Multifunctional in-situ tem sample rod based on hermetic circular connectors

Abstract

The application discloses a multifunctional in-situ TEM sample rod based on an airtight circular connector and belongs to the technical field of in-situ experiment of a transmission electron microscope. The sample rod adopts a two-stage structure of'replaceable adapter front end + multi-path vacuum feedthrough integration', comprises a sample rod head, a front end thin rod, a replaceable adapter ring, an airtight circular connector, a rear end thick rod and a hand grip which are sequentially connected, and realizes compatibility adaptation of multiple platforms by docking the replaceable adapter ring with a transmission electron microscope lens barrel. The airtight circular connector integrates a multi-path feedthrough module and realizes multi-path signal crossing of a vacuum interface; a composite sealing structure area of the airtight circular connector comprises a metal lip seal, a labyrinth groove area and a polymer elastomer micro-capsule, forms adaptive two-stage dynamic sealing, and ensures ultra-high vacuum sealing performance and long plugging life. The application solves the problems of poor cross-platform compatibility, complex pipeline and insufficient sealing reliability of a traditional in-situ sample rod, and realizes the unity of high performance, high reliability and convenient operation.

Description

Technical Field

[0001] This invention relates to the field of transmission electron in-situ experimental technology, and in particular to a multifunctional in-situ TEM sample rod based on a hermetically sealed circular connector. Background Technology

[0002] Transmission electron microscopy (TEM) is an indispensable high-resolution analytical tool in materials science, nanotechnology, and life sciences. Its in-situ experimental techniques enable real-time, atomic-scale observation of dynamic processes in materials by applying external stimuli (such as electrical, optical, thermal, mechanical, liquid, or gaseous environments) to samples inside the microscope, greatly expanding the research boundaries of TEM. The core carrier for realizing these in-situ functions is a dedicated in-situ sample holder, which is responsible for accurately transmitting external signals and stimuli to a miniature sample chip located between the electron microscope's pole pieces.

[0003] However, current commercial in-situ TEM sample holder technology faces the following prominent bottlenecks, which severely restrict its widespread application and experimental efficiency: Poor platform compatibility and high customization costs: Currently, mainstream transmission electron microscope (TEM) manufacturers (such as FEI / ThermoFisher, JEOL, Hitachi, etc.) and different models of microscope tubes have varying standards for the vacuum interface at the sample rod insertion end. Traditional in-situ sample rods typically employ a "one-to-one" customized design, with the sealing and connection structure at the front end of the rod bound to a specific electron microscope interface. This means that users must completely re-customize the sample rod when changing electron microscope equipment or conducting similar experiments on different models of electron microscopes. This model not only incurs high purchase costs but also has a lengthy customization cycle, greatly limiting the versatility and efficiency of scientific research equipment, becoming a common pain point for users, especially those using multiple platforms. The contradiction between multifunctional integration and ultra-high vacuum reliability: To achieve in-situ studies involving multi-physics coupling, it is necessary to integrate and transmit electrical, optical signals, and various media such as gases and liquids within the sample rod. This requires the sample rod to be equipped with multiple feedthroughs to traverse the vacuum interface. However, the diameter of the TEM sample rod is strictly limited by the space of the pole shoe in the microscope tube. Under such extreme spatial constraints, it is extremely technically challenging to both integrate multiple independent channels with high density and ensure that the entire insertion and removal dynamic sealing interface can achieve and maintain the ultra-high vacuum required for transmission electron microscopy. Existing technical solutions often struggle to balance integration density and vacuum reliability: they either sacrifice some functions, employ complex multi-layer sealing structures resulting in a bulky rod with poor compatibility, or have limited sealing life, leading to increased leakage rates after frequent insertion and removal, affecting the electron microscope vacuum and posing operational risks.

[0004] In summary, developing a standardized, modular in-situ TEM sample holder that can simultaneously address issues such as cross-platform compatibility, high-density multifunctional integration and reliable vacuum sealing, as well as convenient and rapid operation, has become crucial for promoting the wider and more efficient application of in-situ electron microscopy. This invention aims to provide an innovative solution to address the aforementioned technical shortcomings. Summary of the Invention

[0005] In view of the deficiencies of the prior art described in the background section, the present invention aims to solve the following technical problems: Addressing the issues of poor cross-platform compatibility and high customization costs: How to design a universal interface that allows a single sample holder to be adapted to different brands and models of transmission electron microscopes without requiring overall customization, thereby reducing the cost and barriers for users to use multiple platforms.

