pipe, the interface between the right-angle connecting pipe and the internal pipeline of the sample holder head, the telescopic connecting pipe and the sample holder head, and the internal pipeline interface of the stage are all sealed to prevent leakage of the cooling medium and ensure a vacuum state inside the sample holder body.

[0019] The electrode assembly 6 is equipped with a conductive probe at its front end and a wire running through the interior of the rod at its rear end. These wires power the microcircuitry integrated into the sample holder 8. The electrode plate assembly 6 is secured to the head of the sample holder by screws. Once securely fastened, the conductive probe at its front end also provides some pressure on the sample holder.

[0020] The sample mount is integrated with a microcircuit and an in-situ test chip. The microcircuit is used to power the annular heating coil around the sample mount observation area, causing it to continuously generate heat, thereby increasing the temperature around the sample, and is used to observe changes in the sample at high temperatures.

[0021] The loading platform 9 has internal cooling medium channels that circulate the cooling medium, resulting in more uniform cooling, improved cooling effects, and faster cooling efficiency. A thermal sensor slot is located near the observation hole. For ease of installation, the slots are flanked by rails to secure the thermal sensor. The thermal surface sensor monitors the temperature of the observation area, providing feedback for more precise temperature control.

[0022] The working flow of using the device is as follows: preparing the sample of the material to be observed, and then encapsulating the sample into the sample holder after the sample is prepared to meet the observation conditions, which needs to ensure the vacuum environment of the cavity of the sample holder. The head part of the sample rod needs to be cleaned before loading to avoid affecting the observation results, and the cold source device also needs to be cleaned before use to avoid affecting the normal use due to icing phenomenon after the cooling medium flows. After the sample is loaded, the sample rod is inserted into the transmission electron microscope, and the temperature signal fed back by the thermal sensor is used to perform the heating or refrigeration operation.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A cold-thermal dual-purpose transmission electron microscope in-situ sample rod, characterized in that, The sample rod head (1), the first hollow rod (2), the second hollow rod (3), and the sample rod handle (4) are arranged at the front and rear ends of the sample rod respectively. The sample rod head is provided with a sample stage, an electrode assembly, a cooling medium conduit, and a heat-sensitive element. The rear end of the sample rod handle can be connected to a cooling source to cool the sample rod head. The first hollow rod and the second hollow rod are internally configured as a vacuum state, with a cooling source delivery pipe and a wire passing through. The electrode assembly receives power from the external handle power supply through the wire passing through the rod body.

2. The cold and hot dual-purpose transmission electron microscope in-situ sample rod according to claim 1, characterized in that: The cooling medium conduit has a right-angle connecting pipe and an extendable connecting pipe.

3. The cold and hot dual-purpose transmission electron microscope in-situ sample rod of claim 1, wherein: The right-angle connecting pipe is used to transfer the cooling medium from the rod body cooling source delivery pipe to the internal cooling medium pipeline of the sample rod head.

4. The cold and hot dual-purpose transmission electron microscope in-situ sample rod of claim 3, wherein: The sample stage part is provided with a clamping groove for loading sample components, which can cooperate with the sample mounting plate to realize the fixation and observation of the sample. The sample mounting plate has a sealed cavity, and the sample can be welded to the observation area of the sample mounting plate after FIB processing.

5. The cold and hot dual-purpose transmission electron microscope in-situ sample rod of claim 3, wherein: The sample mounting plate has a certain length of protruding part on both sides, which is used to realize the clamping cooperation with the sample stage clamping groove.

6. The hot and cold dual-purpose transmission electron microscope in-situ sample rod of claim 5, wherein: The upper layer of the sample mounting plate is paved with a microcircuit, which can accept the current transmission from the electrode assembly and supply power to the heating coil in the observation area to realize the heating function of the sample. The heating coil is located in the annular groove around the observation area of the upper plate of the sample mounting plate.

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