[0006] To resolve the contradiction between multifunctional integration and reliable sealing in ultra-high vacuum under extreme space constraints: how to integrate efficient transmission channels for multiple signals such as electrical, optical, gas, and liquid signals within the limited diameter of the sample rod, and ensure that its dynamic sealing interface can meet the long-term stability requirements of the ultra-high vacuum environment of transmission electron microscopy.

[0007] To address the aforementioned technical problems, this invention provides a multifunctional in-situ TEM sample rod based on an airtight circular connector. Its core lies in employing a modular two-tier architecture that separates a "general-purpose functional core" from a "replaceable adapter front end." This in-situ TEM sample rod includes a sample rod head, a thin front end rod, various sizes of replaceable adapter rings, an airtight circular connector, a thicker rear end rod, and a handle, all connected sequentially. The front end of the sample rod head is equipped with a modular chip compartment for carrying the in-situ experimental chip. During use, the modular chip compartment is slid out from the front end of the sample rod head, and then the in-situ experimental chip containing the sample is inserted. The replaceable adapter ring is used to form a vacuum static seal with the vacuum flange of the transmission electron microscope tube. When it is necessary to change the electron microscope equipment, the replaceable adapter ring of different specifications can be replaced and matched with the vacuum flange of the transmission electron microscope tube to achieve compatibility adaptation of multiple specifications of transmission electron microscopes. The rear end of the replaceable adapter ring is detachably connected to the airtight circular connector through a locking structure. The front outer surface of the hermetic circular connector is provided with a composite sealing structure area, which cooperates with the rear end of the replaceable adapter ring to form a vacuum dynamic seal; the hermetic circular connector is encapsulated with a multi-way feedthrough module to enable electrical, optical, gas and liquid signals to pass through the vacuum seal boundary. The front thin rod, the rear thick rod, and the handle are all equipped with optical fibers, wires, gas microtubes, and liquid microtubes.

[0008] Preferably, the rear end face of the replaceable adapter ring is provided with a metal lip sealing conical surface and an adapter ring connection port; wherein, the metal lip sealing conical surface is a raised conical surface, used to mate with the composite sealing structure area of ​​the hermetically sealed circular connector; multiple adapter ring connection ports are provided along the circumference of the replaceable adapter ring, and the specifications of the adapter ring connection ports are selected according to different models of transmission electron microscopes, used to dock with the vacuum flange of different models of transmission electron microscope barrels; a sealing groove is opened at the adapter ring connection port, and an O-ring is embedded in the sealing groove, and the O-ring is statically sealed with the transmission electron microscope barrel.

[0009] Preferably, the composite sealing structure area includes a metal lip seal groove and a labyrinth groove area arranged radially from the inside to the outside. A metal sealing ring is placed in the metal lip seal groove. When the airtight circular connector is locked with the replaceable adapter ring, the metal lip seal groove and the metal lip seal mating cone surface of the replaceable adapter ring are tightly fitted to form a main seal. The labyrinth groove area is used to increase the leakage flow resistance at the main seal.

[0010] Preferably, the composite sealing structure area further includes a polymer elastomer microcavity disposed within the outer wall of the labyrinth groove area; the polymer elastomer microcavity is made of elastic material and pre-filled with low-pressure inert gas; when gas escapes from the main seal, the polymer elastomer microcavity adaptively deforms under the action of external pressure or temperature changes to compensate for the sealing gap, and together with the labyrinth groove area, constitutes an adaptive two-stage dynamic sealing system.

[0011] The present invention also provides a testing method based on the aforementioned in-situ TEM sample rod, comprising the following steps: S1. Before testing, select the corresponding replaceable adapter ring according to the model of the transmission electron microscope used. Align the metal lip seal of the rear end face of the replaceable adapter ring with the metal lip seal groove of the hermetically sealed circular connector, and lock the replaceable adapter ring and the hermetically sealed circular connector. The metal lip seal and the metal lip seal groove form the main seal. When gas escapes from the main seal and enters the labyrinth groove area, the polymer elastomer micro-cavities expand, thereby automatically compensating for the sealing gap. S2. Connect the replaceable adapter ring to the vacuum flange of the transmission electron microscope tube. At this time, the O-ring and the transmission electron microscope tube are statically sealed, realizing the compatibility adaptation between the in-situ TEM sample holder and the transmission electron microscope. S3. During testing, the in-situ experimental chip loaded with the sample is inserted into the modular chip compartment of the sample rod and locked. The optical window, electrodes and flow channels of the chip are automatically connected to the optical fiber, wires and gas and liquid microtubes inside the front thin rod through the sample rod. S4. Connect the external device to the rear end of the handle. Electrical, optical, gas, and liquid signals enter through the handle and are transmitted through the wires, optical fibers, gas microtubes, and liquid microtubes inside the thicker rod to the multi-path feedthrough module inside the hermetically sealed circular connector. The signals then pass through the sealed boundary via the multi-path feedthrough module and are transmitted through the wires, optical fibers, gas microtubes, and liquid microtubes inside the thinner rod to the sample tip. Finally, the signals act on the chip, turning on the transmission electron microscope. The transmitted electron beam passes through the chip, enabling multi-physics field coupling excitation and in-situ, real-time observation of the sample.

[0012] Compared with the prior art, the in-situ TEM sample holder provided by the present invention has at least the following beneficial effects: (1) Excellent cross-platform compatibility and economy: Through the innovative two-level architecture of "standardized airtight circular connector + replaceable adapter ring", the core functional modules are decoupled from the electron microscope interface. Users only need to replace the low-cost adapter ring to make the same high-performance sample rod compatible with multiple TEM models, which fundamentally solves the customization dilemma of "one rod per machine", significantly reduces equipment investment and usage threshold, and realizes "one design, multiple platforms universal".

[0013] (2) Breakthrough in the technical bottleneck of multi-functional and high-reliability integration in a small space: High-density multi-channel feedthrough modules (electric, optical, gas, and liquid) were successfully integrated in the airtight circular connector, and a composite sealing structure (labyrinth groove + metal lip seal + polymer elastomer micro-cavity) was adopted. Under the limitation of the diameter of the standard sample rod, independent transmission of multiple signals and excellent ultra-high vacuum dynamic sealing performance were realized at the same time, providing a reliable foundation for in-situ research on multi-physics coupling.

[0014] (3) Significantly improved experimental operation efficiency and overall system reliability: The modular chip compartment and quick-connect interface design enable chip replacement to be completed in a short time, and all interfaces are automatically aligned. The integrated built-in routing design replaces the easily damaged external piping, completely eliminating the risk of connection failure, leakage and signal interference caused by external vibration and pulling, thereby greatly improving the convenience of experimental operation, data repeatability and long-term stability of the system. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall in-situ sample holder for transmission electron microscopy provided in an embodiment of this application.

[0016] Figure 2 A detailed schematic diagram of the in-situ sample rod head for transmission electron microscopy provided in an embodiment of this application.

[0017] Figure 3 A schematic diagram of the thin rod structure at the front end of the in-situ sample rod for transmission electron microscopy provided in an embodiment of this application.

[0018] Figure 4 A schematic diagram of the in-situ sample rod adapter ring structure for transmission electron microscopy provided in this application embodiment.

[0019] Figure 5 A schematic diagram of a gas-tight circular connector for an in-situ transmission electron microscope sample rod provided in an embodiment of this application.

[0020] Figure 6 This is a schematic diagram of the rear thick rod and hand grip structure of the in-situ sample rod for transmission electron microscopy provided in the embodiments of this application.

[0021] In the picture: 1-Sample probe head, 11-Modular chip compartment, 12-Chip fixing slot, 13-Upper window, 14-Fiber optic alignment port, 15-Fiber optic cable inside the probe head, 16-Electrode contact slot, 17-Multifunctional integrated microfluidic substrate; 2-Front-end thin rod, 21-Fiber optic quick connector, 22-Gas microtube quick connector, 23-Liquid microtube quick connector, 24-Pad, 25-Flange connection, 26-Flange; 3- Replaceable adapter ring, 31 Metal lip seal with conical surface, 32- Adapter ring connector, 33- O-ring; 4-Airtight circular connector, 41-Multi-channel feedthrough module, 411-Fiber optic vacuum feedthrough, 412-Gas microtube vacuum feedthrough, 413-Liquid microtube vacuum feedthrough, 414-Spring pin vacuum feedthrough, 42-Insulating support, 43-Composite sealing structure area, 431-Metal lip seal groove, 432-Labyrinth groove area, 433-Polymer elastomer micro-cavity, 44-Metal shell, 441-Bayonet thread; 5-Rear thick rod, 51-Fiber optic interface, 52-Gas channel interface, 53-Liquid channel interface, 54-Circuit interface; 6-Hand grip, 61-Fiber optic port, 62-Gas port, 63-Liquid port, 64-Power interface, 65-Guide sheath. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings. These embodiments are used to explain the present invention, but are not intended to limit its scope. It should be noted that the accompanying drawings are used to assist in explaining the structure and working principle of the present invention; their scale and dimensions may not necessarily reflect the actual size of the components. Some structures may be simplified, enlarged, or partially sectional for clarity, and the positions of certain components may be appropriately adjusted without affecting the implementation of the technical solution.

[0023] The directional descriptions used in this document, such as "front end," "rear end," "inner side," "outer side," "above," and "below," all refer to the end closer to the sample in the normal installation state as "front end" and the end farther from the sample as "rear end," and should be understood with reference to the conventional perspective shown in the accompanying drawings. They should not be construed as limiting the scope of protection of this invention.

[0024] Furthermore, the ordinal numbers such as "first" and "second" appearing in the instruction manual are only used to distinguish different parts with the same or similar structure, and do not indicate any order, quantity or importance.

[0025] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. The following description is based on the preferred embodiment of the present invention, but the present invention is not limited to the described embodiment. Any modifications or equivalent substitutions made by those skilled in the art within the scope of the claims should be included within the protection scope of the present invention.

[0026] In this text, "front end" refers to the end closest to the transmission electron microscope sample chamber, and "rear end" refers to the end closest to the operator. The reference numerals in the accompanying drawings are consistent with those in the main text and figures of the instruction manual.

[0027] Figure 1 This is a schematic diagram of a multifunctional in-situ TEM sample rod based on a hermetically sealed circular connector, provided by an embodiment of the present invention. It is a slender rod-shaped structure, consisting of a sample rod head 1, a thin front rod 2, multiple replaceable adapter rings 3, a hermetically sealed circular connector 4, a thicker rear rod 5, and a handle 6 connected sequentially from front to back. The replaceable adapter ring 3 is used to connect the hermetically sealed circular connector 4 to the vacuum flange of the transmission electron microscope tube. The sample rod integrates multiple transmission channels for electricity, light, gas, and liquid. The external interfaces of these channels include an optical fiber port 61, a gas port 62, a liquid port 63, and a power interface 64. All external interfaces are concentrated within the handle 6.

[0028] The sample rod head 1 is mechanically fixed to the very front end of the thin rod 2 via its base, such as... Figure 2 Its core component is the modular chip compartment 11, which is designed with a standardized interface for quick insertion and removal of multifunctional in-situ experimental chips containing samples. The chip fixing slot 12 is located on the side wall or bottom of the modular chip compartment 11 and cooperates with the protrusions / grooves on the edge or bottom of the chip to achieve quick insertion, removal and locking of the chip. The chip compartment 11 has an upper window 13 and a corresponding lower window (not shown in the figure) at the top and bottom, respectively, for the transmission electron beam to pass through.

[0029] Between the sample tip 1 and the front thin rod 2, there is a multifunctional integrated microfluidic substrate 17. This multifunctional integrated microfluidic substrate 17 is made of high-strength ceramic material and has conductive lines, optical waveguide channels, and gas and liquid microfluidic channels arranged in parallel inside. At the connection between the chip compartment 11 and the multifunctional integrated microfluidic substrate 17, there is an optical fiber alignment port 14, a contact interface, and a flow channel opening. Among them, the optical waveguide channel is used to carry the optical fiber 15 inside the tip. One end of the optical fiber 15 inside the tip is connected to the optical fiber inside the front thin rod 2, and the other end is connected to the chip optical window through the optical fiber alignment port 14. Electrode contact slots 16 are installed on the conductive lines. The electrode contact slots 16 contain contacts for transmitting electrical signals. One end of the contact is connected to the wire inside the front thin rod 2, and the other end is in contact with the chip electrode through the contact interface. One end of the gas and liquid microfluidic channels is connected to the gas microtube and liquid microtube inside the front thin rod 2, respectively, and the other end is connected to the chip flow channel through the flow channel opening.

[0030] In this embodiment, the gas and liquid microchannel cross-section of the multifunctional integrated microchannel substrate 17 is rectangular or circular with a diameter of tens to hundreds of micrometers.

[0031] like Figure 3 The front-end thin rod 2 is a slender metal tube that integrates parallel optical fibers, wires, gas microtubes, and liquid microtubes. The rear end of the front-end thin rod 2 features an integrated quick-connect area, which includes: an optical fiber quick connector 21 for quickly connecting / disconnecting the optical fiber from the front-end thin rod 2 to the optical fiber vacuum feedthrough 411 from the hermetic circular connector 4; gas microtube quick connectors 22 and 23 for quickly connecting the microtubes from the front-end thin rod 2 to the gas microtube vacuum feedthrough 412 and liquid microtube vacuum feedthrough 413 from the hermetic circular connector 4, respectively; and a solder pad 24 for soldering or crimping the wires from the front-end thin rod 2 to the spring pin vacuum feedthrough 414 from the hermetic circular connector 4. The rear end of the front-end thin rod 2 has a flange connection port 25, which is fixed to a flange 26 by a set of screws. This flange 26 serves as a transition piece, rigidly connecting the front-end thin rod 2 to the front end face of the hermetic circular connector 4.

[0032] Figure 4This is a schematic diagram of the replaceable adapter ring 3. The replaceable adapter ring 3 is one of the core components for achieving cross-platform compatibility and has a ring-shaped structure. The rear end face of the replaceable adapter ring 3 has a precision-machined metal lip-sealing conical surface 31, which mates with the front end face of the hermetically sealed circular connector 4 to form a primary vacuum seal. Multiple adapter ring connection ports 32 are located on the outer side of the replaceable adapter ring 3. Their size, thread specifications, or flange standards can be customized according to different brands and models of transmission electron microscope (TEM) vacuum interfaces, thus forming multiple replaceable adapter rings 3 of different specifications. A sealing groove is formed at the adapter ring connection port 32, with an embedded O-ring 33, to form a reliable static seal when the replaceable adapter ring 3 is mated with the vacuum flange of the TEM tube. By replacing the replaceable adapter rings 3 with adapter ring connection ports 32 of different specifications, the same sample rod can be adapted to different TEM platforms.

[0033] Figure 5 This is a schematic diagram of the structure of the hermetic circular connector 4. The hermetic circular connector 4 is the core integrated module of this invention, undertaking the functions of vacuum isolation and multi-channel signal feedthrough. Its exterior is a metal shell 44, the front end of which is fixed to the front thin rod 2 via a flange 26. The outer surface of the front end of the metal shell 44 is machined with a bayonet thread 441, which is locked to the adapter ring 3 by screws.

[0034] An insulating support 42 is located inside the metal casing 44, and the multi-channel feedthrough module 41 is encapsulated within the insulating support 42. This module integrates at least the following four independent vacuum feedthroughs: fiber optic vacuum feedthrough 411, used to enable optical signals to pass through the vacuum interface; gas microtube vacuum feedthrough 412, used to enable gas media to pass through the vacuum interface; liquid microtube vacuum feedthrough 413, used to enable liquid media to pass through the vacuum interface; and spring pin vacuum feedthrough 414, used to enable electrical signals to pass through the vacuum interface.

[0035] In this embodiment, the insulating support 42 is made of high-alumina ceramic.

[0036] A composite sealing structure region 43 is machined around the outer surface of the front end of the metal housing 44. This region includes, radially from the inside out, a metal lip seal groove 431 for installing a metal sealing ring and a labyrinth groove region 432 for increasing leakage flow resistance. When the replaceable adapter ring 3 is locked with the hermetic circular connector 4, the metal lip seal mating cone surface 31 on the rear end face of the replaceable adapter ring 3 is pressed into this region of the metal lip seal groove 431, forming a dynamic seal that meets the requirements of ultra-high vacuum, serving as the main seal. An annular cavity is also machined within the outer wall of the labyrinth groove region 432, and a polymer elastomer microcapsule 433 is embedded inside the annular cavity. This polymer elastomer microcapsule 433 is made of a material with good vacuum compatibility and elasticity (such as perfluoroether rubber) and can be pre-filled with a small amount of low-pressure inert gas (such as helium). When the in-situ TEM sample rod undergoes long-term use, and nanoscale wear occurs on the main sealing surface, leading to an increased leakage rate, a small amount of gas escaping from the main sealing surface enters the labyrinth groove region 432. This generates micro-pressure on the polymer elastomer micro-cavities 433 behind them. Under this micro-pressure or their own elastic restoring force, the polymer elastomer micro-cavities 433 expand, applying an additional radial or axial compensating force to the main seal, thereby automatically "tightening" the sealing gap. Furthermore, the thermal expansion coefficient of the polymer elastomer micro-cavities 433 can be designed to compensate for dimensional mismatches caused by temperature changes. The polymer elastomer micro-cavities 433 and the labyrinth groove region 432 together constitute an adaptive two-stage dynamic sealing system. like Figure 6 The rear end of the airtight circular connector 4 is fixedly connected to the front end of the rear thick rod 5. The rear thick rod 5 has a larger diameter and integrates parallel optical fibers, wires, gas microtubes and liquid microtubes inside. The front end face of the rear thick rod 5 is provided with corresponding integrated interfaces, including an optical fiber interface 51, a gas channel interface 52, a liquid channel interface 53 and a circuit interface 54. These interfaces are respectively connected to the corresponding feedthrough input end at the rear end of the airtight circular connector 4.

[0037] The handle 6 is fixed to the rear end of the thicker rod 5 and serves as the handheld operating part. All external interfaces are centrally located at the rear end of the handle 6, including an optical fiber port 61, a gas port 62, a liquid port 63, and a power interface 64, which are connected to corresponding pipelines on the thicker rod 5 via internal routing. The front end of the handle 6 typically has a guide sheath 65 for engaging with the guide groove of the transmission electron microscope sample stage, ensuring smooth and precise insertion and removal. This invention also provides a testing method based on the aforementioned in-situ TEM sample rod, comprising the following steps: S1. Before testing, select the corresponding replaceable adapter ring 3 according to the model of the transmission electron microscope used, align the metal lip seal mating conical surface 31 of the replaceable adapter ring 3 with the metal lip seal groove 431 of the hermetic circular connector 4, and lock the replaceable adapter ring 3 and the hermetic circular connector 4. The metal lip seal mating conical surface 31 and the metal lip seal groove 431 form a dynamic main seal. When gas escapes from the main seal and enters the labyrinth groove area 432, the polymer elastomer micro-cavity 433 expands, thereby automatically compensating for the sealing gap. S2. Install the replaceable adapter ring 3 onto the transmission electron microscope tube interface and tighten it. At this time, the O-ring 33 and the transmission electron microscope tube are statically sealed, realizing the compatibility adaptation between the in-situ TEM sample rod and the transmission electron microscope. S3. During testing, the chip loaded with the sample is inserted into the modular chip compartment 11 of the sample rod head 1 and locked in place by the chip fixing slot 12. The electrodes, light windows and flow channels on the chip are automatically aligned with the contact interface, optical fiber alignment port 14 and flow channel in the sample rod head 1 and connected to the contact in the multifunctional integrated microfluidic substrate 17, the optical fiber 15 inside the rod head and the gas and liquid microfluidic channel respectively. S4. Connect external devices (laser, power supply, gas path, liquid path, etc.) to the various interfaces of the handle 6. Electrical, optical, gas, and liquid signals / mediums enter through the handle 6 and act precisely and in parallel on the chip of the sample rod head 1 through the various signal / medium paths, so as to realize multi-physics field coupling excitation and in-situ, real-time observation of the sample.

[0038] The four paths—optical, electrical, gaseous, and liquid—are as follows: Electrical path: The external electrical signal is connected through the power interface 64 of the handle 6, and transmitted through the wires inside the handle 6 and the rear thick rod 5 to the spring pin vacuum feed 414 in the hermetic circular connector 4. After crossing the vacuum boundary, it enters the internal wires through the solder pad 24 of the front thin rod 2 and is transmitted to the contact in the electrode contact slot 16 of the sample rod head 1. Finally, it contacts the chip electrode through the contact interface of the sample rod head 1.

[0039] Optical path: The external light signal is accessed through the fiber optic port 61 of the handle 6, and transmitted through the fiber optic cable inside the handle 6 and the thick rod 5 at the rear end to the fiber optic vacuum feedthrough 411 inside the airtight circular connector 4. After crossing the vacuum boundary, it enters the internal fiber optic cable through the fiber optic quick connector 21 of the thin rod at the front end and is transmitted to the fiber optic cable 15 inside the rod head of the sample rod head 1. Finally, it accurately illuminates the chip light window through the fiber optic alignment port 14.

[0040] Gas / liquid path: External gas or liquid enters through the gas port 62 or liquid port 63 of the handle 6, and is transmitted through the microtube inside the handle 6 and the rear thick rod 5 to the gas microtube vacuum feed 412 or liquid microtube vacuum feed 413 inside the airtight circular connector 4. After crossing the vacuum boundary, it enters the internal microtube through the gas microtube quick connector 22 or liquid microtube quick connector 23 of the front thin rod 2 and is delivered to the microchannel on the multifunctional integrated microchannel substrate 17, and finally enters the chip channel through the channel port.

[0041] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-functional in-situ TEM sample rod based on a hermetically sealed circular connector, characterized in that, The sample rod includes a sample head (1), a thin front rod (2), a variety of replaceable adapter rings (3), an airtight circular connector (4), a thick rear rod (5), and a handle (6) that are fixedly connected in sequence. The sample head (1) has a modular chip compartment (11) at the front end for carrying the in-situ experimental chip. When in use, the modular chip compartment (11) is slid out from the front end of the sample head (1), and then the in-situ experimental chip containing the sample is inserted. The replaceable adapter ring (3) is used to cooperate with the vacuum flange of the transmission electron microscope tube to form a vacuum static seal. When it is necessary to replace the electron microscope equipment, the replaceable adapter ring (3) of different specifications is replaced and cooperates with the vacuum flange of the transmission electron microscope tube to achieve compatibility adaptation of multiple specifications of transmission electron microscopes. The rear end of the replaceable adapter ring (3) is detachably connected to the airtight circular connector (4) through a locking structure. The airtight circular connector (4) has a composite sealing structure area (43) on the outer surface of its front end. The composite sealing structure area (43) cooperates with the rear end of the replaceable adapter ring (3) to form a vacuum dynamic seal. The airtight circular connector (4) is encapsulated with a multi-way feedthrough module (41) to enable electrical, optical, gas and liquid signals to pass through the vacuum seal boundary. The front thin rod (2), the rear thick rod (5), and the handle (6) are all equipped with optical fibers, wires, gas microtubes, and liquid microtubes.

2. The in-situ TEM sample holder according to claim 1, characterized in that, The sample rod head (1) has a chip fixing slot (12) on its side wall for quickly locking the in-situ experimental chip into the modular chip compartment (11). The rear section of the sample rod head (1) has a multifunctional integrated microfluidic substrate (17), which has parallel conductive lines, optical waveguide channels, and gas and liquid microfluidic channels. The conductive lines have electrode contact slots (16), which contain contact pieces. One end of the contact piece is connected to the wire in the front thin rod (2), and the other end is in contact with the chip electrode. The optical waveguide channel carries the optical fiber (15) inside the rod head. One end of the optical fiber (15) inside the rod head is connected to the optical fiber in the front thin rod (2), and the other end is connected to the chip optical window. One end of the gas and liquid microfluidic channel is connected to the gas microtube and liquid microtube in the front thin rod (2), and the other end is connected to the chip channel.

3. The in-situ TEM sample holder according to claim 2, characterized in that, The connection between the multifunctional integrated microfluidic substrate (17) and the modular chip compartment (11) is provided with an optical fiber alignment port (14), a contact interface and a flow channel opening. The optical fiber (15) inside the rod head is connected to the chip optical fiber through the optical fiber alignment port (14), the contact is in contact with the chip electrode through the contact interface, and the gas and liquid microfluidic channels are connected to the chip flow channel through the flow channel opening.

4. The in-situ TEM sample holder according to claim 1, characterized in that, The rear end face of the replaceable adapter ring (3) is provided with a metal lip sealing conical surface (31) and an adapter ring connection port (32); wherein, the metal lip sealing conical surface (31) is a raised conical surface, which is used to cooperate with the composite sealing structure area (43) of the hermetically sealed circular connector (4); multiple adapter ring connection ports (32) are provided along the circumference of the replaceable adapter ring (3), and the specifications of the adapter ring connection ports (32) are selected according to different models of transmission electron microscopes, which are used to dock with the vacuum flange of the tube of different models of transmission electron microscopes; a sealing groove is opened at the adapter ring connection port (32), and an O-ring (33) is embedded in the sealing groove, and the O-ring (33) is statically sealed with the tube of the transmission electron microscope.

5. The in-situ TEM sample holder according to claim 1, characterized in that, The airtight circular connector (4) also includes a metal shell (44), and the outer surface of the front end of the metal shell (44) is provided with a bayonet thread (441), which is used to connect the replaceable adapter ring (3); an insulating support (42) is provided inside the metal shell (44), and the multi-way feedthrough module (41) is encapsulated in the insulating support (42).

6. The in-situ TEM sample holder according to claim 1, characterized in that, The multi-channel feedthrough module (41) includes a spring needle vacuum feedthrough (414) for transmitting electrical signals, an optical fiber vacuum feedthrough (411) for transmitting optical signals, a gas microtube vacuum feedthrough (412) for transmitting gas, and a liquid microtube vacuum feedthrough (413) for transmitting liquid. The spring needle vacuum feedthrough (414) connects the wires in the front thin rod (2) and the rear thick rod (5), the optical fiber vacuum feedthrough (411) connects the optical fiber in the front thin rod (2) and the rear thick rod (5), the gas microtube vacuum feedthrough (412) connects the gas microtube in the front thin rod (2) and the rear thick rod (5), and the liquid microtube vacuum feedthrough (413) connects the liquid microtube in the front thin rod (2) and the rear thick rod (5).

7. The in-situ TEM sample holder according to claim 4, characterized in that, The composite sealing structure area (43) includes a metal lip sealing groove (431) and a labyrinth groove area (432) arranged radially from the inside to the outside. A metal sealing ring is placed in the metal lip sealing groove (431). When the airtight circular connector (4) is locked with the replaceable adapter ring (3), the metal lip sealing groove (431) and the metal lip sealing conical surface (31) of the replaceable adapter ring (3) fit tightly to form the main seal. The labyrinth groove area (432) is used to increase the leakage flow resistance at the main seal.

8. The in-situ TEM sample holder according to claim 7, characterized in that, The composite sealing structure area (43) also includes a polymer elastomer micro-cavity (433), which is disposed in the outer wall of the labyrinth groove area (432). The polymer elastomer micro-cavity (433) is made of elastic material and is pre-filled with low-pressure inert gas. When gas escapes from the main seal, the polymer elastomer micro-cavity (433) adapts to deformation under the action of external pressure or temperature changes, compensates for the sealing gap, and together with the labyrinth groove area (432), constitutes an adaptive two-stage dynamic sealing system.

9. The in-situ TEM sample holder according to claim 1, characterized in that, The handle (6) is equipped with a power interface (64), an optical fiber port (61), a gas port (62) and a liquid port (63), which are respectively connected to the wires, optical fibers, gas microtubes and liquid microtubes inside the rear thick rod (5) through the wires, optical fibers, gas microtubes and liquid microtubes inside the handle (6).

10. A testing method based on the in-situ TEM sample rod of claim 8, characterized in that, Includes the following steps: S1. Before testing, select the corresponding replaceable adapter ring (3) according to the model of the transmission electron microscope used. Align the metal lip seal mating cone surface (31) of the rear end face of the replaceable adapter ring (3) with the metal lip seal groove (431) of the airtight circular connector (4). Tighten the replaceable adapter ring (3) and the airtight circular connector (4). The metal lip seal mating cone surface (31) and the metal lip seal groove (431) form the main seal. When gas escapes from the main seal and enters the labyrinth groove area (432), the polymer elastomer micro cavities (433) expand, thereby automatically compensating for the sealing gap. S2. Connect the replaceable adapter ring (3) to the vacuum flange of the transmission electron microscope tube. At this time, the O-ring (33) and the transmission electron microscope tube are statically sealed, realizing the compatibility adaptation between the in-situ TEM sample rod and the transmission electron microscope. S3. During testing, the in-situ experimental chip loaded with the sample is inserted into the modular chip compartment (11) of the sample rod head (1) and locked. The optical window, electrodes and flow channels of the chip are automatically connected to the optical fiber, wires and gas and liquid microtubes inside the front thin rod (2) through the sample rod head (1). S4. Connect the external device to the rear end of the handle (6). The electrical, optical, gas and liquid signals enter through the handle (6) and are transmitted through the wires, optical fibers, gas microtubes and liquid microtubes inside the rear thick rod (5) to the multi-path feedthrough module (41) inside the airtight circular connector (4). The signals pass through the sealed boundary through the multi-path feedthrough module (41) and are then transmitted through the wires, optical fibers, gas microtubes and liquid microtubes inside the front thin rod (2) to the sample rod head (1). Finally, the signals act on the chip, turn on the transmission electron microscope, and the transmitted electron beam passes through the chip to realize the multi-physics field coupling excitation and in-situ, real-time observation of the sample.

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